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Sample records for dengue japanese encephalitis

  1. MRI Findings In Dengue Encephalitis

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    Ashraf V.V

    2004-01-01

    Full Text Available Neurological manifestations are rare in dengue fever. Two cases with encephalopathy and systemic features of dengue fever with abnormal CSF and MR imaging are reported. Striking MRI finding was bilateral symmetrical thalamic lesions similar to those reported in Japanese encephalitis. This report highlights that MRI findings can be similar in dengue and Japanese encephalitis.

  2. Vectors expressing chimeric Japanese encephalitis dengue 2 viruses.

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    Wei, Y; Wang, S; Wang, X

    2014-01-01

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

  3. Dengue NS1 and prM antibodies increase the sensitivity of acute dengue diagnosis test and differentiate from Japanese encephalitis infection.

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    Gowri Sankar, S; Balaji, T; Venkatasubramani, K; Thenmozhi, V; Dhananjeyan, K J; Paramasivan, R; Tyagi, B K; John Vennison, S

    2014-05-01

    Accurate and early diagnosis of dengue infection is essential for dengue case management. In outbreak conditions, it is essential to include two different tests to diagnose dengue and the choice depends on the number of days after the onset of illness in which the sample is collected. During the laboratory diagnosis of dengue in late acute and convalescent phase by MAC-ELISA, it is necessary to rule out possible cross reactions of closely related flavivirus, such as Japanese encephalitis virus which is commonly co-circulating. In the present investigation, the usefulness of dengue virus NS1 and prM antibodies in diagnosing and differentiating dengue from Japanese encephalitis infection was assessed using samples collected during out-breaks. It was shown here that, detection of antibodies against dengue NS1 and prM proteins increases the sensitivity of dengue diagnosis until 15days. Moreover, detection of antibodies against both proteins was able to differentiate dengue from Japanese encephalitis infection.

  4. Change in Dengue and Japanese Encephalitis Seroprevalence Rates in Sri Lanka.

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    Chandima Jeewandara

    Full Text Available Sri Lanka has been affected by epidemics of dengue infections for many decades and the incidence and severity of dengue infections have been rising each year. Therefore, we investigated the age stratified seroprevalence of dengue infections in order to facilitate future dengue vaccine strategies. In addition, since the symptomatic dengue infections have increased during the past few decades, we also investigated the possible association with Japanese Encephalitis Virus (JEV antibody seropositivity with symptomatic dengue in a community cohort in Sri Lanka.1689 healthy individuals who were attending a primary health care facility were recruited. Dengue and JEV antibody status was determined in all individuals and JEV vaccination status was recorded.1152/1689 (68.2% individuals were seropositive for dengue and only 133/1152 (11.5% of them had been hospitalized to due to dengue. A significant and positive correlation was observed for dengue antibody seropositivity and age in children (Spearmans R = 0.84, p = 0.002 and in adults (Spearmans R = 0.96, p = 0.004. We observed a significant rise in the age stratified seroprevalence rates in children over a period of 12 years. For instance, in year 2003 the annual seroconversion rate was 1.5% per annum, which had risen to 3.79% per annum by 2014. We also found that both adults (p<0.001 and in children (p = 0.03 who were hospitalized due to dengue were more likely to be seropositive for JEV antibodies. However, 244 (91.4% of adults who were seropositive for JEV had not had the JEV vaccine.Dengue seroprevalence rates have risen significantly over the last 12 years in Sri Lanka, possibly due to increased transmission. As individuals who were hospitalized due to dengue were more likely to be seropositive for JEV, the possibility of cross-reactive assays and/or of JEV infection on immunity to the DENV and clinical disease severity should be further investigated.

  5. Change in Dengue and Japanese Encephalitis Seroprevalence Rates in Sri Lanka

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    Jeewandara, Chandima; Gomes, Laksiri; Paranavitane, S. A.; Tantirimudalige, Mihiri; Panapitiya, Sumedha Sandaruwan; Jayewardene, Amitha; Fernando, Samitha; Fernando, R. H.; Prathapan, Shamini

    2015-01-01

    Background Sri Lanka has been affected by epidemics of dengue infections for many decades and the incidence and severity of dengue infections have been rising each year. Therefore, we investigated the age stratified seroprevalence of dengue infections in order to facilitate future dengue vaccine strategies. In addition, since the symptomatic dengue infections have increased during the past few decades, we also investigated the possible association with Japanese Encephalitis Virus (JEV) antibody seropositivity with symptomatic dengue in a community cohort in Sri Lanka. Methods 1689 healthy individuals who were attending a primary health care facility were recruited. Dengue and JEV antibody status was determined in all individuals and JEV vaccination status was recorded. Results 1152/1689 (68.2%) individuals were seropositive for dengue and only 133/1152 (11.5%) of them had been hospitalized to due to dengue. A significant and positive correlation was observed for dengue antibody seropositivity and age in children (Spearmans R = 0.84, p = 0.002) and in adults (Spearmans R = 0.96, p = 0.004). We observed a significant rise in the age stratified seroprevalence rates in children over a period of 12 years. For instance, in year 2003 the annual seroconversion rate was 1.5% per annum, which had risen to 3.79% per annum by 2014. We also found that both adults (pdengue were more likely to be seropositive for JEV antibodies. However, 244 (91.4%) of adults who were seropositive for JEV had not had the JEV vaccine. Conclusions Dengue seroprevalence rates have risen significantly over the last 12 years in Sri Lanka, possibly due to increased transmission. As individuals who were hospitalized due to dengue were more likely to be seropositive for JEV, the possibility of cross-reactive assays and/or of JEV infection on immunity to the DENV and clinical disease severity should be further investigated. PMID:26696417

  6. The immunogenicity of tetravalent dengue DNA vaccine in mice pre-exposed to Japanese encephalitis or Dengue virus antigens.

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    Prompetchara, Eakachai; Ketloy, Chutitorn; Keelapang, Poonsook; Sittisombut, Nopporn; Ruxrungtham, Kiat

    2015-09-01

    Asian countries are an endemic area for both dengue (DENV) and Japanese encephalitis viruses (JEV). While JEV vaccines have been used extensively in this region, DENV vaccines remains under development. Whether preexisting naturally acquired or vaccination-induced immunity against JEV may affect the immune response to dengue vaccine candidate is unclear. In this study we used mice previously immunized with JEV vaccines to evaluate the impact on dengue-specific neutralizing antibody responses to a tetravalent dengue DNA vaccine candidate (TDNA). A tetravalent cocktail of plasmids encoding pre-membrane and envelope proteins from each dengue serotype was administered into mice which had been previously primed with inactivated or live-attenuated JEV vaccines, or dengue serotype2 virus (DENV-2). Neutralizing antibody response was measured employing a plaque reduction neutralization test at two weeks after the priming and at four weeks after the second dose of the dengue tetravalent plasmids. Inactivated or live-attenuated JEV vaccines, or DENV-2 induced low levels of neutralizing antibodies against the homologous viruses (JE and dengue virus, respectively). DENV-2 injection induced also low levels of cross-reactive antibodies against DENV-1, -3 and -4. JEV vaccines have no effect on the dengue-specific neutralizing antibody responses to the subsequent TDNA immunization. Pre-exposure to DENV-2 infection increased DENV-2 specific response neutralizing antibody to two doses of TDNA plasmids by six folds, but did not affect antibody response to other serotypes. Priming with JEV vaccines did not impact on dengue virus-specific neutralizing antibody response to a dengue TDNA vaccine candidate in mice.

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

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

    2014-05-23

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

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

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

    2014-12-01

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

  9. Protection against Japanese encephalitis by inactivated vaccines.

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    Hoke, C H; Nisalak, A; Sangawhipa, N; Jatanasen, S; Laorakapongse, T; Innis, B L; Kotchasenee, S; Gingrich, J B; Latendresse, J; Fukai, K

    1988-09-01

    Encephalitis caused by Japanese encephalitis virus occurs in annual epidemics throughout Asia, making it the principal cause of epidemic viral encephalitis in the world. No currently available vaccine has demonstrated efficacy in preventing this disease in a controlled trial. We performed a placebo-controlled, blinded, randomized trial in a northern Thai province, with two doses of monovalent (Nakayama strain) or bivalent (Nakayama plus Beijing strains) inactivated, purified Japanese encephalitis vaccine made from whole virus derived from mouse brain. We examined the effect of these vaccines on the incidence and severity of Japanese encephalitis and dengue hemorrhagic fever, a disease caused by a closely related flavivirus. Between November 1984 and March 1985, 65,224 children received two doses of monovalent Japanese encephalitis vaccine (n = 21,628), bivalent Japanese encephalitis vaccine (n = 22,080), or tetanus toxoid placebo (n = 21,516), with only minor side effects. The cumulative attack rate for encephalitis due to Japanese encephalitis virus was 51 per 100,000 in the placebo group and 5 per 100,000 in each vaccine group. The efficacy in both vaccine groups combined was 91 percent (95 percent confidence interval, 70 to 97 percent). Attack rates for dengue hemorrhagic fever declined, but not significantly. The severity of cases of dengue was also reduced. We conclude that two doses of inactivated Japanese encephalitis vaccine, either monovalent or bivalent, protect against encephalitis due to Japanese encephalitis virus and may have a limited beneficial effect on the severity of dengue hemorrhagic fever.

  10. Cross-protection induced by Japanese encephalitis vaccines against different genotypes of Dengue viruses in mice.

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    Li, Jieqiong; Gao, Na; Fan, Dongying; Chen, Hui; Sheng, Ziyang; Fu, Shihong; Liang, Guodong; An, Jing

    2016-01-28

    Dengue viruses (DENVs) and Japanese encephalitis virus (JEV) are closely related mosquito-borne flaviviruses that cause very high global disease burdens. Although cross-reactivity and cross-protection within flaviviruses have been demonstrated, the effect of JEV vaccination on susceptibility to DENV infection has not been well elucidated. In this study, we found that vaccination with the JEV inactivated vaccine (INV) and live attenuated vaccine (LAV) could induce cross-immune responses and cross-protection against DENV1-4 in mice. Despite the theoretical risk of immune enhancement, no increased mortality was observed in our mouse model. Additionally, low but consistently detectable cross-neutralizing antibodies against DENV2 and DENV3 were also observed in the sera of JEV vaccine-immunized human donors. The results suggested that both JEV-LAV and JEV-INV could elicit strong cross-immunity and protection against DENVs, indicating that inoculation with JEV vaccines may influence the distribution of DENVs in co-circulated areas and that the cross-protection induced by JEV vaccines against DENVs might provide important information in terms of DENV prevention.

  11. Japanese Encephalitis: Frequently Asked Questions

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    ... the vaccine, what should I do? What is Japanese encephalitis? Japanese encephalitis (JE) is a potentially severe disease. ... cause inflammation of the brain (encephalitis). Where does Japanese encephalitis occur? JE occurs in Asia and parts of ...

  12. Dengue encephalitis -a case report

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    P.C.Bhattacharyya; Jagdish Prasad Agarwal

    2009-01-01

    Encephalitis is an uncommon manifestation of dengue fever.Here we present a 4 years old female child from Northeast Region of India who suffered from dengue encephalitis.To our knowledge,this is probably the first diagnosed case of dengue fever from this region.

  13. Dengue encephalitis-A rare manifestation of dengue fever

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    Madi, Deepak; Achappa, Basavaprabhu; Ramapuram, John T; Chowta, Nityananda; Laxman, Mridula; Mahalingam, Soundarya

    2014-01-01

    The clinical spectrum of dengue fever ranges from asymptomatic infection to dengue shock syndrome. Dengue is classically considered a non-neurotropic virus. Neurological complications are not commonly seen in dengue. The neurological manifestations seen in dengue are encephalitis, meningitis, encephalopathy, stroke and Guillain-Barré syndrome. Dengue encephalitis is a rare disease. We report an interesting case of dengue encephalitis from Southern India. A 49-year-old gentleman presented with...

  14. Travelers' Health: Japanese Encephalitis

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    ... Awaiting FDA assessment Abbreviation: IM, intramuscular; FDA, US Food and Drug Administration 1 If potential for JE virus exposure continues. Table 3-07. Risk for Japanese encephalitis (JE), by country 1 COUNTRY AFFECTED AREAS ...

  15. Recognition of helper T cell epitopes in envelope (E) glycoprotein of Japanese encephalitis, west Nile and Dengue viruses.

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    Kutubuddin, M; Kolaskar, A S; Galande, S; Gore, M M; Ghosh, S N; Banerjee, K

    1991-01-01

    Helper T (Th) cell antigenic sites were predicted from the primary amino acid sequence (approximately 500 in length) of the envelope (E) glycoprotein (gp) of Japanese encephalitis (JE), West Nile (WN) and Dengue (DEN) I-IV flaviviruses. Prediction of Th epitopes was done by analyzing the occurrence of amphipathic segments, Rothbard-Taylor tetra/pentamer motifs and presence of alpha helix-preferring amino acids. The simultaneous occurrence of all these parameters in segments of E gp were used as criteria for prediction as Th epitopes. Only one cross reactive epitope was predicted in the C-terminal region of the E gp predicted segments of all flaviviruses analyzed. This region is one of the longest amphipathic stretch (approximately from 420 to 455) and also has a fairly large amphipathic score. Based on the predicted findings three selected peptides were synthesized and analyzed for their ability to induce in vitro T cell proliferative response in different inbred strains of mice (Balb/c, C57BL6, C3H/HeJ). Synthetic peptide I and II prepared from C-terminal region gave a cross reactive response to JE, WN and Den-II in Balb/c and C3H/HeJ mice. Synthetic peptide III prepared from N-terminal region gave a proliferative response to DEN-II in Balb/c strain only, indicating differential antigen presentation.

  16. Green synthesis and characterization of silver nanoparticles fabricated using Anisomeles indica: Mosquitocidal potential against malaria, dengue and Japanese encephalitis vectors.

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    Govindarajan, Marimuthu; Rajeswary, Mohan; Veerakumar, Kaliyan; Muthukumaran, Udaiyan; Hoti, S L; Benelli, Giovanni

    2016-02-01

    Mosquitoes (Diptera: Culicidae) represent a key threat for millions of people worldwide, since they act as vectors for devastating parasites and pathogens. In this scenario, eco-friendly control tools against mosquito vectors are a priority. Green synthesis of silver nanoparticles (AgNP) using a cheap, aqueous leaf extract of Anisomeles indica by reduction of Ag(+) ions from silver nitrate solution has been investigated. Bio-reduced AgNP were characterized by UV-visible spectrophotometry, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDX) and X-ray diffraction analysis (XRD). The acute toxicity of A. indica leaf extract and biosynthesized AgNP was evaluated against larvae of the malaria vector Anopheles subpictus, the dengue vector Aedes albopictus and the Japanese encephalitis vector Culex tritaeniorhynchus. Both the A. indica leaf extract and AgNP showed dose dependent larvicidal effect against all tested mosquito species. Compared to the leaf aqueous extract, biosynthesized AgNP showed higher toxicity against An. subpictus, Ae. albopictus, and Cx. tritaeniorhynchus with LC50 values of 31.56, 35.21 and 38.08 μg/mL, respectively. Overall, this study firstly shed light on the mosquitocidal potential of A. indica, a potential bioresource for rapid, cheap and effective AgNP synthesis.

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

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    Yunoki M

    2016-07-01

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

  18. Dengue encephalitis-A rare manifestation of dengue fever

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    Deepak Madi; Basavaprabhu Achappa; John T Ramapuram; Nityananda Chowta; Mridula Laxman; Soundarya Mahalingam

    2014-01-01

    The clinical spectrum of dengue fever ranges from asymptomatic infection to dengue shock syndrome. Dengue is classically considered a non-neurotropic virus. Neurological complications are not commonly seen in dengue. The neurological manifestations seen in dengue are encephalitis, meningitis, encephalopathy, stroke and Guillain-Barré syndrome. Dengue encephalitis is a rare disease. We report an interesting case of dengue encephalitis from Southern India. A 49-year-old gentleman presented with fever, altered sensorium and seizures. Dengue NS-1 antigen test was reactive. Dengue IgM was also positive. CSF PCR was negative for herpes simplex 1 & 2. Dengue encephalitis should be considered in the differential diagnosis of fever with altered sensorium, especially in countries like India where dengue is rampant.

  19. Cross-reactivity of human monoclonal antibodies generated with peripheral blood lymphocytes from dengue patients with Japanese encephalitis virus

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    Pipattanaboon C

    2013-08-01

    Full Text Available Chonlatip Pipattanaboon,1,3,8,* Tadahiro Sasaki,2,8,* Mitsuhiro Nishimura,2,8 Chayanee Setthapramote,1,8 Pannamthip Pitaksajjakul,1,4,8 Pornsawan Leaungwutiwong,1,3,8 Kriengsak Limkittikul,5,8 Orapim Puiprom,6 Mikiko Sasayama,6 Panjaporn Chaichana,6 Tamaki Okabayashi,6 Takeshi Kurosu,2,8 Ken-ichiro Ono,7,8 Pongrama Ramasoota,1,4,8 Kazuyoshi Ikuta2,8 1Center of Excellence for Antibody Research, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; 2Department of Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan; 3Department of Microbiology and Immunology, 4Department of Social and Environmental Medicine, 5Department of Tropical Pediatrics, Faculty of Tropical Medicine, Mahidol University, 6Mahidol-Osaka Center for Infectious Diseases, Bangkok, Thailand; 7Medical and Biological Laboratories Corporation Ltd, Nagano, Japan; 8JST/JICA, Science and Technology Research Partnership for Sustainable Development, Tokyo, Japan *These authors made an equal contribution to this study Background: Hybridomas that produce human monoclonal antibodies (HuMAbs against Dengue virus (DV had been prepared previously using peripheral blood lymphocytes from patients with DV during the acute and convalescent phases of a secondary infection. Anti-DV envelope glycoprotein (E 99 clones, anti-DV premembrane protein (prM 8 clones, and anti-DV nonstructural protein 1 (NS1 4 clones were derived from four acute-phase patients, and anti-DV E 2 clones, anti-DV prM 2 clones, and anti-DV NS1 8 clones were derived from five convalescent-phase patients. Methods and results: In the present study, we examined whether these clones cross-reacted with Japanese encephalitis virus (JEV, which belongs to the same virus family. Forty-six of the above-described 99 (46/99 anti-E, 0/8 anti-prM, and 2/4 anti-NS1 HuMAbs from acute-phase, and 0/2 anti-E, 0/2 anti-prM, and 5/8 anti-NS1 HuMAbs from convalescent-phase showed neutralizing activity against

  20. A novel dengue virus serotype 1 vaccine candidate based on Japanese encephalitis virus vaccine strain SA14-14-2 as the backbone.

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    Yang, Huiqiang; Li, Zhushi; Lin, Hua; Wang, Wei; Yang, Jian; Liu, Lina; Zeng, Xianwu; Wu, Yonglin; Yu, Yongxin; Li, Yuhua

    2016-06-01

    To develop a potential dengue vaccine candidate, a full-length cDNA clone of a novel chimeric virus was constructed using recombinant DNA technology, with Japanese encephalitis virus (JEV) vaccine strain SA14-14-2 as the backbone, with its premembrane (prM) and envelope (E) genes substituted by their counterparts from dengue virus type 1 (DENV1). The chimeric virus (JEV/DENV1) was successfully recovered from primary hamster kidney (PHK) cells by transfection with the in vitro transcription products of JEV/DENV1 cDNA and was identified by complete genome sequencing and immunofluorescent staining. No neuroinvasiveness of this chimeric virus was observed in mice inoculated by the subcutaneous route (s.c.) or by the intraperitoneal route (i.p.), while some neurovirulence was displayed in mice that were inoculated directly by the intracerebral route (i.c.). The chimeric virus was able to stimulate high-titer production of antibodies against DENV1 and provided protection against lethal challenge with neuroadapted dengue virus in mice. These results suggest that the chimeric virus is a promising dengue vaccine candidate.

  1. MRI in Japanese encephalitis

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    Kumar, S. [Sanjay Gandhi Post Graduate Inst. of Medical Sciences, Lucknow (India). Dept. of Radiology; Misra, U.K. [Sanjay Gandhi Post Graduate Inst. of Medical Sciences, Lucknow (India). Dept. of Neurology; Kalita, J. [Sanjay Gandhi Post Graduate Inst. of Medical Sciences, Lucknow (India). Dept. of Neurology; Salwani, V. [Sanjay Gandhi Post Graduate Inst. of Medical Sciences, Lucknow (India). Dept. of Radiology; Gupta, R.K. [Sanjay Gandhi Post Graduate Inst. of Medical Sciences, Lucknow (India). Dept. of Radiology; Gujral, R. [Sanjay Gandhi Post Graduate Inst. of Medical Sciences, Lucknow (India). Dept. of Radiology

    1997-03-01

    We document the MRI features in seven patients with Japanese encephalitis. MRI was carried out on a 1.5 T system within 10-60 days of onset. In all the patients MRI revealed bilateral thalamic lesions, haemorrhagic in five. Signal changes were present in the cerebrum in four patients, the midbrain and cerebellum in three each, the pons in two and the basal ganglia in one. The lesions were haemorrhagic in three of the four patients with lesions in the cortex, two of the three with lesions in the midbrain and cerebellum, but the pontine lesions were haemorrhagic in both patients. Spinal cord involvement was seen in one of the three patients who underwent MRI. In two patients MRI was repeated 3 years after the onset, showing marked reduction in abnormal signal; and all the lesions gave low signal on both T1- and T2-weighted images. Bilateral thalamic involvement, especially haemorrhagic, may be considered characteristic of Japanese encephalitis, especially in endemic areas. (orig.)

  2. Construction and preliminary investigation of a novel dengue serotype 4 chimeric virus using Japanese encephalitis vaccine strain SA14-14-2 as the backbone.

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    Li, Zhushi; Yang, Huiqiang; Yang, Jian; Lin, Hua; Wang, Wei; Liu, Lina; Zhao, Yu; Liu, Li; Zeng, Xianwu; Yu, Yongxin; Li, Yuhua

    2014-10-13

    For the purpose of developing a novel dengue vaccine candidate, recombinant plasmids were constructed which contained the full length cDNA clone of Japanese encephalitis (JE) vaccine strain SA14-14-2 with its premembrane (PreM) and envelope (E) genes replaced by the counterparts of dengue virus type 4 (DENV4). By transfecting the in vitro transcription products of the recombinant plasmids into BHK-21 cells, a chimeric virus JEV/DENV4 was successfully recovered. The chimeric virus was identified by complete genome sequencing, Western blot and immunofluorescent staining. Growth characteristics revealed it was well adapted to primary hamster kidney (PHK) cells. Its genetic stability was investigated and only one unintentional mutation in 5'-untranslated region (5'-UTR) was found after 20 passages in PHK cells. Neurotropism, neurovirulence and immunogenicity of the chimeric virus were tested in mice. Besides, the influence of JE vaccine pre-immunization on the neutralizing antibody level induced by the chimeric virus was illuminated. To our knowledge, this is the first chimeric virus incorporating the JE vaccine stain SA14-14-2 and DENV4. It is probably a potential candidate to compose a tetravalent dengue chimeric vaccine.

  3. Evaluation of chimeric DNA vaccines consisting of premembrane and envelope genes of Japanese encephalitis and dengue viruses as a strategy for reducing induction of dengue virus infection-enhancing antibody response.

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    Sjatha, Fithriyah; Kuwahara, Miwa; Sudiro, T Mirawati; Kameoka, Masanori; Konishi, Eiji

    2014-02-01

    Neutralizing antibodies induced by dengue virus (DENV) infection show viral infection-enhancing activities at sub-neutralizing doses. On the other hand, preimmunity against Japanese encephalitis virus (JEV), a congener of DENV, does not increase the severity of DENV infection. Several studies have demonstrated that neutralizing epitopes in the genus Flavivirus are mainly located in domain III (DIII) of the envelope (E) protein. In this study, chimeric premembrane and envelope (prM-E) gene-based expression plasmids of JEV and DENV1 with DIII substitution of each virus were constructed for use as DNA vaccines and their immunogenicity evaluated. Sera from C3H/He and ICR mice immunized with a chimeric gene containing DENV1 DIII on a JEV prM-E gene backbone showed high neutralizing antibody titers with less DENV infection-enhancing activity. Our results confirm the applicability of this approach as a new dengue vaccine development strategy.

  4. Eco-friendly larvicides from Indian plants: Effectiveness of lavandulyl acetate and bicyclogermacrene on malaria, dengue and Japanese encephalitis mosquito vectors.

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    Govindarajan, Marimuthu; Benelli, Giovanni

    2016-11-01

    Mosquitoes (Diptera: Culicidae) are a key threat for millions of people and animals worldwide, since they act as vectors for devastating pathogens and parasites, including malaria, dengue, Japanese encephalitis, filiariasis and Zika virus. Mosquito young instars are usually targeted using organophosphates, insect growth regulators and microbial agents. Indoor residual spraying and insecticide-treated bed nets are also employed. However, these chemicals have negative effects on human health and the environment and induce resistance in a number of vectors. In this scenario, newer and safer tools have been recently implemented to enhance mosquito control. The concrete potential of screening plant species as sources of metabolites for entomological and parasitological purposes is worthy of attention, as recently elucidated by the Y. Tu's example. Here we investigated the toxicity of Heracleum sprengelianum (Apiaceae) leaf essential oil and its major compounds toward third instar larvae of the malaria vector Anopheles subpictus, the arbovirus vector Aedes albopictus and the Japanese encephalitis vector Culex tritaeniorhynchus. GC-MS analysis showed that EO major components were lavandulyl acetate (17.8%) and bicyclogermacrene (12.9%). The EO was toxic to A. subpictus, A. albopictus, and C. tritaeniorhynchus, with LC50 of 33.4, 37.5 and 40.9µg/ml, respectively. Lavandulyl acetate was more toxic to mosquito larvae if compared to bicyclogermacrene. Their LC50 were 4.17 and 10.3µg/ml for A. subpictus, 4.60 and 11.1µg/ml for A. albopictus, 5.11 and 12.5µg/ml for C. tritaeniorhynchus. Notably, the EO and its major compounds were safer to three non-target mosquito predators, Anisops bouvieri, Diplonychus indicus and Gambusia affinis, with LC50 ranging from 206 to 4219µg/ml. Overall, this study highlights that H. sprengelianum EO is a promising source of eco-friendly larvicides against three important mosquito vectors with moderate toxicity against non-target aquatic

  5. [Japanese encephalitis in Southern Europe].

    Science.gov (United States)

    Cleton, Natalie; Koopmans, Marion; Braks, Marieta; Van Maanen, Kees; Reusken, Chantal

    2014-07-01

    In 2012, a fragment of the Japanese encephalitis virus (JEV) genome was isolated from a pool of Culex pipiens mosquitoes caught in 2010 and 2011 in Northern Italy. JEV has a broad geographical distribution in South and Southeast Asia and Oceania, and is the most important cause of viral encephalitis in Asia in humans and also causes encephalitis in horses and fertility problems in pigs. However, recently isolated JEV genome fragments in mosquitoes in Italy could be an indication of repeated introduction of JEV, enzootic circulation of JEV or a related virus in Southern Europe. Until more information is available, Japanese encephalitis remains a travel-related infectious disease for travellers to JEV endemic and epidemic areas outside of Europe.

  6. Vaccines for preventing Japanese encephalitis

    DEFF Research Database (Denmark)

    Schiøler, Karin Linda; Samuel, Miny; Wai, Kim Lay

    2007-01-01

    BACKGROUND: Vaccination is recognized as the only practical measure for preventing Japanese encephalitis. Production shortage, costs, and issues of licensure impair vaccination programmes in many affected countries. Concerns over vaccine effectiveness and safety also have a negative impact...... on acceptance and uptake. OBJECTIVES: To evaluate vaccines for preventing Japanese encephalitis in terms of effectiveness, adverse events, and immunogenicity. SEARCH STRATEGY: In March 2007, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library 2007, Issue 1......), MEDLINE, EMBASE, LILACS, BIOSIS, and reference lists. We also attempted to contact corresponding authors and vaccine companies. SELECTION CRITERIA: Randomized controlled trials (RCTs), including cluster-RCTs, comparing Japanese encephalitis vaccines with placebo (inert agent or unrelated vaccine...

  7. Co-positivity of anti-dengue virus and anti-Japanese encephalitis virus IgM in endemic area:co-infection or cross reactivity?

    Institute of Scientific and Technical Information of China (English)

    Kaleshwar Prasad Singh; Sakshi Shrivastav; Desh Deepak Singh; Amita Jain; Gitika Mishra; Parul Jain; Nidhi Pandey; Rachna Nagar; Shikha Gupta; Shantanu Prakash; Om Prakash; Danish Nasar Khan

    2014-01-01

    Objective:To report high co-positivity of anti-dengue virus(DV) and anti-Japanese encephalitis virus(JEV)IgM in an area endemic for both the viruses and to discuss the possibilities of co-infection.Methods:Serum samples from the patients who presented with fever, suspected central nervous system infection and thrombocytopenia, were tested for anti-DVIgM and anti-JEVIgM antibodies.Conventional reverse transcriptase polymerase chain reaction was done for detection ofDVRNA andJEVRNA.Results:Of1410 patient sera tested for anti-DV and anti-JEV antibodies,129(9.14%) were co-positive for both.This co-positivity was observed only in those months when anti-JEVIgM positivity was high.Titers of both anti-DVIgM and anti-JEV IgM were high in most of the co-positive cases.Among these129 co-positive cases,76 were tested by conventional reverse transcriptase polymerase chain reaction for both flaviviruses, of which eight cases were co-positive forDV andJEV.Conclusions:Co-infection with more than one flavivirus species can occur in hyperendemic areas.

  8. Cellular Immune Responses to Live Attenuated Japanese Encephalitis (JE Vaccine SA14-14-2 in Adults in a JE/Dengue Co-Endemic Area.

    Directory of Open Access Journals (Sweden)

    Lance Turtle

    2017-01-01

    Full Text Available Japanese encephalitis (JE virus (JEV causes severe epidemic encephalitis across Asia, for which the live attenuated vaccine SA14-14-2 is being used increasingly. JEV is a flavivirus, and is closely related to dengue virus (DENV, which is co-endemic in many parts of Asia, with clinically relevant interactions. There is no information on the human T cell response to SA14-14-2, or whether responses to SA14-14-2 cross-react with DENV. We used live attenuated JE vaccine SA14-14-2 as a model for studying T cell responses to JEV infection in adults, and to determine whether these T cell responses are cross-reactive with DENV, and other flaviviruses.We conducted a single arm, open label clinical trial (registration: clinicaltrials.gov NCT01656200 to study T cell responses to SA14-14-2 in adults in South India, an area endemic for JE and dengue.Ten out of 16 (62.5% participants seroconverted to JEV SA14-14-2, and geometric mean neutralising antibody (NAb titre was 18.5. Proliferation responses were commonly present before vaccination in the absence of NAb, indicating a likely high degree of previous flavivirus exposure. Thirteen of 15 (87% participants made T cell interferon-gamma (IFNγ responses against JEV proteins. In four subjects tested, at least some T cell epitopes mapped cross-reacted with DENV and other flaviviruses.JEV SA14-14-2 was more immunogenic for T cell IFNγ than for NAb in adults in this JE/DENV co-endemic area. The proliferation positive, NAb negative combination may represent a new marker of long term immunity/exposure to JE. T cell responses can cross-react between JE vaccine and DENV in a co-endemic area, illustrating a need for greater knowledge on such responses to inform the development of next-generation vaccines effective against both diseases.clinicaltrials.gov (NCT01656200.

  9. Cellular Immune Responses to Live Attenuated Japanese Encephalitis (JE) Vaccine SA14-14-2 in Adults in a JE/Dengue Co-Endemic Area.

    Science.gov (United States)

    Turtle, Lance; Tatullo, Filippo; Bali, Tanushka; Ravi, Vasanthapuram; Soni, Mohammed; Chan, Sajesh; Chib, Savita; Venkataswamy, Manjunatha M; Fadnis, Prachi; Yaïch, Mansour; Fernandez, Stefan; Klenerman, Paul; Satchidanandam, Vijaya; Solomon, Tom

    2017-01-01

    Japanese encephalitis (JE) virus (JEV) causes severe epidemic encephalitis across Asia, for which the live attenuated vaccine SA14-14-2 is being used increasingly. JEV is a flavivirus, and is closely related to dengue virus (DENV), which is co-endemic in many parts of Asia, with clinically relevant interactions. There is no information on the human T cell response to SA14-14-2, or whether responses to SA14-14-2 cross-react with DENV. We used live attenuated JE vaccine SA14-14-2 as a model for studying T cell responses to JEV infection in adults, and to determine whether these T cell responses are cross-reactive with DENV, and other flaviviruses. We conducted a single arm, open label clinical trial (registration: clinicaltrials.gov NCT01656200) to study T cell responses to SA14-14-2 in adults in South India, an area endemic for JE and dengue. Ten out of 16 (62.5%) participants seroconverted to JEV SA14-14-2, and geometric mean neutralising antibody (NAb) titre was 18.5. Proliferation responses were commonly present before vaccination in the absence of NAb, indicating a likely high degree of previous flavivirus exposure. Thirteen of 15 (87%) participants made T cell interferon-gamma (IFNγ) responses against JEV proteins. In four subjects tested, at least some T cell epitopes mapped cross-reacted with DENV and other flaviviruses. JEV SA14-14-2 was more immunogenic for T cell IFNγ than for NAb in adults in this JE/DENV co-endemic area. The proliferation positive, NAb negative combination may represent a new marker of long term immunity/exposure to JE. T cell responses can cross-react between JE vaccine and DENV in a co-endemic area, illustrating a need for greater knowledge on such responses to inform the development of next-generation vaccines effective against both diseases. clinicaltrials.gov (NCT01656200).

  10. Cellular Immune Responses to Live Attenuated Japanese Encephalitis (JE) Vaccine SA14-14-2 in Adults in a JE/Dengue Co-Endemic Area

    Science.gov (United States)

    Tatullo, Filippo; Bali, Tanushka; Ravi, Vasanthapuram; Soni, Mohammed; Chan, Sajesh; Chib, Savita; Venkataswamy, Manjunatha M.; Fadnis, Prachi; Yaïch, Mansour; Fernandez, Stefan; Klenerman, Paul; Satchidanandam, Vijaya; Solomon, Tom

    2017-01-01

    Background Japanese encephalitis (JE) virus (JEV) causes severe epidemic encephalitis across Asia, for which the live attenuated vaccine SA14-14-2 is being used increasingly. JEV is a flavivirus, and is closely related to dengue virus (DENV), which is co-endemic in many parts of Asia, with clinically relevant interactions. There is no information on the human T cell response to SA14-14-2, or whether responses to SA14-14-2 cross-react with DENV. We used live attenuated JE vaccine SA14-14-2 as a model for studying T cell responses to JEV infection in adults, and to determine whether these T cell responses are cross-reactive with DENV, and other flaviviruses. Methods We conducted a single arm, open label clinical trial (registration: clinicaltrials.gov NCT01656200) to study T cell responses to SA14-14-2 in adults in South India, an area endemic for JE and dengue. Results Ten out of 16 (62.5%) participants seroconverted to JEV SA14-14-2, and geometric mean neutralising antibody (NAb) titre was 18.5. Proliferation responses were commonly present before vaccination in the absence of NAb, indicating a likely high degree of previous flavivirus exposure. Thirteen of 15 (87%) participants made T cell interferon-gamma (IFNγ) responses against JEV proteins. In four subjects tested, at least some T cell epitopes mapped cross-reacted with DENV and other flaviviruses. Conclusions JEV SA14-14-2 was more immunogenic for T cell IFNγ than for NAb in adults in this JE/DENV co-endemic area. The proliferation positive, NAb negative combination may represent a new marker of long term immunity/exposure to JE. T cell responses can cross-react between JE vaccine and DENV in a co-endemic area, illustrating a need for greater knowledge on such responses to inform the development of next-generation vaccines effective against both diseases. Trial Registration clinicaltrials.gov (NCT01656200) PMID:28135273

  11. CT findings of Japanese encephalitis

    Energy Technology Data Exchange (ETDEWEB)

    Shoji, Hiroshi; Toyomasu, Teruo; Fukada, Makiko; Nakashima, Kenichi; Kaji, Masaro; Kobayashi, Kenji

    1984-04-01

    In this study, CT findings of eight patients with Japanese encephalitis were analyzed. In principle, CT scans were done at the acute stage, within 3 weeks of the onset, and at the convalescent stage, after from 1 month to 1 year. The results may be divided into three groups: normal scans, low-density lesions, and ventricular abnormalities. 1) Normal scans: CT findings in Cases 1 and 5, showed no abnormalities, although patient 5 had clinically severe encephalitis. 2) Low-density lesions: In Case 3, a slight low-density area was observed in the bilateral thalami only at the acute stage. CT scans in Case 4, obtained 2 and 4 months after the onset, exhibited low-density areas in the bilateral thalami, the left basal ganglia, and the left substantia nigra. In Case 7, diffuse low-density areas in the white matter were found 3 months after the onset. 3) Ventricular abnormalities: CT in Case 2 revealed a moderate dilatation of the ventricular system, which probably suggests normal-pressure hydrocephalus. In 2 other cases, a narrowing or dilatation of the lateral ventricle was observed. The CT findings regarding Japanese encephalitis were discussed in comparison with those of other viral encephalitides, particularly herpes simplex encephalitis.

  12. Recent advances in Japanese encephalitis

    Science.gov (United States)

    Basu, Anirban; Dutta, Kallol

    2017-01-01

    Japanese encephalitis is a flaviviral disease that is endemic to the South, Southeast Asia, and Asia Oceania regions. Given that about 60% of the world’s population (about 7.4 billion) resides in this region (about 4.4 billion), this disease poses a significant threat to global health. Active vaccination campaigns conducted in endemic countries have led to a decrease in the number of reported cases over the years. In this article, we strive to briefly highlight recent advances in understanding the role of microRNAs in disease pathology, focus on providing brief summaries of recent clinical trials in the field of Japanese encephalitis therapeutics, and review the current prophylactic strategies. PMID:28357054

  13. Eugenol, α-pinene and β-caryophyllene from Plectranthus barbatus essential oil as eco-friendly larvicides against malaria, dengue and Japanese encephalitis mosquito vectors.

    Science.gov (United States)

    Govindarajan, Marimuthu; Rajeswary, Mohan; Hoti, S L; Bhattacharyya, Atanu; Benelli, Giovanni

    2016-02-01

    Mosquito-borne diseases represent a deadly threat for millions of people worldwide. Eco-friendly mosquitocides are a priority. In Ayurvedic medicine, Plectranthus species have been used to treat heart disease, convulsions, spasmodic pain and painful urination. In this research, we evaluated the acute toxicity of essential oil from Plectranthus barbatus and its major constituents, against larvae of the malaria vector Anopheles subpictus, the dengue vector Aedes albopictus and the Japanese encephalitis vector Culex tritaeniorhynchus. The chemical composition of P. barbatus essential oil was analyzed by gas chromatography-mass spectroscopy. Nineteen components were identified. Major constituents were eugenol (31.12%), α-pinene (19.38%) and β-caryophyllene (18.42%). Acute toxicity against early third-instar larvae of An. subpictus, Ae. albopictus and Cx. tritaeniorhynchus was investigated. The essential oil had a significant toxic effect against larvae of An. subpictus, Ae. albopictus and Cx. tritaeniorhynchus, with 50% lethal concentration (LC50) values of 84.20, 87.25 and 94.34 μg/ml and 90% lethal concentration (LC90) values of 165.25, 170.56 and 179.58 μg/ml, respectively. Concerning major constituents, eugenol, α-pinene and β-caryophyllene appeared to be most effective against An. subpictus (LC50 = 25.45, 32.09 and 41.66 μg/ml, respectively), followed by Ae. albopictus (LC50 = 28.14, 34.09 and 44.77 μg/ml, respectively) and Cx. tritaeniorhynchus (LC50 = 30.80, 36.75 and 48.17 μg/ml, respectively). Overall, the chance to use metabolites from P. barbatus essential oil against mosquito vectors seems promising, since they are effective at low doses and could be an advantageous alternative to build newer and safer mosquito control tools.

  14. Genotype v Japanese encephalitis virus is emerging

    National Research Council Canada - National Science Library

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

    2011-01-01

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

  15. Human T cell responses to Japanese encephalitis virus in health and disease

    OpenAIRE

    Turtle, L.; Bali, T; Buxton, G; Chib, S.; Chan, S; Soni, M.; Hussain, M; H. Isenman; Fadnis, P; Venkataswamy, MM; Satishkumar, V; Lewthwaite, P; Kurioka, A; Krishna, S.; Shankar, MV

    2016-01-01

    Japanese encephalitis (JE) virus (JEV) is an important cause of encephalitis in children of South and Southeast Asia. However, the majority of individuals exposed to JEV only develop mild symptoms associated with long-lasting adaptive immunity. The related flavivirus dengue virus (DENV) cocirculates in many JEV-endemic areas, and clinical data suggest cross-protection between DENV and JEV. To address the role of T cell responses in protection against JEV, we conducted the first full-breadth a...

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

    Directory of Open Access Journals (Sweden)

    Liu Wen-Xin

    2010-09-01

    Full Text Available Abstract Background Differential diagnose of Japanese encephalitis virus (JEV infection from other flavivirus especially West Nile virus (WNV and Dengue virus (DV infection was greatly hindered for the serological cross-reactive. Virus specific epitopes could benefit for developing JEV specific antibodies detection methods. To identify the JEV specific epitopes, we fully mapped and characterized the continuous B-cell epitope of the PrM/M protein of JEV. Results To map the epitopes on the PrM/M protein, we designed a set of 20 partially overlapping fragments spanning the whole PrM, fused them with GST, and expressed them in an expression vector. Linear epitope M14 (105VNKKEAWLDSTKATRY120 was detected by enzyme-linked immunosorbent assay (ELISA. By removing amino acid residues individually from the carboxy and amino terminal of peptide M14, we confirmed that the minimal unit of the linear epitope of PrM/M was M14-13 (108KEAWLDSTKAT118. This epitope was highly conserved across different JEV strains. Moreover, this epitope did not cross-react with WNV-positive and DENV-positive sera. Conclusion Epitope M14-13 was a JEV specific lineal B-cell epitpe. The results may provide a useful basis for the development of epitope-based virus specific diagnostic clinical techniques.

  17. Travel-acquired Japanese encephalitis and vaccination considerations.

    Science.gov (United States)

    Pavli, Androula; Maltezou, Helena C

    2015-09-27

    Japanese encephalitis (JE) is a serious arboviral disease caused by a virus of the genus Flavivirus. Japanese encephalitis is the most common vaccine-preventable virus causing encephalitis in Asia, affecting more than 50,000 persons and leading to 15,000 fatalities per year in endemic countries. For most travelers to Asia, the risk of Japanese encephalitis infection is extremely low and depends on destination, duration of travel, season, and activities. This article reviews travel-acquired Japanese encephalitis with a focus on epidemiology and prevention in the light of the newly available options for active immunization against Japanese encephalitis which have become available, and of the increasing popularity of travels to Japanese encephalitis endemic countries.

  18. Can we differentiate between herpes simplex encephalitis and Japanese encephalitis?

    Science.gov (United States)

    Kalita, Jayantee; Misra, Usha Kant; Mani, Vinita Elizabeth; Bhoi, Sanjeev Kumar

    2016-07-15

    Herpes simplex encephalitis (HSE) occurs without regional and seasonal predilections. HSE is important to differentiate from arboviral encephalitis in endemic areas because of therapeutic potential of HSE. This study evaluates clinical features, MRI and laboratory findings which may help in differentiating HSE from Japanese encephalitis (JE). Confirmed patients with JE and HSE in last 10years were included. The presenting clinical symptoms including demographic information, seizure, behavioral abnormality, focal weakness and movement disorders were noted. Cranial MRI was done and location and nature of signal alteration were noted. Electroencephalography (EEG), cerebrospinal fluid (CSF), blood counts and serum chemistry were done. Outcome was measured by modified Rankin Scale (mRS). Death, functional outcome and neurological sequelae were noted at 3, 6 and 12months follow up, and compared between HSE and JE. Outcome was categorized as poor (mRS;>2) and good (mRS≤2). 97 patients with JE and 40 HSE were included. JE patients were younger than HSE and occurred in post monsoon period whereas HSE occurred throughout the year. Seizure (86% vs 40%) and behavioral abnormality (48% vs 10%) were commoner in HSE; whereas movement disorders (76% vs 0%) and focal reflex loss (42% vs 10%) were commoner in JE. CSF findings and laboratory parameters were similar in both the groups. Thalamic involvement in JE and temporal involvement in HSE were specific markers of respective encephalitis. Delta slowing on EEG was more frequent in JE than HSE. 20% JE and 30% HSE died in the hospital, and at 1year follow up JE patients showed better outcome compared to HSE (48% vs 24%). Memory loss (72% vs 22%) was the predominant sequelae in HSE. Seizure and behavioral abnormality are common features in HSE whereas focal reflex loss is commoner in JE. In a patient with acute encephalitis, thalamic lesion suggests JE and temporal lobe involvement HSE. Long term outcome in JE is better compared to

  19. Dengue fever virus and Japanese encephalitis virus synthetic peptides, with motifs to fit HLA class I haplotypes prevalent in human populations in endemic regions, can be used for application to skin Langerhans cells to prime antiviral CD8+ cytotoxic T cells (CTLs)--a novel approach to the protection of humans.

    Science.gov (United States)

    Becker, Y

    1994-09-01

    Flaviviruses were reported to induce CD8+ cytotoxic T cells in infected individuals, indicating that nonapeptides, proteolytic cleavage products of the viral precursor protein, enter the endoplasmic reticulum in infected cells and interact with HLA class I molecules. The assembled HLA class I molecules are transported to the plasma membrane and prime CD8+ T cells. Current knowledge of the interaction of viral peptides with HLA molecules is reviewed. Based on this review, an idea is presented to use synthetic flavivirus peptides with an amino acid motif to fit with the HLA class I peptide binding group of HLA haplotypes prevalent in a given population in an endemic area. These synthetic viral peptides may be introduced into the human skin using a lotion containing the peptides ("Peplotion") together with substances capable of enhancing the penetration of these peptides into the skin to reach Langerhans cells. The peptide-treated Langerhans cells, professional antigen-presenting cells, may bind the synthetic viral peptides by their HLA class I peptide-binding grooves. Antigens carrying Langerhans cells are able to migrate and induce the cellular immune response in the lymph nodes. This approach to the priming of antiviral CD8+ cytotoxic T cells may provide cellular immune protection from flavivirus infection without inducing the humoral immune response, which can lead to the shock syndrome in Dengue fever patients. To be able to develop anti-Dengue virus synthetic peptides for populations with different HLA class I haplotypes, it is necessary to develop computational studies to design HLA class I Dengue virus synthetic peptides with motifs to fit the HLA haplotypes of the population living in an endemic region for Dengue fever. Experiments to study Dengue virus and Japanese encephalitis peptides vaccines and their effectiveness in protection against Dengue fever and Japanese encephalitis are needed. The development of human antiviral vaccines for application of viral

  20. The changing epidemiology of Japanese encephalitis and New data: the implications for New recommendations for Japanese encephalitis vaccine.

    Science.gov (United States)

    Connor, Bradley; Bunn, William B

    2017-01-01

    The epidemiology of Japanese Encephalitis and risk to the traveler has changed and continues to evolve. The spread of Japanese Encephalitis virus into new environments, changes in agricultural practice and animal vectors, climate change, peri-urban growth, changes in international travel to Asia, personal risk factors, mosquito vector free transmission, interactions with other flaviviruses and better information on infections without encephalitis and other factors make Japanese Encephalitis an underappreciated risk. There has also been a change in the incidence of Japanese Encephalitis cases that questions the current travel duration and geographic based recommendations. A safe, effective vaccine (Ixiaro) that may be administered in a short course regimen is now available in the United States without the risks of the previous vaccine. However, the vaccine is significantly underutilized. These changes in the epidemiology and new data on the risks of the Japanese Encephalitis virus require a review of the practice guidelines and expert recommendations that do not reflect the current state of knowledge.

  1. Simultaneous detection and differentiation of dengue virus serotypes 1-4, Japanese encephalitis virus, and West Nile virus by a combined reverse-transcription loop-mediated isothermal amplification assay

    Directory of Open Access Journals (Sweden)

    Yin Jianhua

    2011-07-01

    Full Text Available Abstract Background Rapid identification and differentiation of mosquito-transmitted flaviviruses in acute-phase sera of patients and field-caught vector mosquitoes are important for the prediction and prevention of large-scale epidemics. Results We developed a flexible reverse-transcription loop-mediated isothermal amplification (RT-LAMP unit for the detection and differentiation of dengue virus serotypes 1-4 (DENV1-4, Japanese encephalitis virus (JEV, and West Nile virus (WNV. The unit efficiently amplified the viral genomes specifically at wide ranges of viral template concentrations, and exhibited similar amplification curves as monitored by a real-time PCR engine. The detection limits of the RT-LAMP unit were 100-fold higher than that of RT-PCR in 5 of the six flaviviruses. The results on specificity indicated that the six viruses in the assay had no cross-reactions with each other. By examining 66 viral strains of DENV1-4 and JEV, the unit identified the viruses with 100% accuracy and did not cross-react with influenza viruses and hantaviruses. By screening a panel of specimens containing sera of 168 patients and 279 pools of field-caught blood sucked mosquitoes, results showed that this unit is high feasible in clinical settings and epidemiologic field, and it obtained results 100% correlated with real-time RT-PCR. Conclusions The RT-LAMP unit developed in this study is able to quickly detect and accurately differentiate the six kinds of flaviviruses, which makes it extremely feasible for screening these viruses in acute-phase sera of the patients and in vector mosquitoes without the need of high-precision instruments.

  2. Acute hemorrhagic encephalitis: An unusual presentation of dengue viral infection

    Directory of Open Access Journals (Sweden)

    Jeyaseelan Nadarajah

    2015-01-01

    Full Text Available Dengue is a common viral infection worldwide with presentation varying from clinically silent infection to dengue fever, dengue hemorrhagic fever, and severe fulminant dengue shock syndrome. Neurological manifestation usually results from multisystem dysfunction secondary to vascular leak. Presentation as hemorrhagic encephalitis is very rare. Here we present the case of a 13-year-old female admitted with generalized tonic clonic seizures. Plain computed tomography (CT scan of head revealed hypodensities in bilateral deep gray matter nuclei and right posterior parietal lobe without any hemorrhage. Cerebrospinal fluid (CSF and serology were positive for IgM and IgG antibodies to dengue viral antigen. Contrast-enhanced magnetic resonance imaging (MRI revealed multifocal T2 and fluid attenuated inversion recovery (FLAIR hyperintensities in bilateral cerebral parenchyma including basal ganglia. No hemorrhage was seen. She was managed with steroids. As her clinical condition deteriorated, after being stable for 2 days, repeat MRI was done which revealed development of hemorrhage within the lesions, and diagnosis of acute hemorrhagic encephalitis of dengue viral etiology was made.

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

    Science.gov (United States)

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

    2014-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Arnaud Tarantola

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

  5. An SIRS epidemic model of Japanese Encephalitis

    OpenAIRE

    Mukhopadhyay, B. B.; Tapaswi, P. K.

    1994-01-01

    An epidemiological model of the dynamics of Japanese Encephalitis (J.E.) spread coupling the SIRS (Susceptible/Infected/Removal/Susceptible) models of J.E. spread in the reservoir population and in the human population has been proposed. The basic reproductive rate R(0) in the coupled system has been worked out. Using Aron's results (cf. [1] and [2]), it has been observed that the disease-free system is stable in this coupled system also, if R(0) is less than unity, and if R(0) is greater tha...

  6. Current recommendations for the Japanese encephalitis vaccine.

    Science.gov (United States)

    Chen, Hui-Lan; Chang, Jia-Kan; Tang, Ren-Bin

    2015-05-01

    Japanese encephalitis (JE) is a mosquito-borne flavivirus infection and an important cause of encephalitis in most of Asia and parts of the western Pacific. Most people infected with the JE virus (JEV) are asymptomatic or seemingly suffer from a nonspecific, flu-like illness; in others, JE can cause illness ranging from fever and headache to severe encephalitis. Although it can cause significant morbidity and mortality, JE is a vaccine-preventable disease, and vaccination programs have proven most effective in preventing and diminishing the burden of disease. Such JE vaccines have been available for decades with four types of JE vaccines-live attenuated SA14-14-2 vaccine, inactivated mouse brain-derived vaccine (JE-MB), inactivated Vero cell culture vaccine (JE-VC), and live attenuated chimeric vaccine (IMOJEV)-and are currently used in most countries. In some Asian countries such as Japan, China, Taiwan, Korea, and Thailand, immunization programs have been conducted for children and so the ongoing incidence of JE has declined considerably in recent decades. Until quite recently, the primary JE vaccine in use internationally has been the JE-MB, which is now commonly replaced by cell culture-based vaccines. Copyright © 2015. Published by Elsevier Taiwan.

  7. Cortical laminar necrosis in dengue encephalitis-a case report.

    Science.gov (United States)

    Garg, Ravindra Kumar; Rizvi, Imran; Ingole, Rajan; Jain, Amita; Malhotra, Hardeep Singh; Kumar, Neeraj; Batra, Dhruv

    2017-04-20

    Dengue encephalitis is a rare neurological manifestation of dengue fever. Its clinical presentation is similar to other viral encephalitides and encephalopathy. No single specific finding on magnetic resonance imaging of dengue encephalitis has yet been documented. They are highly variable and atypical. A 15-year boy presented with fever, the headache and altered sensorium of 12-day duration. On neurological examination, his Glasgow Coma Scale score was 10 (E3M4V3). There was no focal neurological deficit. Laboratory evaluation revealed leukopenia and marked thrombocytopenia. Dengue virus IgM antibody was positive both in serum and cerebrospinal fluid. Magnetic resonance imaging of the brain revealed signal changes in bilateral parietooccipital and left frontal regions (left hemisphere more involved than the right hemisphere). There was gyriform enhancement bilateral parietooccipital regions consistent with cortical laminar necrosis. Bilaterally diffuse subcortical white matter was also involved and subtle T2 hyperintensity involving both basal ganglia was noted. Gradient echo sequence revealed presence of hemorrhage in the subcortical white matter. Patient was treated conservatively and received platelet transfusion. Patient became fully conscious after 7 days. In a patient with highly suggestive dengue e\\ephalitis, we describe an unusual magnetic resonance imaging finding. This report is possibly the first instance of cortical laminar necrosis in such a setting.

  8. 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.

  9. Japanese Encephalitis: Estimating Future Trends in Asia

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    Julia Metelka

    2015-08-01

    Full Text Available Limited surveillance programs and lack of diagnostic laboratory testing capacity in many low and middle income Asian countries have made it difficult to validate epidemiological patterns and anticipate future changes in disease risk. In this study, we consider the case of Japanese Encephalitis in Asia and examine how populations of human hosts and animal reservoirs are expected to change over the next three decades. Growth was modelled at the sub-national level for rural and urban areas to estimate where high-density, susceptible populations will potentially overlap with populations of the virus' amplifying host. High-risk areas based on these projections were compared to the current distribution of Japanese Encephalitis, and known immunization activities in order to identify areas of highest priority for concern. Results indicated that mapping JE risk factors at the sub-national level is an effective way to contextualize and supplement JE surveillance data. New patterns of risk factor change occurring in Southeast Asia were identified, including around major urban areas experiencing both urbanization and growth in pig populations. A hotspot analysis of pig-to-population ratio found a significant spatial cluster extending northward through Southeast Asia and interior China. Mapping forecasted changes in risk factors for JE highlights regions vulnerable to emerging zoonoses and may be an important tool for developing effecting transnational health policies.

  10. Japanese encephalitis: the virus and vaccines.

    Science.gov (United States)

    Yun, Sang-Im; Lee, Young-Min

    2014-01-01

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

  11. The Involvement of Microglial Cells in Japanese Encephalitis Infections

    Science.gov (United States)

    Thongtan, Thananya; Thepparit, Chutima; Smith, Duncan R.

    2012-01-01

    Despite the availability of effective vaccines, Japanese encephalitis virus (JEV) infections remain a leading cause of encephalitis in many Asian countries. The virus is transmitted to humans by Culex mosquitoes, and, while the majority of human infections are asymptomatic, up to 30% of JE cases admitted to hospital die and 50% of the survivors suffer from neurological sequelae. Microglia are brain-resident macrophages that play key roles in both the innate and adaptive immune responses in the CNS and are thus of importance in determining the pathology of encephalitis as a result of JEV infection. PMID:22919405

  12. [A Case of Clinically Mild Encephalitis/encephalopathy with a Reversible Splenial Lesion due to Dengue Fever].

    Science.gov (United States)

    Saito, Nobuo; Kitashouji, Emi; Kojiro, Maiko; Furumoto, Akitugu; Morimoto, Konosuke; Morita, Kouichi; Ariyoshi, Koya

    2015-07-01

    Clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) has been recently proposed as a clinical-radiological syndrome. Several causes of MERS have been reported including infectious diseases. We present herein on a case of MERS induced by dengue fever in a Japanese traveler. A 48-year-old male returning from Thailand and Cambodia was admitted for an unknown fever. Following admission, the dengue virus was diagnosed with a positive RT-PCR result. On day 5 of the illness, regardless of reduced fever, weakness suddenly developed in both upper limbs. A cerebral MRI showed hyperintensities in the splenium of the corpus callosum on T2-weighted and diffusion-weighted images. The symptoms resolved completely within two days of onset. The patient was diagnosed as having MERS due to the MRI features and the mild clinical course. Although only a few cases of MERS caused by dengue fever have been reported, the condition is possibly underdiagnosed. It is hypothesized that dengue fever can induce MERS as dengue fever can cause increased endothelium permeability and hypo-sodium which have been proposed in the pathogenesis of MERS. However, there is currently limited evidence for this. Further research is recommended to demonstrate a causal association between dengue fever and MERS.

  13. Development of a vaccine to prevent Japanese encephalitis: a brief review

    OpenAIRE

    Viroj Wiwanitkit

    2009-01-01

    Viroj WiwanitkitWiwanitkit House, Bangkhae, Bangkok, ThailandAbstract: Japanese encephalitis (ICD 10: A83.0) is an important specific viral encephalitis caused by the Japanese encephalitis virus, a virus of the Flavivirus group. Millions of people, especially those in endemic areas of developing countries in Asia, are at high risk from this infection. Therefore proper management to deal with this virus is essential. There is no specific treatment for Japanese encephalitis virus. Supportive an...

  14. Concurrent infection of Japanese encephalitis and mixed plasmodium infection

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    Girish Chandra Bhatt

    2012-01-01

    Full Text Available Japanese encephalitis (JE and malaria would coexist in the areas where both illnesses are endemic with overlapping clinical pictures, especially in a case of febrile encephalopathy with hepatosplenomegaly. However, there are no published data till date showing concurrent infection of these two agents despite both diseases being coendemic in many areas. We report a case of concurrent infection of JE and mixed plasmodium infection, where the case, initially diagnosed as cerebral malaria did not improve on antimalarials and alternative diagnosis of JEV encephalitis was thought which was confirmed by a serological test. To the best of our knowledge, this is the first case report of concurrent Japanese encephalitis with mixed plasmodium infection. We report a case of 3-year-old male child, who presented with febrile encephalopathy with hepatosplenomegaly. Based on a rapid diagnostic test and peripheral smear examination, a diagnosis of mixed P.Vivax and P.falciparum infection was made and the patient was treated with quinine and doxycycline. However, besides giving antimalarials the patient did not improve and an alternative diagnosis of JE was considered as the patient was from the endemic zone of Japanese encephalitis. Cerebrospinal fluid (CSF of the patient was sent for a virological study which came out to be positive for JE IgM in CSF, which is confirmatory of JE infection. In a patient with febrile encephalopathy with hepatosplenomegaly especially in areas coendemic for JE and malaria, the possibility of mixed infection should be kept in mind.

  15. Epidemiology of Japanese encephalitis: past, present, and future prospects

    Science.gov (United States)

    Wang, Huanyu; Liang, Guodong

    2015-01-01

    Japanese encephalitis (JE) is one of severe viral encephalitis that affects individuals in Asia, western Pacific countries, and northern Australia. Although 67,900 JE cases have been estimated among 24 JE epidemic countries annually, only 10,426 have been reported in 2011. With the establishment of JE surveillance and vaccine use in some countries, the JE incidence rate has decreased; however, serious outbreaks still occur. Understanding JE epidemics and identifying the circulating JE virus genotypes will improve JE prevention and control. This review summarizes the current epidemiology data in these countries. PMID:25848290

  16. Production of single-round infectious chimeric flaviviruses with DNA-based Japanese encephalitis virus replicon.

    Science.gov (United States)

    Suzuki, Ryosuke; Ishikawa, Tomohiro; Konishi, Eiji; Matsuda, Mami; Watashi, Koichi; Aizaki, Hideki; Takasaki, Tomohiko; Wakita, Takaji

    2014-01-01

    A method for rapid production of single-round infectious particles (SRIPs) of flavivirus would be useful for viral mutagenesis studies. Here, we established a DNA-based production system for SRIPs of flavivirus. We constructed a Japanese encephalitis virus (JEV) subgenomic replicon plasmid, which lacked the C-prM-E (capsid-pre-membrane-envelope) coding region, under the control of the cytomegalovirus promoter. When the JEV replicon plasmid was transiently co-transfected with a JEV C-prM-E expression plasmid into 293T cells, SRIPs were produced, indicating successful trans-complementation with JEV structural proteins. Equivalent production levels were observed when C and prM-E proteins were provided separately. Furthermore, dengue types 1-4, West Nile, yellow fever or tick-borne encephalitis virus prM-E proteins could be utilized for production of chimaeric flavivirus SRIPs, although the production was less efficient for dengue and yellow fever viruses. These results indicated that our plasmid-based system is suitable for investigating the life cycles of flaviviruses, diagnostic applications and development of safer vaccine candidates.

  17. Epidemiology of Japanese encephalitis in the Philippines: a systematic review.

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    Anna Lena Lopez

    2015-03-01

    Full Text Available Japanese encephalitis virus (JEV is an important cause of encephalitis in most of Asia, with high case fatality rates and often significant neurologic sequelae among survivors. The epidemiology of JE in the Philippines is not well defined. To support consideration of JE vaccine for introduction into the national schedule in the Philippines, we conducted a systematic literature review and summarized JE surveillance data from 2011 to 2014.We conducted searches on Japanese encephalitis and the Philippines in four databases and one library. Data from acute encephalitis syndrome (AES and JE surveillance and from the national reference laboratory from January 2011 to March 2014 were tabulated and mapped.We identified 29 published reports and presentations on JE in the Philippines, including 5 serologic surveys, 18 reports of clinical cases, and 8 animal studies (including two with both clinical cases and animal data. The 18 clinical studies reported 257 cases of laboratory-confirmed JE from 1972 to 2013. JE virus (JEV was the causative agent in 7% to 18% of cases of clinical meningitis and encephalitis combined, and 16% to 40% of clinical encephalitis cases. JE predominantly affected children under 15 years of age and 6% to 7% of cases resulted in death. Surveillance data from January 2011 to March 2014 identified 73 (15% laboratory-confirmed JE cases out of 497 cases tested.This comprehensive review demonstrates the endemicity and extensive geographic range of JE in the Philippines, and supports the use of JE vaccine in the country. Continued and improved surveillance with laboratory confirmation is needed to systematically quantify the burden of JE, to provide information that can guide prioritization of high risk areas in the country and determination of appropriate age and schedule of vaccine introduction, and to measure the impact of preventive measures including immunization against this important public health threat.

  18. Epidemiology of Japanese encephalitis in the Philippines: a systematic review.

    Science.gov (United States)

    Lopez, Anna Lena; Aldaba, Josephine G; Roque, Vito G; Tandoc, Amado O; Sy, Ava Kristy; Espino, Fe Esperanza; DeQuiroz-Castro, Maricel; Jee, Youngmee; Ducusin, Maria Joyce; Fox, Kimberley K

    2015-03-01

    Japanese encephalitis virus (JEV) is an important cause of encephalitis in most of Asia, with high case fatality rates and often significant neurologic sequelae among survivors. The epidemiology of JE in the Philippines is not well defined. To support consideration of JE vaccine for introduction into the national schedule in the Philippines, we conducted a systematic literature review and summarized JE surveillance data from 2011 to 2014. We conducted searches on Japanese encephalitis and the Philippines in four databases and one library. Data from acute encephalitis syndrome (AES) and JE surveillance and from the national reference laboratory from January 2011 to March 2014 were tabulated and mapped. We identified 29 published reports and presentations on JE in the Philippines, including 5 serologic surveys, 18 reports of clinical cases, and 8 animal studies (including two with both clinical cases and animal data). The 18 clinical studies reported 257 cases of laboratory-confirmed JE from 1972 to 2013. JE virus (JEV) was the causative agent in 7% to 18% of cases of clinical meningitis and encephalitis combined, and 16% to 40% of clinical encephalitis cases. JE predominantly affected children under 15 years of age and 6% to 7% of cases resulted in death. Surveillance data from January 2011 to March 2014 identified 73 (15%) laboratory-confirmed JE cases out of 497 cases tested. This comprehensive review demonstrates the endemicity and extensive geographic range of JE in the Philippines, and supports the use of JE vaccine in the country. Continued and improved surveillance with laboratory confirmation is needed to systematically quantify the burden of JE, to provide information that can guide prioritization of high risk areas in the country and determination of appropriate age and schedule of vaccine introduction, and to measure the impact of preventive measures including immunization against this important public health threat.

  19. Recent advances in Japanese encephalitis [version 1; referees: 4 approved

    Directory of Open Access Journals (Sweden)

    Anirban Basu

    2017-03-01

    Full Text Available Japanese encephalitis is a flaviviral disease that is endemic to the South, Southeast Asia, and Asia Oceania regions. Given that about 60% of the world’s population (about 7.4 billion resides in this region (about 4.4 billion, this disease poses a significant threat to global health. Active vaccination campaigns conducted in endemic countries have led to a decrease in the number of reported cases over the years. In this article, we strive to briefly highlight recent advances in understanding the role of microRNAs in disease pathology, focus on providing brief summaries of recent clinical trials in the field of Japanese encephalitis therapeutics, and review the current prophylactic strategies.

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

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    Gao Xiaoyan

    2010-11-01

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

  1. Dengue encephalitis with predominant cerebellar involvement: Report of eight cases with MR and CT imaging features

    Energy Technology Data Exchange (ETDEWEB)

    Hegde, Vinay; Bhat, Maya; Prasad, Chandrajit; Gupta, A.K.; Saini, Jitender [National Institute of Mental Health and Neurosciences, Department of Neuroimaging and Interventional Radiology, Bangalore, Karnataka (India); Aziz, Zarina [Sri Sathya Sai Institute of Medical Science, Department of Radiology, Bangalore (India); Kumar, Sharath [Apollo Hospital, Department of Neuroradiology, Bangalore (India); Netravathi, M. [National Institute of Mental Health and Neurosciences, Department of Neurology, Bangalore (India)

    2014-11-01

    CNS dengue infection is a rare condition and the pattern of brain involvement has not been well described. We report the MR imaging (MRI) features in eight cases of dengue encephalitis. We retrospectively searched cases of dengue encephalitis in which imaging was performed. Eight cases (three men, five women; age range: 8-42 years) diagnosed with dengue encephalitis were included in the study. MR studies were performed on 3-T and 1.5-T MR clinical systems. Two neuroradiologists retrospectively reviewed the MR images and analysed the type of lesions, as well as their distribution and imaging features. All eight cases exhibited MRI abnormalities and the cerebellum was involved in all cases. In addition, MRI signal changes were also noted in the brainstem, thalamus, basal ganglia, internal capsule, insula, mesial temporal lobe, and cortical and cerebral white matter. Areas of susceptibility, diffusion restriction, and patchy post-contrast enhancement were the salient imaging features in our cohort of cases. A pattern of symmetrical cerebellar involvement and presence of microbleeds/haemorrhage may serve as a useful imaging marker and may help in the diagnosis of dengue encephalitis. (orig.)

  2. Detection of Saint Louis encephalitis virus in dengue-suspected cases during a dengue 3 outbreak.

    Science.gov (United States)

    Terzian, Ana Carolina Bernardes; Mondini, Adriano; Bronzoni, Roberta Vieira de Moraes; Drumond, Betânia Paiva; Ferro, Bianca Piovezan; Cabrera, Eliana Márcia Sotello; Figueiredo, Luis Tadeu Moraes; Chiaravalloti-Neto, Francisco; Nogueira, Maurício Lacerda

    2011-03-01

    Arboviruses are frequently associated with outbreaks in humans and represent a serious public health problem. Among the Brazilian arboviruses, Mayaro virus, Dengue virus (DENV), Yellow Fever virus, Rocio virus, Saint Louis Encephalitis virus (SLEV), and Oropouche virus are responsible for most of human cases. All these arboviruses usually produce undistinguishable acute febrile illness, especially in the acute phase of infection. In this study we investigated the presence of arboviruses in sera of 519 patients presenting acute febrile illness, during a dengue outbreak in São José do Rio Preto City (São Paulo, Brazil). A multiplex-nested RT-polymerase chain reaction assay was applied to detect and identify the main Brazilian arboviruses (Flavivirus, Alphavirus, and Orthobunyavirus genera). The molecular analysis showed that 365 samples were positive to DENV-3, 5 to DENV-2, and 8 to SLEV. Among the positive samples, one coinfection was detected between DENV-2 and DENV-3. The phylogenetic analysis of the SLEV envelope gene indicated that the virus circulating in city is related to lineage V strains. These results indicated that during that large DENV-3 outbreak in 2006, different arboviruses cocirculated causing human disease. Thus, it is necessary to have an efficient surveillance system to control the dissemination of these arboviruses in the population.

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

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    Szu-Ting Chen

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

  4. Control of Japanese encephalitis in Asia: the time is now.

    Science.gov (United States)

    Hills, Susan; Martin, Rebecca; Marfin, Anthony; Fischer, Marc

    2014-08-01

    Japanese encephalitis (JE) virus is the most common vaccine-preventable cause of encephalitis in Asia. Recent progress in the development and availability of improved JE vaccines has revitalized the prospects for JE control. There now are a number of safe and effective vaccines, two WHO prequalified vaccines available for pediatric use, at least one vaccine considered affordable for use in lower income countries, and a GAVI Alliance commitment to provide financial support to eligible countries for campaigns for children aged 9 months through 14 years. While challenges remain, this tremendous progress means there is a better opportunity than at any time in the past to prevent the substantial morbidity and mortality from this disease.

  5. Human T cell responses to Japanese encephalitis virus in health and disease.

    Science.gov (United States)

    Turtle, Lance; Bali, Tanushka; Buxton, Gemma; Chib, Savita; Chan, Sajesh; Soni, Mohammed; Hussain, Mohammed; Isenman, Heather; Fadnis, Prachi; Venkataswamy, Manjunatha M; Satishkumar, Vishali; Lewthwaite, Penny; Kurioka, Ayako; Krishna, Srinivasa; Shankar, M Veera; Ahmed, Riyaz; Begum, Ashia; Ravi, Vasanthapuram; Desai, Anita; Yoksan, Sutee; Fernandez, Stefan; Willberg, Christian B; Kloverpris, Henrik N; Conlon, Christopher; Klenerman, Paul; Satchidanandam, Vijaya; Solomon, Tom

    2016-06-27

    Japanese encephalitis (JE) virus (JEV) is an important cause of encephalitis in children of South and Southeast Asia. However, the majority of individuals exposed to JEV only develop mild symptoms associated with long-lasting adaptive immunity. The related flavivirus dengue virus (DENV) cocirculates in many JEV-endemic areas, and clinical data suggest cross-protection between DENV and JEV. To address the role of T cell responses in protection against JEV, we conducted the first full-breadth analysis of the human memory T cell response using a synthetic peptide library. Ex vivo interferon-γ (IFN-γ) responses to JEV in healthy JEV-exposed donors were mostly CD8(+) and targeted nonstructural (NS) proteins, whereas IFN-γ responses in recovered JE patients were mostly CD4(+) and targeted structural proteins and the secreted protein NS1. Among patients, a high quality, polyfunctional CD4(+) T cell response was associated with complete recovery from JE. T cell responses from healthy donors showed a high degree of cross-reactivity to DENV that was less apparent in recovered JE patients despite equal exposure. These data reveal divergent functional CD4(+) and CD8(+) T cell responses linked to different clinical outcomes of JEV infection, associated with distinct targeting and broad flavivirus cross-reactivity including epitopes from DENV, West Nile, and Zika virus.

  6. Field Evaluation of a Deployable RT-PCR Assay System for Real-Time Identification of Dengue Virus

    Science.gov (United States)

    2004-06-01

    strains of dengue serotypes 1-4, yellow fever, Japanese encephalitis, West Nile, and St. Louis encephalitis viruses as well as dengue virus infected...JA, Pyke A, Smith GA. Single rapid TaqMan fluorogenic probe based PCR assay that detects all four dengue serotypes . J Med Virol. 2002 April; 66(4

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

    Science.gov (United States)

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

    2017-09-01

    Japanese encephalitis (JE) is a major public health concern in Asia and poses a small but potentially fatal threat to travelers from nonendemic countries, including children. No JE vaccine for pediatric use has been available in Europe and the United States. Age-stratified cohorts of children between 2 months and 17 years received 2 doses of Vero cell-derived inactivated JE virus vaccine (IXIARO; Valneva Austria GmbH, Vienna, Austria) administered 28 days apart [99% of subjects who received the age-appropriate dose.

  8. Incidence of Japanese Encephalitis among Acute Encephalitis Syndrome Cases in West Bengal, India

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    Bhaswati Bandyopadhyay

    2013-01-01

    Full Text Available Background and Objectives. Japanese encephalitis (JE is the most important cause of acute and epidemic viral encephalitis. Every year sporadic JE cases are reported from the various districts of West Bengal, indicating its endemicity in this state. JE vaccination programme has been undertaken by the State Health Department of West Bengal. This study was aimed at seeing the present scenario of JE among acute encephalitis syndrome (AES cases in West Bengal. Materials and Methods. Blood and/or CSF samples were referred from suspected AES cases to the referral virology laboratory of the Calcutta School of Tropical Medicine from different hospitals of Kolkata. IgM antibody capture ELISA was performed on the CSF and serum samples by JE virus MAC ELISA kit supplied by the National Institute of Virology, Pune. Results. The present study reveals that 22.76% and 5% of the AES cases were positive for JE IgM in 2011 and 2012, respectively. JE is mainly prevalent in children and adolescents below 20 years of age with no gender predilection. Although the percentages of JE positive cases were high in 2011, it sharply decreased thereafter possibly due to better awareness programs, due to mass vaccination, or simply due to natural epidemiological niche periodicity due to herd immunity.

  9. The Potential Use of Wolbachia-Based Mosquito Biocontrol Strategies for Japanese Encephalitis.

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    Claire L Jeffries

    Full Text Available Japanese encephalitis virus (JEV is a zoonotic pathogen transmitted by the infectious bite of Culex mosquitoes. The virus causes the development of the disease Japanese encephalitis (JE in a small proportion of those infected, predominantly affecting children in eastern and southern Asia. Annual JE incidence estimates range from 50,000-175,000, with 25%-30% of cases resulting in mortality. It is estimated that 3 billion people live in countries in which JEV is endemic. The virus exists in an enzootic transmission cycle, with mosquitoes transmitting JEV between birds as reservoir hosts and pigs as amplifying hosts. Zoonotic infection occurs as a result of spillover events from the main transmission cycle. The reservoir avian hosts include cattle egrets, pond herons, and other species of water birds belonging to the family Ardeidae. Irrigated rice fields provide an ideal breeding ground for mosquitoes and attract migratory birds, maintaining the transmission of JEV. Although multiple vaccines have been developed for JEV, they are expensive and require multiple doses to maintain efficacy and immunity. As humans are a "dead-end" host for the virus, vaccination of the human population is unlikely to result in eradication. Therefore, vector control of the principal mosquito vector, Culex tritaeniorhynchus, represents a more promising strategy for reducing transmission. Current vector control strategies include intermittent irrigation of rice fields and space spraying of insecticides during outbreaks. However, Cx. Tritaeniorhynchus is subject to heavy exposure to pesticides in rice fields, and as a result, insecticide resistance has developed. In recent years, significant advancements have been made in the potential use of the bacterial endosymbiont Wolbachia for mosquito biocontrol. The successful transinfection of Wolbachia strains from Drosophila flies to Aedes (Stegomyia mosquitoes has resulted in the generation of "dengue-refractory" mosquito

  10. A case of sudden death after Japanese encephalitis vaccination.

    Science.gov (United States)

    Bunai, Yasuo; Ishii, Akira; Akaza, Kayoko; Nagai, Atsushi; Nishida, Naoki; Yamaguchi, Seiji

    2015-07-01

    Japanese encephalitis (JE) virus is estimated to result in 3500-50,000 clinical cases every year, with mortality rates of up to 20-50% and a high percentage of neurological sequelae in survivors. Vaccination is the single most important measure in preventing this disease. Inactivated Vero cell culture-derived JE vaccines have not been linked to any fatalities, and few serious adverse events after vaccination have been reported. Here, we report a case of sudden death in which a 10-year-old boy experienced cardiopulmonary arrest 5 min after receiving a Japanese encephalitis vaccination. He had been receiving psychotropic drugs for the treatment of pervasive developmental disorders. Postmortem examinations were nonspecific, and no signs of dermatologic or mucosal lesions or an elevation of the serum tryptase level, which are characteristic of anaphylaxis, were observed. A toxicological examination revealed that the blood concentrations of the orally administered psychotropic drugs were within the therapeutic ranges. The patient was considered to have died of an arrhythmia that was not directly associated with the vaccination. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  11. Development of a vaccine to prevent Japanese encephalitis: a brief review

    Science.gov (United States)

    Wiwanitkit, Viroj

    2009-01-01

    Japanese encephalitis (ICD 10: A83.0) is an important specific viral encephalitis caused by the Japanese encephalitis virus, a virus of the Flavivirus group. Millions of people, especially those in endemic areas of developing countries in Asia, are at high risk from this infection. Therefore proper management to deal with this virus is essential. There is no specific treatment for Japanese encephalitis virus. Supportive and symptomatic treatments are usually used, which emphasize the importance of prevention in this specific neurological disorder. Vector control or vaccination can be used to prevent the disease. Because the existing Japanese encephalitis vaccine poses some undesirable problems, a new vaccine is needed. The process of developing a new vaccine is briefly discussed. PMID:20360904

  12. Japanese encephalitis in two children--United States, 2010.

    Science.gov (United States)

    2011-03-11

    Japanese encephalitis virus (JEV) is the leading cause of vaccine-preventable encephalitis in Asia and the western Pacific. JEV is maintained in an enzootic cycle involving mosquitoes and amplifying vertebrate hosts, mainly pigs and wading birds. The virus is transmitted to humans primarily by Culex mosquitoes, which breed in flooded rice fields and pools of stagnant water and most often feed outdoors during the evening and night. JEV transmission occurs mainly in rural agricultural areas, but occasional human cases occur in urban areas. Japanese encephalitis (JE) in persons who have traveled or lived overseas is diagnosed infrequently in the United States, with only four cases identified from 1992 (when a JE vaccine was first licensed in the United States) to 2008. This report describes the only cases diagnosed in the United States and reported to CDC since then. The first was a fatal case in a U.S. child who had visited relatives in the Philippines. The other occurred in a refugee who became ill while traveling from Thailand to the United States and whose diagnosis was complicated by concurrent neurocysticercosis. JE should be considered in the differential diagnosis for any patient with an acute neurologic infection who recently has been in a JE-endemic country. Travelers to JE-endemic countries should be advised of the risk for JE and the importance of personal protective measures to prevent mosquito bites. JE vaccine should be considered for travelers who might be at greater risk based on the season, location, and duration of their visit and their planned activities.

  13. A retrospective survey of dengue fever among Japanese individuals staying in Manila, Philippines.

    Science.gov (United States)

    Hamada, Atsuo; Tada, Yuki; Fukushima, Shinji; Murata, Hidemi; Kikuchi, Hirohisa

    2016-01-01

    Dengue fever is a serious concern for Japanese people staying in Southeast Asia. In order to implement necessary prophylactic measures for dengue fever in this population, we investigated the characteristics of dengue fever among Japanese nationals living in Manila, Philippines. From 2012 to 2015, 175 Japanese expatriates were diagnosed with dengue fever at the medical clinic of the Japanese Association Manila, Inc. Most of the patients were employees of Japanese companies and their families and were long-term residents of Manila. Most patients were either dengue fever were reported. The reported number of patients with dengue fever has shown a decreasing trend: from 55 cases in 2012 to 53 in 2013, 31 in 2014, and 36 in 2015. The results of this survey could be useful for the development of effective dengue fever preventive measures such as health education and provision of information among not only Japanese but also other foreigners residing in endemic areas.

  14. Crystal Structure of the Japanese Encephalitis Virus Envelope Protein

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-03-13

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

  15. DETECTION OF A NEUTROPHIL CHEMOTACTIC FACTOR IN JAPANESE ENCEPHALITIS PATIENTS

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    Aditi Singh

    2012-12-01

    Full Text Available Japanese encephalitis (JE one of the most common cause of acute encephalitis in tropical regions, has generated much public anxiety in India. An early influx of macrophages followed by neutrophils at the site of injury in different organs in humans and mice has previously been reported. It correlated with production of a neutrophil chemotactic protein derived from macrophages. In the present study out of a total of 324 acute encephalitic patients, admitted in Gandhi memorial and associated hospitals, Lucknow, 121 patients with one or more indicators of JE virus infection were included. Significant pleocytosis (mean TLC value of 126+52 cells / mm3 in CSF and leucocytosis (>11,000 cells/mm3 in peripheral blood was observed at the time of admission. The leucocytosis increased significantly during second week in 67% of patients. The peripheral blood mononuclear cells culture done on alternate days was tested for chemotactic activity (hMDF, which was observed to be highest in second week of illness. The direct detection of hMDF in circulation by dot blot was positive in 92% of acute serum samples, with negligible (12.5% reactivity for convalescent sera. A correlation between the hMDF levels and severity of illness has also been observed.

  16. Disability from Japanese encephalitis in Cambodia and Viet Nam.

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    Hills, Susan L; Van Cuong, Nguyen; Touch, Sok; Mai, Hoang Hong; Soeung, Sann Chan; Lien, Tran Thi Huong; Samnang, Chham; Sovann, Ly; Van Diu, Pham; Lac, Luc Duy; Heng, Seng; Huong, Vu Minh; Grundy, John J; Huch, Chea; Lewthwaite, Penny; Solomon, Tom; Jacobson, Julie A

    2011-08-01

    A cohort of Japanese encephalitis (JE) survivors in Cambodia and Viet Nam were assessed at least 4 months after hospital discharge in order to understand the extent of disability after JE. We used a simple assessment tool which focuses on the impact on daily life. In total, 64 disability assessments were conducted: 38 in Cambodia and 26 in Viet Nam. In Cambodia, 4 (11%) children had severe sequelae, suggesting the children would likely be dependent, 15 (39%) had moderate sequelae and 17 (45%) had mild sequelae. In Viet Nam, two (8%) persons had severe sequelae, five (19%) had moderate sequelae and eight (31%) had mild sequelae. In many JE-endemic areas there are no multi-disciplinary teams with sophisticated equipment to assess patients after JE disease. This assessment tool can assist with patient management and generate data to support the need for programmes to prevent disease and improve outcomes for survivors.

  17. Japanese encephalitis: Challenges and intervention opportunities in Nepal

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    Shristi Ghimire

    2015-01-01

    Full Text Available Japanese encephalitis (JE is a mosquito borne zoonotic disease caused by JE virus (JEV. JE has been endemic in Terai region, the lowland plains of Nepal bordering India, since 1978. However, in recent years cases of JE has been continuously reported from high altitude zones of hills and mountains. Irrigated rice farming system, expanded pig husbandry practices, inadequate vaccine coverage, low level of public awareness and climate change favoring mosquito breeding in higher altitudes might be the probable risk factors for emergence and re-emergence of JE in Nepal. Repeated outbreak in endemic areas and geographical expansion to newer areas have created huge challenge for JE prevention and control. At present, JE is one of the major public health concern of Nepal. Expanding vaccine coverage, improving agricultural practices, generating public awareness, supporting for use of mosquito avoiding practices and regional collaboration at border against JE can be helpful in getting better control over it in future.

  18. Japanese Encephalitis Vaccines: WHO position paper, February 2015--Recommendations.

    Science.gov (United States)

    2016-01-12

    This article presents the World Health Organization's (WHO) recommendations on the use of Japanese Encephalitis (JE) vaccines excerpted from the WHO position paper on Japanese Encephalitis vaccines recently published in the Weekly Epidemiological Record [1]. This updated position paper on JE vaccines replaces the 2006 position paper on this subject [2]; it focuses on new information concerning the availability, safety, immunogenicity and effectiveness of JE vaccines and the duration of protection they confer. Recent data on global prevalence and burden of disease caused by JE and cost-effectiveness considerations regarding JE vaccination are also summarized. Footnotes to this paper provide a number of core references including references to grading tables that assess the quality of the scientific evidence. In accordance with its mandate to provide guidance to Member States on health policy matters, WHO issues a series of regularly updated position papers on vaccines and combinations of vaccines against diseases that have an international public health impact. These papers are concerned primarily with the use of vaccines in large-scale immunization programmes; they summarize essential background information on diseases and vaccines, and conclude with WHO's current position on the use of vaccines in the global context. This paper reflects the recommendations of WHO's Strategic Advisory Group of Experts (SAGE) on immunization. These recommendations were discussed by SAGE at its October 2014 meeting. Evidence presented at the meeting can be accessed at http://www.who.int/immunization/sage/previous/en/index.html. Copyright © 2015 The World Health Organization. Published by Elsevier Ltd.. All rights reserved.

  19. Japanese encephalitis can trigger anti-N-methyl-D-aspartate receptor encephalitis.

    Science.gov (United States)

    Ma, Jiannan; Zhang, Ting; Jiang, Li

    2017-06-01

    Japanese encephalitis (JE) is usually a monophasic disease; however, in rare cases, patients with JE may have an early relapse after a partial recovery, giving rise to a biphasic pattern for the disease. In this study, we report three pediatric cases in which post-JE relapse was characterized by movement disorder and/or behavioral problems, and was related to anti-N-methyl-D-aspartate receptor (NMDAR) immunoglobulin G (IgG). Serum and cerebrospinal fluid were examined for anti-NMDAR IgG in three patients who had confirmed JE and then developed relapsing symptoms which were similar to those of anti-NMDAR encephalitis. The main symptoms of the two young children were choreoathetosis, irritability, and sleep disorder; while for the teenager, agitation, mutism, rigidity, and sleep disorder were the main symptoms. Samples of cerebrospinal fluid from all patients were positive for anti-NMDAR IgG, and all patients gradually improved with immunotherapy. Testing for NMDAR antibodies is highly recommend in patients with JE, especially those with a relapsing syndrome involving movement disorder and/or behavioral problems, as these patients may benefit from immunotherapy.

  20. Data from the world health organization (WHO national network laboratory for japanese encephalitis

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    A K Borthakur

    2013-01-01

    Full Text Available Aim: Japanese encephalitis (JE virus is the leading cause of viral neurologic disease and disability in Asia. In the present study JE virus-specific IgM in serum and CSF from acute encephalitis syndrome (AES patients, attending Assam Medical College and Hospital (AMC and H, Dibrugarh, Assam from 2007 to 2009 were detected and different epidemiological parameters namely age, season and vaccination campaign were enumerated. Materials and Methods: A cross-sectional study on patients with AES admitted in AMC and H, Dibrugarh, Assam was done during 2007 to 2009. The different epidemiological features were characterized depending on a pretested structured questionnaire called the clinical information form (CIF. Serum and CSF obtained were tested by a Panbio JE-Dengue IgM Combo ELISA kit and JEV Chex kit (Xycton. Statistical Analysis: A z-test was used for the statistical analytic assessment. Results: Detection rate of JE was 39.4%, 51.1%, and 51.3% in the years 2007, 2008, and 2009 respectively. Cases of JE increased in the age group more than 15 years in the district where the vaccination program was undertaken. This increase of cases from pediatric to adults is also statistically significant by the z-test (P<0.05. Conclusion: There was an increase in AES cases and also JE cases from 2007 to 2009. JE also showed a seasonal variation with maximum cases in the months of July and August. Although vaccination campaigns with the live attenuated vaccine SA-14-14-2 have started and are protecting the under-15 children, there is a shift of disease pattern in the older population.

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

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    Amy J Schuh

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

  2. Neuropathogenesis of Japanese encephalitis in a primate model.

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    Khin Saw Aye Myint

    2014-08-01

    Full Text Available Japanese encephalitis (JE is a major cause of mortality and morbidity for which there is no treatment. In addition to direct viral cytopathology, the inflammatory response is postulated to contribute to the pathogenesis. Our goal was to determine the contribution of bystander effects and inflammatory mediators to neuronal cell death.Material from a macaque model was used to characterize the inflammatory response and cytopathic effects of JE virus (JEV. Intranasal JEV infection induced a non-suppurative encephalitis, dominated by perivascular, infiltrates of mostly T cells, alongside endothelial cell activation, vascular damage and blood brain barrier (BBB leakage; in the adjacent parenchyma there was macrophage infiltration, astrocyte and microglia activation. JEV antigen was mostly in neurons, but there was no correlation between intensity of viral infection and degree of inflammatory response. Apoptotic cell death occurred in both infected and non-infected neurons. Interferon-α, which is a microglial activator, was also expressed by both. Tumour Necrosis Factor-α, inducible nitric oxide synthase and nitrotyrosine were expressed by microglial cells, astrocytes and macrophages. The same cells expressed matrix metalloproteinase (MMP-2 whilst MMP-9 was expressed by neurons.The results are consistent with JEV inducing neuronal apoptotic death and release of cytokines that initiate microglial activation and release of pro-inflammatory and apoptotic mediators with subsequent apoptotic death of both infected and uninfected neurons. Activation of astrocytes, microglial and endothelial cells likely contributes to inflammatory cell recruitment and BBB breakdown. It appears that neuronal apoptotic death and activation of microglial cells and astrocytes play a crucial role in the pathogenesis of JE.

  3. Inhibition of Japanese Encephalitis Virus Infection by Flavivirus Recombinant E Protein Domain Ⅲ

    Institute of Scientific and Technical Information of China (English)

    Jingjing Fan; Yi Liu; Xuping Xie; Bo Zhang; Zhiming Yuan

    2013-01-01

    Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus closely related to the human pathogens including yellow fever virus,dengue virus and West Nile virus.There are currently no effective antiviral therapies for all of the flavivirus and only a few highly effective vaccines are licensed for human use.In this paper,the E protein domain Ⅲ (DⅢ) of six heterologous flaviviruses (DENV1-4,WNV and JEV) was expressed in Escherichia coli successfully.The proteins were purified after a solubilization and refolding procedure,characterized by SDS-PAGE and Western blotting.Competitive inhibition showed that all recombinant flavivirus DⅢ proteins blocked the entry of JEV into BHK-21 cells.Further studies indicated that antibodies induced by the soluble recombinant flavivirus DⅢ partially protected mice against lethal JEV challenge.These results demonstrated that recombinant flavivirus DⅢ proteins could inhibit JEV infection competitively,and immunization with proper folding flavivirus DⅢ induced cross-protection against JEV infection in mice,implying a possible role of DⅢ for the cross-protection among flavivirus as well as its use in antigens for immunization in animal models.

  4. Comparative spatial dynamics of Japanese encephalitis and acute encephalitis syndrome in Nepal.

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    Colin Robertson

    Full Text Available Japanese Encephalitis (JE is a vector-borne disease of major importance in Asia. Recent increases in cases have spawned the development of more stringent JE surveillance. Due to the difficulty of making a clinical diagnosis, increased tracking of common symptoms associated with JE-generally classified as the umbrella term, acute encephalitis syndrome (AES has been developed in many countries. In Nepal, there is some debate as to what AES cases are, and how JE risk factors relate to AES risk. Three parts of this analysis included investigating the temporal pattern of cases, examining the age and vaccination status patterns among AES surveillance data, and then focusing on spatial patterns of risk factors. AES and JE cases from 2007-2011 reported at a district level (n = 75 were examined in relation to landscape risk factors. Landscape pattern indices were used to quantify landscape patterns associated with JE risk. The relative spatial distribution of landscape risk factors were compared using geographically weighted regression. Pattern indices describing the amount of irrigated land edge density and the degree of landscape mixing for irrigated areas were positively associated with JE and AES, while fragmented forest measured by the number of forest patches were negatively associated with AES and JE. For both JE and AES, the local GWR models outperformed global models, indicating spatial heterogeneity in risks. Temporally, the patterns of JE and AES risk were almost identical; suggesting the relative higher caseload of AES compared to JE could provide a valuable early-warning signal for JE surveillance and reduce diagnostic testing costs. Overall, the landscape variables associated with a high degree of landscape mixing and small scale irrigated agriculture were positively linked to JE and AES risk, highlighting the importance of integrating land management policies, disease prevention strategies and promoting healthy sustainable livelihoods

  5. Differential Diagnosis of Japanese Encephalitis Virus Infections with the Inbios JE Detect™ and DEN Detect™ MAC-ELISA Kits

    Science.gov (United States)

    Johnson, Barbara W.; Goodman, Christin H.; Jee, Youngmee; Featherstone, David A.

    2016-01-01

    Japanese encephalitis virus (JEV) is the leading cause of pediatric viral neurological disease in Asia. The JEV-specific IgM antibody-capture enzyme-linked immunosorbent assay (MAC-ELISA) in cerebrospinal fluid (CSF) and serum is the recommended method of laboratory diagnosis, but specificity of JEV MAC-ELISA can be low due to cross-reactivity. To increase the specificity of the commercially available JE Detect™ MAC-ELISA (JE Detect), a differential testing algorithm was developed in which samples tested by JE Detect with positive results were subsequently tested by the DEN Detect™ MAC-ELISA (DEN Detect) kit, and results of both tests were used to make the final interpretation. The testing algorithm was evaluated with a reference panel of serum and CSF samples submitted for confirmatory testing. In serum, the false Japanese encephalitis (JE) positive rate was reduced, but sequential testing in CSF resulted in reduced JE specificity, as true JEV+ CSF samples had positive results by both JE Detect and DEN Detect and were classified as JE− (dengue virus [DENV]+). Differential diagnosis of JE by sequential testing with JE Detect and DEN Detect increased specificity for JE in serum, but more data with CSF is needed to make a final determination on the usefulness of this testing algorithm for CSF. PMID:26856911

  6. Differential Diagnosis of Japanese Encephalitis Virus Infections with the Inbios JE Detect™ and DEN Detect™ MAC-ELISA Kits.

    Science.gov (United States)

    Johnson, Barbara W; Goodman, Christin H; Jee, Youngmee; Featherstone, David A

    2016-04-01

    Japanese encephalitis virus (JEV) is the leading cause of pediatric viral neurological disease in Asia. The JEV-specific IgM antibody-capture enzyme-linked immunosorbent assay (MAC-ELISA) in cerebrospinal fluid (CSF) and serum is the recommended method of laboratory diagnosis, but specificity of JEV MAC-ELISA can be low due to cross-reactivity. To increase the specificity of the commercially available JEDetect™ MAC-ELISA (JEDetect), a differential testing algorithm was developed in which samples tested by JEDetect with positive results were subsequently tested by the DENDetect™ MAC-ELISA (DENDetect) kit, and results of both tests were used to make the final interpretation. The testing algorithm was evaluated with a reference panel of serum and CSF samples submitted for confirmatory testing. In serum, the false Japanese encephalitis (JE) positive rate was reduced, but sequential testing in CSF resulted in reduced JE specificity, as true JEV+ CSF samples had positive results by both JEDetect and DENDetect and were classified as JE- (dengue virus [DENV]+). Differential diagnosis of JE by sequential testing with JEDetect and DENDetect increased specificity for JE in serum, but more data with CSF is needed to make a final determination on the usefulness of this testing algorithm for CSF.

  7. DC-SIGN Increases Japanese Encephalitis Virus Infection

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

    2013-11-01

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

  8. Antioxidants: potential antiviral agents for Japanese encephalitis virus infection.

    Science.gov (United States)

    Zhang, Yu; Wang, Zehua; Chen, Huan; Chen, Zongtao; Tian, Yanping

    2014-07-01

    Japanese encephalitis (JE) is prevalent throughout eastern and southern Asia and the Pacific Rim. It is caused by the JE virus (JEV), which belongs to the family Flaviviridae. Despite the importance of JE, little is known about its pathogenesis. The role of oxidative stress in the pathogenesis of viral infections has led to increased interest in its role in JEV infections. This review focuses mainly on the role of oxidative stress in the pathogenesis of JEV infection and the antiviral effect of antioxidant agents in inhibiting JEV production. First, this review summarizes the pathogenesis of JE. The pathological changes include neuronal death, astrocyte activation, and microglial proliferation. Second, the relationship between oxidative stress and JEV infection is explored. JEV infection induces the generation of oxidants and exhausts the supply of antioxidants, which activates specific signaling pathways. Finally, the therapeutic efficacy of a variety of antioxidants as antiviral agents, including minocycline, arctigenin, fenofibrate, and curcumin, was studied. In conclusion, antioxidants are likely to be developed into antiviral agents for the treatment of JE. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Post-marketing surveillance of live-attenuated Japanese encephalitis vaccine safety in China.

    Science.gov (United States)

    Wang, Yali; Dong, Duo; Cheng, Gang; Zuo, Shuyan; Liu, Dawei; Du, Xiaoxi

    2014-10-07

    Japanese encephalitis (JE) is the most severe form of viral encephalitis in Asia and no specific treatment is available. Vaccination provides an effective intervention to prevent JE. In this paper, surveillance data for adverse events following immunization (AEFI) related to SA-14-14-2 live-attenuated Japanese encephalitis vaccine (Chengdu Institute of Biological Products) was presented. This information has been routinely generated by the Chinese national surveillance system for the period 2009-2012. There were 6024 AEFI cases (estimated reported rate 96.55 per million doses). Most common symptoms of adverse events were fever, redness, induration and skin rash. There were 70 serious AEFI cases (1.12 per million doses), including 9 cases of meningoencephalitis and 4 cases of death. The post-marketing surveillance data add the evidence that the Chengdu institute live attenutated vaccine has a reasonable safety profile. The relationship between encephalitis and SA-14-14-2 vaccination should be further studied.

  10. 日本脑炎流行病学和疫苗研制%Japanese Encephalitis Epidemiology and Vaccine Production

    Institute of Scientific and Technical Information of China (English)

    Akira Oya

    2002-01-01

    @@ Japanese encephalitis (JE) caused by Japanese encephalitis virus (JEV) is widely spread in the east and southeast part of Asia and number of human cases are estimated approximately 20000 annually in the world. The epidemic area is expanding recently as a newly emerging disease in the Oceanic countries.

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

    Science.gov (United States)

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

  12. Dengue-associated hemophagocytic syndrome in a Japanese traveler: a case report.

    Science.gov (United States)

    Kobayashi, Ken-ichiro; Hikone, Mayu; Sakamoto, Naoya; Iwabuchi, Sentaro; Kashiura, Masahiro; Takasaki, Tomohiko; Fujita, Hiroshi; Ohnishi, Kenji

    2015-01-01

    Hemophagocytic syndrome (HPS) can develop as a complication of dengue in rare cases, but its relationship with dengue is not well known. We report a case of dengue-associated HPS with liver involvement and coagulopathy. The patient, a Japanese female traveler who had recently returned from Thailand, had severe complications of dengue infection, but she recovered fully with symptomatic treatment. © 2014 International Society of Travel Medicine.

  13. Spatiotemporal patterns of Japanese encephalitis in China, 2002-2010.

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    Li-Ya Wang

    Full Text Available OBJECTIVE: The aim of the study is to examine the spatiotemporal pattern of Japanese Encephalitis (JE in mainland China during 2002-2010. Specific objectives of the study were to quantify the temporal variation in incidence of JE cases, to determine if clustering of JE cases exists, to detect high risk spatiotemporal clusters of JE cases and to provide evidence-based preventive suggestions to relevant stakeholders. METHODS: Monthly JE cases at the county level in mainland China during 2002-2010 were obtained from the China Information System for Diseases Control and Prevention (CISDCP. For the purpose of the analysis, JE case counts for nine years were aggregated into four temporal periods (2002; 2003-2005; 2006; and 2007-2010. Local Indicators of Spatial Association and spatial scan statistics were performed to detect and evaluate local high risk space-time clusters. RESULTS: JE incidence showed a decreasing trend from 2002 to 2005 but peaked in 2006, then fluctuated over the study period. Spatial cluster analysis detected high value clusters, mainly located in Southwestern China. Similarly, we identified a primary spatiotemporal cluster of JE in Southwestern China between July and August, with the geographical range of JE transmission increasing over the past years. CONCLUSION: JE in China is geographically clustered and its spatial extent dynamically changed during the last nine years in mainland China. This indicates that risk factors for JE infection are likely to be spatially heterogeneous. The results may assist national and local health authorities in the development/refinement of a better preventive strategy and increase the effectiveness of public health interventions against JE transmission.

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

    Science.gov (United States)

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

    2016-04-01

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

  15. Incidence of dengue virus infection among Japanese travellers, 2006 to 2010

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    Yuki Tada

    2012-06-01

    Full Text Available Introduction: Dengue continues to be a global public health concern. In Japan, although dengue cases are currently seen only among travellers returning from endemic areas, the number of reported cases is rising according to the national case-based surveillance system. We evaluated the characteristics of dengue cases imported into Japan and the relationship between the incidence of infection and season of travel to popular destinations.Methods: Dengue cases reported to the national surveillance system were retrospectively examined. The number of reported cases per number of Japanese travellers to a dengue-endemic country was calculated to estimate the country-specific incidence of imported dengue virus infection. The incidence of dengue infection among Japanese travellers was compared between dengue high season and low season in each country using relative risk (RR and associated 95% confidence intervals (CI.Results: Among 540 Japanese residents who were reported as dengue cases from 2006 to 2010, the majority had travelled to Indonesia, India, the Philippines and Thailand. The RR of dengue infection among Japanese travellers during dengue high season versus low season was 4.92 (95% CI: 3.01–8.04 for the Philippines, 2.76 (95% CI: 1.67–4.54 for Thailand and 0.37 (95% CI: 0.15–0.92 for Indonesia.Discussion: Overall, higher incidence of imported cases appeared to be related to historic dengue high seasons. Travellers planning to visit dengue-endemic countries should be aware of historic dengue seasonality and the current dengue situation.

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

    Science.gov (United States)

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

    2016-05-01

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

  17. A Spatial and Temporal Analysis of Japanese Encephalitis in Mainland China, 1963–1975: A Period without Japanese Encephalitis Vaccination

    Science.gov (United States)

    Ren, Zhoupeng; Cao, Yuxi; Wang, Jinfeng; Liang, Guodong

    2014-01-01

    More than a million Japanese encephalitis (JE) cases occurred in mainland China from the 1960s to 1970s without vaccine interventions. The aim of this study is to analyze the spatial and temporal pattern of JE cases reported in mainland China from 1965 to 1973 in the absence of JE vaccination, and to discuss the impacts of climatic and geographical factors on JE during that period. Thus, the data of reported JE cases at provincial level and monthly precipitation and monthly mean temperature from 1963 to 1975 in mainland China were collected. Local Indicators of Spatial Association analysis was performed to identify spatial clusters at the province level. During that period, The epidemic peaked in 1966 and 1971 and the JE incidence reached up to 20.58/100000 and 20.92/100000, respectively. The endemic regions can be divided into three classes including high, medium, and low prevalence regions. Through spatial cluster analysis, JE epidemic hot spots were identified; most were located in the Yangtze River Plain which lies in the southeast of China. In addition, JE incidence was shown to vary among eight geomorphic units in China. Also, the JE incidence in the Loess Plateau and the North China Plain was showed to increase with the rise of temperature. Likewise, JE incidence in the Loess Plateau and the Yangtze River Plain was observed a same trend with the increase of rainfall. In conclusion, the JE cases clustered geographically during the epidemic period. Besides, the JE incidence was markedly higher on the plains than plateaus. These results may provide an insight into the epidemiological characteristics of JE in the absence of vaccine interventions and assist health authorities, both in China and potentially in Europe and Americas, in JE prevention and control strategies. PMID:24911168

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

    Directory of Open Access Journals (Sweden)

    Rong-Hong Hua

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

  19. Encephalitis

    Science.gov (United States)

    ... with anyone who has encephalitis. Controlling mosquitoes (a mosquito bite can transmit some viruses) may reduce the chance of some infections that can lead to encephalitis. Apply an insect repellant containing the chemical, DEET when you go outside ( ...

  20. Japanese encephalitis virus infection decrease endogenous IL-10 production: correlation with microglial activation and neuronal death.

    Science.gov (United States)

    Swarup, Vivek; Ghosh, Joydeep; Duseja, Rachna; Ghosh, Soumya; Basu, Anirban

    2007-06-13

    The anti-inflammatory cytokine interleukin (IL)-10 is synthesized in the central nervous system (CNS) and acts to limit clinical symptoms of stroke, multiple sclerosis, Alzheimer's disease, meningitis, and the behavioral changes that occur during bacterial infections. Expression of IL-10 is critical during the course of most major diseases in the CNS and promotes survival of neurons and all glial cells in the brain by blocking the effects of proinflammatory cytokines and by promoting expression of cell survival signals. In order to assess functional importance of this cytokine in viral encephalitis we have exploited an experimental model of Japanese encephalitis (JE). We report for the first time that in Japanese encephalitis, there is a progressive decline in level of IL-10. The extent of progressive decrease in IL-10 level following viral infection is inversely proportional to the increase in the level of proinflammatory cytokines as well as negative consequences that follows viral infection.

  1. A large outbreak of Japanese encephalitis predominantly among adults in northern region of West Bengal, India.

    Science.gov (United States)

    Gurav, Yogesh K; Bondre, Vijay P; Tandale, Babasaheb V; Damle, Rekha G; Mallick, Sanjay; Ghosh, Uday S; Nag, Shankha S

    2016-11-01

    Unusual rise of acute encephalitis syndrome cases (AES) were reported in July 2014 in the northern region of West Bengal, India. Investigations were carried out to characterize the outbreak and to identify the associated virus etiology. This observational study is based on 398 line listed AES cases, mostly (70.8%, 282/398) adults, with case fatality ratio of 28.9% (115/398). Japanese encephalitis virus infection was detected in 134 (49.4%) among 271 AES cases tested and most of them (79.1%, 106/134) were adults. The study reports a large outbreak of genotype III Japanese encephalitis among adults in northern region of West Bengal, India. J. Med. Virol. 88:2004-2011, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  2. Is a booster dose necessary in children after immunization with live attenuated Japanese encephalitis vaccine?

    Science.gov (United States)

    Choi, Ui Yoon; Lee, Soo Young; Kim, Ki Hwan; Kim, Dong Soo; Choi, Kyong Min; Cha, Sung Ho; Kang, Jin Han

    2013-10-01

    Japanese encephalitis virus is a common cause of encephalitis in Asian children; therefore, maintenance of immunity against Japanese encephalitis virus is essential. Although many countries recommend booster vaccination, some trials have concluded that administration of one or two vaccinations is sufficient. The current study was conducted to evaluate immunogenicity and safety after a booster vaccination with live attenuated vaccine. For 68 study subjects, measurement of antibody titer was performed before and at 4-6 weeks after administration of a booster dose. Adverse reactions occurring at the injection site and systemic adverse reactions were documented. The percentages of subjects with seroprotective neutralizing antibody titers was 100% before and after booster vaccination, and the geometric mean titer increased after booster vaccination. Thus, we predict that immunity will be maintained for a long time by an amnestic response. Low percentages of adverse reactions indicated the safety of the immunizations.

  3. Susceptibility of a North American Culex quinquefasciatus to Japanese encephalitis virus

    Science.gov (United States)

    Japanese encephalitis virus (JEV) is a flavivirus that is transmitted by Culex (Cx.) tritaeniorhynchus in tropical and subtropical regions of Asia. The endemic transmission cycle involves domestic pigs and avian species that serve as amplification hosts; humans are incidental hosts that cannot devel...

  4. Japanese encephalitis in a Danish short-term traveler to Cambodia

    DEFF Research Database (Denmark)

    Werlinrud, Anne M; Christiansen, Claus B; Koch, Anders

    2011-01-01

    We present a recent case of Japanese encephalitis in a Danish male traveler to Cambodia, who we believe is the second Danish case within the last 15 years. Although both this and a number of other travel-related cases occurred in short-term travelers, change in vaccination recommendations...

  5. Multiplex PCR for the Detection of 10 Viruses Causing Encephalitis/Encephalopathy and its Application to Clinical Samples Collected from Japanese Children with Suspected Viral.

    Science.gov (United States)

    Pham, Ngan T K; Ushijima, Hiroshi; Thongprachum, Aksara; Trinh, Quang D; Khamrin, Pattara; Arakawa, Chikako; Ishii, Wakako; Okitsu, Shoko; Komine-Aizawa, Shihoko; Hayakawa, Satoshi

    2017-01-01

    Acute encephalitis is a serious neurological condition having a high mortality rate and affecting both children and adults. This study aimed to develop a multiplex PCR method for the simultaneous screening of clinical samples for the presence of the 10 viruses presently considered as the major viral causes of acute encephalitis/ encephalopathy in Asia. Using previously published primers that have been widely used to screen for herpes virus-6, influenza A virus, human parechovirus, herpes simplex viruses 1 and 2, Japanese encephalitis virus, group A rotavirus, enterovirus, adenovirus, and dengue virus in clinical samples, a single-tube multiplex PCR assay was developed and was tested for its sensitivity and specificity. The method was then applied to screen 57 clinical samples, consisting of 13 fecal samples, 5 throat swabs, 3 post-nasal swabs, 18 serum samples, and 18 cerebrospinal fluid (CSF) samples, collected from 18 hospitalized Japanese children with suspected viral encephalitis/encephalopathy for the target viruses, and the results were compared with those of a monoplex PCR method. Positive viral controls of the 10 viruses were correctly typed using this multiplex PCR method. The multiplex PCR method showed high specificity with no unspecific amplification to non-target viruses. The results of applying this PCR method for screening clinical samples showed that 6 fecal samples, 2 serum samples, and 1 CSF sample collected from 7 patients were positive for a virus, specifically group A rotavirus (4 patients, 22.2%), enterovirus (2 patients, 11.1%), or adenovirus (1 patient, 5.6%). In comparison with monoplex PCR, for group A rotavirus, enterovirus, and adenovirus, the sensitivity of this multiplex PCR method decreased for serum, cerebrospinal fluid, and throat swab samples. This newly developed multiplex PCR method is a simple, rapid diagnostic tool and can be used to screen clinical samples for viruses causing acute encephalitis/encephalopathy in children in

  6. Genotype-specific neutralization determinants in envelope protein: implications for the improvement of Japanese encephalitis vaccine.

    Science.gov (United States)

    Ye, Qing; Xu, Yan-Peng; Zhang, Yu; Li, Xiao-Feng; Wang, Hong-Jiang; Liu, Zhong-Yu; Li, Shi-Hua; Liu, Long; Zhao, Hui; Nian, Qing-Gong; Deng, Yong-Qiang; Qin, E-De; Qin, Cheng-Feng

    2015-08-01

    Japanese encephalitis remains the leading cause of viral encephalitis in children in Asia and is expanding its geographical range to larger areas in Asia and Australasia. Five genotypes of Japanese encephalitis virus (JEV) co-circulate in the geographically affected areas. In particular, the emergence of genotype I (GI) JEV has displaced genotype III (GIII) as the dominant circulating genotype in many Asian regions. However, all approved vaccine products are derived from GIII strains. In the present study, bioinformatic analysis revealed that GI and GIII JEV strains shared two distinct amino acid residues within the envelope (E) protein (E222 and E327). By using reverse genetics approaches, A222S and S327T mutations were demonstrated to decrease live-attenuated vaccine (LAV) SA14-14-2-induced neutralizing antibodies in humans, without altering viral replication. A222S or S327T mutations were then rationally engineered into the infectious clone of SA14-14-2, and the resulting mutant strains retained the same genetic stability and attenuation characteristics as the parent strain. More importantly, immunization of mice with LAV-A222S or LAV-S327T elicited increased neutralizing antibodies against GI strains. Together, these results demonstrated that E222 and E327 are potential genotype-related neutralization determinants and are critical in determining the protective efficacy of live Japanese encephalitis vaccine SA14-14-2 against circulating GI strains. Our findings will aid in the rational design of the next generation of Japanese encephalitis LAVs capable of providing broad protection against all JEV strains belonging to different genotypes.

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

    Science.gov (United States)

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

  8. Endemic Venezuelan equine encephalitis in the Americas: hidden under the dengue umbrella

    Science.gov (United States)

    Aguilar, Patricia V; Estrada-Franco, Jose G; Navarro-Lopez, Roberto; Ferro, Cristina; Haddow, Andrew D; Weaver, Scott C

    2011-01-01

    Venezuelan equine encephalitis (VEE) is an emerging infectious disease in Latin America. Outbreaks have been recorded for decades in countries with enzootic circulation, and the recent implementation of surveillance systems has allowed the detection of additional human cases in countries and areas with previously unknown VEE activity. Clinically, VEE is indistinguishable from dengue and other arboviral diseases and confirmatory diagnosis requires the use of specialized laboratory tests that are difficult to afford in resource-limited regions. Thus, the disease burden of endemic VEE in developing countries remains largely unknown, but recent surveillance suggests that it may represent up to 10% of the dengue burden in neotropical cities, or tens-of-thousands of cases per year throughout Latin America. The potential emergence of epizootic viruses from enzootic progenitors further highlights the need to strengthen surveillance activities, identify mosquito vectors and reservoirs and develop effective strategies to control the disease. In this article, we provide an overview of the current status of endemic VEE that results from spillover of the enzootic cycles, and we discuss public health measures for disease control as well as future avenues for VEE research. PMID:21765860

  9. RIG-I knockdown impedes neurogenesis in a murine model of Japanese encephalitis.

    Science.gov (United States)

    Mukherjee, Sriparna; Ghosh, Sourish; Nazmi, Arshed; Basu, Anirban

    2015-02-01

    Retinoic acid inducible gene I (RIG-I) is a well established pattern recognition receptor (PRR) in neurons infected with Japanese encephalitis virus (JEV) as reported previously from our laboratory. Japanese encephalitis (JE) virus infection in brain has been shown to decrease the proliferation of neural stem/progenitor cells (NSPCs) which has its implications in neurological sequelae in JE survivors. We have found that ablation of RIG-I both in vivo and in vitro models results in significant decrease in NSPC proliferation post JEV infection. We hypothesize that knockdown of RIG-I diminishes the expression of antiviral molecules resulting in an increase in viral replication, which in turn results in enhancement of the expression of cell cycle inhibitors, hence affecting the proliferation of NSPCs. © 2014 International Federation for Cell Biology.

  10. Immunogenicity of One Dose of Vero Cell Culture-Derived Japanese Encephalitis (JE) Vaccine in Adults Previously Vaccinated with Mouse Brain-Derived JE Vaccine

    Science.gov (United States)

    2012-03-06

    Naval Health Research Center Immunogenicity of One Dose of Vero Cell Culture-derived Japanese Encephalitis (JE) Vaccine in Adults Previously...www.elsev ier .com/ locate /vacc ine mmunogenicity of one dose of Vero cell culture-derived Japanese encephalitis JE) vaccine in adults...derived Japanese encephalitis (JE) vaccine (JE-VC) as a booster among individuals who previously received inactivated mouse brain-derived

  11. The cellular immune response plays an important role in protecting against dengue virus in the mouse encephalitis model.

    Science.gov (United States)

    Gil, Lázaro; López, Carlos; Blanco, Aracelys; Lazo, Laura; Martín, Jorge; Valdés, Iris; Romero, Yaremis; Figueroa, Yassel; Guillén, Gerardo; Hermida, Lisset

    2009-02-01

    For several years, researchers have known that the generation of neutralizing antibodies is a prerequisite for attaining adequate protection against dengue virus. Nevertheless, the cellular immune response is the principal arm of the adaptive immune system against non-cytopathic viruses such as dengue, as once the virus enters into the cell it is necessary to destroy it to eliminate the virus. To define the role of the cellular immune response in the protection against dengue, we selected the mouse encephalitis model. Mice were immunized with a single dose of infective dengue 2 virus and different markers of both branches of the induced adaptive immunity were measured. Animals elicited a broad antibody response against the four dengue virus serotypes, but neutralizing activity was only detected against the homologous serotype. On the other hand, the splenocytes of the infected animals strongly proliferated after in vitro stimulation with the homologous virus, and specifically the CD8 T-cell subset was responsible for the secretion of the cytokine IFN-gamma. Finally, to define the role of T cells in in vivo protection, groups of animals were inoculated with the depleting monoclonal antibodies anti-CD4 or anti-CD8. Only depletion with anti-CD8 decreased to 50% the level of protection reached in the non-depleted mice. The present work constitutes the first report defining the role of the cellular immune response in protection against dengue virus in the mouse model.

  12. Acute Transverse Myelitis (Ascending Myelitis as the Initial Manifestation of Japanese Encephalitis: A Rare Presentation

    Directory of Open Access Journals (Sweden)

    Varshney Ankur Nandan

    2013-01-01

    Full Text Available Japanese encephalitis, an inflammatory brain disease prevalent in Southeast Asia, usually presented with fever, headache, convulsions, brain stem signs with pyramidal and extrapyramidal features, and altered sensorium. Acute transverse myelitis, as the initial manifestation of Japanese encephalitis, is an unusual manifestation and is seldom reported. We hereby report a case of 13-year-old adolescent boy who presented to us with fever and acute onset paraparesis with urinary retention initially, progressing to quadriparesis and then followed by headache and altered sensorium. Brain MRI revealed bilateral basal ganglia that were grossly swollen with vasogenic edema tracking along internal capsule and midbrain. Adjacent ventrolateral thalamus and internal capsule also showed mild abnormal intensities. Spinal screening showed abnormal cord intensities in entire cord with gross edema in cervical and conus regions. He had elevated IgM titres against JE virus in cerebrospinal fluid. The patient was treated conservatively along with intravenous methyl prednisolone for 5 days. He regained near normal power at 3 months in followup, but hesitancy, dysarthria, and slowness of movement still persisted. To conclude, a young boy presenting with ATM in an endemic region of JE, then a possibility of Japanese encephalitis, should be sought by clinicians as early use of immunomodulator shows survival benefit.

  13. Immunogenicity and safety of currently available Japanese encephalitis vaccines: A systematic review

    Science.gov (United States)

    Li, Xing; Ma, Shu-Juan; Liu, Xie; Jiang, Li-Na; Zhou, Jun-Hua; Xiong, Yi-Quan; Ding, Hong; Chen, Qing

    2015-01-01

    A number of Japanese encephalitis (JE) vaccines have been used for preventing Japanese encephalitis around the world. We here reviewed the immunogenicity and safety of the currently available Japanese encephalitis vaccines. We searched Pubmed, Embase, Web of Science, the Cochrane Library and other online databases up to March 25, 2014 for studies focusing on currently used JE vaccines in any language. The primary outcomes were the seroconversion rate against JEV and adverse events. Meta-analysis was performed for the primary outcome when available. A total of 51 articles were included. Studies were grouped on the basic types of vaccines. This systematic review led to 2 aspects of the conclusions. On one hand, all the currently available JE vaccines are safe and effective. On the other hand, the overall of JE vaccine evaluation is disorganized, the large variation in study designs, vaccine types, schedules, doses, population and few hand-to-hand trails, make direct comparisons difficult. In order to make a more evidence-based decision on optimizing the JE vaccine, it is warranted to standardize the JE vaccine evaluation research. PMID:25668666

  14. Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): Japanese encephalitis (JE)

    DEFF Research Database (Denmark)

    EFSA Panel on Animal Health and Welfare; More, Simon J.; Bøtner, Anette

    2017-01-01

    Japanese encephalitis (JE) has been assessed according to the criteria of the Animal Health Law (AHL), in particular criteria of Article 7 on disease profile and impacts, Article 5 on the eligibility of Japanese encephalitis to be listed, Article 9 for the categorisation of Japanese encephalitis...... according to disease prevention and control rules as in Annex IV and Article 8 on the list of animal species related to Japanese encephalitis. The assessment has been performed following a methodology composed of information collection and compilation, expert judgement on each criterion at individual and...

  15. Prevalence of antibodies to Japanese encephalitis virus among inhabitants in Java Island, Indonesia, with a small pig population.

    Science.gov (United States)

    Konishi, Eiji; Sakai, Yohei; Kitai, Yoko; Yamanaka, Atsushi

    2009-05-01

    Japanese encephalitis virus (JEV) is maintained through a transmission cycle between amplifier swine and vector mosquitoes in a peridomestic environment. Thus, studies on natural JEV activities in an environment with a small size of pig population have been limited. Here, we surveyed antibodies against JEV in inhabitants of Jakarta and Surabaya located in Java Island (Indonesia), which has a small swine population. Overall, 2.2% of 1,211 sera collected in Jakarta and 1.8% of 1,751 sera collected in Surabaya had neutralizing antibody titers of >or= 1:160 (90% plaque reduction). All the samples with titers of >or= 1:160 against JEV were also examined for neutralizing antibodies against each of four dengue viruses to confirm that JEV antibody prevalences obtained in the present survey were not attributable to serologic cross-reactivities among flaviviruses distributed in Java. These results indicated that people in Java Island are exposed to natural JEV infections despite a small swine population.

  16. Identification of linear human B-cell epitopes of tick-borne encephalitis virus

    OpenAIRE

    Kuivanen, Suvi; Hepojoki, Jussi; Vene, Sirkka; Vaheri, Antti; Vapalahti, Olli

    2014-01-01

    Background Tick-borne encephalitis (TBE) is a central nervous system infection transmitted to humans by ticks. The causative agent, tick-borne encephalitis virus (TBEV), belongs to the genus Flavivirus (family Flaviviridae), which includes globally important arthropod-borne viruses, such as dengue, Yellow fever, Japanese encephalitis and West Nile viruses. Flaviviruses are highly cross-reactive in serological tests that are currently based on viral envelope proteins. The envelope (E) protein ...

  17. Encephalitis

    Science.gov (United States)

    ... to be common, such as measles, mumps, and German measles. But because many countries immunize against them, ... problems like seizures, difficulties with muscle coordination, and learning disabilities. Can I Prevent Encephalitis? The best way ...

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

    Science.gov (United States)

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

    2013-01-01

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

  19. Etanercept reduces neuroinflammation and lethality in mouse model of Japanese encephalitis.

    Science.gov (United States)

    Ye, Jing; Jiang, Rong; Cui, Min; Zhu, Bibo; Sun, Leqiang; Wang, Yueyun; Zohaib, Ali; Dong, Qian; Ruan, Xindi; Song, Yunfeng; He, Wen; Chen, Huanchun; Cao, Shengbo

    2014-09-15

    Japanese encephalitis virus (JEV) is a neurotropic flavivirus that causes Japanese encephalitis (JE), which leads to high fatality rates in human. Tumor necrosis factor alpha (TNF-α) is a key factor that mediates immunopathology in the central nervous system (CNS) during JE. Etanercept is a safe anti-TNF-α drug that has been commonly used in the treatment of various human autoimmune diseases. The effect of etanercept on JE was investigated with a JEV-infected mouse model. Four groups of mice were assigned to receive injections of phosphate-buffered saline, etanercept, JEV, or JEV plus etanercept. Inflammatory responses in mouse brains and mortality of mice were evaluated within 23 days post infection. The in vitro assay with mouse neuron/glia cultures showed that etanercept treatment reduced the inflammatory response induced by JEV infection. In vivo experiments further demonstrated that administration of etanercept protected mice from JEV-induced lethality. Neuronal damage, glial activation, and secretion of proinflammatory cytokines were found to be markedly decreased in JEV-infected mice that received etanercept treatment. Additionally, etanercept treatment restored the integrity of the blood-brain barrier and reduced viral load in mouse brains. Etanercept effectively reduces the inflammation and provides protection against acute encephalitis in a JEV-infected mouse model. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. Increasing trend of Japanese encephalitis cases in West Bengal, India - a threat to paediatric population

    Directory of Open Access Journals (Sweden)

    Debjani Taraphdar

    2012-10-01

    Full Text Available Objective: To detect the Japanese encephalitis virus (JEV as the etiologic agent from the acute encephalitis syndrome (AES cases mainly amongst the children and young adults from vaccinated and non-vaccinated districts of West Bengal. Methods: For the detection of JEV, a total of 828 sera were referred from vaccinated and non vaccinated districts of West Bengal during 2005-2011. Japanese encephalitis (JE positive cases were confirmed by ELISA and RT-PCR method. Results: Out of 828 cases, 245 samples were positive by ELISA method and 46 samples were positive by RT-PCR method. Out of 291 total positive cases, 162 (55.6% were below 20 years of age. Initially in 2005, JE cases were highest amongst the children and young adults (0-20 years. After vaccination, although the JE cases declined gradually in the vaccinated districts, but again from 2010, JE cases from the said age group showed an increasing trend from those districts. JE cases were also reported from other endemic zones of this state, which were still non-vaccinated. Conclusions: In West Bengal, JE cases are still predominated among children and young adults till the year 2011. Mass scale vaccination programme and investigation on the circulating strains are essentially required to find out the reasons of increasing tendency of JE cases in this state.

  1. Evaluation of antiviral activity of essential oil of Trachyspermum Ammi against Japanese encephalitis virus

    Directory of Open Access Journals (Sweden)

    Soumen Roy

    2015-01-01

    Full Text Available Background: Japanese encephalitis is a leading form of viral encephalitis, prevalent mostly in South Eastern Asia caused by Japanese encephalitis virus (JEV. It is transmitted by the mosquitoes of the Culex sp. The disease affects children and results in 50% result in permanent neuropsychiatric disorder. There arises a need to develop a safe, affordable, and potent anti-viral agent against JEV. This study aimed to assess the antiviral activity of ajwain (Trachyspermum ammi: Umbellifereae essential oil against JEV. Materials and Methods: Ajwain oil was extracted by distillation method and in vitro cytotoxicity assay was performed in vero cell line by 3-(4, 5-dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide (MTT assay method. JEV titer was determined by plaque assay and in vitro antiviral activity of ajwain oil was quantified by the plaque reduction neutralization test (PRNT. Results: Cytotoxic concentration of the oil was found to be 1 mg/ml by MTT assay. The titer of the virus pool was found to be 50× 10 7 PFU/ml. we observed 80% and 40% virus inhibition in 0.5mg/ml of ajwain oil by PRNT method in preexposure treatment and postexposure treatment (antiviral activity, respectively. Conclusion: Our data indicate ajwain oil has potential in vitro antiviral activity against JEV. Further, the active biomolecule will be purified and evaluated for anti-JEV activity and also to scale up for in vivo trial to evaluate the efficacy of ajwain oil in future.

  2. Dengue Sentinel Traveler Surveillance: Monthly and Yearly Notification Trends among Japanese Travelers, 2006-2014.

    Directory of Open Access Journals (Sweden)

    Munehisa Fukusumi

    2016-08-01

    Full Text Available Dengue is becoming an increasing threat to non-endemic countries. In Japan, the reported number of imported cases has been rising, and the first domestic dengue outbreak in nearly 70 years was confirmed in 2014, highlighting the need for greater situational awareness and better-informed risk assessment.Using national disease surveillance data and publically available traveler statistics, we compared monthly and yearly trends in the destination country-specific dengue notification rate per 100,000 Japanese travelers with those of domestic dengue cases in the respective country visited during 2006-2014. Comparisons were made for countries accounting for the majority of importations; yearly comparisons were restricted to countries where respective national surveillance data were publicly available.There were 1007 imported Japanese dengue cases (Bali, Indonesia (n = 202, the Philippines (n = 230, Thailand (n = 160, and India (n = 152. Consistent with historic local dengue seasonality, monthly notification rate among travelers peaked in August in Thailand, September in the Philippines, and in Bali during April with a smaller peak in August. While the number of travelers to Bali was greatest in August, the notification rate was highest in April. Annually, trends in the notification rate among travelers to the Philippines and Thailand also closely reflected local notification trends.Travelers to dengue-endemic countries appear to serve as reliable "sentinels", with the trends in estimated risk of dengue infection among Japanese travelers closely reflecting local dengue trends, both seasonally and annually. Sentinel traveler surveillance can contribute to evidence-based pretravel advice, and help inform risk assessments and decision-making for importation and potentially for subsequent secondary transmission. As our approach takes advantage of traveler data that are readily available as a proxy denominator, sentinel traveler surveillance can be a

  3. A tropical menace of co-infection of Japanese encephalitis and neurocysticercosis in two children

    Directory of Open Access Journals (Sweden)

    Sangeetha Yoganathan

    2016-01-01

    Full Text Available Japanese encephalitis (JE is a mosquito borne encephalitis caused by Flavivirus. Neurocysticercosis (NCC is a parasitic disease of the central nervous system caused by Taenia solium. In this report, we describe the clinical profile, imaging findings, and outcome of two children with JE and coexisting NCC. Eleven and thirteen-year-old boys from the same town of Jharkhand state were brought with history of fever, seizures, altered sensorium, and extrapyramidal symptoms. Dystonia, hypomimia, bradykinesia, and dyskinesia were observed. Meige syndrome observed in one of the children is a novel finding. Magnetic resonance imaging of the brain revealed findings suggestive of JE with cysticercal granulomas. There are few reports of coexistence of JE and NCC in children. Both children were treated with ribavirin, and follow-up imaging had shown significant resolution of signal changes. Both the children had shown marked clinical improvement. Ribavirin was found to beneficial in reducing the morbidity in our patients.

  4. A tropical menace of co-infection of Japanese encephalitis and neurocysticercosis in two children

    Science.gov (United States)

    Yoganathan, Sangeetha; Sudhakar, Sniya Valsa; Thomas, Maya Mary; Yadav, Vikas Kapildeo

    2016-01-01

    Japanese encephalitis (JE) is a mosquito borne encephalitis caused by Flavivirus. Neurocysticercosis (NCC) is a parasitic disease of the central nervous system caused by Taenia solium. In this report, we describe the clinical profile, imaging findings, and outcome of two children with JE and coexisting NCC. Eleven and thirteen-year-old boys from the same town of Jharkhand state were brought with history of fever, seizures, altered sensorium, and extrapyramidal symptoms. Dystonia, hypomimia, bradykinesia, and dyskinesia were observed. Meige syndrome observed in one of the children is a novel finding. Magnetic resonance imaging of the brain revealed findings suggestive of JE with cysticercal granulomas. There are few reports of coexistence of JE and NCC in children. Both children were treated with ribavirin, and follow-up imaging had shown significant resolution of signal changes. Both the children had shown marked clinical improvement. Ribavirin was found to beneficial in reducing the morbidity in our patients. PMID:27606026

  5. Entomological and serological investigation of Japanese encephalitis in endemic area of eastern Uttar Pradesh, India.

    Science.gov (United States)

    Nyari, Nikky; Singh, Dharamveer; Kakkar, Kavita; Sharma, Swati; Pandey, S N; Dhole, T N

    2015-12-01

    Japanese encephalitis virus (JEV), a mosquito borne pathogen, is one of the major causes of viral encephalitis in eastern Uttar Pradesh, India. The objective of this work was to evaluate the entomological based virological surveillance of Japanese encephalitis (JE) in the highly endemic area of eastern Uttar Pradesh. The study was carried out during September 2010 to March 2013 in Gorakhpur district of Uttar Pradesh. A total of 251 adult mosquito pools and 64 water samples containing larvae were collected from the District of Gorakhpur. Water pH, turbidity, and oxygen level were analyzed for vector breeding index (BI). In addition, 393 serum/cerebrospinal fluid (CSF) samples of acute encephalitis syndrome (AES) suspected cases were collected from the district hospital. The various Culex species found included, Cx. quinquefasciatus (26.83%), Cx. vishnui (22.29%), Cx. pseudovishnui (20.73%), Cx. tritaeniorhynchus (12.71%), Cx. whitmorei (9.04%), and Cx. gelidus (8.25%). Highest minimum infection rate (MIR) was calculated for Cx. tritaeniorhynchus (2.32), followed by Cx. vishnui (1.98) and Cx. pseudovishnui (0.71). All the larvae samples were negative for JEV. The mean number larvae of Cx. tritaeniorhynchus and Cx. pseudovishnui was negatively correlated with pH (r = - 0.45 and r = - 0.63) and turbidity (r = - 0.30 and r = - 0.37). In contrast, positive correlation was observed in case of Cx. quinquefasciatus. A total of 41 clinical samples were found positive for JEV by IgM ELISA. The rainfall was significantly associated with Japanese encephalitis incidence and showed positive correlation to disease transmission (p = 0.02, r = 0. 66). The findings showed the rapid dissemination of JEV within a population, facilitated by different species of Culex in the region. As JE is a vaccine-preventable disease, an immunization programme, an effective vector control strategy and application of standard hygiene practices in these endemic areas could result in a considerable

  6. Seroprevalence of Cysticercus Antibodies in Japanese Encephalitis Patients in Upper Assam, India: A Hospital Based Study

    Science.gov (United States)

    Mazumdar, Himangshu; Saikia, Lahari

    2016-01-01

    Introduction Co-infection of Japanese Encephalitis (JE) and Cysticercosis is attributed mainly to the common epidemiological features between the two diseases. Not much is known about the clinical implications of one infection over the other. Aim The study aimed at establishing whether JE-Cysticercosis co-infection is prevalent in the Upper Assam districts and to explore additional details about such co-infections both clinically and epidemiologically. Materials and Methods The present study was a retrospective cross-sectional hospital based study conducted between July 2013 and June 2014 and included 272 Acute Encephalitis Syndrome (AES) patients. Out of this, 137 JE positive and 135 non-JE Acute encephalitis patients were taken as cases and controls respectively. The diagnosis of JE and Cysticercosis was established by ELISA. Statistical Analysis EpiInfo ver. 7 was used for statistical analysis. Chi-square was used and p-value < 0.05 was considered to be statistically significant. Results The association of Cysticercosis with JE was found to be statistically significant (14.6%, p = 0.0019) in the cases with reference to the controls (3.7%). Moreover, the co-infections were found to be more common in case of adults (19.32%, p = 0.0360); with males having a greater odds (5.25, p = 0.0008) of harbouring the parasite as compared to females. Conclusion The study proves that the association of Cysticercosis and JE holds true in this region. PMID:27437215

  7. Preventive strategies for frequent outbreaks of Japanese encephalitis in Northern India

    Indian Academy of Sciences (India)

    Vandana Saxena; Tapan N Dhole

    2008-11-01

    Japanese encephalitis (JE) remains the most important cause of acute viral encephalitis and continues to spread to hitherto unaffected regions like Indonesia, Pakistan and Australia. Approximately 60% of the world population inhabits JE endemic areas. Despite its restricted range mostly in the developing countries, a high annual incidence of 50,000 cases and about 10,000 deaths has been reported. Disease can be fatal in 25% cases. Magnitude of the problem is even more alarming since the survivors are left with serious long-term neuropsychiatric sequelae. Almost every two years, epidemics of JE occur in Indian subcontinent with a high mortality. JE virus infection results in different disease manifestations in host from mild subclinical febrile illness to clinical infections leading to encephalitis. No antiviral treatment is so far available for JE. The prevention of JE can be achieved by controlling the vector or by immunization regime. The vector control in the rural areas, which are the worst affected ones, is practically almost impossible. Three vaccines that have been implicated against JE include inactivated mouse brain derived, inactivated cell culture derived and cell culture derived live attenuated JE vaccine. But each has its own limitation. Currently, attempts to synthesize recombinant DNA vaccine are being made. New therapeutics are on the way of development like use of minocycline, short interfering RNA, arctigenin, rosmarinic acid, DNAzymes etc. However, the immune mechanisms that lead to JE are complex and need to be elucidated further for the development of therapeutics as well as safe and efficacious JE vaccines.

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

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    Chien-Ling Su

    2014-10-01

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

  9. A monoclonal antibody against PrM/M protein of Japanese encephalitis virus.

    Science.gov (United States)

    Hua, Rong-Hong; Bu, Zhi-Gao

    2011-10-01

    Japanese encephalitis virus (JEV) is a major public health threat in the Asia-Pacific region. The pre-membrane (PrM) protein of Japanese encephalitis virus is cleaved during maturation by the cellular protease into the structural protein M and a pr-segment. Here, we describe a procedure to generate monoclonal antibody (MAb) against JEV PrM/M protein and investigate its characteristics. Western blot analysis showed that the MAbs produced in this study were against JEV PrM/M specifically. Indirect immunofluorescence assay demonstrated that they could recognize native PrM/M protein in JEV-infected BHK-21 cells. Preliminary studies identified the epitope of the MAb with a set of synthesized overlapping peptides covering the whole length of PrM protein of JEV. The MAbs reported here may provide valuable tools for the further exploration of biological properties and functions of PrM/M protein and may also be developed for potential clinical applications.

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

    Science.gov (United States)

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

    2014-01-01

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

  11. Novel strategy for treatment of Japanese encephalitis using arctigenin, a plant lignan.

    Science.gov (United States)

    Swarup, Vivek; Ghosh, Joydeep; Mishra, Manoj Kumar; Basu, Anirban

    2008-03-01

    OBJECTIVES; To evaluate therapeutic efficacy of arctigenin in an experimental model of Japanese encephalitis (JE). Four- to 5-week-old BALB/c mice of either sex were infected intravenously with lethal dose of 3 x 10(5) pfu of Japanese encephalitis virus (JEV). By the 9th day post-infection, all untreated animals succumbed to the infection. Arctigenin was dissolved in DMSO at a concentration of 0.5 mg/mL and stored at 4 degrees C. After one day following virus inoculation, animals were given arctigenin intraperitoneally, twice daily (10 mg/kg of body weight) for next 7 days. Treatment with arctigenin provided complete protection against experimental JE. Arctigenin's neuroprotective effect was associated with marked decreases in: (i) viral load; (ii) active caspase-3 activity; (iii) reactive oxygen species and reactive nitrogen species; (iv) microgliosis and proinflammatory cytokines; (v) levels of stress-associated signalling molecules; and (vi) neuronal death. Furthermore, treatment with arctigenin also improves the behavioural outcome following JE. In conclusion, our findings provide a novel mechanistic insight into the actions of arctigenin in JE. Results from our in vivo and in vitro experiments clearly indicate that arctigenin reduced (i) viral load and viral replication within the brain, (ii) neuronal death and (iii) secondary inflammation and oxidative stress resulting from microglial activation, thereby suggesting its potential for treating JE. The antiviral, neuroprotective, anti-inflammatory and antioxidative effects of arctigenin successfully reduced the severity of disease induced by JEV.

  12. The effect of vaccination coverage and climate on Japanese encephalitis in Sarawak, Malaysia.

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    Daniel E Impoinvil

    Full Text Available BACKGROUND: Japanese encephalitis (JE is the leading cause of viral encephalitis across Asia with approximately 70,000 cases a year and 10,000 to 15,000 deaths. Because JE incidence varies widely over time, partly due to inter-annual climate variability effects on mosquito vector abundance, it becomes more complex to assess the effects of a vaccination programme since more or less climatically favourable years could also contribute to a change in incidence post-vaccination. Therefore, the objective of this study was to quantify vaccination effect on confirmed Japanese encephalitis (JE cases in Sarawak, Malaysia after controlling for climate variability to better understand temporal dynamics of JE virus transmission and control. METHODOLOGY/PRINCIPAL FINDINGS: Monthly data on serologically confirmed JE cases were acquired from Sibu Hospital in Sarawak from 1997 to 2006. JE vaccine coverage (non-vaccine years vs. vaccine years and meteorological predictor variables, including temperature, rainfall and the Southern Oscillation index (SOI were tested for their association with JE cases using Poisson time series analysis and controlling for seasonality and long-term trend. Over the 10-years surveillance period, 133 confirmed JE cases were identified. There was an estimated 61% reduction in JE risk after the introduction of vaccination, when no account is taken of the effects of climate. This reduction is only approximately 45% when the effects of inter-annual variability in climate are controlled for in the model. The Poisson model indicated that rainfall (lag 1-month, minimum temperature (lag 6-months and SOI (lag 6-months were positively associated with JE cases. CONCLUSIONS/SIGNIFICANCE: This study provides the first improved estimate of JE reduction through vaccination by taking account of climate inter-annual variability. Our analysis confirms that vaccination has substantially reduced JE risk in Sarawak but this benefit may be overestimated if

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

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    Guillaume Le Flohic

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

  14. Abrogated inflammatory response promotes neurogenesis in a murine model of Japanese encephalitis.

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    Sulagna Das

    Full Text Available BACKGROUND: Japanese encephalitis virus (JEV induces neuroinflammation with typical features of viral encephalitis, including inflammatory cell infiltration, activation of microglia, and neuronal degeneration. The detrimental effects of inflammation on neurogenesis have been reported in various models of acute and chronic inflammation. We investigated whether JEV-induced inflammation has similar adverse effects on neurogenesis and whether those effects can be reversed using an anti-inflammatory compound minocycline. METHODOLOGY/PRINCIPAL FINDINGS: Here, using in vitro studies and mouse models, we observed that an acute inflammatory milieu is created in the subventricular neurogenic niche following Japanese encephalitis (JE and a resultant impairment in neurogenesis occurs, which can be reversed with minocycline treatment. Immunohistological studies showed that proliferating cells were replenished and the population of migrating neuroblasts was restored in the niche following minocycline treatment. In vitro, we checked for the efficacy of minocycline as an anti-inflammatory compound and cytokine bead array showed that production of cyto/chemokines decreased in JEV-activated BV2 cells. Furthermore, mouse neurospheres grown in the conditioned media from JEV-activated microglia exhibit arrest in both proliferation and differentiation of the spheres compared to conditioned media from control microglia. These effects were completely reversed when conditioned media from JEV-activated and minocycline treated microglia was used. CONCLUSION/SIGNIFICANCE: This study provides conclusive evidence that JEV-activated microglia and the resultant inflammatory molecules are anti-proliferative and anti-neurogenic for NSPCs growth and development, and therefore contribute to the viral neuropathogenesis. The role of minocycline in restoring neurogenesis may implicate enhanced neuronal repair and attenuation of the neuropsychiatric sequelae in JE survivors.

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

    Science.gov (United States)

    Desprès, Philippe

    2017-01-01

    Background Japanese encephalitis virus (JEV) is the causative agent of Japanese encephalitis, the leading cause of viral encephalitis in Asia. JEV transmission cycle involves mosquitoes and vertebrate hosts. The detection of JEV RNA in a pool of Culex pipiens caught in 2010 in Italy raised the concern of a putative emergence of the virus in Europe. We aimed to study the vector competence of European mosquito populations, such as Cx. pipiens and Aedes albopictus for JEV genotypes 3 and 5. Findings After oral feeding on an infectious blood meal, mosquitoes were dissected at various times post-virus exposure. We found that the peak for JEV infection and transmission was between 11 and 13 days post-virus exposure. We observed a faster dissemination of both JEV genotypes in Ae. albopictus mosquitoes, when compared with Cx. pipiens mosquitoes. We also dissected salivary glands and collected saliva from infected mosquitoes and showed that Ae. albopictus mosquitoes transmitted JEV earlier than Cx. pipiens. The virus collected from Ae. albopictus and Cx. pipiens saliva was competent at causing pathogenesis in a mouse model for JEV infection. Using this model, we found that mosquito saliva or salivary glands did not enhance the severity of the disease. Conclusions In this study, we demonstrated that European populations of Ae. albopictus and Cx. pipiens were efficient vectors for JEV transmission. Susceptible vertebrate species that develop high viremia are an obligatory part of the JEV transmission cycle. This study highlights the need to investigate the susceptibility of potential JEV reservoir hosts in Europe, notably amongst swine populations and local water birds. PMID:28085881

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

    Science.gov (United States)

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

    2017-01-01

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

  17. Bispidine-amino acid conjugates act as a novel scaffold for the design of antivirals that block Japanese encephalitis virus replication.

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    V Haridas

    Full Text Available BACKGROUND: Japanese encephalitis virus (JEV is a major cause of viral encephalitis in South and South-East Asia. Lack of antivirals and non-availability of affordable vaccines in these endemic areas are a major setback in combating JEV and other closely related viruses such as West Nile virus and dengue virus. Protein secondary structure mimetics are excellent candidates for inhibiting the protein-protein interactions and therefore serve as an attractive tool in drug development. We synthesized derivatives containing the backbone of naturally occurring lupin alkaloid, sparteine, which act as protein secondary structure mimetics and show that these compounds exhibit antiviral properties. METHODOLOGY/PRINCIPAL FINDINGS: In this study we have identified 3,7-diazabicyclo[3.3.1]nonane, commonly called bispidine, as a privileged scaffold to synthesize effective antiviral agents. We have synthesized derivatives of bispidine conjugated with amino acids and found that hydrophobic amino acid residues showed antiviral properties against JEV. We identified a tryptophan derivative, Bisp-W, which at 5 µM concentration inhibited JEV infection in neuroblastoma cells by more than 100-fold. Viral inhibition was at a stage post-entry and prior to viral protein translation possibly at viral RNA replication. We show that similar concentration of Bisp-W was capable of inhibiting viral infection of two other encephalitic viruses namely, West Nile virus and Chandipura virus. CONCLUSIONS/SIGNIFICANCE: We have demonstrated that the amino-acid conjugates of 3,7-diazabicyclo[3.3.1]nonane can serve as a molecular scaffold for development of potent antivirals against encephalitic viruses. Our findings will provide a novel platform to develop effective inhibitors of JEV and perhaps other RNA viruses causing encephalitis.

  18. Epidemic characteristics and viral antibody level among healthy people of Japanese B encephalitis in Henan province in 2010

    Institute of Scientific and Technical Information of China (English)

    唐晓燕

    2012-01-01

    Objective To understand the epidemic characteristics and viral antibody level among healthy people of Japanese B encephalitis (JE) in Henan province in 2010. Methods A total of 433 selected JE cases in Henan province in 2010 were analyzed by descriptive epidemiological method

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

    Science.gov (United States)

    Blood samples from 105 northern pintails (Anas acuta) captured on Hokkaido, Japan were tested for antibodies to avian influenza virus (AIV), Japanese encephalitis virus (JEV) and West Nile virus (WNV) to assess possible involvement of this species in the transmission and spread of economically impor...

  20. Estimation of parameters and basic reproduction ratio for Japanese encephalitis transmission in the Philippines using sequential Monte Carlo filter

    Science.gov (United States)

    We developed a sequential Monte Carlo filter to estimate the states and the parameters in a stochastic model of Japanese Encephalitis (JE) spread in the Philippines. This method is particularly important for its adaptability to the availability of new incidence data. This method can also capture the...

  1. First Complete Genome Sequence of Genotype III Japanese Encephalitis Virus Isolated from a Stillborn Piglet in India

    Science.gov (United States)

    Desingu, P. A.; Ray, Pradeep K.; John, Jeny K.; Das, T.; Dubal, Z. B.; Rajak, K. K.; Singh, R. K.

    2017-01-01

    ABSTRACT We report here the first complete genome of the Japanese encephalitis virus (JEV) genotype III strain JEV/SW/IVRI/395A/2014, isolated from stillborn piglets in India. It shares 99% identity with strain JaOArS982 and a few other strains from Japan. PMID:28104663

  2. N-methylisatin-beta-thiosemicarbazone derivative (SCH 16 is an inhibitor of Japanese encephalitis virus infection in vitro and in vivo

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    Sriram D

    2008-05-01

    Full Text Available Abstract Background During the early and mid part of 20th century, several reports described the therapeutic effects of N-methylisatin-β-Thiosemicarbazone (MIBT against pox viruses, Maloney leukemia viruses and recently against HIV. However, their ability to inhibit flavivirus replication has not been investigated. Hence the present study was designed to evaluate the antiviral activity of 14 MIBT derivatives against Flaviviruses that are prevalent in India such as Japanese Encephalitis Virus (JEV, Dengue-2 (Den-2 and West Nile viruses (WNV. Results Amongst the fourteen Mannich bases of MIBT derivatives tested one compound – SCH 16 was able to completely inhibit in vitro Japanese encephalitis virus (JEV and West Nile virus (WNV replication. However no antiviral activity of SCH 16 was noted against Den-2 virus replication. This compound was able to inhibit 50% of the plaques (IC50 produced by JEV and WNV at a concentration of 16 μgm/ml (0.000025 μM and 4 μgm/ml (0.000006 μM respectively. Furthermore, SCH 16 at a concentration of 500 mg/kg body weight administered by oral route twice daily was able to completely (100% prevent mortality in mice challenged with 50LD50 JEV by the peripheral route. Our experiments to understand the mechanism of action suggest that SCH 16 inhibited JEV replication at the level of early protein translation. Conclusion Only one of the 14 isatin derivatives -SCH 16 exhibited antiviral action on JEV and WNV virus infection in vitro. SCH 16 was also found to completely inhibit JEV replication in vivo in a mouse model challenged peripherally with 50LD50 of the virus. These results warrant further research and development on SCH 16 as a possible therapeutic agent.

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

    Science.gov (United States)

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

    2017-09-01

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

  4. Clinical Characteristics of Severe Japanese Encephalitis: A Case Series from South Korea.

    Science.gov (United States)

    Sunwoo, Jun-Sang; Lee, Soon-Tae; Jung, Keun-Hwa; Park, Kyung-Il; Moon, Jangsup; Jung, Ki-Young; Kim, Manho; Lee, Sang Kun; Chu, Kon

    2017-08-01

    Japanese encephalitis (JE) virus is a major cause of devastating viral encephalitis, especially in Asia. Although a successful vaccination program led to its near-elimination over three decades in South Korea, the incidence of JE has increased since 2010. The present study investigated the clinical manifestations, laboratory findings, and factors affecting neurological outcomes of reemerging JE. We retrospectively reviewed medical records of laboratory-confirmed JE patients who presented with acute encephalitis syndrome at three tertiary hospitals between 2010 and 2015. A total of 17 patients with JE were identified. Their median age was 51 years, and 10 (58.5%) were men. The most common symptoms and signs were fever (94.1%), altered consciousness (94.1%), and headache (80.2%). Hyporeflexia (47.1%), seizures (35.2%), abnormal brainstem reflex (23.5%), and flaccid weakness (17.6%) were also noted. Brain imaging revealed thalamic lesions in all patients, with the hippocampus, midbrain, basal ganglia, and cerebral cortex affected to varying degrees. Sixteen patients (94.1%) required management in the intensive care unit with mechanical ventilation due to neurological deterioration. At the time of discharge, 11 (64.7%) had poor recovery, defined as Glasgow coma scale scores of less than 8, and remained ventilator dependent. Comparison between the two outcome groups indicated that midbrain involvement (P = 0.028) and rapid deterioration (P = 0.005) were associated with severe neurological sequelae. Given that JE is a vaccine-preventable disease, vaccination for adults should be considered in response to the reemergence of JE.

  5. An appraisal of clinicopathological parameters in Japanese encephalitis and changing epidemiological trends in upper Assam, India

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    Saurav Jyoti Patgiri

    2014-01-01

    Full Text Available Context: Japanese encephalitis (JE, an acute mosquito-borne viral disease, is one of the leading causes of viral encephalitis in the South-East Asian region. JE is endemic in Assam. The morbidity and mortality due to JE is significant with outbreaks every year during the monsoons. Aims: The aim was to study the clinicopathological profile of JE; to examine their role in predicting disease outcome; and to document the increase in the incidence of JE among the adult population in this region. Materials and Methods: Clinically suspected acute encephalitis syndrome (AES cases admitted in Assam Medical College and Hospital during the period of May 2011 to April 2012 were tested by JE virus specific Immunoglobulin M capture ELISA. Statistical Analysis Used: Data analysis was performed using SPSS version 16.0. Results: Out of 424 AES cases, 194 were JE positive. The occurrence of JE in adults was higher (P < 0.001 than the pediatric age group. The study recorded a high rate of renal dysfunction in JE cases. A single case of JE induced abortion and two cases of JE-neurocysticercosis co-infections were documented. Regression analysis revealed that adult population, unconsciousness, paresis and elevated cerebrospinal fluid protein level were associated with a worse prognosis in JE cases. Mortality in JE positive cases was higher than the JE negative cases (P = 0.001. Conclusion: The study attempts to highlight the role played by a combination of clinical and laboratory parameters in assessing the severity and outcome in JE and may help in directing the limited medical resources toward those that need it the most.

  6. Blockage of indoleamine 2,3-dioxygenase regulates Japanese encephalitis via enhancement of type I/II IFN innate and adaptive T-cell responses

    OpenAIRE

    2016-01-01

    Background Japanese encephalitis (JE), a leading cause of viral encephalitis, is characterized by extensive neuroinflammation following infection with neurotropic JE virus (JEV). Indoleamine 2,3-dioxygenase (IDO) has been identified as an enzyme associated with immunoregulatory function. Although the regulatory role of IDO in viral replication has been postulated, the in vivo role of IDO activity has not been fully addressed in neurotropic virus-caused encephalitis. Methods Mice in which IDO ...

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

    Directory of Open Access Journals (Sweden)

    Johanna F Lindahl

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

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

    Science.gov (United States)

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

    2014-01-20

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

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

    Science.gov (United States)

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

    2016-01-01

    Despite the increased use of vaccination in several Asian countries, Japanese Encephalitis (JE) remains the most important cause of viral encephalitis in Asia in humans with an estimated 68,000 cases annually. Considered a rural disease occurring mainly in paddy-field dominated landscapes where pigs are amplifying hosts, JE may nevertheless circulate in a wider range of environment given the diversity of its potential hosts and vectors. The main objective of this study was to assess the intensity of JE transmission to pigs in a peri-urban environment in the outskirt of Phnom Penh, Cambodia. We estimated the force of JE infection in two cohorts of 15 sentinel pigs by fitting a generalised linear model on seroprevalence monitoring data observed during two four-month periods in 2014. Our results provide evidence for intensive circulation of JE virus in a periurban area near Phnom Penh, the capital and most populated city of Cambodia. Understanding JE virus transmission in different environments is important for planning JE virus control in the long term and is also an interesting model to study the complexity of vector-borne diseases. Collecting quantitative data such as the force of infection will help calibrate epidemiological model that can be used to better understand complex vector-borne disease epidemiological cycles. PMID:27926937

  10. An evaluation of the usefulness of neuroimaging for the diagnosis of Japanese encephalitis.

    Science.gov (United States)

    Dung, N M; Turtle, Lance; Chong, W K; Mai, N T; Thao, T T; Thuy, T T; Kneen, R; Phu, N H; Wills, B; Farrar, J; Das, K; Solomon, Tom

    2009-12-01

    Japanese encephalitis virus (JEV) is estimated to cause 30–50,000 cases of encephalitis every year. The disease occurs mainly in rural Asia and is transmitted to humans from birds and pigs by mosquitoes of the genus Culex. JE is diagnosed with antibody testing of the serum and CSF, but this is not available in many hospitals. Neuroimaging abnormalities, particularly thalamic hypodensity on computed tomography (CT) and hyperintensity on T2 weighted magnetic resonance imaging (MRI) have been described in case studies, but their usefulness for diagnosing JE is not known. We have therefore evaluated the usefulness of neuroimaging (CT and MRI) for the diagnosis of JE. The findings of thalamic lesions were compared with the final serological diagnosis in a cohort of 75 patients (children and adults) with suspected CNS infections in Southern Vietnam, a JEV endemic area. Thalamic lesions on CT and/or MRI combined had sensitivity 23% (95% confidence interval 12.9–33.1%), specificity 100%, positive predictive value 100% and negative predictive value 42.1% (95% confidence interval 30.2–53.8%) for a diagnosis of JE in this cohort. Over time, the thalamic lesions resolved in some patients. One patient showed disappearance of lesions on CT followed by reappearance of the lesions some time later, known as the fogging effect. In this setting, the presence of thalamic abnormalities suggested the diagnosis of JE, but their absence did not exclude it.

  11. Japanese Encephalitis Surveillance and Immunization - Asia and Western Pacific Regions, 2016.

    Science.gov (United States)

    Heffelfinger, James D; Li, Xi; Batmunkh, Nyambat; Grabovac, Varja; Diorditsa, Sergey; Liyanage, Jayantha B; Pattamadilok, Sirima; Bahl, Sunil; Vannice, Kirsten S; Hyde, Terri B; Chu, Susan Y; Fox, Kimberley K; Hills, Susan L; Marfin, Anthony A

    2017-06-09

    Japanese encephalitis (JE) virus is the most important vaccine-preventable cause of encephalitis in the Asia-Pacific region. The World Health Organization (WHO) recommends integration of JE vaccination into national immunization schedules in all areas where the disease is a public health priority (1). This report updates a previous summary of JE surveillance and immunization programs in Asia and the Western Pacific in 2012 (2). Since 2012, funding for JE immunization has become available through the GAVI Alliance, three JE vaccines have been WHO-prequalified,* and an updated WHO JE vaccine position paper providing guidance on JE vaccines and vaccination strategies has been published (1). Data for this report were obtained from a survey of JE surveillance and immunization practices administered to health officials in countries with JE virus transmission risk, the 2015 WHO/United Nations Children's Fund Joint Reporting Form on Immunization, notes and reports from JE meetings held during 2014-2016, published literature, and websites. In 2016, 22 (92%) of 24 countries with JE virus transmission risk conducted JE surveillance, an increase from 18 (75%) countries in 2012, and 12 (50%) countries had a JE immunization program, compared with 11 (46%) countries in 2012. Strengthened JE surveillance, continued commitment, and adequate resources for JE vaccination should help maintain progress toward prevention and control of JE.

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

    Science.gov (United States)

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

    2016-06-21

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

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

    Science.gov (United States)

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

    2013-01-01

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

  14. An outbreak of Japanese encephalitis after two decades in Odisha, India.

    Science.gov (United States)

    Dwibedi, Bhagirathi; Mohapatra, Namita; Rathore, Sushil Kumar; Panda, Maheswar; Pati, Satya Sundar; Sabat, Jyotsnamayee; Thakur, Bandana; Panda, Sailendra; Kar, Shantanu Kumar

    2015-12-01

    Sudden deaths in children due to acute encephalitis syndrome (AES) from a tribal dominated district of Malkangiri in Odisha, India, was reported during September-November, 2012. The investigation was carried out to search for the possible viral aetiology that caused this outbreak. Clinico-epidemiological survey and seromolecular investigation were carried out to confirm the viral aetiology. Two hundred seventy two suspected cases with 24 deaths were observed. The patients presented with low to moderate grade fever (87%), headache (43%), vomiting (27%), cold (18%), cough (17%), body ache (15%), joint pain (15%), rash (15%), abdomen pain (9%), lethargy (5%), altered sensorium (8%), convulsion (2%), diarrhoea (3%), and haematemesis (3%). Laboratory investigation showed Japanese encephalitis virus (JEV) IgM in 13.8 per cent (13/94) in blood samples and JEV RNA in one of two cerebrospinal fluid (CSF) samples. Paddy fields close to the houses, high pig to cattle ratio, high density (33 per man hour density) of Culex vishnui mosquitoes, low socio-economic status and low health awareness in the tribal population were observed. This report confirmed the outbreak of JEV infection in Odisha after two decades.

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

    Science.gov (United States)

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

    2016-12-01

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

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

    Directory of Open Access Journals (Sweden)

    Julien Cappelle

    2016-12-01

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

  17. The prevalence of Japanese-B-Encephalitis in different species in Indonesi

    Directory of Open Access Journals (Sweden)

    Sendow I

    2000-03-01

    Full Text Available Japanese-B-Encephalitis (JE is a zoonotic disease which is characterized by encephalitis, caused by JE virus. The situation of this disease has not been known in both animals and human in Indonesia. This paper reports serological finding using competitive - ELISA to evaluate 953 serum samples, comprised of chicken, ducks, cattle, goats, horses, dogs, pigs and human from different areas in Indonesia. The antibody against JE virus was detected in animals and human sera, with prevalence varied among species and location. Cattle showed the highest prevalence of reactor (51 % while pigs, dogs and horses had the lowest reactor (11%,12% and ]4%. The highest prevalence of reactor in cattle was found in North Sumatera (86% and the lowest was found in West Java (23%. In goat, the highest prevalence of reactor was found in West Kalimantan (59% and the lowest was detected in South Sulawesi (14%. Antibody against JE virus was also detected in chicken with the highest prevalence in North Sumatera and West Kalimantan (44% and the lowest was in South Sulawesi (36%. The highest percentage of reactor in pigs was detected in South Sulawesi (50% and the lowest was detected in West Kalimantan (2%. In human, the highest prevalence of reactor was found in West Kalimantan (30% and the lowest was fowld in Irian Jaya. This result provide more information for further research, therefor the JE cases in Indonesia and its social, economic and psychological impacts can be anticipated as earlyas possible.

  18. Virus isolations from mosquitoes collected during the 1982 Japanese encephalitis epidemic in northern Thailand.

    Science.gov (United States)

    Leake, C J; Ussery, M A; Nisalak, A; Hoke, C H; Andre, R G; Burke, D S

    1986-01-01

    From 16 June to 15 August, 1982 CDC light traps were used to collect mosquitoes in the province of Kamphaengphet, N. Thailand. 353,042 mosquitoes comprising 59 species were collected and identified, and 345,173 were placed in pools for attempted virus isolation by inoculation of C6/36 Aedes albopictus mosquito cell cultures. Viruses were isolated from 63 mosquito pools. These comprised 56 flaviviruses, identified as 35 isolates of Japanese encephalitis (JE) virus strains, 18 strains of Tembusu (TEM) virus and three untyped flaviviruses (FLA); three alphaviruses, identified as the first isolates of Getah (GET) virus to have been made in Thailand; and four viruses which are still unidentified. Most virus isolates were from Culex tritaeniorhynchus mosquitoes collected in carbon dioxide baited light traps. JE virus was isolated only over a ten-day period and the last isolate was obtained one week before the peak of admission of human encephalitis cases at Kamphaengphet Provincial Hospital. Rapid screening of isolates grown on Ae. pseudoscutellaris (LSTM-AP-61) mosquito cells by indirect immunofluorescence using flavivirus group-specific and JE-specific monoclonal antibodies showed a high degree of correlation with plaque reduction neutralization tests. An antigen capture enzyme immunoassay (EIA) test successfully identified about 50% of the JE virus positive pools, but the method saved considerable processing time.

  19. An outbreak of Japanese encephalitis after two decades in Odisha, India

    Directory of Open Access Journals (Sweden)

    Bhagirathi Dwibedi

    2015-01-01

    Full Text Available Sudden deaths in children due to acute encephalitis syndrome (AES from a tribal dominated district of Malkangiri in Odisha, India, was reported during September-November, 2012. The investigation was carried out to search for the possible viral aetiology that caused this outbreak. Clinico-epidemiological survey and seromolecular investigation were carried out to confirm the viral aetiology. Two hundred seventy two suspected cases with 24 deaths were observed. The patients presented with low to moderate grade fever (87%, headache (43%, vomiting (27%, cold (18%, cough (17%, body ache (15%, joint pain (15%, rash (15%, abdomen pain (9%, lethargy (5%, altered sensorium (8%, convulsion (2%, diarrhoea (3%, and haematemesis (3%. Laboratory investigation showed Japanese encephalitis virus (JEV IgM in 13.8 per cent (13/94 in blood samples and JEV RNA in one of two cerebrospinal fluid (CSF samples. Paddy fields close to the houses, high pig to cattle ratio, high density (33 per man hour density of Culex vishnui mosquitoes, low socio-economic status and low health awareness in the tribal population were observed. This report confirmed the outbreak of JEV infection in Odisha after two decades.

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

    Science.gov (United States)

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

    2010-01-01

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

  1. Japanese viral encephalitis mimicking stroke with an initial manifestation of hemiplegia.

    Science.gov (United States)

    Chen, Huan-Wen; Ding, Liang-Wen; Lai, Chih-Cheng; Tseng, Tse-Kai; Liu, Wei-Lun

    2012-12-01

    Japanese encephalitis (JE) is an endemic disease in Taiwan. After the program to vaccinate children against JE was implemented in 1968, the incidence of JE gradually started to decrease, but it is still an important infectious disease here. Neurological manifestations in JE vary highly during the initial stage of the disease. Focal neurological symptoms, such as hemiplegia, are rarely reported. A 46-year-old male with the initial presentation of abrupt hemiplegia and fever developed mental confusion after 1 day. No bacterial pathogen was isolated from the blood or cerebrospinal fluid (CSF). A diagnosis of JE was confirmed based on the presence of JE virus-specific immunoglobulin M in the CSF and serum samples. It is necessary to consider JE when a patient presents with abrupt hemiplegia with fever followed with mental confusion and seizure, especially if the patient comes from a JE-endemic area.

  2. An enzyme immunoassay for detection of Japanese encephalitis virus-induced chemotactic cytokine

    Indian Academy of Sciences (India)

    Aditi Singh; Rajesh Kulshreshtha; Asha Mathur

    2000-03-01

    Japanese encephalitis virus (JEV) induces human peripheral blood monocytes to secrete a chemotactic cytokine [human macrophage-derived factor (hMDF)] which causes chemotaxis of neutrophils. The only known assay for hMDF cannot quantify its level in samples, so an enzyme immunoassay has been standardized for detection of hMDF and hMDF-specific antibodies in test samples. The reported enzyme linked immunosorbent assay (ELISA) was found to be sensitive (89%), specific (91%), accurate (92·2%) and reproducible and was able to detect a minimum concentration of 23 ng hMDF/ml in test samples. The chemotactic factor could be detected in JEV inoculated mouse sera and JEV infected culture fluids. Significant finding of the test was the detection of hMDF in sera of human cases of JE.

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

    Science.gov (United States)

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

    2016-03-01

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

  4. Electroencephalographic and computed X-ray tomographic findings in 99 Japanese cases of herpes simplex encephalitis

    Energy Technology Data Exchange (ETDEWEB)

    Kamei, Satoshi; Takasu, Toshiaki; Tamura, Masato; Otani, Sugishi.

    1988-10-01

    This is a retrospective analysis of electroencephalograms (EEG) and computed tomograms (CT) obtained from 99 Japanese patients with herpes simplex encephalitis (HSE). Abnormal findings of EEG were seen in 89 patients (99 %). Focal abnormality, which was frequently detected in the first EEG recording, was seen in 68 patients (76 %). Periodic synchronous discharge was observed in 25 patients (28 %). There were abnormal findings on CT in 88 patients (81 %). Low and high density areas were seen in 64 patients (73 %) and 26 patients (37 %), respectively, with the most frequent site being the temporal lobe. Mass effect was demonstrated in 33 patients (37 %). Electroencephalography detected the abnormal findings earlier than CT during the early stage of HSE in many instances. There was concordance between EEG and CT in the detection of HSE lesions in 45 patients (58 %). (Namekawa, K.).

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

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    Shu-Jen Chang

    2012-01-01

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

  6. Japanese Encephalitis in Travelers from Non-Endemic Countries, 1973–2008

    Science.gov (United States)

    Hills, Susan L.; Griggs, Anne C.; Fischer, Marc

    2010-01-01

    Japanese encephalitis (JE) is a severe disease and a risk for travelers who visit JE-endemic countries. We reviewed all published JE cases in travelers from non-endemic areas from 1973 through 2008, and assessed factors related to risk of infection. There were 55 cases that occurred in citizens of 17 countries. Age range of case-patients was 1–91 years (median = 34 years). Ten (18%) persons died and 24 (44%) had mild to severe sequelae. In a detailed risk assessment of 37 case-patients, 24 (65%) had spent ≥ 1 month in JE-endemic areas, and most had factors identified that may have increased infection risk. The estimate of overall JE risk was low, < 1 case/1 million travelers to JE-endemic countries. Nonetheless, for each traveler, a careful assessment of itinerary and activities, a decision on vaccination, and information on mosquito precautions are needed to reduce the risk of this disease. PMID:20439978

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Science.gov (United States)

    2010-01-01

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

  9. A Centralized Report on Pediatric Japanese Encephalitis Cases from Beijing Children's Hospital, 2013.

    Science.gov (United States)

    Li, Jiu Wei; Gao, Xiao Yan; Wu, Yun; Fu, Shi Hong; Tan, Xiao Juan; Cao, Yu Xi; Zhang, Wei Hua; Yin, Zun Dong; He, Ying; Li, Yi Xing; Liang, Guo Dong; Xu, Wen Bo; Fang, Fang; Wang, Huan Yu

    2016-12-01

    Fifteen pediatric cases of suspected Japanese encephalitis (JE) were reported in Beijing Children's Hospital during the late summer of 2013. The clinical manifestations in most cases included high fever, seizures, and abnormal magnetic resonance imaging findings. Twelve of 15 cases were laboratory-confirmed as JE cases by pathogen identification. Epidemiological investigations showed that five of the 12 laboratory-confirmed patients had an incomplete JE vaccination history. Follow-up investigations after discharge indicated that seven laboratory-confirmed JE patients without JE vaccinations had relatively poor prognoses, with an average Modified Rankin Scale (MRS) score of 2.6 when compared with the other five laboratory-confirmed, JE-vaccinated patients with an average MRS score of 0.5. The observation of pediatric JE cases among those with a history of JE vaccination warrants further attention. Copyright © 2016 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

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

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    V. Thenmozhi

    2014-03-01

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

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

    Science.gov (United States)

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

    2014-01-01

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

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

    Science.gov (United States)

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

    2017-02-01

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

  13. ECOLOGICAL STUDIES ON VECTORS OF MALARIA, JAPANESE ENCEPHALITIS AND FILARIASIS IN RURAL AREAS OF WEST JAVA

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    L. S. Self

    2012-09-01

    Full Text Available Penangkapan rutin nyamuk dewasa dilakukan dua kali sebulan selama 1 jam pada waktu senja pada badan kerbau, babi dan manusia dan juga dikerjakan penangkapan dengan light trap. Daerah penangkapan meliputi satu daerah dataran rendah Jakarta (semi urban dan empat daerah pedalaman di Jawa Barat yang ekologinya berbeda-beda dan dimana sawahnya 2 kali panen dalam satu tahun. Penangkapan nyamuk satu malam penuh dari jam 18.00 - 16.00 dikerjakan disalah satu daerah pedalaman tersebut. Kira-kira 90.000 specimen dari 27 species nyamuk telah ditangkap antara bulan Juni 1973 sampai bulan Juli 1974. Penangkapan pada badan binatang dan manusia menghasilkan keterangan-keterangan yang berguna, mengetahui kepadatan musiman dari vektor malaria, Japanese encephalitis dan filaria.A. aconitus adalah satu Anopheline yang terdapat dalam jumlah banyak menggigit manusia dan kepadatan yang tinggi terdapat didaerah pegunungan dimana sawahnya bertingkat-tingkat (terrace. Di Jakarta dan didaerah yang sawahnya datar nyamuk ini praktis tidak diketemukan Puncak kepadatan dari species ini berhubungan dengan musin padi yaitu pada bulan Mei dan Juni, dan pada penangkapan satu malam penuh dengan umpan manusia nyamuk ini terdapat dalam jumlah banyak pada waktu-waktu sebelum tengah malam.Cu. tritaemorrhynchus, Cu. gelidus, Cu. fuscocephalus dan Cu. vishnui menunjukkan kecen­derungan senang terhadap manusia dan babi. Untuk Cu. tritaeniorrhynchus kepadatan dalam jumlah banyak diseluruh kelima daerah penelitian. Puncak kepadatan nyamuk-nyamuk tersebut sangat pendek yaitu beberapa hari sesudah panen. Cu. vishnui lebih senang menggigit manusia bila dibandingkan species lainnya. Di Jakarta terdapat vektor Japanese encephalitis dalam jumlah yang cukup banyak sehingga kemungkinan terjadi penularan didaerah tersebut lebih besar terutama didaerah dimana diketemukan banyak peternakan babu Dua species lainnya yang banyak menggigit manusia adalah Cu. bitaeniorrhynchus dan M. uniformis.  

  14. ECOLOGICAL STUDIES ON VECTORS OF MALARIA, JAPANESE ENCEPHALITIS AND FILARIASIS IN RURAL AREAS OF WEST JAVA

    Directory of Open Access Journals (Sweden)

    L. S. Self

    2012-09-01

    Full Text Available Penangkapan rutin nyamuk dewasa dilakukan dua kali sebulan selama 1 jam pada waktu senja pada badan kerbau, babi dan manusia dan juga dikerjakan penangkapan dengan light trap. Daerah penangkapan meliputi satu daerah dataran rendah Jakarta (semi urban dan empat daerah pedalaman di Jawa Barat yang ekologinya berbeda-beda dan dimana sawahnya 2 kali panen dalam satu tahun. Penangkapan nyamuk satu malam penuh dari jam 18.00 - 16.00 dikerjakan disalah satu daerah pedalaman tersebut. Kira-kira 90.000 specimen dari 27 species nyamuk telah ditangkap antara bulan Juni 1973 sampai bulan Juli 1974. Penangkapan pada badan binatang dan manusia menghasilkan keterangan-keterangan yang berguna, mengetahui kepadatan musiman dari vektor malaria, Japanese encephalitis dan filaria.A. aconitus adalah satu Anopheline yang terdapat dalam jumlah banyak menggigit manusia dan kepadatan yang tinggi terdapat didaerah pegunungan dimana sawahnya bertingkat-tingkat (terrace. Di Jakarta dan didaerah yang sawahnya datar nyamuk ini praktis tidak diketemukan Puncak kepadatan dari species ini berhubungan dengan musin padi yaitu pada bulan Mei dan Juni, dan pada penangkapan satu malam penuh dengan umpan manusia nyamuk ini terdapat dalam jumlah banyak pada waktu-waktu sebelum tengah malam.Cu. tritaemorrhynchus, Cu. gelidus, Cu. fuscocephalus dan Cu. vishnui menunjukkan kecen­derungan senang terhadap manusia dan babi. Untuk Cu. tritaeniorrhynchus kepadatan dalam jumlah banyak diseluruh kelima daerah penelitian. Puncak kepadatan nyamuk-nyamuk tersebut sangat pendek yaitu beberapa hari sesudah panen. Cu. vishnui lebih senang menggigit manusia bila dibandingkan species lainnya. Di Jakarta terdapat vektor Japanese encephalitis dalam jumlah yang cukup banyak sehingga kemungkinan terjadi penularan didaerah tersebut lebih besar terutama didaerah dimana diketemukan banyak peternakan babu Dua species lainnya yang banyak menggigit manusia adalah Cu. bitaeniorrhynchus dan M. uniformis.  

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

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    Sarkar Arindam

    2012-11-01

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

  16. Molecular epidemiology of Japanese encephalitis in northern Vietnam, 1964-2011: genotype replacement.

    Science.gov (United States)

    Do, Loan Phuong; Bui, Trang Minh; Hasebe, Futoshi; Morita, Kouichi; Phan, Nga Thi

    2015-04-01

    Japanese encephalitis virus (JEV) is an arthropod-borne virus causing serious public health issues in Asia. JEV consists of five genotypes and recent studies have shown the emergence of JEV genotype I (GI) and its replacement of genotype III (GIII). Using an archival JEV collection, we investigated the molecular evolution of JEV in Vietnam over the last 48 years (1964-2012) in humans, mosquitoes, and pigs, within the global context. The nine JEV isolates from humans, pigs, and mosquitoes sequenced in this study and 29 sequences available in GenBank were used to analyze the envelope (E) protein of the Vietnamese JEVs. A collection of 225 cerebrospinal fluid specimens from patients with suspected Japanese encephalitis (JE) was also tested and genotyped with real-time RT-PCR. The 38 E genes identified with sequencing and nine Vietnamese JEV strains genotyped with real-time RT-PCR, belonging to two lineages, evolved in accordance with those in the rest of the world. The first GIII strain was detected in humans in Vietnam in 1964, and in mosquitoes in 1979, whereas GI strains were first detected in humans and mosquitoes in 1990 and 1994, respectively. After 2004, GI was the only genotype detected in Vietnam, demonstrating that the GIIII strains had been displaced by GI strains. Five haplotypes were identified in the Vietnamese JEVs, with SKSS predominant. The S123N and S123R substitutions in the E protein were already present in the Vietnamese JEVs. This study describes the long evolutionary history of JEV in Vietnam over 34 years, which correlates well with the global evolution of JEV. The Vietnamese GIII strains have been replaced by GI strains in mosquitoes, pigs, and humans. The predominant haplotypes of the Vietnamese strains support this genotype displacement in Vietnam. Further surveillance is required to confirm the disappearance of the GIII strains in nature and the emergence of new pathogens causing encephalitis in Vietnam, after the long-term use of JEV

  17. Hypothermia due to limbic system involvement and longitudinal myelitis in a case of Japanese encephalitis: a case report from India

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    Narayanan S

    2017-04-01

    Full Text Available Santhosh Narayanan,1 NK Thulaseedharan,1 Gomathy Subramaniam,2 Geetha Panarkandy,1 VK Shameer,1 Arathi Narayanan1 1Department of General Medicine, 2Department of Radiodiagnosis, Government Medical College, Kozhikode, Kerala, India Abstract: Japanese encephalitis (JE is an infectious encephalitis prevalent in Asia. It usually presents with fever, headache, convulsions and extrapyramidal symptoms. Limbic system involvement and hypothermia though common in autoimmune encephalitis have never been reported in JE. We report a case of an 18-year-old girl with no previous comorbidities who presented to us with a history of fever and headache for 1 week duration. She developed bilateral lateral rectus palsy and asymmetric flaccid weakness of all four limbs, after 2 days of admission, which was followed by altered sensorium and intermittent hypothermia. Neuroimaging revealed longitudinal myelitis extending from pons till the L1 level along with bilateral thalamic hemorrhage in brain. Cerebrospinal fluid (CSF was positive for IgM antibody to JE virus. She was treated with supportive measures, but she developed intractable hypothermia and seizures and succumbed to illness after 2 weeks of admission. Keywords: Japanese encephalitis, hypothermia, limbic system

  18. Cerebrospinal Fluid Biomarkers of Japanese Encephalitis [v2; ref status: indexed, http://f1000r.es/5uq

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    Nabonita Sengupta

    2015-09-01

    Full Text Available Japanese encephalitis (JE is the leading cause of viral encephalitis in Asia. Acute encephalitis syndrome (AES is a group of central nervous system (CNS disorders caused by a wide range of viruses, bacteria, fungi, chemicals and toxins. It is important to distinguish between various forms of infectious encephalitis with similar clinical manifestations in order to ensure specific and accurate diagnosis and development of subsequent therapeutic strategies. Cerebrospinal fluid (CSF is in direct contact with the CNS and hence it is considered to be an excellent source for identifying biomarkers for various neurological disorders. With the recent advancement in proteomic methodologies, the field of biomarker research has received a remarkable boost.  The present study identifies potential biomarkers for JE using a proteomics based approach. The CSF proteomes from ten patients each with JE and Non-JE acute encephalitis were analyzed by 2D gel electrophoresis followed by mass spectrometry. Vitamin D-binding protein (DBP, fibrinogen gamma chain, fibrinogen beta chain, complement C4-B, complement C3 and cytoplasmic actin were found to be significantly elevated in case of JE indicating severe disruption of the blood brain barrier and DBP can be suggested to be an important diagnostic marker.

  19. Seroprevalence of Japanese encephalitis virus using competitive enzyme linked immunosorbent assay (C-ELISA) in pigs in East Sumba, Indonesia

    OpenAIRE

    Annytha Detha; Diana A. Wuri; Ketut Santhia

    2015-01-01

    Japanese Encephalitis (JE), a vector-borne zoonotic viral disease, is mostly prevalent in Asian countries. The objective of this study was to investigate the occurence of JE virus (JEV) among pigs in East Sumba, Indonesia. Blood samples (n=52) were randomly collected from 52 apparantly healthy pigs where pig population was high in East Sumba. The samples were subjected for seroprevalence study for the presence of antibodies against JEV using competitive enzyme linked immunosorbent assay (C-EL...

  20. Persistence of antibodies six years after booster vaccination with inactivated vaccine against Japanese encephalitis.

    Science.gov (United States)

    Paulke-Korinek, Maria; Kollaritsch, Herwig; Kundi, Michael; Zwazl, Ines; Seidl-Friedrich, Claudia; Jelinek, Tomas

    2015-07-09

    Japanese Encephalitis (JE) virus occurs in wide regions of Asia with over 3 billion people living in areas at risk for JE. An estimated 68,000 clinical cases of JE occur every year, and vaccination is the most effective prophylactic measure. One internationally licensed vaccine containing the inactivated JE virus strain SA14-14-2 is Ixiaro (Valneva, Austria). According to recommendations, basic immunization consists of vaccinations on day 0, day 28, and a booster dose 12-24 months later. Protection in terms of neutralizing antibody titers has been assessed up to 12 months after the third dose of the vaccine. The current investigation was designed to evaluate antibody decline over time and to predict long-term duration of seroprotection after a booster dose. In a preceding trial, volunteers received basic immunization (day 0, day 28) and one booster dose against JE 15 months later. A follow up blood draw 6 years following their booster dose was carried out in 67 subjects. For antibody testing, a 50% plaque reduction neutralization test (PRNT50-test) was used. PRNT50 values of 10 and above are surrogate levels of protection according to WHO standards. Seventy-six months following the booster dose, 96% of the tested subjects had PRNT50 titers of 10 or higher. Geometric mean titer (GMT) was 148 (95% CI confidence interval: 107-207). Antibody titers were lower in volunteers 50 years of age and older. Vaccination history against other flaviviruses (yellow fever or tick borne encephalitis) did not significantly influence PRNT50 titers. A two-step log-linear decline model predicted protection against JE of approximately 14 years after the booster dose. Six years after a booster dose against JE, long-term protection could be demonstrated. According to our results, further booster doses should be scheduled 10 years following the first booster dose. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. A hospital-based surveillance for Japanese encephalitis in Bali, Indonesia

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    Nisalak Ananda

    2006-04-01

    Full Text Available Abstract Background Japanese encephalitis (JE is presumed to be endemic throughout Asia, yet only a few cases have been reported in tropical Asian countries such as Indonesia, Malaysia and the Philippines. To estimate the true disease burden due to JE in this region, we conducted a prospective, hospital-based surveillance with a catchment population of 599,120 children less than 12 years of age in Bali, Indonesia, from July 2001 through December 2003. Methods Balinese children presenting to any health care facility with acute viral encephalitis or aseptic meningitis were enrolled. A "confirmed" diagnosis of JE required the detection of JE virus (JEV-specific IgM in cerebrospinal fluid, whereas a diagnosis of "probable JE" was assigned to those cases in which JEV-specific IgM was detected only in serum. Results In all, 86 confirmed and 4 probable JE cases were identified. The annualized JE incidence rate was 7.1 and adjusted to 8.2 per 100,000 for children less than 10 years of age over the 2.5 consecutive years of study. Only one JE case was found among 96,920 children 10–11 years old (0.4 per 100,000. Nine children (10% died and 33 (37% of the survivors had neurological sequelae at discharge. JEV was transmitted in Bali year-round with 70% of cases in the rainy season. Conclusion JE incidence and case-fatality rates in Bali were comparable to those of other JE-endemic countries of Asia. Our findings contradict the common wisdom that JE is rare in tropical Asia. Hence, the geographical range of endemic JE is broader than previously described. The results of the study support the need to introduce JE vaccination into Bali.

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

    Science.gov (United States)

    Jones, Taff

    2009-02-01

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

  3. ACCURACY OF RAPID TEST OF STORED ACUTE PHASE SERUM FOR DIAGNOSE JAPANESE ENCEPHALITIS

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    Ida Bagus Subanada

    2013-10-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE Japanese encephalitis (JE is common viral encephalitis with high sequele and mortality. With some limitations, there are several diagnostic tool to diagnose of JE. The objecive of this study was to know the accuracy of rapid test of stored acute phase serum for diagnose of JE. We conducted diagnostic test of stored acute phase serum of encephalitis patients with MAC ELISA of cerebrospinal fluid as a gold standard. Sensitivity, specificity, positive predictive value (PPV, negative predictive value NPV, positive likelihood ratio (PLR, negative likelihood ratio (NLR, and post-test probability were calculated. This study found the prevalence of JE was 42.1%, sensitivity 15.7 % (95% CI 9.2 to 22.2%, specificity 95.7% (95% CI 92.1 to 99.3%, PPV 72.7% (95% CI 64.8 to 80.6%, NPV 60.9% (95% CI 52.2 to 69.6%, PLR 3.7, NLR 0.9, and post-test probability was 0.73. We concluded that rapid test of acute phase stored serum was insensitive but specific to diagnose of JE. /* 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:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; 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;}

  4. Japanese encephalitis associated acute encephalitis syndrome cases in West Bengal, India: A sero-molecular evaluation in relation to clinico-pathological spectrum.

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    Sarkar, Arindam; Datta, Somenath; Pathak, Bani K; Mukhopadhyay, Subhra K; Chatterjee, Shyamalendu

    2015-08-01

    Japanese encephalitis (JE) is a major public health problem in Asia and worldwide and it is responsible mainly for viral acute encephalitis syndrome (AES). The sole etiologic agent of JE is Japanese encephalitis virus (JEV). Although JE/AES cases have been regarded traditionally as a disease of children, a growing number of patients with JE/AES cases are also seen in the adult age group every year in the state of West Bengal, India in spite of vaccination. Therefore, a systematic study was performed to differentiate and characterize the clinico-pathological parameters and viral diversity among the patients of different age groups. Viral diversity was also evaluated from the JE/AES cases, depending on their disease severity. A total of 441 JE/AES cases were included in this study. By MAC-ELISA, 111 samples were found JEV IgM positive and among the IgM negative cases, 26 samples were found RT-PCR positive against JEV infection. Neck rigidity, abnormal behavior, convulsion, protein in CSF, WBC in CSF, and aspartate transaminase in blood differed significantly among the patients of pediatric-adolescent and adult group in both IgM positive and RT-PCR positive cases. Viral diversity was increased significantly in the pediatric-adolescent group compared to adult patients. Interestingly, with the rise in disease severity the viral diversity was found to be increased among the patients, irrespective of their age distribution. Based on clinico-pathological parameters and analysis of viral diversity, it can be concluded that viral diversity which occurs naturally is likely to affect disease severity, especially in the patients of pediatric-adolescent group. © 2015 Wiley Periodicals, Inc.

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

    Science.gov (United States)

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

    2014-10-01

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

  6. Sero-Molecular Epidemiology of Japanese Encephalitis in Zhejiang, an Eastern Province of China.

    Science.gov (United States)

    Pan, Jin-Ren; Yan, Ju-Ying; Zhou, Jia-Yue; Tang, Xue-Wen; He, Han-Qing; Xie, Rong-Hui; Mao, Hai-Yan; Zhang, Yan-Jun; Xie, Shu-Yun

    2016-08-01

    Sporadic Japanese encephalitis (JE) cases still have been reported in Zhejiang Province in recent years, and concerns about vaccine cross-protection and population-level immunity have been raised off and on within the public health sphere. Genotype I (GI) has replaced GIII as the dominant genotype in Asian countries during the past few decades, which caused considerable concerns about the potential change of epidemiology characteristics and the vaccine effectiveness. The aim of this study was to investigate the prevalence of JE neutralizing antibody and its waning antibody trend after live attenuated JE vaccine immunization. Additionally, this study analyzed the molecular characteristics of the E gene of Zhejiang Japanese encephalitis virus (JEV) strains, and established genetic relationships with other JEV strains. A total of 570 serum specimens were sampled from community population aged from 0 to 92 years old in Xianju county of Zhejiang Province in 2013-2014. Microseroneutralization test results were analyzed to estimate the population immunity and to observe antibody dynamics in vaccinated children. E genes of 28 JEV strains isolated in Zhejiang Province were sequenced for phylogenetic tree construction and molecular characteristics analysis with other selected strains. Positive JE neutralizing antibody rates were higher in residents ≥35 years old (81%~98%) and lower in residents <35 years old (0~57%). 7 or 8 years after the 2nd live attenuated vaccine dose, the antibodies against for 4 different strains with microseroneutralization test were decreased by 55%~73% on seropositive rates and by 25%~38% on GMTs respectively. JEV strains isolated in recent years were all grouped into GI, while those isolated in the 1980s belonged to GIII. On important amino acid sites related to antigenicity, there was no divergence between the Zhejiang JE virus strains and the vaccine strain (SA14-14-2). JE neutralizing antibody positive rates increase in age ≥10 years old

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

    Science.gov (United States)

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

    2016-04-01

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

  8. Study on DNA Immunization by Recombinants Encoding Japanese Encephalitis Virus prME and E Proteins

    Institute of Scientific and Technical Information of China (English)

    冯国和; 赵桂珍; 窦晓光; 乔光彦; 周子文

    2003-01-01

    To study the expression characteristic of Japanese encephalitis virus (JEV) prME and E proteins and the efficacy of DNA immunization by different recombinant plasmids containing JEV prME (2001 bp) and E (1500 bp) genes, tworecombinants ( pJME and pJE) containing JEV prME and E genes fused with FLAG were constructed and then transfected into HepG2 and COS-1 cells by lipnsome fusion. The expression feature of FLAG-prME (about 72 kDa) and FLAG-E (about 54 kDa) proteins in transfected cells were analyzed by Western blot and two antibody systems (anti-FLAG and anti-E).BALB/c mice were immunized with 100 μg of two kinds of recombinants by intramuscular injection, and JEV JaGAr-01strains ( 105 PFU/100 μl)were given to BALB/c mice by intraperioneal injection 3 wk after twice DNA immunization by a lethal virus challenge. BALB/c mice were observed for 21 days after challenge. 80% plaque reduction neutralization test was performed to titrate neutralization antibody before and after viral challenge. It was found that the expression of proteins associated with pJME and pJE was determined in transfected cells with anti-FLAG and a new protein of 11 kDa was detected inHepG2 and COS-1 cells transfected with pJME. Only E (53 kDa) protein was identified as transfected with pJME using antiE. Higher level of neutralization antibodies and the efficacy of protective immunity were induced with pJME immunization,and were similar to those induced by inactivated Japanese encephalitis vaccine, but were better than those induced with pJE.It concludes that the expression level from prM to E proteins of JEV is different in vitro, and the in vitro expression efficiency of pJME was better than that of piE. FLAG-prME protein expressed by pJME could be cleaved by peptidase from host.The efficacy of DNA immunization is correlated to the expression characterization of related proteins expressed in vitro.

  9. Dengue encephalitis–A rare manifestation of dengue fever

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    Deepak Madi

    2014-05-01

    Full Text Available The clinical spectrum of dengue fever ranges from asymptomatic infection to dengue shock syndrome. Dengue is classically considered a non-neurotropic virus. Neurological complications are not commonly seen in dengue. The neurological manifestations seen in dengue are encephalitis, meningitis, encephalopathy, stroke and Guillain-Barré syndrome. Dengue encephalitis is a rare disease. We report an interesting case of dengue encephalitis from Southern India. A 49-year-old gentleman presented with fever, altered sensorium and seizures. Dengue NS-1 antigen test was reactive. Dengue IgM was also positive. CSF PCR was negative for herpes simplex 1 & 2. Dengue encephalitis should be considered in the differential diagnosis of fever with altered sensorium, especially in countries like India where dengue is rampant.

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

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    Wen-yuan CAO

    2014-08-01

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

  11. Detection of antibodies against Japanese encephalitis virus in raccoons, raccoon dogs and wild boars in Japan.

    Science.gov (United States)

    Ohno, Yoshito; Sato, Hiroshi; Suzuki, Kazuo; Yokoyama, Mayumi; Uni, Shigehiko; Shibasaki, Takahiro; Sashika, Mariko; Inokuma, Hisashi; Kai, Kazushige; Maeda, Ken

    2009-08-01

    Japanese encephalitis virus (JEV) infects numerous animal species including humans, horses and pigs. In this study, antibodies against JEV in feral raccoons (Procyon lotor), wild boars (Sus scrofa) and raccoon dogs (Nyctereutes procyonoides) in Japan were examined. The results showed that 40.7% (22 out of 54), 64.5% (40 out of 62), 69.1% (47 out of 68) and 0% (0 out of 20) of raccoons in Hyogo, Osaka, Wakayama and Hokkaido, respectively, had virus-neutralizing antibodies against JEV. In addition, 83.3% (30 out of 36) of wild boars and 63.2% (12 out of 19) of raccoon dogs in Wakayama were seropositive for JEV. There were no significant differences in seroprevalence of JEV between males and females or between adults and juveniles in these wild animals. JEV seroprevalence was compared between 37 raccoons and 30 wild boars captured in a limited period (November 2007 to February 2008), and we found that wild boars (86.7%) were significantly more seropositive for JEV antibody than raccoons (59.5%). In conclusion, JEV was prevalent in wild mammals, indicating that the possibility of JEV infection in humans may still be high in Japan. In addition, these wild animals may be good sentinels to estimate JEV infection risk in residents, as they live near humans and are not vaccinated.

  12. Seroconversion to Japanese Encephalitis Virus among U.S. Infantry Forces in Korea

    Science.gov (United States)

    Eick-Cost, Angelia A.; Hu, Zheng; Klein, Terry A.; Putnak, Robert J.; Jarman, Richard G.

    2015-01-01

    Japanese encephalitis virus (JEV) is endemic in the Republic of Korea (ROK), posing a medical threat to more than 29,000 U.S. Forces military personnel currently deployed in the ROK. The objective of this study was to provide data on the risk of JEV exposure among U.S. Forces in the ROK. One thousand U.S. Army Soldiers were randomly selected for the study from the cohort of infantry Soldiers deployed in the ROK for a period of at least 330 days from 2008 to 2011. Pre- and post-deployment serum specimens were tested for the presence of JEV antibodies by plaque reduction neutralization test. A total of 2/1,000 (0.2%) U.S. Army Soldiers post-deployment specimens tested positive for JEV antibody. Results from the pre-deployment specimens indicated one true seroconversion and one with titers suggestive of a JEV infection. These results indicate a low, but nonzero risk of JEV exposure among U.S. Army Soldiers in the ROK. PMID:26240157

  13. Modeling the distribution of Culex tritaeniorhynchus to predict Japanese encephalitis distribution in the Republic of Korea

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    Penny Masuoka

    2010-11-01

    Full Text Available Over 35,000 cases of Japanese encephalitis (JE are reported worldwide each year. Culex tritaeniorhynchus is the primary vector of the JE virus, while wading birds are natural reservoirs and swine amplifying hosts. As part of a JE risk analysis, the ecological niche modeling programme, Maxent, was used to develop a predictive model for the distribution of Cx. tritaeniorhynchus in the Republic of Korea, using mosquito collection data, temperature, precipitation, elevation, land cover and the normalized difference vegetation index (NDVI. The resulting probability maps from the model were consistent with the known environmental limitations of the mosquito with low probabilities predicted for forest covered mountains. July minimum temperature and land cover were the most important variables in the model. Elevation, summer NDVI (July-September, precipitation in July, summer minimum temperature (May-August and maximum temperature for fall and winter months also contributed to the model. Comparison of the Cx. tritaeniorhynchus model to the distribution of JE cases in the Republic of Korea from 2001 to 2009 showed that cases among a highly vaccinated Korean population were located in high-probability areas for Cx. tritaeniorhynchus. No recent JE cases were reported from the eastern coastline, where higher probabilities of mosquitoes were predicted, but where only small numbers of pigs are raised. The geographical distribution of reported JE cases corresponded closely with the predicted high-probability areas for Cx. tritaeniorhynchus, making the map a useful tool for health risk analysis that could be used for planning preventive public health measures.

  14. The prM-independent packaging of pseudotyped Japanese encephalitis virus.

    Science.gov (United States)

    Lee, Hee Jung; Min, Kyung-Il; Lee, Jungeun; Kang, Sin-Hyung; Jeon, Wonkyung; Nam, Jae Hwan; Ju, Young Ran; Kim, Young Bong

    2009-07-30

    As noted in other flaviviruses, the envelope (E) protein of Japanese encephalitis virus (JEV) interacts with a cellular receptor and mediates membrane fusion to allow viral entry into target cells, thus eliciting neutralizing antibody response. The formation of the flavivirus prM/E complex is followed by the cleavage of precursor membrane (prM) and membrane (M) protein by a cellular signalase. To test the effect of prM in JEV biology, we constructed JEV-MuLV pseudotyped viruses that express the prM/E protein or E only. The infectivity and titers of JEV pseudotyped viruses were examined in several cell lines. We also analyzed the neutralizing capacities with anti-JEV sera from JEV-immunized mice. Even though prM is crucial for multiple stages of JEV biology, the JEV-pseudotyped viruses produced with prM/E or with E only showed similar infectivity and titers in several cell lines and similar neutralizing sensitivity. These results showed that JEV-MuLV pseudotyped viruses did not require prM for production of infectious pseudotyped viruses.

  15. Small noncoding RNA modulates japanese encephalitis virus replication and translation in trans

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    Fan Yi-Hsin

    2011-11-01

    Full Text Available Abstract Background Sequence and structural elements in the 3'-untranslated region (UTR of Japanese encephalitis virus (JEV are known to regulate translation and replication. We previously reported an abundant accumulation of small subgenomic flaviviral RNA (sfRNA which is collinear with the highly conserved regions of the 3'-UTR in JEV-infected cells. However, function of the sfRNA in JEV life cycle remains unknown. Results Northern blot and real-time RT-PCR analyses indicated that the sfRNA becomes apparent at the time point at which minus-strand RNA (antigenome reaches a plateau suggesting a role for sfRNA in the regulation of antigenome synthesis. Transfection of minus-sense sfRNA into JEV-infected cells, in order to counter the effects of plus-sense sfRNA, resulted in higher levels of antigenome suggesting that the presence of the sfRNA inhibits antigenome synthesis. Trans-acting effect of sfRNA on JEV translation was studied using a reporter mRNA containing the luciferase gene fused to partial coding regions of JEV and flanked by the respective JEV UTRs. In vivo and in vitro translation revealed that sfRNA inhibited JEV translation. Conclusions Our results indicate that sfRNA modulates viral translation and replication in trans.

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

    Science.gov (United States)

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

    2015-05-01

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

  17. Recurrence of Japanese Encephalitis Epidemic in Wuhan, China, 2009–2010

    Science.gov (United States)

    Zhu, Zerong; Tian, Junhua; Zhou, Yu; Zhang, Xiaoyong; Zheng, Xin

    2013-01-01

    Background Japanese encephalitis (JE) was once epidemic in most areas of China, including Wuhan, a city located in the central part of China. The incidence of JE dramatically decreased due to nationwide immunization with the live attenuated JE virus (JEV) vaccine, and no JE cases were reported during 2005–2008 in Wuhan. In 2009 and 2010, 31 JE cases reoccurred in this area. In this study, we investigated the causes of JE recurrence. Methods and Findings All JE cases were laboratory-confirmed by detecting the JEV-specific IgM antibody with an IgM-capture enzyme-linked immunosorbent assay (ELISA). All patients were children between 2 months and 9 years of age with a median age of 2 years. Of the 31 cases, 9 had received one or two doses of the JEV vaccine, 11 had not been immunized previously with the JEV vaccine, and 11 had an unclear immunization history. Through reverse transcription polymerase chain reaction (RT-PCR), sequencing, and phylogenetic analysis, two new strains of JEV were isolated from Culex tritaeniorhynchus and identified as genotype 1 JEV, rather than genotype 3, which circulated in this area previously. Conclusions Vaccine failure or missed vaccination may have caused JE recurrence. Local centers for disease control and prevention need to improve immunization coverage, and the efficacy of the JE vaccine needs to be reevaluated in a population at risk for disease. PMID:23326348

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

    Science.gov (United States)

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

    2015-09-01

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

  19. A KDEL Retrieval System for ER-Golgi Transport of Japanese Encephalitis Viral Particles.

    Science.gov (United States)

    Wang, Robert Y L; Wu, Yu-Jen; Chen, Han-Shan; Chen, Chih-Jung

    2016-02-05

    Evidence has emerged that RNA viruses utilize the host secretory pathway for processing and trafficking mature viral particles and for exiting the infected cells. Upon completing the complex assembly process, the viral particles take advantage of the cellular secretory trafficking machinery for their intracellular trafficking toward the Golgi organelle and budding or export of virions. In this study, we showed that Japanese encephalitis virus (JEV)-induced extracellular GRP78 contains no KDEL motif using an anti-KDEL-specific antibody. Overexpression of the KDEL-truncated GRP78 in the GPR78 knocked down cells significantly reduced JEV infectivity, suggesting that the KDEL motif is required for GRP78 function in the release of JE viral particles. In addition, we demonstrated the KDELR protein, an ER-Golgi retrieval system component, is associated with viral envelope proteins and is engaged in the subcellular localization of viral particles in Golgi. More importantly, accumulation of intracellular virions was observed in the KDELR knocked down cells, indicating that the KDELR protein mediated the intracellular trafficking of JE viral particles. Altogether, we demonstrated that intracellular trafficking of JE assembled viral particles was mediated by the host ER-Golgi retrieval system prior to exit by the secretory pathway.

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

    Science.gov (United States)

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

    2012-01-01

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

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

    Science.gov (United States)

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

    2015-01-01

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

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

    Science.gov (United States)

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

    2016-10-01

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

  3. Similarities and differences of MR findings between Japanese encephalitis and Wilson's disease

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    Saha, Manash; Kumar, Sunil; Gupta, Rakesh K. [Department of Radiodiagnosis, Sanjay Gandhi Post-Graduate Institute of Medical Sciences, Lucknow (India); Das, Ashish [Department of Neurology, Sanjay Gandhi Post-Graduate Institute of Medical Sciences, Lucknow (India)

    2002-04-01

    Although Japanese Encephalitis (JE) and Wilson's disease (WD) are different entities, MR findings in both these conditions are quite similar. The purpose of this retrospective study was to find out the similarities and differences between JE and WD on MR imaging. The study group comprised 25 proven cases of JE and 10 cases of WD. Spin echo (SE) TI- and T2-weighted imaging was performed on a 1.5-T MR system. Fourteen of these 35 cases (10 JE, 4 WD) were also examined using T1-weighted magnetization transfer (MT) SE sequence before and after contrast administration. Although both JE and WD showed similar topographical distribution of lesions, predominant involvement of the basal ganglia and thalami, there were some differences. Brain stem lesion was more frequent for WD than for JE, and posteromedial part of the thalami was spared in WD. The lesion characteristics were also different between both; in WD mixed intensity in the basal ganglia and hyperintense linear rim at the peripheral putamen was observed frequently, whereas hyperintense basal ganglia on T2-weighted images, subacute hemorrhage in the thalami and meningeal enhancement were seen only in the patients with JE. These characteristic lesion criteria may help in differentiation of JE from WD on MR imaging. (orig.)

  4. Potential chemotherapeutic targets for Japanese encephalitis: current status of antiviral drug development and future challenges.

    Science.gov (United States)

    Ishikawa, Tomohiro; Konishi, Eiji

    2015-01-01

    Japanese encephalitis (JE) remains a public health threat in Asia. Although several vaccines have been licensed, ∼ 67,900 cases of the disease are estimated to occur annually, probably because the vaccine coverage is low. Therefore, effective antiviral drugs are required to control JE. However, no licensed anti-JE drugs are available, despite extensive efforts to develop them. We provide a general overview of JE and JE virus, including its transmission cycle, distribution, structure, replication machinery, immune evasion mechanisms and vaccines. The current situation in antiviral drug development is then reviewed and future perspectives are discussed. Although the development of effective anti-JE drugs is an urgent issue, only supportive care is currently available. Recent progress in our understanding of the viral replication machinery and immune evasion strategies has identified new targets for anti-JE drug development. To date, most candidate drugs have only been evaluated in single-drug formulations, and efficient drug delivery to the CNS has virtually not been considered. However, an effective anti-JE treatment is expected to be achieved with multiple-drug formulations and a targeted drug delivery system in the near future.

  5. The prM-independent packaging of pseudotyped Japanese encephalitis virus

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    Ju Young

    2009-07-01

    Full Text Available Abstract As noted in other flaviviruses, the envelope (E protein of Japanese encephalitis virus (JEV interacts with a cellular receptor and mediates membrane fusion to allow viral entry into target cells, thus eliciting neutralizing antibody response. The formation of the flavivirus prM/E complex is followed by the cleavage of precursor membrane (prM and membrane (M protein by a cellular signalase. To test the effect of prM in JEV biology, we constucted JEV-MuLV pseudotyped viruses that express the prM/E protein or E only. The infectivity and titers of JEV pseudotyped viruses were examined in several cell lines. We also analyzed the neutralizing capacities with anti-JEV sera from JEV-immunized mice. Even though prM is crucial for multiple stages of JEV biology, the JEV-pseudotyped viruses produced with prM/E or with E only showed similar infectivity and titers in several cell lines and similar neutralizing sensitivity. These results showed that JEV-MuLV pseudotyped viruses did not require prM for production of infectious pseudotyped viruses.

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

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    Jing Zhou

    2017-01-01

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

  7. Modeling the distribution of Culex tritaeniorhynchus to predict Japanese encephalitis distribution in the Republic of Korea.

    Science.gov (United States)

    Masuoka, Penny; Klein, Terry A; Kim, Heung-Chul; Claborn, David M; Achee, Nicole; Andre, Richard; Chamberlin, Judith; Small, Jennifer; Anyamba, Assaf; Lee, Dong-Kyu; Yi, Suk H; Sardelis, Michael; Ju, Young-Ran; Grieco, John

    2010-11-01

    Over 35,000 cases of Japanese encephalitis (JE) are reported worldwide each year. Culex tritaeniorhynchus is the primary vector of the JE virus, while wading birds are natural reservoirs and swine amplifying hosts. As part of a JE risk analysis, the ecological niche modeling programme, Maxent, was used to develop a predictive model for the distribution of Cx. tritaeniorhynchus in the Republic of Korea, using mosquito collection data, temperature, precipitation, elevation, land cover and the normalized difference vegetation index (NDVI). The resulting probability maps from the model were consistent with the known environmental limitations of the mosquito with low probabilities predicted for forest covered mountains. July minimum temperature and land cover were the most important variables in the model. Elevation, summer NDVI (July-September), precipitation in July, summer minimum temperature (May-August) and maximum temperature for fall and winter months also contributed to the model. Comparison of the Cx. tritaeniorhynchus model to the distribution of JE cases in the Republic of Korea from 2001 to 2009 showed that cases among a highly vaccinated Korean population were located in high-probability areas for Cx. tritaeniorhynchus. No recent JE cases were reported from the eastern coastline, where higher probabilities of mosquitoes were predicted, but where only small numbers of pigs are raised. The geographical distribution of reported JE cases corresponded closely with the predicted high-probability areas for Cx. tritaeniorhynchus, making the map a useful tool for health risk analysis that could be used for planning preventive public health measures.

  8. Isolation of Japanese encephalitis virus from clinical specimens using a continuous mosquito cell line.

    Science.gov (United States)

    Leake, C J; Burke, D S; Nisalak, A; Hoke, C H

    1986-09-01

    During the 1983 Japanese encephalitis (JE) epidemic in northern Thailand, we systematically attempted to isolate JE virus (JEV) from clinical specimens collected from 49 consecutive JE patients at 1 provincial hospital. Fresh acute plasma and cerebrospinal fluid (CSF) samples and postmortem brain samples were immediately inoculated onto cultured monolayers of Aedes pseudoscutellaris (LSTM-AP-61) cells which had been shipped to the epidemic site. None of 49 plasma samples yielded virus. None of 30 fresh CSF samples from nonfatal cases yielded virus, but 5 of 15 (33%) CSF samples from fatal cases did. Inoculation of fresh brain specimens obtained at autopsy yielded virus in every case attempted (7 of 7), whereas postmortem needle biopsy specimens of brain yielded virus in only 1 of 4 cases. Isolates were most frequently successful using thalamic tissue (6 of 7 cases), but isolates were also commonly obtained from frontal cortex (4/7), occipital cortex (4/7), cerebellum (4/7), medulla (4/7) and pons (2/7).

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

    Science.gov (United States)

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

    2016-01-01

    During the last 20 years, the epidemiology of Japanese encephalitis virus (JEV) has changed significantly in its endemic regions due to the gradual displacement of the previously dominant genotype III (GIII) with clade b of GI (GI-b). Whilst there is only limited genetic difference distinguishing the two GI clades (GI-a and GI-b), GI-b has shown a significantly wider and more rapid dispersal pattern in several regions in Asia than the GI-a clade, which remains restricted in its geographic distribution since its emergence. Although previously published molecular epidemiological evidence has shown distinct phylodynamic patterns, characterization of the two GI clades has only been limited to in vitro studies. In this study, Culex quinquefasciatus, a known competent JEV mosquito vector species, was orally challenged with three JEV strains each representing GI-a, GI-b, and GIII, respectively. Infection and dissemination were determined based on the detection of infectious viruses in homogenized mosquitoes. Detection of JEV RNA in mosquito saliva at 14 days post infection indicated that Cx. quinquefasciatus can be a competent vector species for both GI and GIII strains. Significantly higher infection rates in mosquitoes exposed to the GI-b and GIII strains than the GI-a strain suggest infectivity in arthropod vectors may lead to the selective advantage of previously and currently dominant genotypes. It could thus play a role in enzootic transmission cycles for the maintenance of JEV if this virus were ever to be introduced into North America. PMID:27706157

  10. Cell Type-Dependent RNA Recombination Frequency in the Japanese Encephalitis Virus

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    Wei-Wei Chiang

    2014-01-01

    Full Text Available Japanese encephalitis virus (JEV is one of approximately 70 flaviviruses, frequently causing symptoms involving the central nervous system. Mutations of its genomic RNA frequently occur during viral replication, which is believed to be a force contributing to viral evolution. Nevertheless, accumulating evidences show that some JEV strains may have actually arisen from RNA recombination between genetically different populations of the virus. We have demonstrated that RNA recombination in JEV occurs unequally in different cell types. In the present study, viral RNA fragments transfected into as well as viral RNAs synthesized in mosquito cells were shown not to be stable, especially in the early phase of infection possibly via cleavage by exoribonuclease. Such cleaved small RNA fragments may be further degraded through an RNA interference pathway triggered by viral double-stranded RNA during replication in mosquito cells, resulting in a lower frequency of RNA recombination in mosquito cells compared to that which occurs in mammalian cells. In fact, adjustment of viral RNA to an appropriately lower level in mosquito cells prevents overgrowth of the virus and is beneficial for cells to survive the infection. Our findings may also account for the slower evolution of arboviruses as reported previously.

  11. Cell type-dependent RNA recombination frequency in the Japanese encephalitis virus.

    Science.gov (United States)

    Chiang, Wei-Wei; Chuang, Ching-Kai; Chao, Mei; Chen, Wei-June

    2014-01-01

    Japanese encephalitis virus (JEV) is one of approximately 70 flaviviruses, frequently causing symptoms involving the central nervous system. Mutations of its genomic RNA frequently occur during viral replication, which is believed to be a force contributing to viral evolution. Nevertheless, accumulating evidences show that some JEV strains may have actually arisen from RNA recombination between genetically different populations of the virus. We have demonstrated that RNA recombination in JEV occurs unequally in different cell types. In the present study, viral RNA fragments transfected into as well as viral RNAs synthesized in mosquito cells were shown not to be stable, especially in the early phase of infection possibly via cleavage by exoribonuclease. Such cleaved small RNA fragments may be further degraded through an RNA interference pathway triggered by viral double-stranded RNA during replication in mosquito cells, resulting in a lower frequency of RNA recombination in mosquito cells compared to that which occurs in mammalian cells. In fact, adjustment of viral RNA to an appropriately lower level in mosquito cells prevents overgrowth of the virus and is beneficial for cells to survive the infection. Our findings may also account for the slower evolution of arboviruses as reported previously.

  12. Neurological sequelae of hospitalized Japanese encephalitis cases in Gansu province, China.

    Science.gov (United States)

    Yin, Zundong; Wang, Xuxia; Li, Li; Li, Hui; Zhang, Xiaoshu; Li, Junhong; Ning, Guijun; Li, Fengqin; Liang, Xuefeng; Gao, Li; Liang, Xiaofeng; Li, Yixing

    2015-06-01

    We conducted a follow-up survey for 55 Japanese encephalitis (JE) cases 1-2 years after hospital discharge in Gansu province, China. Community-, education-, and gender-matched healthy individuals without history of neurologic disease were selected as the comparison group. All subjects received neurological examination, intelligence quotient (IQ) measurement, adaptive behavior measurement, and Wechsler memory scale (WMS) assessment. We found 43.6% JE cases had at least one nervous system sequelae compared with 3.6% healthy individuals. Among JE cases, 22.4% had subnormal IQ, 18.4% subnormal verbal IQ (VIQ), 20.4% subnormal performance IQ (PIQ), and 78.4% had subnormal memory quotient (MQ). Among healthy individuals, 2.0% had subnormal IQ, VIQ, or PIQ and 8.1% had subnormal MQ. Among adult JE cases, 47.8% and 39.1% had adaptive behavior impairments and intellectual disability, respectively, compared with 18.8% and 9.7% among young cases, respectively. The results showed both adult and young surviving JE cases had significant neurological sequelae and mental disability 1-2 years after discharged. © The American Society of Tropical Medicine and Hygiene.

  13. Prevalence of Japanese encephalitis virus antibody in sika deer (Cervus nippon) in Odaigahara, Kii Peninsula, Japan

    OpenAIRE

    斉藤, 美加; 荒木, 良太; 鳥居, 春己; 浅川, 満彦

    2015-01-01

    日本脳炎ウイルス(JEV)感染リスク評価の一環で, 2009年と 2010年に紀伊半島大台ヶ原で捕獲されたニホンジカ Cervus nippon(以下,シカ)の JEV抗体保有状況を調査した。JEV,Oki431S株に対し 87頭中 9頭(10.3%)が,Beijing-1株に対し 1頭( 1.1%)が抗体を保有し,年齢階層が高くなるに従い,抗体保有率の上昇傾向がみられた。これらより,シカに JEVに対する感受性がある事,大台ヶ原で JEV感染環が成立し, JEVの活動は低いが常在している地域である事が強く示唆された。 Sero-epidemiological study of Japanese encephalitis virus was conducted on sika deer (Cervus nippon) captured in Odaigahara, a forested area, on Kii peninsula, Japan, in 2009 and 2010. Nine (10.3%) out of 87 deer had neutralizing anti...

  14. Impact of weather variables on mosquitoes infected with Japanese encephalitis virus in Kurnool district, Andhra Pradesh

    Institute of Scientific and Technical Information of China (English)

    Srinivasa Rao Mutheneni; Hari Krishna Nayanoori; Arunachalam Natarajan; Prashant Goswami

    2012-01-01

    ABSTRACT Objective:To assess the virus infection in mosquitoes during different seasons and correlated with various climatic factors.Methods:The field collected vectors were screened for Japanese encephalitis (JE) virus after dessication usingELISAmethod. Most of the positive pools were recorded fromCulex tritaeniorhynchus (Cx. tritaeniorhynchus) andCulex.gelidus(Cx. gelidus) duringJE transmission season (winter) and some positive pools were also reported during nonJE transmission periods (i.e. summer and rainy seasons).Results: The minimum infection rates(MIR) of1.75 fromCx. tritaeniorhynchus and0.17fromCx. gelidus has been reported in the year2002 at the beginning of the study and the values were found nil at the end of the study(2006) from the study areas of Kurnool district.Conclusions:From this study it is noted thatMIR ofCx. gelidus andCx. tritaeniorhynchus were modulated by various meteorological parameters. The mosquito vector abundance increases after the monsoon period (winter) and lowest in dry season (summer). Similarly,MIR fluctuated between seasons with higherMIR recorded after monsoon period and lower in the rest of season. Impact of these metrological parameters in JE virus infected mosquitoes is discussed in this paper.

  15. Dengue

    National Research Council Canada - National Science Library

    Whitehorn, James; Farrar, Jeremy

    2010-01-01

    Dengue is a vector-borne viral infection that endangers an estimated 2.5 billion people. Disease caused by dengue ranges from a relatively minor febrile illness to a life-threatening condition characterized by extensive capillary leak...

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

    Science.gov (United States)

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

    2015-08-01

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

  17. Viral Infection of the Central Nervous System and Neuroinflammation Precede Blood-Brain Barrier Disruption during Japanese Encephalitis Virus Infection.

    Science.gov (United States)

    Li, Fang; Wang, Yueyun; Yu, Lan; Cao, Shengbo; Wang, Ke; Yuan, Jiaolong; Wang, Chong; Wang, Kunlun; Cui, Min; Fu, Zhen F

    2015-05-01

    Japanese encephalitis is an acute zoonotic, mosquito-borne disease caused by Japanese encephalitis virus (JEV). Japanese encephalitis is characterized by extensive inflammation in the central nervous system (CNS) and disruption of the blood-brain barrier (BBB). However, the pathogenic mechanisms contributing to the BBB disruption are not known. Here, using a mouse model of intravenous JEV infection, we show that virus titers increased exponentially in the brain from 2 to 5 days postinfection. This was accompanied by an early, dramatic increase in the level of inflammatory cytokines and chemokines in the brain. Enhancement of BBB permeability, however, was not observed until day 4, suggesting that viral entry and the onset of inflammation in the CNS occurred prior to BBB damage. In vitro studies revealed that direct infection with JEV could not induce changes in the permeability of brain microvascular endothelial cell monolayers. However, brain extracts derived from symptomatic JEV-infected mice, but not from mock-infected mice, induced significant permeability of the endothelial monolayer. Consistent with a role for inflammatory mediators in BBB disruption, the administration of gamma interferon-neutralizing antibody ameliorated the enhancement of BBB permeability in JEV-infected mice. Taken together, our data suggest that JEV enters the CNS, propagates in neurons, and induces the production of inflammatory cytokines and chemokines, which result in the disruption of the BBB. Japanese encephalitis (JE) is the leading cause of viral encephalitis in Asia, resulting in 70,000 cases each year, in which approximately 20 to 30% of cases are fatal, and a high proportion of patients survive with serious neurological and psychiatric sequelae. Pathologically, JEV infection causes an acute encephalopathy accompanied by BBB dysfunction; however, the mechanism is not clear. Thus, understanding the mechanisms of BBB disruption in JEV infection is important. Our data demonstrate

  18. Dengue

    Science.gov (United States)

    Dengue is an infection caused by a virus. You can get it if an infected mosquito bites you. Dengue does not spread from person to person. It ... the world. Outbreaks occur in the rainy season. Dengue is rare in the United States. Symptoms include ...

  19. Japanese encephalitis (JE) part II: 14 years' follow-up of survivors.

    Science.gov (United States)

    Sarkari, N B S; Thacker, A K; Barthwal, S P; Mishra, V K; Prapann, Shiv; Srivastava, Deepak; Sarkari, M

    2012-01-01

    Japanese encephalitis, the commonest Arbovirus encephalitis, has been endemic in many parts of Asia, the Pacific Islands, and India; also, there have been many epidemics. Most of the post JE cases have been associated with neurological and neuropsychiatric deficits but have not been properly classified and followed. Practically all the previous studies were in children or young adults. The aim of this study, involving only adult cases, the largest ever being reported, has been to follow the 688/1,199 survivors of JE patients out of 1,282 of acute cases admitted during four epidemics for a period of 14 years after properly classifying the sequelae. This prospective study was conducted in B.R.D. Medical College Gorakhpur (India), involving 665/688 post JE cases with neuropsychiatric deficits from four epidemics of 1978, 1980, 1988 and 1989 which were properly classified in nine groups. While the first epidemic of 1978 was being studied, more disastrous episodes flared up and the patients were subsequently added. Hence, the total duration of this prospective study was from November 1978 to December 2003. There were 14 defaulted initially from 688 followed (23/688 without sequelae and 665/688 with neuropsychiatric deficits), and later 130 were lost from time to time at various stages of follow up. Four out of 23/688 discharged without any deficit had to be readmitted for bizarre movements, assaultative behaviour and euphoria without fever and altered sensorium. All of them improved by symptomatic treatment. Progressive improvement occurred in all the parameters consisting of psychological disturbances, higher cerebral dysfunction, speech disorders (dysphonia, dysarthria, dysphasias, apraxia and agnosia), extra pyramidal, pyramidal features, and hypothalamic disturbances, cranial nerves including pupils and fundi and seizures. Maximum cases improved between 6 months (55%) to 1 year (78%). Only some features improved between 5 to 14 years. Four patients of hemiplegia

  20. Molecular phylogenetic and positive selection analysis of Japanese encephalitis virus strains isolated from pigs in China.

    Science.gov (United States)

    Liu, Wen-Jun; Zhu, Ming; Pei, Jing-Jing; Dong, Xiao-Ying; Liu, Wei; Zhao, Ming-Qiu; Wang, Jia-Ying; Gou, Hong-Chao; Luo, Yong-Wen; Chen, Jin-Ding

    2013-12-26

    Japanese encephalitis virus (JEV) is one of the most important virus which causes encephalitis. This disease is most prevalent in the south, southeast and the east region of Asia. In this study, two JEV strains, named JEV/SW/GD/01/2009 and JEV/SW/GZ/09/2004, were isolated from aborted fetuses and seminal fluid of pigs in China. To determine the characteristic of these virus isolates, the virulence of two newly JEV isolates was investigated, the result evidenced that the JEV/SW/GD/01/2009 did not kill mice, while the JEV/SW/GZ/09/2004 displayed neurovirulence with 0.925log10 p.f.u./LD50. Additionally, the full genome sequences of JEV were determined and compared with other known JEV strains. Results demonstrated that the genome of two JEV isolates was 10,976 nucleotides (nt) in length. As compared to the Chinese vaccine strain SA14-14-2, the JEV/SW/GD/01/2009 and the JEV/SW/GZ/09/2004 showed 99.7% and 97.5% identity at the nucleotide level, 99.6% and 96.7% identity at the amino acid level, respectively. Phylogenetic analysis, based on the full-length genome revealed that two JEV isolates were all clustered into genotype III compared to the reference strains. Furthermore, selection analyses revealed that dominant selective pressure acting on the JEV genome was purifying selection. Four sites under positive selection were identified: codon 521 (amino acid E-227), 2296 (amino acid NS4b-24), 3048 (amino acid NS5-521) and 3055 (amino acid NS5-528). Amino acid E-227 was proved to be related to neurovirulence. Taken together, the molecular epidemiology and functional of positively selected amino acid sites of two newly JEV isolates were fully understood, which might be helpful to predict possible changes in virulence. Copyright © 2013 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

    Takamatsu, Yuki; Uchida, Leo; Morita, Kouichi

    2015-08-01

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

  2. Pathogenesis of Japanese encephalitis virus infection in a golden hamster model and evaluation of flavivirus cross-protective immunity.

    Science.gov (United States)

    Bosco-Lauth, Angela; Mason, Gary; Bowen, Richard

    2011-05-01

    Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus endemic to Southeast Asia and surrounding Pacific Islands, and it has most recently emerged in northern Australia. JEV is closely related to West Nile virus (WNV) and St. Louis encephalitis virus (SLEV), both endemic to the United States. In the event that JEV is introduced into the Americas, it will be important to determine whether immunity to WNV or SLEV might afford protection from infection and development of viremia in susceptible hosts. We investigated a hamster model of JEV infection and showed that a large fraction of animals infected with either a genotype I or III isolate of virus developed viremia and encephalitic lesions without clinical signs of disease. Using this model, we showed that prior infection with WNV or SLEV, vaccination using a chimeric WNV vaccine, and passive immunization with anti-JEV immune sera prevented viremia in hamsters challenged with JEV.

  3. 猪乙型脑炎疫苗的研究进展%Research Progress of Japanese Encephalitis Vaccine used for Swine

    Institute of Scientific and Technical Information of China (English)

    秦红刚; 肖敏; 李伟; 谢红玲; 漆世华; 温文生; 吴玉石

    2012-01-01

    Japanese encephalitis is a zoonotic infectious disease caused by a neurotropic arbovirus. Vaccine immunization is the primary means of control swine Japanese encephalitis. This reviewed focus on the latest research progress of conventional and novel Japanese encephalitis vaccine used for swine. This article provided references for the research of swine influenza vaccine%猪乙型脑炎是一种嗜神经性虫媒病毒引起的人兽共患传染病。疫苗的免疫接种是控制猪乙型脑炎发生的主要手段。阐述了猪乙型脑炎常规疫苗和新型疫苗的研究进展,为进一步研究猪乙型脑炎疫苗提供参考。

  4. Seroepidemiological Evidence for the Presence of Japanese Encephalitis Virus Infection in Ducks, Chickens, and Pigs, Bali-Indonesia

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    Anak Agung Ayu Mirah Adi

    2016-11-01

    Full Text Available Background: The presence of various animals, such as: ducks, chickens and pigs in households increases the potential risks of zoonosis from animal to human. One of the diseases is Japanese encephalitis (JE.  The seroepidemiological studies on the presence JE among animals especially those raised in household is very important for emerging and reemerging disease control program. Ducks, chickens and pigs have long been considered as carrier and even the amplifier hosts of Japanese encephalitis virus (JEV replication. The presence of the animal hosts and mosquitoes as vector could result in transmission of the JEV to humans. Methods: A seroepidemiological study of the presence of Japanese encephalitis virus (JEV was conducted by collecting sera and detecting the antibody against JEV in ducks, chickens and pigs in Bali. As pig is the amplifying animal of JEV, comparison JEV antibody between ducks reared in households with pig nearby and with no pig were also determined the presence of antibody against JEV was examined by using indirect enzyme-linked immunosorbent assay (ELISA.  The serum samples with over cut off value (COV of optical density were considered as those containing Ab against JEV. Results: Antibody against JEV was demonstrated in ducks (20.6%, chickens (36.7% and pigs (32.2% evaluated in this study. Moreover, there was no significant difference (p>0.05 in the prevalence of antibody against JEV in ducks kept closely with pigs compared to the antibody in the ducks reared without pigs around. Conclusion: This study convinced that antibody against JEV is found in ducks, chickens and pigs in Bali. Indicating that these animals was infected or previously infected by the virus.

  5. Isolation and genetic characteristics of human genotype 1 Japanese encephalitis virus, China, 2009.

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    Jiu-Song Zhang

    Full Text Available BACKGROUND: Several studies have shown that the predominant genotype of Chinese Japanese encephalitis virus (JEV is evolving from genotype 3 to genotype 1. However, in recent years, almost all genotype 1 isolates were from mosquitoes, and genotype 1 has been less associated with human disease than genotype 3. This study reports the isolation of human genotype 1 JEV and its genetic characteristics to provide additional insights into human JE pathogens that are currently circulating in China. METHODS AND RESULTS: In 2009, 31 cerebrospinal fluid samples were collected from patients living in Yunnan and Shanxi provinces and were used to inoculate Aedes albopictus C6/36 cells for virus isolation. The JEV strains were identified using immunofluorescent assays and the reverse transcription-polymerase chain reaction. Phylogenetic analyses based on the partial capsid/pre-membrane and full envelope (E sequences were performed using Clustalx 1.8 software. Three JEV isolates were obtained from a 4-year-old girl and a 2-year-old boy living in Yunnan and an 82-year-old woman in Shanxi. The boy had been immunized with one dose of JE live attenuated vaccine. New isolates were grouped into genotype 1. Amino acid sequence for the viral E protein indicated 95% to 100% identity with each other and with other JEV strains. When compared with a consensus sequence of E protein, two amino acid substitutions were found: Ser(E-123-Asn in the two Yunnan isolates and Lys(E-166-Arg in the Shanxi isolate. CONCLUSIONS: Our findings indicate that the genotype 1 of JEV is causing human infections in China. Our observation of a previously vaccinated boy developing JE from genotype 1 virus infection also calls for more detailed studies, both in vitro and in vivo neutralization tests as well as active surveillance, to examine the possibility of a lack of complete protection conferred by the live attenuated JE vaccine against genotype 1 virus.

  6. Multiple-Insecticide Resistance and Classic Gene Mutations to Japanese Encephalitis Vector Culex tritaeniorhynchus from China.

    Science.gov (United States)

    Wu, Zhi-Ming; Chu, Hong-Liang; Wang, Gang; Zhu, Xiao-Juan; Guo, Xiao-Xia; Zhang, Ying-Mei; Xing, Dan; Yan, Ting; Zhao, Ming-Hui; Dong, Yan-De; Li, Chun-Xiao; Zhao, Tong-Yan

    2016-06-01

    Widespread resistance of insect pests to insecticides has been widely reported in China and there is consequently an urgent need to adjust pest management strategies appropriately. This requires detailed information on the extent and causes of resistance. The aim of the present study was to investigate levels of resistance to 5 insecticides among 12 strains of Culex tritaeniorhynchus, a major vector of Japanese encephalitis in China. Resistance to deltamethrin, beta-cypermethrin, permethrin, dichlorvos, and propoxur were measured using larval bioassays. The allelic frequency of knockdown resistance (kdr) and acetylcholinesterase (AChE) mutations were determined in all strains. Larval bioassay results indicated that the field strains collected from different sites were resistant to deltamethrin, beta-cypermethrin, permethrin, dichlorvos, and propoxur, with resistance ratio values ranging from 1.70- to 71.98-fold, 7.83- to 43.07-fold, 3.54- to 40.03-fold, 291.85- to 530.89-fold, and 51.32- to 108.83-fold, respectively. A polymerase chain reaction amplification of specific alleles method for individual was developed to detect genotypes of the AChE gene mutation F455W in Cx. tritaeniorhynchus. The frequency of the AChE gene mutation F455W was 100.00% in all strains, making this mutation of no value as a marker of resistance to organophosphorous and carbamate pesticides in Cx. tritaeniorhynchus in China. The kdr allele was present in all strains at frequencies of 10.00-29.55%. Regression analysis indicated a significant correlation between kdr allele frequencies and levels of resistance to deltamethrin, beta-cypermethrin, and permethrin. These results highlight the need to monitor and map insecticide resistance in Cx. tritaeniorhynchus and to adjust pesticide use to minimize the development of resistance in these mosquitoes.

  7. RIG-I mediates innate immune response in mouse neurons following Japanese encephalitis virus infection.

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    Arshed Nazmi

    Full Text Available BACKGROUND: Neuroinflammation associated with Japanese encephalitis (JE is mainly due to the activation of glial cells with subsequent release of proinflammatory mediators from them. The recognition of viral RNA, in part, by the pattern recognition receptor retinoic acid-inducible gene I (RIG-I has been indicated to have a role in such processes. Even though neurons are also known to express this receptor, its role after JE virus (JEV infections is yet to be elucidated. METHODOLOGY/PRINCIPAL FINDINGS: Upon infecting murine neuroblastoma cells and primary cortical neurons with JEV the expression profile of key proinflammatory cyto/chemokines were analyzed by qRT-PCR and bead array, both before and after ablation of RIG-I. Immunoblotting was performed to evaluate the levels of key molecules downstream to RIG-I leading to production of proinflammatory mediators. Changes in the intracellular viral antigen expression were confirmed by intracellular staining and immunoblotting. JEV infection induced neuronal expression of IL-6, IL-12p70, MCP-1, IP-10 and TNF-α in a time-dependent manner, which showed significant reduction upon RIG-I ablation. Molecules downstream to RIG-I showed significant changes upon JEV-infection, that were modulated following RIG-I ablation. Ablation of RIG-I in neurons also increased their susceptibility to JEV. CONCLUSIONS/SIGNIFICANCE: In this study we propose that neurons are one of the potential sources of proinflammatory cyto/chemokines in JEV-infected brain that are produced via RIG-I dependent pathways. Ablation of RIG-I in neurons leads to increased viral load and reduced release of the cyto/chemokines.

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

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    Yan-Jang S Huang

    2016-10-01

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

  9. The Incidence of Japanese Encephalitis in Taiwan—A Population-Based Study

    Science.gov (United States)

    Hsu, Li-Ching; Chen, Yu-Ju; Hsu, Feng-Kuang; Huang, Jyh-Hsiung; Chang, Chi-Ming; Chou, Pesus; Lin, I-Feng; Chang, Feng-Yee

    2014-01-01

    Background A mass Japanese encephalitis (JE) vaccination program targeting children was launched in Taiwan in 1968, and the number of pediatric JE cases substantially decreased thereafter. The aim of this study was to elucidate the long-term trend of JE incidence, and to investigate the age-specific seroprevalence of JE-neutralizing antibodies. Methodology/Principal Findings A total of 2,948 laboratory-confirmed JE cases that occurred between 1966 and 2012 were analyzed using a mandatory notification system managed by the Centers for Disease Control, Taiwan. A total of 6,594 randomly-sampled serum specimens obtained in a nationwide population-based survey in 2002 were analyzed to estimate the seroprevalence of JE-neutralizing antibodies in the general population. The average annual JE incidence rate of the group aged 30 years and older was 0.167 cases per 100,000 people between 2001 and 2012, which was higher than the 0.052 cases per 100,000 people among those aged under 30 years. These seroepidemiological findings indicate that the cohort born between 1963 and 1975, who generally received two or three doses of the vaccine and were administered the last booster dose more than 20 years ago, exhibited the lowest positive rate of JE-neutralizing antibodies (54%). The highest and second highest antibody rates were observed, respectively, in the oldest unvaccinated cohort (86%) and in the youngest cohort born between 1981 and 1986, who received four doses 10–15 years ago (74%). Conclusion/Significance Over the past decade, the main age group of the confirmed JE cases in Taiwan shifted from young children to adults over 30 years of age. People who were born between 1963 and 1975 exhibited the lowest seroprevalence of JE-neutralizing antibodies. Thus, the key issue for JE control in Taiwan is to reduce adult JE cases through a cost-effective analysis of various immunization strategies. PMID:25058573

  10. Community knowledge and attitude towards Japanese encephalitis in Darrang, India: a cross-sectional study

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    Akram Ahmad

    2017-01-01

    Full Text Available Background: The prevalence of Japanese encephalitis (JE in Assam was exceptional in a global context in the year 2014. Darrang district is amongst the most affected districts that is hit by deadly JE virus in Assam. Therefore, we conducted this study to evaluate the knowledge and attitudes of the residents regarding JE at Darrang. Methods: A descriptive, cross-sectional study was performed for the period of 3 months from November 2014 to January 2015 in Darrang. Multistage stage sampling was done to select participants from the district. A pretested interviewer-administered questionnaire was used to collect data from the participants. Descriptive analysis and logistic regression tests were used to analyze the data. Results: A total of 396 participants responded to the questionnaire, thus giving the response rate of 51.5%. One-fourth of the participants exhibited a good knowledge of JE (24.7%. The majority of the participants incorrectly answered the questions relating to management (83.3% and prevention of JE (66.7%. Further, tertiary education and JE patient in family/relative were significantly associated with the knowledge of the participants (P < 0.001. A large proportion of the respondents exhibited positive attitudes towards JE (96.5%. Television was the major source of information of the participants regarding JE (29.2%. Conclusion: The findings of this study indicate a lack of knowledge regarding JE among the residents of Darrang. However, their attitudes towards JE were generally positive. Further studies on this topic need to be conducted throughout the state of Assam to identify and subsequently bridge the knowledge gaps among its residents.

  11. Japanese encephalitis virus induce immuno-competency in neural stem/progenitor cells.

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    Sulagna Das

    Full Text Available BACKGROUND: The low immunogenicity of neural stem/progenitor cells (NSPCs coupled with negligible expression of MHC antigens has popularized their use in transplantation medicine. However, in an inflammatory environment, the NSPCs express costimulatory molecules and MHC antigens, and also exhibit certain immunomodulatory functions. Since NSPCs are the cellular targets in a number of virus infections both during postnatal and adult stages, we wanted to investigate the immunological properties of these stem cells in response to viral pathogen. METHODOLOGY/PRINCIPAL FINDINGS: We utilized both in vivo mouse model and in vitro neurosphere model of Japanese encephalitis virus (JEV infection for the study. The NSPCs residing in the subventricular zone of the infected brains showed prominent expression of MHC-I and costimulatory molecules CD40, CD80, and CD86. Using Flow cytometry and fluorescence microscopy, we observed increased surface expression of co-stimulatory molecule and MHC class I antigen in NSPCs upon progressive JEV infection in vitro. Moreover, significant production of pro-inflammatory cyto/chemokines was detected in JEV infected NSPCs by Cytokine Bead Array analysis. Interestingly, NSPCs were capable of providing functional costimulation to allogenic T cells and JEV infection resulted in increased proliferation of allogenic T cells, as detected by Mixed Lymphocyte reaction and CFSE experiments. We also report IL-2 production by NSPCs upon JEV infection, which possibly provides mitogenic signals to T cells and trigger their proliferation. CONCLUSION/SIGNIFICANCE: The in vivo and in vitro findings clearly indicate the development of immunogenicity in NSPCs following progressive JEV infection, in our case, JEV infection. Following a neurotropic virus infection, NSPCs possibly behave as immunogenic cells and contribute to both the innate and adaptive immune axes. The newly discovered immunological properties of NSPCs may have implications in

  12. The spatial heterogeneity between Japanese encephalitis incidence distribution and environmental variables in Nepal.

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    Daniel E Impoinvil

    Full Text Available BACKGROUND: To identify potential environmental drivers of Japanese Encephalitis virus (JE transmission in Nepal, we conducted an ecological study to determine the spatial association between 2005 Nepal JE incidence, and climate, agricultural, and land-cover variables at district level. METHODS: District-level data on JE cases were examined using Local Indicators of Spatial Association (LISA analysis to identify spatial clusters from 2004 to 2008 and 2005 data was used to fit a spatial lag regression model with climate, agriculture and land-cover variables. RESULTS: Prior to 2006, there was a single large cluster of JE cases located in the Far-West and Mid-West terai regions of Nepal. After 2005, the distribution of JE cases in Nepal shifted with clusters found in the central hill areas. JE incidence during the 2005 epidemic had a stronger association with May mean monthly temperature and April mean monthly total precipitation compared to mean annual temperature and precipitation. A parsimonious spatial lag regression model revealed, 1 a significant negative relationship between JE incidence and April precipitation, 2 a significant positive relationship between JE incidence and percentage of irrigated land 3 a non-significant negative relationship between JE incidence and percentage of grassland cover, and 4 a unimodal non-significant relationship between JE Incidence and pig-to-human ratio. CONCLUSION: JE cases clustered in the terai prior to 2006 where it seemed to shift to the Kathmandu region in subsequent years. The spatial pattern of JE cases during the 2005 epidemic in Nepal was significantly associated with low precipitation and the percentage of irrigated land. Despite the availability of an effective vaccine, it is still important to understand environmental drivers of JEV transmission since the enzootic cycle of JEV transmission is not likely to be totally interrupted. Understanding the spatial dynamics of JE risk factors may be

  13. Japanese Encephalitis in Assam, India: Need to Increase Healthcare Workers' Understanding to Improve Health Care.

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    Akram Ahmad

    Full Text Available Japanese encephalitis (JE is a major cause of high morbidity and mortality in several states across India. However, in 2014, a sharp rise was observed in the number of cases of JE in north-eastern Assam state, and 51% of the total cases of JE in India were reported from the Assam in the same year. In this regard, a study was conducted to evaluate the knowledge and attitudes of healthcare workers in Darrang, a district of Assam highly affected by JE.A cross sectional study was conducted for 2 months among HCWs in the major district hospital of Darrang, Assam. A pre-tested, self-administered questionnaire was used to collect data from the participants. Convenience sampling approach was used to collect data from different departments of the hospitals. Descriptive and logistic regression analyses were used to express the results.The knowledge of HCWs regarding JE was poor with a mean knowledge score of 11.02±2.39 (out of 17, while their attitudes were positive with a mean attitudes score of 43.16± 2.47 (ranging from 13 to 52. Overall, 40.4% and 74.3% of participants demonstrated good knowledge and positive attitudes respectively. Cut-off score for good knowledge and positive attitudes toward JE was set as ≥12 and >40 respectively. Older participants (40-49 years and experienced workers (>10 years were significantly associated with good knowledge as compared to their referent group (p<0.05, while knowledge of nurses and other orderlies were significantly lower than physicians (p<0.01. Similar factors were associated with the positive attitudes of the participants with the exception of experience. Television was the major source of information regarding JE reported by HCWs (79%.Although the knowledge was not optimized, HCWs exhibited positive attitudes towards JE. Future research is required to design, implement and evaluate interventions to improve the knowledge of JE among HCWs.

  14. Genetic diversity of Japanese encephalitis virus isolates obtained from the Indonesian archipelago between 1974 and 1987.

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    Schuh, Amy J; Guzman, Hilda; Tesh, Robert B; Barrett, Alan D T

    2013-07-01

    Five genotypes (GI-V) of Japanese encephalitis virus (JEV) have been identified, all of which have distinct geographical distributions and epidemiologies. It is thought that JEV originated in the Indonesia-Malaysia region from an ancestral virus. From that ancestral virus GV diverged, followed by GIV, GIII, GII, and GI. Genotype IV appears to be confined to the Indonesia-Malaysia region, as GIV has been isolated in Indonesia from mosquitoes only, while GV has been isolated on three occasions only from a human in Malaysia and mosquitoes in China and South Korea. In contrast, GI-III viruses have been isolated throughout Asia and Australasia from a variety of hosts. Prior to this study only 13 JEV isolates collected from the Indonesian archipelago had been studied genetically. Therefore the sequences of the envelope (E) gene of 24 additional Indonesian JEV isolates, collected throughout the archipelago between 1974 and 1987, were determined and a series of molecular adaptation analyses were performed. Phylogenetic analysis indicated that over a 14-year time span three genotypes of JEV circulated throughout Indonesia, and a statistically significant association between the year of virus collection and genotype was revealed: isolates collected between 1974 and 1980 belonged to GII, isolates collected between 1980 and 1981 belonged to GIV, and isolates collected in 1987 belonged to GIII. Interestingly, three of the GII Indonesian isolates grouped with an isolate that was collected during the JE outbreak that occurred in Australia in 1995, two of the GIII Indonesian isolates were closely related to a Japanese isolate collected 40 years previously, and two Javanese GIV isolates possessed six amino acid substitutions within the E protein when compared to a previously sequenced GIV isolate collected in Flores. Several amino acids within the E protein of the Indonesian isolates were found to be under directional evolution and/or co-evolution. Conceivably, the tropical climate

  15. A novel immunochromatographic test applied to a serological survey of Japanese encephalitis virus on pig farms in Korea.

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    Go-Woon Cha

    Full Text Available Among vertebrate species, pigs are a major amplifying host of Japanese encephalitis virus (JEV and measuring their seroconversion is a reliable indicator of virus activity. Traditionally, the hemagglutination inhibition test has been used for serological testing in pigs; however, it has several limitations and, thus, a more efficient and reliable replacement test is required. In this study, we developed a new immunochromatographic test for detecting antibodies to JEV in pig serum within 15 min. Specifically, the domain III region of the JEV envelope protein was successfully expressed in soluble form and used for developing the immunochromatographic test. The test was then applied to the surveillance of Japanese encephalitis (JE in Korea. We found that our immunochromatographic test had good sensitivity (84.8% and specificity (97.7% when compared with an immunofluorescence assay used as a reference test. During the surveillance of JE in Korea in 2012, the new immunochromatographic test was used to test the sera of 1,926 slaughtered pigs from eight provinces, and 228 pigs (11.8% were found to be JEV-positive. Based on these results, we also produced an activity map of JEV, which marked the locations of pig farms in Korea that tested positive for the virus. Thus, the immunochromatographic test reported here provides a convenient and effective tool for real-time monitoring of JEV activity in pigs.

  16. Serological Prevalence Against Japanese Encephalitis Virus-Serocomplex Flaviviruses in Commensal and Field Rodents in South China.

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    Chen, Shao-Wei; Jiang, Li-Na; Zhong, Xue-Shan; Zheng, Xue-Yan; Ma, Shu-Juan; Xiong, Yi-Quan; Zhou, Jun-Hua; Li, Xing; Ke, Xue-Mei; Zhou, Wen; Chen, Qing

    2016-12-01

    Japanese encephalitis caused by Japanese encephalitis virus (JEV) is an endemic zoonotic disease of high public health importance in the Asian Pacific region. The aim of this study was to investigate the presence of JEV infection in commensal and field rodents in South China. RNA copies of JEV were detected in brain samples of rodents using real-time RT-PCR. Detection of serum against JEV-reactive antibodies was performed using indirect enzyme-linked immunosorbent assay and microneutralization test. In total, 198 rodents were collected from Guangzhou City and Xiamen City between November 2013 and May 2014. JEV RNA was not detected in 188 brain samples. Forty-four in 96 serum samples (45.8%) were positive for JEV-reactive IgG antibodies. The prevalence of neutralizing antibodies to against JEV-reactive in these serum samples was 61.5% (24/39), with titers ranging from 1:10 to 1:56. Rodents are not known to play a role in transmission of JEV in Asia, nor is there an evidence to support a role for rodents in transmission of other related flaviviruses in China. However, in the current study, we detected evidence of JEV-reactive antibodies in large numbers of Rattus norvegicus and Rattus losea Swinhoe. Further studies of rodents as potential hosts of JEV or other related flaviviruses are warranted.

  17. Biochemical characterization of a recombinant Japanese encephalitis virus RNA-dependent RNA polymerase

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    Kim Chan-Mi

    2007-07-01

    Full Text Available Abstract Background Japanese encephalitis virus (JEV NS5 is a viral nonstructural protein that carries both methyltransferase and RNA-dependent RNA polymerase (RdRp domains. It is a key component of the viral RNA replicase complex that presumably includes other viral nonstructural and cellular proteins. The biochemical properties of JEV NS5 have not been characterized due to the lack of a robust in vitro RdRp assay system, and the molecular mechanisms for the initiation of RNA synthesis by JEV NS5 remain to be elucidated. Results To characterize the biochemical properties of JEV RdRp, we expressed in Escherichia coli and purified an enzymatically active full-length recombinant JEV NS5 protein with a hexahistidine tag at the N-terminus. The purified NS5 protein, but not the mutant NS5 protein with an Ala substitution at the first Asp of the RdRp-conserved GDD motif, exhibited template- and primer-dependent RNA synthesis activity using a poly(A RNA template. The NS5 protein was able to use both plus- and minus-strand 3'-untranslated regions of the JEV genome as templates in the absence of a primer, with the latter RNA being a better template. Analysis of the RNA synthesis initiation site using the 3'-end 83 nucleotides of the JEV genome as a minimal RNA template revealed that the NS5 protein specifically initiates RNA synthesis from an internal site, U81, at the two nucleotides upstream of the 3'-end of the template. Conclusion As a first step toward the understanding of the molecular mechanisms for JEV RNA replication and ultimately for the in vitro reconstitution of viral RNA replicase complex, we for the first time established an in vitro JEV RdRp assay system with a functional full-length recombinant JEV NS5 protein and characterized the mechanisms of RNA synthesis from nonviral and viral RNA templates. The full-length recombinant JEV NS5 will be useful for the elucidation of the structure-function relationship of this enzyme and for the

  18. Antiviral and neuroprotective role of octaguanidinium dendrimer-conjugated morpholino oligomers in Japanese encephalitis.

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    Arshed Nazmi

    Full Text Available BACKGROUND: Japanese encephalitis (JE, caused by a mosquito-borne flavivirus, is endemic to the entire south-east Asian and adjoining regions. Currently no therapeutic interventions are available for JE, thereby making it one of the most dreaded encephalitides in the world. An effective way to counter the virus would be to inhibit viral replication by using anti-sense molecules directed against the viral genome. Octaguanidinium dendrimer-conjugated Morpholino (or Vivo-Morpholino are uncharged anti-sense oligomers that can enter cells of living organisms by endocytosis and subsequently escape from endosomes into the cytosol/nuclear compartment of cells. We hypothesize that Vivo-Morpholinos generated against specific regions of 3' or 5' untranslated regions of JEV genome, when administered in an experimental model of JE, will have significant antiviral and neuroprotective effect. METHODOLOGY/PRINCIPAL FINDINGS: Mice were infected with JEV (GP78 strain followed by intraperitoneal administration of Morpholinos (5 mg/kg body weight daily for up to five treatments. Survivability of the animals was monitored for 15 days (or until death following which they were sacrificed and their brains were processed either for immunohistochemical staining or protein extraction. Plaque assay and immunoblot analysis performed from brain homogenates showed reduced viral load and viral protein expression, resulting in greater survival of infected animals. Neuroprotective effect was observed by thionin staining of brain sections. Cytokine bead array showed reduction in the levels of proinflammatory cytokines in brain following Morpholino treatment, which were elevated after infection. This corresponded to reduced microglial activation in brain. Oxidative stress was reduced and certain stress-related signaling molecules were found to be positively modulated following Morpholino treatment. In vitro studies also showed that there was decrease in infective viral particle

  19. Anti-Japanese-encephalitis-viral effects of kaempferol and daidzin and their RNA-binding characteristics.

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    Ting Zhang

    Full Text Available BACKGROUND: New therapeutic tools and molecular targets are needed for treatment of Japanese encephalitis virus (JEV infections. JEV requires an α-1 translational frameshift to synthesize the NS1' protein required for viral neuroinvasiveness. Several flavonoids have been shown to possess antiviral activity in vitro against a wide spectrum of viruses. To date, the antiviral activities of flavonol kaempferol (Kae and isoflavonoid daidzin (Dai against JEV have not been described. METHODOLOGY/PRINCIPAL FINDINGS: The 50% cytotoxic concentration (CC(50 and 50% effective concentration (EC(50 against JEV were investigated in BHK21 cells by MTS reduction. Activity against viral genomic RNA and proteins was measured by real-time RT-PCR and western blotting. The frameshift site RNA-binding characterization was also determined by electrospray ionization mass spectrometry, isothermal titration calorimetry and autodocking analysis. EC(50 values of Kae and Dai were 12.6 and 25.9 µM against JEV in cells pretreated before infection, whereas in cells infected before treatment, EC(50 was 21.5 and 40.4 µM, respectively. Kae exhibited more potent activity against JEV and RNA binding in cells following internalization through direct inhibition of viral replication and protein expression, indicating that its antiviral activity was principally due to direct virucidal effects. The JEV frameshift site RNA (fsRNA was selected as a target for assaying Kae and Dai. ITC of fsRNA revealed an apparent K(b value for Kae that was nine fold stronger than that for Dai. This binding was confirmed and localized to the RNA using ESI-MS and autodock analysis. Kae could form non-covalent complexes with fsRNA more easily than Dai could. CONCLUSIONS/SIGNIFICANCE: Kae demonstrates more potent antiviral activity against JEV than does Dai. The mode of action of Kae as an anti-JEV agent seems to be related to its ability to inactivate virus by binding with JEV fsRNA.

  20. A curious coincidence: mosquito biodiversity and the limits of the Japanese encephalitis virus in Australasia

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    Russell Richard C

    2007-06-01

    Full Text Available Abstract Background The mosquito Culex annulirostris Skuse (Diptera: Culicidae is the major vector of endemic arboviruses in Australia and is also responsible for the establishment of the Japanese encephalitis virus (JEV in southern Papua New Guinea (PNG as well as its incursions into northern Australia. Papua New Guinea and mainland Australia are separated by a small stretch of water, the Torres Strait, and its islands. While there has been regular JEV activity on these islands, JEV has not established on mainland Australia despite an abundance of Cx. annulirostris and porcine amplifying hosts. Despite the public health significance of this mosquito and the fact that its adults show overlapping morphology with close relative Cx. palpalis Taylor, its evolution and genetic structure remain undetermined. We address a hypothesis that there is significant genetic diversity in Cx. annulirostris and that the identification of this diversity will shed light on the paradox that JEV can cycle on an island 70 km from mainland Australia while not establishing in Australia itself. Results We sequenced 538 bp of the mitochondrial DNA cytochrome oxidase I gene from 273 individuals collected from 43 localities in Australia and the southwest Pacific region to describe the phylogeography of Cx. annulirostris and its sister species Cx. palpalis. Maximum Likelihood and Bayesian analyses reveal supporting evidence for multiple divergent lineages that display geographic restriction. Culex palpalis contained three divergent lineages geographically restricted to southern Australia, northern Australia and Papua New Guinea (PNG. Culex annulirostris contained five geographically restricted divergent lineages, with one lineage restricted to the Solomon Islands and two identified mainly within Australia while two other lineages showed distributions in PNG and the Torres Strait Islands with a southern limit at the top of Australia's Cape York Peninsula. Conclusion The

  1. Single rapid TaqMan fluorogenic probe based PCR assay that detects all four dengue serotypes.

    Science.gov (United States)

    Warrilow, David; Northill, Judith A; Pyke, Alyssa; Smith, Greg A

    2002-04-01

    Public health laboratories require rapid diagnosis of dengue outbreaks for application of measures such as vector control. We have developed a rapid single fluorogenic probe-based polymerase chain reaction assay for the detection of all four dengue serotypes (FUDRT-PCR). The method employs primers and probe that are complementary to the evolutionarily conserved 3' untranslated region of the dengue genome. The assay detected viral RNA of strains of all four dengue serotypes but not of the flaviviruses Japanese encephalitis virus, Murray Valley encephalitis virus, Kunjin, Stratford, West Nile, Alfuy or Yellow fever. When compared to an existing nested-PCR assay for the detection of dengue on clinical samples, FUDRT-PCR detected dengue 1 (100%, n=14), dengue 2 (85%, n=13), dengue 3 (64%, n=14) and dengue 4 (100%, n=3) with the indicated sensitivities. FUDRT-PCR enables diagnosis of acute dengue infection in four hours from sample receipt. In addition, a single-test procedure should result in a reduction in the number of tests performed with considerable cost savings for diagnostic laboratories.

  2. Detection and differentiation of Japanese encephalitis virus genotype I and genotype III by reverse transcription loop-mediated isothermal amplification combined with restriction fragment length polymorphism.

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    Zhang, Liang; Cao, Sanjie; Wu, Rui; Zhu, Shuquan; Liu, Hanyang; Yuan, Lei; Shi, Shuangyan; Zhang, Dan; Huang, Xiaobo; Wen, Xintian; Wen, Yiping; Yan, Qigui; Huang, Yong; Ma, Xiaoping

    2015-04-01

    Japanese encephalitis (JE), which is a mosquito-borne arboviral infection, is the leading cause of viral encephalitis in Asian countries. The causative agent of JE is Japanese encephalitis virus (JEV), in which the predominant genotype has changed from genotype III (G III) to genotype I (G I). However, a method for the rapid differentiation between JEV G I and G III remains unavailable. This study aimed to establish a rapid JEV genotyping method using reverse transcription loop-mediated isothermal amplification (RT-LAMP). An Spe I site, which was located in the target sequence (C gene) of JEV G III strains but not in JEV G I strains, was selected as the RT-LAMP target. After testing 64 specimens, results showed that RT-LAMP can detect and differentiate JEV G I and G III specifically. Thus, a novel RT-LAMP system for the rapid detection and differentiation of JEV G I and G III was developed successfully.

  3. The Chemokine Receptor CCR5, a Therapeutic Target for HIV/AIDS Antagonists, Is Critical for Recovery in a Mouse Model of Japanese Encephalitis

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    Larena, Maximilian; Regner, Matthias; Lobigs, Mario

    2012-01-01

    Japanese encephalitis is a severe central nervous system (CNS) inflammatory disease caused by the mosquito-borne flavivirus, Japanese encephalitis virus (JEV). In the current study we have investigated the immune responses against JEV in mice lacking expression of the chemokine receptor CCR5, which functions in activation and chemotaxis of leukocytes during infection. We show that CCR5 serves as a host antiviral factor against Japanese encephalitis, with CCR5 deficiency markedly increasing mortality, and viral burden in the CNS. Humoral immune responses, which are essential in recovery from JEV infection, were of similar magnitude in CCR5 sufficient and deficient mice. However, absence of CCR5 resulted in a multifaceted deficiency of cellular immune responses characterized by reduced natural killer and CD8+ T cell activity, low splenic cellularity, and impaired trafficking of leukocytes to the brain. Interestingly, adoptive transfer of immune spleen cells, depleted of B lymphocytes, increased resistance of CCR5-deficient recipient mice against JEV regardless of whether the cells were obtained from CCR5-deficient or wild-type donor mice, and only when transferred at one but not at three days post-challenge. This result is consistent with a mechanism by which CCR5 expression enhances lymphocyte activation and thereby promotes host survival in Japanese encephalitis. PMID:23028638

  4. Cloning and application of recombinant dengue virus prM-M protein for serodiagnosis of dengue virus infection.

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    Wichit, Sineewanlaya; Yongpradoem, Hatairat; Surasombatpattana, Pornapat; Leaungwuttiwong, Pornsawan; Kalambaheti, Thareerat; Jampangern, Wipawee; Jittmittraphap, Akanitt

    2013-03-01

    We studied the use of the precursor to the M structural protein (prM) found only on the surface of mature dengue virus as a target protein to detect dengue virus infection. Recombinant D2-16681 prM-M protein was constructed and tested for immunogenicity with dengue and Japanese encephalitis patient sera by Western blot analysis and indirect ELISA. The sensitivity and specificity of indirect ELISA were 48.1 and 85.5%, respectively, and Western blot assay were 23.1 and 98.7%, respectively, for detection of dengue virus. Although the sensitivity of the indirect ELISA is low, the indirect ELISA using recombinant D2-16681 prM-M proteins as antigen may be used for early detection of dengue virus infection.

  5. mosGCTL-7, a C-Type Lectin Protein, Mediates Japanese Encephalitis Virus Infection in Mosquitoes.

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    Liu, Ke; Qian, Yingjuan; Jung, Yong-Sam; Zhou, Bin; Cao, Ruibing; Shen, Ting; Shao, Donghua; Wei, Jianchao; Ma, Zhiyong; Chen, Puyan; Zhu, Huaimin; Qiu, Yafeng

    2017-05-15

    Japanese encephalitis virus (JEV) is an arthropod-borne flavivirus prevalent in Asia and the Western Pacific and is the leading cause of viral encephalitis. JEV is maintained in a transmission cycle between mosquitoes and vertebrate hosts, but the molecular mechanisms by which the mosquito vector participates in transmission are unclear. We investigated the expression of all C-type lectins during JEV infection in Aedes aegypti The C-type lectin mosquito galactose-specific C-type lectin 7 (mosGCTL-7) (VectorBase accession no. AAEL002524) was significantly upregulated by JEV infection and facilitated infection in vivo and in vitro mosGCTL-7 bound to the N-glycan at N154 on the JEV envelope protein. This recognition of viral N-glycan by mosGCTL-7 is required for JEV infection, and we found that this interaction was Ca(2+) dependent. After mosGCTL-7 bound to the glycan, mosPTP-1 bound to mosGCTL-7, promoting JEV entry. The viral burden in vivo and in vitro was significantly decreased by mosPTP-1 double-stranded RNA (dsRNA) treatment, and infection was abolished by anti-mosGCTL-7 antibodies. Our results indicate that the mosGCTL-7/mosPTP-1 pathway plays a key role in JEV infection in mosquitoes. An improved understanding of the mechanisms underlying flavivirus infection in mosquitoes will provide further opportunities for developing new strategies to control viral dissemination in nature.IMPORTANCE Japanese encephalitis virus is a mosquito-borne flavivirus and is the primary cause of viral encephalitis in the Asia-Pacific region. Twenty-four countries in the WHO Southeast Asia and Western Pacific regions have endemic JEV transmission, which exposes >3 billion people to the risks of infection, although JEV primarily affects children. C-type lectins are host factors that play a role in flavivirus infection in humans, swine, and other mammals. In this study, we investigated C-type lectin functions in JEV-infected Aedes aegypti and Culex pipiens pallens mosquitoes and

  6. Comparing the immunogenicity and safety of 3 Japanese encephalitis vaccines in Asia-Pacific area: A systematic review and meta-analysis.

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    Wang, Shi-Yuan; Cheng, Xiao-Hua; Li, Jing-Xin; Li, Xi-Yan; Zhu, Feng-Cai; Liu, Pei

    2015-01-01

    Japanese encephalitis virus (JEV), a leading cause of Japanese encephalitis (JE) in children and adults, is a major public health problem in Asian countries. This study reports a meta-analysis of the immunogenicity and safety of vaccines used to protect infants or children from JE. Three types of JE vaccine were examined, namely, Japanese encephalitis live-attenuated vaccine (JEV-L), Japanese encephalitis inactivated vaccine (Vero cell) (JEV-I(Vero)), and Japanese encephalitis inactivated vaccine (primary hamster kidney cell) (JEV-I(PHK)). These vaccines are used to induce fundamental immunity against JE; however, few studies have compared their immunogenicity and safety in infants and young children less than 2 years of age. Data were obtained by searching 5 databases: Web of Science, PubMed, China National Knowledge Infrastructure, the China Wanfang database, and the Cochrane database. Fifteen articles were identified and scored using the Jadad score for inclusion in the meta-analysis. Random effect models were used to calculate the pooled seroconversion rate and adverse reaction rate when tests for heterogeneity were significant. The results showed that the pooled seroconversion rate for JEV-I(PHK) (62.23%) was lower than that for JEV-I(Vero) (86.49%) and JEV-L (83.52%), and that the pooled adverse reaction rate for JEV-L (18.09%) was higher than that for JEV-I(PHK) (10.08%) and JEV-I(Vero) (12.49%). The pooled relative risk was then calculated to compare the seroconversion and adverse reaction rates. The results showed that JEV-I(Vero) and JEV-L were more suitable than JEV-I(PHK) for inducing fundamental immunity to JE in infants and children less than 2 years of age.

  7. Recombinant nucleocapsid-like particles from dengue-2 virus induce protective CD4+ and CD8+ cells against viral encephalitis in mice.

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    Gil, Lázaro; López, Carlos; Lazo, Laura; Valdés, Iris; Marcos, Ernesto; Alonso, Ruby; Gambe, Ailyn; Martín, Jorge; Romero, Yaremis; Guzmán, María G; Guillén, Gerardo; Hermida, Lisset

    2009-10-01

    Virus-like particles are a highly effective type of subunit vaccine that mimics the overall structure of virus particles without containing infectious genetic material. In this work, a particulate form of the recombinant capsid protein from dengue-2 was evaluated in mice to determine the level of protection against viral challenge and to measure the antigen-induced cell-mediated immunity (CMI). The nucleocapsid-like particles (NLPs) adjuvanted with alum did not induce antiviral antibodies. However, splenocytes from the immunized animals secreted high levels of IFN-gamma upon virus stimulation, and a significant protection rate was achieved after challenge with lethal dengue-2 virus. Finally, both IFN-gamma secretion and protection against viral encephalitis were demonstrated to be dependent on CD4(+) and CD8(+) cells. This study provides new evidences regarding the protective role of the CMI in the mouse model without the induction of neutralizing antibodies. Further studies in non-human primates or humanized mice should be carried out to elucidate the usefulness of the NLPs as a potential vaccine candidate against dengue disease.

  8. A heterologous DNA prime-Venezuelan equine encephalitis virus replicon particle boost dengue vaccine regimen affords complete protection from virus challenge in cynomolgus macaques.

    Science.gov (United States)

    Chen, Lan; Ewing, Dan; Subramanian, Hemavathy; Block, Karla; Rayner, Jonathan; Alterson, Kimberly D; Sedegah, Martha; Hayes, Curtis; Porter, Kevin; Raviprakash, Kanakatte

    2007-11-01

    A candidate vaccine (D1ME-VRP) expressing dengue virus type 1 premembrane and envelope proteins in a Venezuelan equine encephalitis (VEE) virus replicon particle (VRP) system was constructed and tested in conjunction with a plasmid DNA vaccine (D1ME-DNA) expressing identical dengue virus sequences. Cynomolgus macaques were vaccinated with three doses of DNA (DDD), three doses of VRP (VVV group), or a heterologous DNA prime-VRP boost regimen (DDV) using two doses of DNA vaccine and a third dose of VRP vaccine. Four weeks after the final immunization, the DDV group produced the highest dengue virus type 1-specific immunoglobulin G antibody responses and virus-neutralizing antibody titers. Moderate T-cell responses were demonstrated only in DDD- and DDV-vaccinated animals. When vaccinated animals were challenged with live virus, all vaccination regimens showed significant protection from viremia. DDV-immunized animals were completely protected from viremia (mean time of viremia = 0 days), whereas DDD- and VVV-vaccinated animals had mean times of viremia of 0.66 and 0.75 day, respectively, compared to 6.33 days for the control group of animals.

  9. Analysis of Dengue Virus Enhancing Epitopes Using Peptide Antigens Derived from the Envelope Glycoprotein Gene Sequence

    Science.gov (United States)

    1990-11-27

    WE. 1990. Development of dengue and Japanese encephalitis Vaccines . J Infect Dis 162:577-83. 2. Brandt WE, McCown JM, Gentry MK, and Russell PK. i982...7. 19. Roehrig JT, Johnson AJ, Hunt AR, Bolin RA, •d Chu MC. 1990. Antibodies to dengue 2 Jamaica E-glycopr tein synthetic peptides identify antigenic...AD________ AD-A230 976 ARMY PROJECT NO: 89PP9961 TITLE: ANALYSIS OF DENGUE VIRUS ENHANCING EPITOPES USING PEPTIDE ANTIGENS DERIVED FROM THE ENVELOPE

  10. Safety and immunogenicity of a delta inulin-adjuvanted inactivated Japanese encephalitis virus vaccine in pregnant mares and foals.

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    Bielefeldt-Ohmann, Helle; Prow, Natalie A; Wang, Wenqi; Tan, Cindy S E; Coyle, Mitchell; Douma, Alysha; Hobson-Peters, Jody; Kidd, Lisa; Hall, Roy A; Petrovsky, Nikolai

    2014-12-17

    In 2011, following severe flooding in Eastern Australia, an unprecedented epidemic of equine encephalitis occurred in South-Eastern Australia, caused by Murray Valley encephalitis virus (MVEV) and a new variant strain of Kunjin virus, a subtype of West Nile virus (WNVKUN). This prompted us to assess whether a delta inulin-adjuvanted, inactivated cell culture-derived Japanese encephalitis virus (JEV) vaccine (JE-ADVAX™) could be used in horses, including pregnant mares and foals, to not only induce immunity to JEV, but also elicit cross-protective antibodies against MVEV and WNVKUN. Foals, 74-152 days old, received two injections of JE-ADVAX™. The vaccine was safe and well-tolerated and induced a strong JEV-neutralizing antibody response in all foals. MVEV and WNVKUN antibody cross-reactivity was seen in 33% and 42% of the immunized foals, respectively. JE-ADVAX™ was also safe and well-tolerated in pregnant mares and induced high JEV-neutralizing titers. The neutralizing activity was passively transferred to their foals via colostrum. Foals that acquired passive immunity to JEV via maternal antibodies then were immunized with JE-ADVAX™ at 36-83 days of age, showed evidence of maternal antibody interference with low peak antibody titers post-immunization when compared to immunized foals of JEV-naïve dams. Nevertheless, when given a single JE-ADVAX™ booster immunization as yearlings, these animals developed a rapid and robust JEV-neutralizing antibody response, indicating that they were successfully primed to JEV when immunized as foals, despite the presence of maternal antibodies. Overall, JE-ADVAX™ appears safe and well-tolerated in pregnant mares and young foals and induces protective levels of JEV neutralizing antibodies with partial cross-neutralization of MVEV and WNVKUN.

  11. Capsid, membrane and NS3 are the major viral proteins involved in autophagy induced by Japanese encephalitis virus.

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    Wang, Xiujin; Hou, Lei; Du, Jige; Zhou, Lei; Ge, Xinna; Guo, Xin; Yang, Hanchun

    2015-08-05

    Japanese encephalitis virus (JEV) is an important zoonotic pathogen causing viral encephalitis in human and reproductive failure in pigs. In the present study, we first examined the autophagy induced by JEV infection in host cells, and then analyzed the JEV proteins involving in autophagy induction, and further investigated the relationship between viral protein and immunity-related GTPases M (IRGM). Our results showed that JEV infection could induce autophagy in host cells and autophagy promoted the replication of JEV in vitro; the cells transfected with individual plasmid that was expressing C, M and NS3 had a significantly higher conversion of LC3-I/II, and enhanced LC3 signals with the fluorescence punctuates accumulation which was completely co-localized with LC3 and increased number of autophagosomes-like vesicles, suggesting that C, M and NS3 are the major viral proteins involving in autophagy induction upon JEV infection; the virus titer in the cells treated by the siRNA specific for IRGM had a significant decrease, and the NS3 signals in the cells transfected with the plasmid that was expressing NS3 were completely co-localized with the IRGM signals, suggesting that the NS3 of JEV could target IRGM which may play a role in the replication of JEV. Our findings help to understand the role of autophagy in JEV and other flaviviruses infections.

  12. Heat shock protein 70 is associated with replicase complex of Japanese encephalitis virus and positively regulates viral genome replication.

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    Jing Ye

    Full Text Available Japanese encephalitis virus (JEV is a mosquito-borne flavivirus that causes the most prevalent viral encephalitis in Asia. The NS5 protein of JEV is a key component of the viral replicase complex, which plays a crucial role in viral pathogenesis. In this study, tandem affinity purification (TAP followed by mass spectrometry analysis was performed to identify novel host proteins that interact with NS5. Heat shock protein 70 (Hsp70, eukaryotic elongation factor 1-alpha (eEF-1α and ras-related nuclear protein (Ran were demonstrated to interact with NS5. In addition to NS5, Hsp70 was also found to interact with NS3 which is another important member of the replicase complex. It was observed that the cytoplasmic Hsp70 partially colocalizes with the components of viral replicase complex including NS3, NS5 and viral dsRNA during JEV infection. Knockdown of Hsp70 resulted in a significantly reduced JEV genome replication. Further analysis reveals that Hsp70 enhances the stability of viral proteins in JEV replicase complex. These results suggest an important role for Hsp70 in regulating JEV replication, which provides a potential target for the development of anti-JEV therapies.

  13. E3 Ubiquitin Ligase Nedd4 Promotes Japanese Encephalitis Virus Replication by Suppressing Autophagy in Human Neuroblastoma Cells

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    Xu, Qingqiang; Zhu, Naiwei; Chen, Shenglin; Zhao, Ping; Ren, Hao; Zhu, Shiying; Tang, Hailin; Zhu, Yongzhe; Qi, Zhongtian

    2017-01-01

    Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus that causes the most prevalent viral encephalitis in Asia. Since JEV is a neurotropic virus, it is important to identify key molecules that mediate JEV infection in neuronal cells and to investigate their underlying mechanisms. In this study, the critical role of Nedd4, an E3 ubiquitin ligase that is highly expressed in the central nervous system, was examined in JEV propagation. In SK-N-SH neuroblastoma cells, Nedd4 was up-regulated in response to JEV infection. Moreover, down-regulation of Nedd4 resulted in a significant decrease in JEV replication without alterations in virus attachment and internalization or in JEV pseudotyped virus infection, suggesting that Nedd4 participates in the replication but not in the entry stage of JEV infection. Further functional analysis showed that Nedd4 attenuated JEV-induced autophagy, which negatively regulates virus replication during infection. These results suggest that Nedd4 facilitates the replication of JEV by suppressing virus-induced autophagy. Taken together, our results indicate that Nedd4 plays a crucial role in JEV infection of neuronal cells, which provides a potential target for the development of novel treatment to combat JEV infection. PMID:28349961

  14. Recombinant Measles AIK-C Vaccine Strain Expressing the prM-E Antigen of Japanese Encephalitis Virus.

    Science.gov (United States)

    Higuchi, Akira; Toriniwa, Hiroko; Komiya, Tomoyoshi; Nakayama, Tetsuo

    2016-01-01

    An inactivated Japanese encephalitis virus (JEV) vaccine, which induces neutralizing antibodies, has been used for many years in Japan. In the present study, the JEV prM-E protein gene was cloned, inserted at the P/M junction of measles AIK-C cDNA, and an infectious virus was recovered. The JEV E protein was expressed in B95a cells infected with the recombinant virus. Cotton rats were inoculated with recombinant virus. Measles PA antibodies were detected three weeks after immunization. Neutralizing antibodies against JEV developed one week after inoculation, and EIA antibodies were detected three weeks after immunization. The measles AIK-C-based recombinant virus simultaneously induced measles and JEV immune responses, and may be a candidate for infant vaccines. Therefore, the present strategy of recombinant viruses based on a measles vaccine vector would be applicable to the platform for vaccine development.

  15. Griffithsin binds to the glycosylated proteins (E and prM) of Japanese encephalitis virus and inhibit its infection.

    Science.gov (United States)

    Ishag, Hassan Z A; Li, Chen; Wang, Fengjuan; Mao, Xiang

    2016-04-02

    Griffithsin (GRFT) is a broad-spectrum antiviral protein against several glycosylated viruses. In our previous publication, we have shown that GRFT exerted antiviral activity against Japanese encephalitis virus (JEV) infection. Herein, we further elucidated the mechanism by which GRFT inhibits JEV infection in BHK-21 cells. In vitro experiments using Pull-down assay and Co-immunoprecipitation (CO-IP) assay showed that GRFT binds to the JEV glycosylated viral proteins, specifically the enveloped (E) and premature (prM) glycoproteins. The binding of GRFT to the JEV was competitively inhibited by increasing concentrations of mannose; in turns abolished anti-JEV activity of GRFT. We suggested that, the binding of GRFT to the glycosylated viral proteins may contribute to its anti-JEV activity. Collectively, our data indicated a possible mechanism by which GRFT exerted its anti-JEV activity. This observation suggests GRFT's potentials in the development of therapeutics against JEV or other flavivirus infection.

  16. Seroprevalence of Japanese encephalitis virus using competitive enzyme linked immunosorbent assay (C-ELISA in pigs in East Sumba, Indonesia

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    Annytha Detha

    2015-12-01

    Full Text Available Japanese Encephalitis (JE, a vector-borne zoonotic viral disease, is mostly prevalent in Asian countries. The objective of this study was to investigate the occurence of JE virus (JEV among pigs in East Sumba, Indonesia. Blood samples (n=52 were randomly collected from 52 apparantly healthy pigs where pig population was high in East Sumba. The samples were subjected for seroprevalence study for the presence of antibodies against JEV using competitive enzyme linked immunosorbent assay (C-ELISA. Results showed that 53% (n=28/52 blood samples from the pigs contained antibodies against JEV. This finding is suggestive that the JEV is circulating among pig population in East Sumba, Indonesia. The data may help in designing control strategies of the JEV in the East Sumba, Indonesia.

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

    Science.gov (United States)

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

    2013-01-01

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

  18. Beneficial role of a nonpathogenic orbi-like virus: studies on the interfering effect of M14 virus in mice and mosquitoes infected with Japanese encephalitis virus.

    Science.gov (United States)

    Huang, C H; Liang, H C; Jia, F L

    1985-01-01

    M14 virus, isolated from Culex tritaeniorhynchus mosquitoes collected in a Beijing suburb, was identified as a noncytopathogenic orbi-like virus. It was found to interfere with the growth of Japanese encephalitis (JE) virus, a mosquito-borne virus which infects humans, pigs, and horses in much of Asia, including China. JE virus is transmitted by C. tritaeniorhynchus mosquitoes and causes encephalitis in humans and horses and abortion in pigs. Because it had potential as an interfering agent for the biological control of JE, the M14 virus was characterized and its interfering effect was studied in mice and in C. tritaeniorhynchus mosquitoes.

  19. THE GROWTH OF JAPANESE AND WEST NILE ENCEPHALITIS VIRUSES IN TISSUE CULTURES,

    Science.gov (United States)

    extinguishing it with a homologous immune serum. In the HeLa cells a specific cytopathogenic effect was registered after six cultural passages of the strain R...1. The cytopathogenic effect was retained in subinoculation. The West Nile encephalitis virus induced a cytopathogenic effect in the HeLa cells from

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

    Science.gov (United States)

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

    2015-12-10

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

  1. Cross-protection elicited by primary and booster vaccinations against Japanese encephalitis: a two-year follow-up study.

    Science.gov (United States)

    Erra, Elina O; Askling, Helena Hervius; Yoksan, Sutee; Rombo, Lars; Riutta, Jukka; Vene, Sirkka; Lindquist, Lars; Vapalahti, Olli; Kantele, Anu

    2013-12-17

    The inactivated Vero cell-derived vaccine (JE-VC, IXIARO) has replaced the traditional mouse brain-derived preparations (JE-MB) in travelers' vaccinations against Japanese encephalitis. We showed recently that a single JE-VC dose efficiently boosts immunity in JE-MB-primed vaccinees, and that JE-VC elicits cross-protective immunity against non-vaccine genotypes, including the emerging genotype I. While these studies only provided short-term data, the present investigation evaluates the longevity of seroprotection in the same volunteers. The study comprised 48 travelers who had received (1) JE-VC primary series, (2) JE-MB primary series followed by a single JE-VC booster dose, or (3) JE-MB primary series and a single JE-MB booster dose. Serum samples were collected two years after the last vaccine dose, and evaluated with the plaque-reduction neutralization test against seven Japanese encephalitis virus strains representing genotypes I-IV. PRNT50 titers ≥ 10 were considered protective. Two years after the primary series with JE-VC, 87-93% of the vaccinees proved to be cross-protected against test strains representing genotypes II-IV and 73% against those of genotype I. After a single homologous or heterologous booster dose to JE-MB-primed subjects, the two-year seroprotection rates against genotype I-IV strains were 89-100%. After JE-VC primary series, seroprotection appeared to wane first against genotype I. The first booster should not be delayed beyond two years. In JE-MB-primed subjects, a single JE-VC booster provided cross-protective immunity against genotype I-IV strains in almost all vaccinees, suggesting an interval of two years or even longer for the second booster. These data further support the use of a single JE-VC dose for boosting JE-MB immunity. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Sampling Design Influences the Observed Dominance of Culex tritaeniorhynchus: Considerations for Future Studies of Japanese Encephalitis Virus Transmission.

    Science.gov (United States)

    Lord, Jennifer S; Al-Amin, Hasan Mohammad; Chakma, Sumit; Alam, Mohammad Shafiul; Gurley, Emily S; Pulliam, Juliet R C

    2016-01-01

    Mosquito sampling during Japanese encephalitis virus (JEV)-associated studies, particularly in India, has usually been conducted via aspirators or light traps to catch mosquitoes around cattle, which are dead-end hosts for JEV. High numbers of Culex tritaeniorhynchus, relative to other species, have often been caught during these studies. Less frequently, studies have involved sampling outdoor resting mosquitoes. We aimed to compare the relative abundance of mosquito species between these two previously used mosquito sampling methods. From September to December 2013 entomological surveys were undertaken in eight villages in a Japanese encephalitis (JE) endemic area of Bangladesh. Light traps were used to collect active mosquitoes in households, and resting boxes and a Bina Pani Das hop cage were used near oviposition sites to collect resting mosquitoes. Numbers of humans and domestic animals present in households where light traps were set were recorded. In five villages Cx. tritaeniorhynchus was more likely to be selected from light trap samples near hosts than resting collection samples near oviposition sites, according to log odds ratio tests. The opposite was true for Cx. pseudovishnui and Armigeres subalbatus, which can also transmit JEV. Culex tritaeniorhynchus constituted 59% of the mosquitoes sampled from households with cattle, 28% from households without cattle and 17% in resting collections. In contrast Cx. pseudovishnui constituted 5.4% of the sample from households with cattle, 16% from households with no cattle and 27% from resting collections, while Ar. subalbatus constituted 0.15%, 0.38%, and 8.4% of these samples respectively. These observations may be due to differences in timing of biting activity, host preference and host-seeking strategy rather than differences in population density. We suggest that future studies aiming to implicate vector species in transmission of JEV should consider focusing catches around hosts able to transmit JEV.

  3. MicroRNA-19b-3p Modulates Japanese Encephalitis Virus-Mediated Inflammation via Targeting RNF11.

    Science.gov (United States)

    Ashraf, Usama; Zhu, Bibo; Ye, Jing; Wan, Shengfeng; Nie, Yanru; Chen, Zheng; Cui, Min; Wang, Chong; Duan, Xiaodong; Zhang, Hao; Chen, Huanchun; Cao, Shengbo

    2016-05-01

    Japanese encephalitis virus (JEV) can invade the central nervous system and consequently induce neuroinflammation, which is characterized by profound neuronal cell damage accompanied by astrogliosis and microgliosis. Albeit microRNAs (miRNAs) have emerged as major regulatory noncoding RNAs with profound effects on inflammatory response, it is unknown how astrocytic miRNAs regulate JEV-induced inflammation. Here, we found the involvement of miR-19b-3p in regulating the JEV-induced inflammatory responsein vitroandin vivo The data demonstrated that miR-19b-3p is upregulated in cultured cells and mouse brain tissues during JEV infection. Overexpression of miR-19b-3p led to increased production of inflammatory cytokines, including tumor necrosis factor alpha, interleukin-6, interleukin-1β, and chemokine (C-C motif) ligand 5, after JEV infection, whereas knockdown of miR-19b-3p had completely opposite effects. Mechanistically, miR-19b-3p modulated the JEV-induced inflammatory response via targeting ring finger protein 11, a negative regulator of nuclear factor kappa B signaling. We also found that inhibition of ring finger protein 11 by miR-19b-3p resulted in accumulation of nuclear factor kappa B in the nucleus, which in turn led to higher production of inflammatory cytokines.In vivosilencing of miR-19b-3p by a specific antagomir reinvigorates the expression level of RNF11, which in turn reduces the production of inflammatory cytokines, abrogates gliosis and neuronal cell death, and eventually improves the survival rate in the mouse model. Collectively, our results demonstrate that miR-19b-3p positively regulates the JEV-induced inflammatory response. Thus, miR-19b-3p targeting may constitute a thought-provoking approach to rein in JEV-induced inflammation. Japanese encephalitis virus (JEV) is one of the major causes of acute encephalitis in humans worldwide. The pathological features of JEV-induced encephalitis are inflammatory reactions and neurological diseases

  4. Epidemiological trends and characteristics of Japanese encephalitis changed based on the vaccination program between 1960 and 2013 in Guangxi Zhuang Autonomous Region, southern China

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    Yan Yang

    2016-04-01

    Full Text Available Japanese encephalitis (JE is one of the most severe kinds of viral encephalitis and is prevalent in Asia and the Western Pacific. In China, JE was first reported in the 1940s and became the main cause of viral encephalitis, including in the Guangxi Zhuang Autonomous Region. In 1951, JE was included in the Chinese mandatory disease reporting system. In the pre-vaccine era of the 1960s and 1970s, the incidence of JE continued to rise without any vaccine supply. Since JE vaccines became available in the late 1970s (MBD and 1989 (LAV-SA-14-14-2, and as JE vaccine became freely available to patients beginning in 2008, the incidence of JE has declined significantly. Despite these gains, outbreaks continue to occur among children in rural and suburban areas. Strengthening vaccine delivery models and improving swine vaccine production are important in order to sustain continuous declines in the incidence of JE in Guangxi.

  5. Isolation of saint louis encephalitis virus from a horse with neurological disease in Brazil.

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    Roberta Rosa

    2013-11-01

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

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

    Science.gov (United States)

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

    2013-01-01

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

  7. Cerebrospinal Fluid Biomarkers of Japanese Encephalitis [v1; ref status: indexed, http://f1000r.es/5n3

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    Nabonita Sengupta

    2015-07-01

    Full Text Available Japanese encephalitis (JE is the leading cause of viral encephalitis in Asia. Acute encephalitis syndrome (AES is a group of central nervous system (CNS disorders caused by a wide range of viruses, bacteria, fungi, chemicals and toxins. It is important to distinguish between various forms of infectious encephalitis with similar clinical manifestations in order to ensure specific and accurate diagnosis and development of subsequent therapeutic strategies. Cerebrospinal fluid (CSF is in direct contact with the CNS and hence it is considered to be an excellent source for identifying biomarkers for various neurological disorders. With the recent advancement in proteomic methodologies, the field of biomarker research has received a remarkable boost.  The present study identifies potential biomarkers for JE using a proteomics based approach. The CSF proteomes from ten patients each with JE and Non-JE acute encephalitis were analyzed by 2D gel electrophoresis followed by mass spectrometry. Vitamin D-binding protein (DBP, fibrinogen gamma chain, fibrinogen beta chain, complement C4-B, complement C3 and cytoplasmic actin were found to be significantly elevated in case of JE indicating severe disruption of the blood brain barrier and DBP can be suggested to be an important diagnostic marker.

  8. Seasonal abundance & role of predominant Japanese encephalitis vectors Culex tritaeniorhynchus & Cx. gelidus Theobald in Cuddalore district, Tamil Nadu

    Science.gov (United States)

    Ramesh, D.; Muniaraj, M.; Samuel, P. Philip; Thenmozhi, V.; Venkatesh, A.; Nagaraj, J.; Tyagi, B.K.

    2015-01-01

    Background & objectives: Japanese encephalitis (JE) is the leading cause of viral encephalitis in Asia. The first major JE outbreak occurred in 1978 and since 1981 several outbreaks had been reported in the Cuddalore district (erstwhile South Arcot), Tamil Nadu, India. Entomological monitoring was carried out during January 2010 - March 2013, to determine the seasonal abundance and transmission dynamics of the vectors of JE virus, with emphasis on the role of Culex tritaeniorhynchus and Cx. gelidus. Methods: Mosquito collections were carried out fortnightly during dusk hours in three villages viz. Soundara Solapuram, Pennadam, Erappavur of Cuddalore district. Mosquitoes were collected during dusk for a period of one hour in and around the cattle sheds using oral aspirator and torch light. The collected mosquitoes were later identified and pooled to detect JE virus (JEV) infection by enzyme linked immunosorbent assay (ELISA). Results: A total of 46,343 mosquitoes comprising of 25 species and six genera were collected. Species composition included viz, Cx. tritaeniorhynchus (46.26%), Cx. gelidus (43.12%) and other species (10.62%). A total of 17,678 specimens (403 pools) of Cx. gelidus and 14,358 specimens (309 pools) of Cx. tritaeniorhynchus were tested, of which 12 pools of Cx. gelidus and 14 pools of Cx. tritaeniorhynchus were positive for JE virus antigen. The climatic factors were negatively correlated with minimum infection rate (MIR) for both the species, except mean temperature (P<0.05) for Cx. gelidus. Interpretation & conclusions: High abundance of Cx. tritaeniorhynchus and Cx. gelidus was observed compared to other mosquito species in the study area. Detection of JEV antigen in the two species confirmed the maintenance of virus. Appropriate vector control measures need to be taken to reduce the vector abundance. PMID:26905238

  9. Infection of human endothelial cells by Japanese encephalitis virus: increased expression and release of soluble HLA-E.

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    Shwetank

    Full Text Available Japanese encephalitis virus (JEV is a single stranded RNA virus that infects the central nervous system leading to acute encephalitis in children. Alterations in brain endothelial cells have been shown to precede the entry of this flavivirus into the brain, but infection of endothelial cells by JEV and their consequences are still unclear. Productive JEV infection was established in human endothelial cells leading to IFN-β and TNF-α production. The MHC genes for HLA-A, -B, -C and HLA-E antigens were upregulated in human brain microvascular endothelial cells, the endothelial-like cell line, ECV 304 and human foreskin fibroblasts upon JEV infection. We also report the release/shedding of soluble HLA-E (sHLA-E from JEV infected human endothelial cells for the first time. This shedding of sHLA-E was blocked by an inhibitor of matrix metalloproteinases (MMP. In addition, MMP-9, a known mediator of HLA solubilisation was upregulated by JEV. In contrast, human fibroblasts showed only upregulation of cell-surface HLA-E. Addition of UV inactivated JEV-infected cell culture supernatants stimulated shedding of sHLA-E from uninfected ECV cells indicating a role for soluble factors/cytokines in the shedding process. Antibody mediated neutralization of TNF-α as well as IFNAR receptor together not only resulted in inhibition of sHLA-E shedding from uninfected cells, it also inhibited HLA-E and MMP-9 gene expression in JEV-infected cells. Shedding of sHLA-E was also observed with purified TNF-α and IFN-β as well as the dsRNA analog, poly (I:C. Both IFN-β and TNF-α further potentiated the shedding when added together. The role of soluble MHC antigens in JEV infection is hitherto unknown and therefore needs further investigation.

  10. A preliminary randomized double blind placebo-controlled trial of intravenous immunoglobulin for Japanese encephalitis in Nepal.

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    Ajit Rayamajhi

    Full Text Available Japanese encephalitis (JE virus (JEV is a mosquito-borne flavivirus found across Asia that is closely related to West Nile virus. There is no known antiviral treatment for any flavivirus. Results from in vitro studies and animal models suggest intravenous immunoglobulin (IVIG containing virus-specific neutralizing antibody may be effective in improving outcome in viral encephalitis. IVIG's anti-inflammatory properties may also be beneficial.We performed a pilot feasibility randomized double-blind placebo-controlled trial of IVIG containing anti-JEV neutralizing antibody (ImmunoRel, 400mg/kg/day for 5 days in children with suspected JE at two sites in Nepal; we also examined the effect on serum neutralizing antibody titre and cytokine profiles. 22 children were recruited, 13 of whom had confirmed JE; 11 received IVIG and 11 placebo, with no protocol violations. One child (IVIG group died during treatment and two (placebo subsequently following hospital discharge. Overall, there was no difference in outcome between treatment groups at discharge or follow up. Passive transfer of anti-JEV antibody was seen in JEV negative children. JEV positive children treated with IVIG had JEV-specific neutralizing antibody titres approximately 16 times higher than those treated with placebo (p=0.2, which was more than could be explained by passive transfer alone. IL-4 and IL-6 were higher in the IVIG group.A trial of IVIG for JE in Nepal is feasible. IVIG may augment the development of neutralizing antibodies in JEV positive patients. IVIG appears an appealing option for JE treatment that warrants further study.ClinicalTrials.gov NCT01856205.

  11. Seasonal abundance & role of predominant Japanese encephalitis vectors Culex tritaeniorhynchus & Cx. gelidus Theobald in Cuddalore district, Tamil Nadu.

    Science.gov (United States)

    Ramesh, D; Muniaraj, M; Samuel, P Philip; Thenmozhi, V; Venkatesh, A; Nagaraj, J; Tyagi, B K

    2015-12-01

    Japanese encephalitis (JE) is the leading cause of viral encephalitis in Asia. The first major JE outbreak occurred in 1978 and since 1981 several outbreaks had been reported in the Cuddalore district (erstwhile South Arcot), Tamil Nadu, India. Entomological monitoring was carried out during January 2010 - March 2013, to determine the seasonal abundance and transmission dynamics of the vectors of JE virus, with emphasis on the role of Culex tritaeniorhynchus and Cx. gelidus. Mosquito collections were carried out fortnightly during dusk hours in three villages viz. Soundara Solapuram, Pennadam, Erappavur of Cuddalore district. Mosquitoes were collected during dusk for a period of one hour in and around the cattle sheds using oral aspirator and torch light. The collected mosquitoes were later identified and pooled to detect JE virus (JEV) infection by enzyme linked immunosorbent assay (ELISA). A total of 46,343 mosquitoes comprising of 25 species and six genera were collected. Species composition included viz, Cx. tritaeniorhynchus (46.26%), Cx. gelidus (43.12%) and other species (10.62%). A total of 17,678 specimens (403 pools) of Cx. gelidus and 14,358 specimens (309 pools) of Cx. tritaeniorhynchus were tested, of which 12 pools of Cx. gelidus and 14 pools of Cx. tritaeniorhynchus were positive for JE virus antigen. The climatic factors were negatively correlated with minimum infection rate (MIR) for both the species, except mean temperature (P<0.05) for Cx. gelidus. High abundance of Cx. tritaeniorhynchus and Cx. gelidus was observed compared to other mosquito species in the study area. Detection of JEV antigen in the two species confirmed the maintenance of virus. Appropriate vector control measures need to be taken to reduce the vector abundance.

  12. Regional variation in pig farmer awareness and actions regarding Japanese encephalitis in Nepal: implications for public health education.

    Science.gov (United States)

    Dhakal, Santosh; Joshi, Durga Datt; Ale, Anita; Sharma, Minu; Dahal, Meena; Shah, Yogendra; Pant, Dhan Kumar; Stephen, Craig

    2014-01-01

    Japanese encephalitis (JE) is a mosquito-borne zoonotic disease that has pigs as the major amplifying hosts. It is the most important cause of viral encephalitis in people in Nepal and is spreading in its geographic distribution in that country. Pig farming is increasing in Nepal due to reducing cultural biases against pigs and government programs to support pig farming for poverty alleviation. Major strategies for JE prevention and control include education, vector control, and immunization of people and pigs. This study used a survey of 400 pig farmers in 4 areas of Nepal with different JE and pig farming histories to explore regional variations in farmer awareness and actions towards JE, the association of awareness and actions with farm and farmer variables, and the implications of these associations for public health education. Exposure to JE risk factors was common across pig farms and pig farming districts but there were significant district level differences in knowledge and practices related to on-farm JE risk reduction. Social factors such as literacy, gender, and cultural practices were associated with farmer attitudes, knowledge and practices for JE control. JE vaccine uptake was almost non-existent and mosquito control steps were inconsistently applied across all 4 districts. Income was not a determining factor of the differences, but all farmers were very poor. The low uptake of vaccine and lack of infrastructure or financial capacity to house pigs indoors or away from people suggest that farmer personal protection should be a priority target for education in Nepal. This study re-enforces the need to attack root causes of people's personal disease prevention behaviours and take into account local variation in needs and capacities when designing health or agriculture education programs.

  13. Regional variation in pig farmer awareness and actions regarding Japanese encephalitis in Nepal: implications for public health education.

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    Santosh Dhakal

    Full Text Available Japanese encephalitis (JE is a mosquito-borne zoonotic disease that has pigs as the major amplifying hosts. It is the most important cause of viral encephalitis in people in Nepal and is spreading in its geographic distribution in that country. Pig farming is increasing in Nepal due to reducing cultural biases against pigs and government programs to support pig farming for poverty alleviation. Major strategies for JE prevention and control include education, vector control, and immunization of people and pigs. This study used a survey of 400 pig farmers in 4 areas of Nepal with different JE and pig farming histories to explore regional variations in farmer awareness and actions towards JE, the association of awareness and actions with farm and farmer variables, and the implications of these associations for public health education. Exposure to JE risk factors was common across pig farms and pig farming districts but there were significant district level differences in knowledge and practices related to on-farm JE risk reduction. Social factors such as literacy, gender, and cultural practices were associated with farmer attitudes, knowledge and practices for JE control. JE vaccine uptake was almost non-existent and mosquito control steps were inconsistently applied across all 4 districts. Income was not a determining factor of the differences, but all farmers were very poor. The low uptake of vaccine and lack of infrastructure or financial capacity to house pigs indoors or away from people suggest that farmer personal protection should be a priority target for education in Nepal. This study re-enforces the need to attack root causes of people's personal disease prevention behaviours and take into account local variation in needs and capacities when designing health or agriculture education programs.

  14. An in vitro recombination-based reverse genetic system for rapid mutagenesis of structural genes of the Japanese encephalitis virus

    Institute of Scientific and Technical Information of China (English)

    Ruikun; Du; Manli; Wang; Zhihong; Hu; Hualin; Wang; Fei; Deng

    2015-01-01

    Japanese encephalitis virus(JEV) is one of the most common pathogens of severe viral encephalitis, which is a severe threat to human health. Despite instability of the JEV genome in bacteria, many strategies have been developed to establish molecular clone systems of JEV, providing convenient tools for studying the virus life cycle and virus–host interactions. In this study, we adapted an In-Fusion enzyme-based in vitro recombination method to construct a reverse genetic system of JEV, thereby providing a rapid approach to introduce mutations into the structural genes. A truncated genome without the structural genes was constructed as the backbone, and the complementary segment containing the structural genes was recombined in vitro, which was then transfected directly into virus-permissive cells. The progeny of the infectious virus was successfully detected in the supernatant of the transfected cells, and showed an identical phenotype to its parental virus. To provide a proof-of-principle, the 12 conserved cysteine residues in the envelope(E) protein of JEV were respectively mutated using this approach, and all mutations resulted in a complete failure to generate infectious virus. However, a leucine-tophenylanine mutation at amino acid 107 of the E protein did not interfere with the production of the infectious virus. These results suggested that all 12 cysteines in the E protein are essential for the JEV life cycle. In summary, a novel reverse genetic system of JEV was established for rapidly introducing mutations into structural genes, which will serve as a useful tool for functional studies.

  15. Dengue Virus Seroconversion in Travelers to Dengue-Endemic Areas.

    Science.gov (United States)

    Olivero, Rosemary M; Hamer, Davidson H; MacLeod, William B; Benoit, Christine M; Sanchez-Vegas, Carolina; Jentes, Emily S; Chen, Lin H; Wilson, Mary E; Marano, Nina; Yanni, Emad A; Ooi, Winnie W; Karchmer, Adolf W; Kogelman, Laura; Barnett, Elizabeth D

    2016-11-02

    We conducted a prospective study to measure dengue virus (DENV) antibody seroconversion in travelers to dengue-endemic areas. Travelers seen in the Boston Area Travel Medicine Network planning to visit dengue-endemic countries for ≥ 2 weeks were enrolled from 2009 to 2010. Pre- and post-travel blood samples and questionnaires were collected. Post-travel sera were tested for anti-DENV IgG by indirect IgG enzyme-linked immunosorbent assay (ELISA) and anti-DENV IgM by capture IgM ELISA. Participants with positive post-travel anti-DENV IgG or IgM were tested for pre-travel anti-DENV IgG and IgM; they were excluded from the seroconversion calculation if either pre-travel anti-DENV IgG or IgM were positive. Paired sera and questionnaires were collected for 62% (589/955) of enrolled travelers. Most participants were 19-64 years of age, female, and white. The most common purposes of travel were tourism and visiting friends and relatives; most trips were to Asia or Africa. Median length of travel was 21 days. DENV antibody seroconversion by either anti-DENV IgM or IgG ELISA was 2.9-6.8%; lower range percent excluded potential false-positive anti-DENV IgG due to receipt of yellow fever or Japanese encephalitis vaccines at enrollment; upper range percent excluded proven false-positive anti-DENV IgM. Eighteen percent of those with seroconversion reported dengue-like symptoms. Seroconversion was documented for travel to Africa as well as countries and regions known to be highly dengue endemic (India, Brazil, southeast Asia). Given widespread risk of dengue, travel medicine counseling should include information on risk of dengue in endemic areas and advice on preventing insect bites and seeking prompt medical attention for febrile illness.

  16. Studies on the phenotypic and genotypic characteristics of SA14 wild Japanese encephalitis virus and its attenuated viruses

    Institute of Scientific and Technical Information of China (English)

    XING LIANG FAN; YONG XIN YU; DE FU LI; ZHI HUI YAO; LI LI JIA

    2006-01-01

    The aim of this study was to explore the molecular basis for the attenuation of the Japanese encephalitis virus (JEV) vaccine strain SA14-14-2. The virulence of SA14 wild Japanese encephalitis virus (JEV) and its several attenuated viruses was tested by intracerebral (i. c. ) or intraperitonial (i. p. ) inoculation of 10-12 g mice. The stability of neuroattenuation was tested by one passage in suckling mouse brain. The E protein genes of those viruses were amplified by PCR, sequenced and compared. Three attenuated virus strains, SA14-14-2 vaccine virus, SA14-9-7 and SA14-5-3, did not exhibit lethal infections by i.c. or i.p. inoculation of 10-12 g mice and revert to the virulence. The other virus strain, SA14-12-1-7, showed no neuroinvasiveness by i.p. inoculation but residual neurovirulence by i.c. inoculation and reverted to high virulence after one brain passage. Comparison of the E protein gene sequences of the five virus strains indicated that there were differences of twelve nucleotides and eight amino acids between the parent strain SA14 and vaccine strain SA14-14-2, of which six amino acids (E-107, E-176, E-439, E138, E-279, E-315) exhibited changes common to those of SA14-9-7 and SA14-5-3, three substitutions common to SA14-12-1-7. Two amino acid substitutions at the sites E177 (T→A) and E264 (Q→H) are unique to the SA14-14-2 vaccine virus. The results suggest that the mutations of E-107 (Leu→Phe), E176 (Ile→Val), and E-439 (Lys→Arg) may contribute for the attenuation of neuroinvasiveness and partially for the attenuation of neurovirulence, the mutations of E-138, E-279, E-315 may not only critical to the neuroattenuation but also to its stability.

  17. Seroprevalence of antibodies against dengue virus among pregnant women in the Democratic Republic of Sao Tome and Principe.

    Science.gov (United States)

    Yen, Tsai-Ying; Trovoada dos Santos, Maria de Jesus; Tseng, Lien-Feng; Chang, Shu-Feng; Cheng, Chien-Fu; Carvalho, Arlindo Vicente de Assunção; Shu, Pei-Yun; Lien, Jih-Ching; Tsai, Kun-Hsien

    2016-03-01

    Dengue fever has become a worldwide public health concern, threatening an estimated 40% of the world's population. However, most resources and attention are still focused on malaria, while dengue statuses are poorly recognized in many African countries. In this serological survey, dengue virus (DENV) transmission was demonstrated by using serum samples collected from 78 pregnant women in the Democratic Republic of Sao Tome and Principe (DRSTP) during 2003 to 2004. Immunofluorescence assay was performed and 31 samples (39.74%) were found positive for DENV antibodies. Indirect enzyme-linked immunosorbent assay (ELISA) showed that 53 samples (67.95%) were positive for dengue E IgG, and 38 samples (48.72%) were positive for NS1 IgG. A prevalence of 35.90% was therefore determined for dengue IgG by considering samples that yielded positive results by all three tests. Cross-reactions with other flaviviruses were examined by indirect ELISA against Japanese encephalitis virus, West Nile virus, and yellow fever virus. Only one sample exhibited stronger absorbance against Japanese encephalitis virus and West Nile virus. Moreover, one sample was positive for dengue IgM. These results agreed with the previous researches in neighboring countries and suggested DENV exposure. The study contributes to raising public awareness of dengue and supporting future control strategies.

  18. Protection of SA14-14-2 live attenuated Japanese encephalitis vaccine against the wild-type JE viruses

    Institute of Scientific and Technical Information of China (English)

    贾丽丽; 王志伟; 俞永新

    2003-01-01

    ObjectiveTo explore on the immunity of live attenuated Japanese Encephalitis (JE) vaccine(SA14-14-2) to different wild JE virus (JEV) strains. MethodsThe neutralizing effect of the vaccine against different wild JE virus strains was detected by plaque reduction neutralization test (PRNT), and the immunogenicity was studied on mice by vaccination -challenge protection test. In the PRNT , pooled sera from vaccinated human were tested against 10 strains of JEV , one isolated in Taiwan and 9 from other Asian countries.In the vaccination challenge test, mice received one dose of the live vaccine subcutaneously and were challenged intraperitoneally 14 days later against 22 JEV virus strains, 11 were isolated in China and the other 11 from Tailand, Vietnahailam, Indonesia, India, Philippines and Japan. ResultsThe protection rates to all the 22 challenge virus were 90%-100% when 340 PFU/0.1 ml vaccinate virus was administered. The neutralizing effect showed that all the JEV isolates many have neutralized by the sera. ConclusionSA14-14-2 live attenuated prepared with strain SA14-14-2 is broadly immunogenic and may have effective protection against in Asian JE affected countries.

  19. Japanese B Encephalitis: An Overview of the Disease and Use of Chimerivax-JE as a Preventative Vaccine.

    Science.gov (United States)

    Chin, Ruth; Torresi, Joseph

    2013-12-01

    The Japanese encephalitis virus (JEV) is endemic in many countries in southern Asia and the western Pacific Rim, with new spread to previously unrecognized countries. It is an important cause of childhood neurological disease associated with permanent neurological sequelae and death. Fortunately, JE is a vaccine-preventable disease. The ChimeriVax™-JE (Sanofi Pasteur, Lyon, France) is a live-attenuated chimeric vaccine derived from the live-attenuated yellow fever virus, YF17D, which expresses the envelope proteins of the attenuated JEV vaccine strain, SA14-14-2. It is a safe, well-tolerated vaccine that is highly immunogenic in adults and children. The average geometric mean neutralizing antibody titer (GMT) in adults is 1,392 and over 90% of adults remain seroprotected 5 years after vaccination. In children and toddlers, more than 80% remain seroprotected 2 years after primary vaccination and demonstrate a robust and durable anamnestic response (>500-fold rise in GMT) with 99.1% seroprotection rates 1 year after a booster vaccine dose. The ChimeriVax™-JE is effective in children living in endemic regions where the vaccine could possibly be integrated into existing childhood vaccination programs. ChimeriVax™-JE is also indicated for travelers at risk of JE infection.

  20. Effectiveness of the Viet Nam produced, mouse brain-derived, inactivated Japanese encephalitis vaccine in Northern Viet Nam.

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    Florian Marks

    Full Text Available BACKGROUND: Japanese encephalitis (JE is a flaviviral disease of public health concern in many parts of Asia. JE often occurs in large epidemics, has a high case-fatality ratio and, among survivors, frequently causes persistent neurological sequelae and mental disabilities. In 1997, the Vietnamese government initiated immunization campaigns targeting all children aged 1-5 years. Three doses of a locally-produced, mouse brain-derived, inactivated JE vaccine (MBV were given. This study aims at evaluating the effectiveness of Viet Nam's MBV. METHODOLOGY: A matched case-control study was conducted in Northern Viet Nam. Cases were identified through an ongoing hospital-based surveillance. Each case was matched to four healthy controls for age, gender, and neighborhood. The vaccination history was ascertained through JE immunization logbooks maintained at local health centers. PRINCIPAL FINDINGS: Thirty cases and 120 controls were enrolled. The effectiveness of the JE vaccine was 92.9% [95% CI: 66.6-98.5]. Confounding effects of other risk variables were not observed. CONCLUSIONS: Our results strongly suggest that the locally-produced JE-MBV given to 1-5 years old Vietnamese children was efficacious.

  1. Japanese Encephalitis vector abundance and infection frequency in Cuddalore District, Tamil Nadu, India: a five-year longitudinal study

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    P. Philip Samuel

    2016-12-01

    Full Text Available An entomological monitoring of Japanese encephalitis vectors from the Cuddalore district, Tamil Nadu was undertaken at biweekly intervals for 1 hr after dusk for five years to find out the abundance and JE virus activity longitudinally in three villages. A total of 95,644 vectors belonging to 31 species constituted predominantly by Culex vishnui subgroup and Culex gelidus 98.5%. JE virus was identified from Cx. tritaeniorhynchus (18, Cx. vishnui (1 and Cx. gelidus (6 giving infection rate of 0.482, 0.608 and 0.221 respectively. Abundance of Cx. tritaeniorhynchus and Cx. gelidus differed significantly by area, season and year (P<0.05 whereas Cx. vishuni differed significantly by season and year (P<0.05. Transmission was not observed throughout all the seasons and the infection rate was recorded maximum during Hot-Wet season 0.46 (confidence interval: 0.17-1.02. Culex tritaeniorhynchus dominated the catch and the Culex gelidus steadily increased in its abundance during this period compared to the earlier studies conducted from these areas which acts as a secondary vector along with the major vector, Cx. tritaeniorhynchus.

  2. Characterization of the GXXXG motif in the first transmembrane segment of Japanese encephalitis virus precursor membrane (prM) protein.

    Science.gov (United States)

    Lin, Ying-Ju; Peng, Jia-Guan; Wu, Suh-Chin

    2010-05-24

    The interaction between prM and E proteins in flavivirus-infected cells is a major driving force for the assembly of flavivirus particles. We used site-directed mutagenesis to study the potential role of the transmembrane domains of the prM proteins of Japanese encephalitis virus (JEV) in prM-E heterodimerization as well as subviral particle formation. Alanine insertion scanning mutagenesis within the GXXXG motif in the first transmembrane segment of JEV prM protein affected the prM-E heterodimerization; its specificity was confirmed by replacing the two glycines of the GXXXG motif with alanine, leucine and valine. The GXXXG motif was found to be conserved in the JEV serocomplex viruses but not other flavivirus groups. These mutants with alanine inserted in the two prM transmembrane segments all impaired subviral particle formation in cell cultures. The prM transmembrane domains of JEV may play importation roles in prM-E heterodimerization and viral particle assembly.

  3. Longitudinal studies of Japanese encephalitis virus infection in vector mosquitoes in Kurnool district, Andhra Pradesh, South India.

    Science.gov (United States)

    Arunachalam, N; Murty, U S N; Narahari, D; Balasubramanian, A; Samuel, P Philip; Thenmozhi, V; Paramasivan, R; Rajendran, R; Tyagi, B K

    2009-05-01

    A 4-yr (2002-2006) entomological study was carried out in Kurnool district, Andhra Pradesh state, south India, to identify the mosquito vectors of Japanese encephalitis virus (family Flaviviridae, genus Flavivirus, JEV). In total, 37,139 female mosquitoes belonging five genera and 18 species resting on vegetation were collected in villages and periurban areas at dusk. Mosquito species composition and pattern of JEV infection in mosquitoes varied in periurban and rural areas. In periurban area, Culex gelidus Theobald was abundant, making up 49.7% of total catch followed by Culex tritaeniorhynchus Giles (44.5%). In rural area, Cx. tritaeniorhynchus was predominant, making up 78.9% of total catch followed by Culex quinquefasciatus Say (10.8%), Anopheles subpictus Grassi (7.1%), and Cx. gelidus (1.1%). In light trap collections, Cx. gelidus and Cx. tritaeniorhynchus predominated in periurban and rural areas, respectively. Of 50,145 mosquitoes screened JEV isolations were made only from Cx. gelidus and Cx. tritaeniorhynchus. Based on high abundance and frequent JEV isolation, Cx. tritaeniorhynchus was found to be the principal vector in both areas, whereas Cx. gelidus plays a secondary vector role in periurban areas only.

  4. Development of electrochemical immunosensors based on different serum antibody immobilization methods for detection of Japanese encephalitis virus

    Science.gov (United States)

    Tran, Quang Huy; Hanh Nguyen, Thi Hong; Mai, Anh Tuan; Thuy Nguyen, Thi; Khue Vu, Quang; Nga Phan, Thi

    2012-03-01

    This paper describes the development of electrochemical immunosensors based on human serum antibodies with different immobilization methods for detection of Japanese encephalitis virus (JEV). Human serum containing anti-JEV antibodies was used to immobilize onto the surface of silanized interdigitated electrodes by four methods: direct adsorption (APTES-serum), covalent binding with a cross linker of glutaraldehyde (APTES-GA-serum), covalent binding with a cross linker of glutaraldehyde combined with anti-human IgG (APTES-GA-anti-HIgG-serum) and covalent binding with a cross linker of glutaraldehyde combined with a bioaffinity of protein A (APTES-GA-PrA-serum). Atomic force microscopy was used to verify surface characteristics of the interdigitated electrodes before and after treatment with serum antibodies. The output signal of the immunosensors was measured by the change of conductivity resulting from the specific binding of JEV antigens and serum antibodies immobilized on the electrodes, with the help of horseradish peroxidase (HRP)-labeled secondary antibody against JEV. The results showed that the APTES-GA-PrA-serum method provided the highest signal of the electrochemical immunosensor for detection of JEV antigens, with the linear range from 25 ng ml-1 to 1 μg ml-1, and the limit of detection was about 10 ng ml-1. This study shows a potential development of novel electrochemical immunosensors applied for virus detection in clinical samples in case of possible outbreaks.

  5. Characterization of immune responses induced by inactivated, live attenuated and DNA vaccines against Japanese encephalitis virus in mice.

    Science.gov (United States)

    Li, Jieqiong; Chen, Hui; Wu, Na; Fan, Dongying; Liang, Guodong; Gao, Na; An, Jing

    2013-08-28

    Vaccination is the most effective countermeasure for protecting individuals from Japanese encephalitis virus (JEV) infection. There are two types of JEV vaccines currently used in China: the Vero cell-derived inactivated vaccine and the live attenuated vaccine. In this study, we characterized the immune response and protective efficacy induced in mice by the inactivated vaccine, live attenuated vaccine and the DNA vaccine candidate pCAG-JME, which expresses JEV prM-E proteins. We found that the live attenuated vaccine conferred 100% protection and resulted in the generation of high levels of specific anti-JEV antibodies and cytokines. The pCAG-JME vaccine induced protective immunity as well as the live attenuated vaccine. Unexpectedly, immunization with the inactivated vaccine only induced a limited immune response and partial protection, which may be due to the decreased activity of dendritic cells and the expansion of CD4+CD25+Foxp3+ regulatory T cells observed in these mice. Altogether, our results suggest that the live attenuated vaccine is more effective in providing protection against JEV infection than the inactivated vaccine and that pCAG-JME will be a potential JEV vaccine candidate. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. A critical appraisal of Ixiaro® – a cell-derived inactivated vaccine for Japanese encephalitis

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    Taff Jones

    2009-11-01

    Full Text Available Taff JonesClinical Testing Laboratories, Medimmune, Mountain View, CA, USAAbstract: Japanese encephalitis is a disease prevalent across a huge swathe of southeast Asia. The number of reported cases of the disease is increasing in countries that do not have a vaccination program, but in contrast, is decreasing in countries that have implemented mass vaccination programs. Clearly vaccination is having some impact, and although visitors to the area are generally thought to be at low risk, vaccination is recommended for those staying 1 month or longer. Until recently, the only licensed vaccine available to them, JE-VAX®, was made from virus propagated in mouse brain, and among Western Hemisphere recipients of this vaccine, many side effects and adverse events were reported, and production of the vaccine was discontinued in 2007. A new vaccine, Ixiaro®, has recently been licensed. The vaccine comprises inactivated virus, previously propagated in Vero cells, adsorbed onto an alum adjuvant. In extensive clinical trials in both adult and pediatric populations, Ixiaro® has proven non-inferior to JE-VAX® in terms of immunogenicity and seroconversion, but with an improved safety and tolerability profile compared with JE-VAX®.Keywords: vero cells, JEV, vaccine

  7. Japanese encephalitis virus expands regulatory T cells by increasing the expression of PD-L1 on dendritic cells.

    Science.gov (United States)

    Gupta, Nimesh; Hegde, Pushpa; Lecerf, Maxime; Nain, Minu; Kaur, Manpreet; Kalia, Manjula; Vrati, Sudhanshu; Bayry, Jagadeesh; Lacroix-Desmazes, Sébastien; Kaveri, Srini V

    2014-05-01

    The mechanisms underlying Japanese encephalitis virus (JEV) pathogenesis need to be thoroughly explored to delineate therapeutic approaches. It is believed that JEV manipulates the innate and adaptive compartments of the host's immune system to evade immune response and cross the blood-brain barrier. The present study was thus designed to investigate the functional modulation of DCs after exposure to JEV and to assess the consequences on CD4(+) T-lymphocyte functions. Human monocyte-derived DCs were either infected with 1 MOI of live virus, UV-inactivated virus, or were mock-infected. Replication-competent JEV induced a significant increase in the expression of maturation markers 48 h postinfection, along with that of programmed cell death 1 ligand 1 (PD-L1; also called B7-H1 and CD274). JEV-infected DCs expanded the Treg cells in allogenic mixed lymphocyte reactions. The expansion of Treg cells by JEV-infected DCs was significantly reduced upon blocking PD-L1 using an antagonist. In addition, JEV-infected DCs significantly altered the proliferation and reduced the polarization of Th cells toward the Th1-cell phenotype. The results, for the first time, suggest that JEV evades the host's immune system by modulating the crosstalk between DCs and T lymphocytes via the PD-L1 axis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Seasonal abundance and potential of Japanese encephalitis virus infection in mosquitoes at the nesting colony of ardeid birds, Thailand

    Institute of Scientific and Technical Information of China (English)

    Tanasak Changbunjong; Thekhawet Weluwanarak; Namaoy Taowan; Parut Suksai; Tatiyanuch Chamsai; Poonyapat Sedwisai

    2013-01-01

    Objective:To investigate the abundance and seasonal dynamics of mosquitoes, and to detect Japanese encephalitis virus (JEV) in these mosquitoes at the nesting colony of ardeid birds. Methods: Mosquitoes were collected bimonthly from July 2009 to May 2010 by Centers for Disease Control. Light traps and dry ice, as a source of CO2, were employed to attract mosquitoes. Mosquitoes were first identified, pooled into groups of upto 50 mosquitoes by species, and tested for JEV infection by viral isolation and reverse transcriptase polymerase chain reaction. Results:A total of 20 370 mosquitoes comprising 14 species in five genera were collected. The five most abundant mosquito species collected were Culex tritaeniorhynchus (95.46%), Culex vishnui (2.68%), Culex gelidus (0.72%), Anopheles peditaeniatus (0.58%) and Culex quinquefasciatus (0.22%). Mosquito peak densities were observed in July. All of 416 mosquito pools were negative for JEV. Conclusions: This study provides new information about mosquito species and status of JEV infection in mosquitoes in Thailand. Further study should be done to continue a close survey for the presence of this virus in the ardeid birds.

  9. Long-term stability of Vero cell-derived inactivated Japanese encephalitis vaccine prepared using serum-free medium.

    Science.gov (United States)

    Toriniwa, Hiroko; Komiya, Tomoyoshi

    2008-07-04

    We established a method of producing a Vero cell-derived Japanese encephalitis vaccine using serum-free medium, and tested its stability using various stabilizers during the inactivation process and storage at 4 degrees C and 28 degrees C. Similar to previously reported results of cell culture in serum-containing medium, Vero cells were cultured in a serum-free medium multiplied well, and the viral yield was successfully increased to about 10(9)PFU/ml. Following formalin-inactivation and purification via ethanol precipitation and sucrose density ultracentrifugation of the virus solution, the vaccine had the same quality as, and higher immunogenicity, the mouse brain-derived vaccine in current use. Testing of several stabilizers showed that the addition of 0.5% glycine during the virus inactivation process facilitated the maintenance of immunogenicity for a long period of time. Furthermore, the addition of 0.5% glycine and 1.0% sorbitol as vaccine stabilizers after purification led to the maintenance of immunogenicity for 1 year, not dependent on the storage temperature (4 degrees C or 28 degrees C). These results indicate that, in contrast to the current mouse brain-derived vaccine, the Vero cell-derived vaccine can be prepared using serum-free medium containing no animal-derived components, and that the vaccine can be stored at room temperature by adding stabilizers, suggesting the possibility of producing room temperature-stable vaccines.

  10. Review of Japanese Encephalitis Vaccine%乙型脑炎疫苗研究现状及展望

    Institute of Scientific and Technical Information of China (English)

    于立权; 仇华吉; 童光志

    2002-01-01

    @@ 乙型脑炎简称乙脑,是由日本脑炎病毒(Japanese encephalitis virus,JEV)引起的一种急性传染性人畜共患病.此病首次于1935年在日本马群中发生大流行,1937年日本学者证明其病原与当地人流行性脑炎病毒相同.随后,乙脑在我国、南亚、东南亚等地陆续发生.几十年来,乙脑流行给我国及周边国家造成了巨大的经济损失.Siraprapasiri等开展了实施乙脑疫苗免疫程序的风险投入和效益分析[1].我国未进行过乙脑感染的经济调查分析,猪群及其它动物流行病学、经济损失、免疫状况及防制现状均有待调查.

  11. Surface Display of Domain Ⅲ of Japanese Encephalitis Virus E Protein on Salmonella Typhimurium by Using an Ice Nucleation Protein

    Institute of Scientific and Technical Information of China (English)

    Jian-lin Dou; Tao Jing; Jing-jing Fan; Zhi-ming Yuan

    2011-01-01

    A bacterial cell surface display technique based on an ice nucleation protein has been employed for the development of live vaccine against viral infection.Due to its ubiquitous ability to invade host cells,Salmonella typhimurium might be a good candidate for displaying viral antigens.We demonstrated the surface display of domain III of Japanese encephalitis virus E protein and the enhanced green fluorescent protein on S.typhimurium BRD509 using the ice nucleation protein.The effects of the motif in the ice nucleation protein on the effective display of integral protein were also investigated.The results showed that display motifs in the protein can target integral foreign protein on the surface of S.typhimurium BRD509.Moreover,recombinant strains with surface displayed viral proteins retained their invasiveness,suggesting that the recombinant S.typhimurium can be used as live vaccine vector for eliciting complete immunogenicity.The data may yield better understanding of the mechanism by which ice nucleation protein displays foreign proteins in the Salmonella strain.

  12. The Vero cell-derived, inactivated, SA14-14-2 strain-based vaccine (Ixiaro) for prevention of Japanese encephalitis.

    Science.gov (United States)

    Erra, Elina O; Kantele, Anu

    2015-01-01

    With an estimated 68,000 cases each year, Japanese encephalitis (JE) is the leading cause of viral encephalitis in Asia. Vaccination against the disease is recommended for endemic populations and also for travelers at risk. Recently, a Vero cell-derived, inactivated, SA14-14-2 strain-based JE vaccine (JE-VC) became available for travelers from non-endemic regions, replacing the traditional mouse brain-derived vaccines. First licensed in 2009, JE-VC is currently available in Europe, the USA, Canada, Australia and several other countries. In 2013, the vaccine was approved by the European Medicines Agency and the US Food and Drug Administration for use in children. This review summarizes current data on the immunogenicity, safety and clinical use of JE-VC.

  13. Recombinant Dengue virus protein NS2B alters membrane permeability in different membrane models

    OpenAIRE

    León-Juárez, Moisés; Martínez-Castillo, Macario; Shrivastava, Gaurav; García-Cordero, Julio; Villegas-Sepulveda, Nicolás; Mondragón-Castelán, Mónica; Mondragón-Flores, Ricardo; Cedillo-Barrón, Leticia

    2016-01-01

    Background One of the main phenomena occurring in cellular membranes during virus infection is a change in membrane permeability. It has been observed that numerous viral proteins can oligomerize and form structures known as viroporins that alter the permeability of membranes. Previous findings have identified such proteins in cells infected with Japanese encephalitis virus (JEV), a member of the same family that Dengue virus (DENV) belongs to (Flaviviridae). In the present work, we investiga...

  14. Prolonged presence of effector-memory CD8 T cells in the central nervous system after dengue virus encephalitis.

    Science.gov (United States)

    van der Most, Robbert G; Murali-Krishna, Kaja; Ahmed, Rafi

    2003-01-01

    Dengue virus infection in the central nervous system (CNS) of immunized mice results in a strong influx of CD8 T cells into the brain. Whereas the kinetics of the splenic antiviral response are conventional, i.e. expansion followed by a rapid drop in the frequency of specific CD8 T cells, dengue virus-specific CD8 T cells are retained in the CNS at a high frequency. These CD8 T cells display a partially activated phenotype (CD69(high), Ly-6A/E(high), CD62L(low)), characteristic for effector-memory T cells. CD43 expression, visualized by staining with the 1B11 mAb, decreased in time, suggesting that these persisting CD8 T cells differentiated into memory cells. These data add to the growing evidence implicating the CNS as a non-lymphoid tissue capable of supporting prolonged T cell survival/maintenance.

  15. Expression of particulate-form of Japanese encephalitis virus envelope protein in a stably transfected Drosophila cell line

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    Zhang Li

    2007-02-01

    Full Text Available Abstract Background Japanese encephalitis virus (JEV, a member of the family Flaviviridae, is an important mosquito-borne human pathogen. Its envelope glycoprotein (E is the major determinant of the pathogenicity and host immune responses. In the present study, we explored the feasibility of producing recombinant JEV E protein in the virus-free Drosophila expression system. Results The coding sequence for the signal sequence of premembrane and E protein was cloned into the Drosophila expression vector pAc5.1/V5-His. A Drosophila cell line S2 was cotransfected with this construct as well as a plasmid providing hygromycin B resistance. A cell line expressing the JEV E protein was selected by immunofluoresence, confocal microscopy, and western blot analysis using three different monoclonal antibodies directed against JEV E protein. This cell line was stable in the yield of JEV E protein during two months in vitro maintenance in the presence of hygromycin B. The results showed that the recombinant E protein had an expected molecular weight of about 50 kilodalton, was immunoreactive with all three monoclonal antibodies, and found in both the cytoplasm and culture supernatant. Sucrose gradient ultracentrifugation analysis revealed that the secreted E protein product was in a particulate form. It migrated to the sucrose fraction with a density of 1.13 g/ml. Balb/c mice immunised with the sucrose fraction containing the E protein particles developed specific antibodies. These data show that functioning JEV E protein was expressed in the stable S2 cell line. Conclusion The Drosophila expression system is a more convenient, cheaper and safer approach to the production of vaccine candidates and diagnostic reagents for JEV.

  16. Molecular Characterization of Full-length Genome of Japanese Encephalitis Virus Genotype V Isolated from Tibet, China

    Institute of Scientific and Technical Information of China (English)

    LI Ming Hua; FU Shi Hong; CHEN Wei Xin; WANG Huan Yu; CAO Yu Xi; LIANG Guo Dong

    2014-01-01

    Objective To determine the molecular characterization of full-length genome of Japanese encephalitis virus (JEV) genotype V. Methods The full-length nucleotide sequences of JEV strains isolated from different locations and sources were used in sequence and phylogenetic analysis. Results The full-length genome of genotypes V JEV, XZ0934, and Muar strain were composed of 10 983 and 10 988 nucleotides respectively and shared a lower level of identity with JEV genotypes I-IV, ranging from 78.4% (G I, KV1899) to 79.7% (G III, JaGAr01), for the nucleotide sequences, and from 90.0%(G I, KV1899) to 91.8%(G III, JaGAr01) for the amino acid sequences. The open reading frame (ORF) of JEV genotype V spanned nucleotides 96 to 10 397 and encoded 3 433 amino acids. Interestingly, a comparison with JEV genotype I-IV revealed that 3 nucleotides (encoded with a serine residue) were inserted in the NS4A gene of JEV genotype V, and the insertion of nucleotides was also found in downstream of the ORF stop codon in 3’-untranslated region. Moreover, numerous amino acid mutations were observed in 3 functional domains of the E gene of JEV genotype V. Conclusion The molecular characterization of JEV genotype V is significantly different from that of the known genotypes I-IV. The mutations located in the coding region and the non-coding region may be molecular markers of JEV genotype V and warrant further studies to determine their effects on biology and immunogenicity of genotype V strains.

  17. Correlation of protection against Japanese encephalitis virus and JE vaccine (IXIARO(®)) induced neutralizing antibody titers.

    Science.gov (United States)

    Van Gessel, Yvonne; Klade, Christoph S; Putnak, Robert; Formica, Alessandra; Krasaesub, Somporn; Spruth, Martin; Cena, Bruno; Tungtaeng, Anchalee; Gettayacamin, Montip; Dewasthaly, Shailesh

    2011-08-11

    Immune sera from volunteers vaccinated in a blinded Phase 3 clinical trial with JE-VAX(®) and a new Japanese encephalitis virus (JEV) vaccine (IC51 or IXIARO), were tested for the ability to protect mice against lethal JEV challenge. Sera from IXIARO vaccinated subjects were pooled into four batches based on neutralizing antibody measured by plaque reduction neutralization test (PRNT(50) titer): high (∼200), medium (∼40-50), low (∼20) and negative (JE-VAX(®) vaccinated subjects (PRNT(50) titer∼55) and pooled JEV antibody negative pre-vaccination sera were used as controls. Groups of ten 6- to 7-week-old female ICR mice were injected intraperitoneally with 0.5 ml of each serum pool diluted 1:2 or 1:10, challenged approximately 18 h later with a lethal dose of either JEV strain SA14 (genotype III) or strain KE-093 (genotype I) and observed for 21 days. All mice in the non-immune serum groups developed clinical signs consistent with JEV infection or died, whereas high titer sera from both IXIARO and JE-VAX(®) sera protected 90-100% of the animals. Statistical tests showed similar protection against both JEV strains SA14 and KE-093 and protection correlated with the anti-JEV antibody titer of IXIARO sera as measured by PRNT(50). Ex vivo neutralizing antibody titers showed that almost all mice with a titer of 10 or greater were fully protected. In a separate study, analysis of geometric mean titers (GMTs) of the groups of mice vaccinated with different doses of IXIARO and challenged with JEV SA14 provided additional evidence that titers≥10 were protective.

  18. Tissue tropism and molecular characterization of a Japanese encephalitis virus strain isolated from pigs in southwest China.

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    Yuan, Lei; Wu, Rui; Liu, Hanyang; Wen, Xintian; Huang, Xiaobo; Wen, Yiping; Ma, Xiaoping; Yan, Qigui; Huang, Yong; Zhao, Qin; Cao, Sanjie

    2016-04-02

    Since September 2012, an epidemic has been spreading among swine in a pig farm located in Sichuan province, southwest China, which has resulted in abortion, stillbirth, and fetal mummification. The brains of stillborn pigs were collected and a previously unknown Japanese encephalitis virus (JEV), namely SCYA201201, was isolated. According to the results of agarose gel diffusion precipitation, indirect immunofluorescence analysis, neutralization testing, reverse transcription PCR (RT-PCR) amplification, and physical and chemical testing, the virus was conformed to have the characteristics of JEV. The virus titer in BHK-21 cells was 10(8.47)PFU/ml and the median lethal dose (LD50) to 3-week-old and 7-day-old mice was 1.99 log10 and 1.02 log10 PFU/LD50, respectively. The results of tissue tropism for mice showed that the viral load in the brain was significantly higher than other organs, indicating that the isolate was strongly neurotropic. Additionally, the complete genome sequence of the isolate was determined and compared with other JEV strains. Phylogenetic analysis showed that the isolate belongs to genotype I and may be an imported virus. The isolate had 88.4% nucleotide identity with the Chinese vaccine strain SA14-14-2. However, there were 69 amino acid substitutions compared with the strain SA14-14-2. Some substitutions indicated that SCYA201201 was highly neurovirulent and infective, in accordance with the results of animal testing. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Prevalence of Neutralizing Antibodies to Japanese Encephalitis Virus among High-Risk Age Groups in South Korea, 2010

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    Ju, Young Ran; Han, Myung Guk; Lee, Won-Ja; Jeong, Young Eui

    2016-01-01

    After an extensive vaccination policy, Japanese encephalitis (JE) was nearly eliminated since the mid-1980s in South Korea. Vaccination in children shifted the affected age of JE patients from children to adults. However, an abrupt increase in JE cases occurred in 2010, and this trend has continued. The present study aimed to investigate the prevalence of neutralizing antibodies to the JE virus (JEV) among high-risk age groups (≥40 years) in South Korea. A plaque reduction neutralization test was conducted to evaluate the prevalence of neutralizing antibodies to JEV in 945 subjects within four age groups (30–39, 40–49, 50–59, and 60–69 years) in 10 provinces. Of the 945 enrolled subjects, 927 (98.1%) exhibited antibodies against JEV. No significant differences were found in the prevalence of neutralizing antibodies according to sex, age, or occupation. However, there were significant differences in the plaque reduction rate according to age and occupation; oldest age group had a higher reduction rate, and subjects who were employed in agriculture or forestry also had a higher value than the other occupations. We also found that three provinces (Gangwon, Jeonnam, and Gyeongnam) had a relatively lower plaque reduction rate than the other locations. In addition, enzyme-linked immunosorbent assays were conducted to determine recent viral infections and 12 (2.2%) subjects were found to have been recently infected by the virus. In conclusion, the present study clearly indicated that the prevalence of neutralizing antibodies has been maintained at very high levels among adult age groups owing to vaccination or natural infections, or both. In the future, serosurveillance should be conducted periodically using more representative samples to better understand the population-level immunity to JE in South Korea. PMID:26807709

  20. Forecasting Japanese encephalitis incidence from historical morbidity patterns: Statistical analysis with 27 years of observation in Assam, India.

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    Handique, Bijoy K; Khan, Siraj A; Mahanta, J; Sudhakar, S

    2014-09-01

    Japanese encephalitis (JE) is one of the dreaded mosquito-borne viral diseases mostly prevalent in south Asian countries including India. Early warning of the disease in terms of disease intensity is crucial for taking adequate and appropriate intervention measures. The present study was carried out in Dibrugarh district in the state of Assam located in the northeastern region of India to assess the accuracy of selected forecasting methods based on historical morbidity patterns of JE incidence during the past 22 years (1985-2006). Four selected forecasting methods, viz. seasonal average (SA), seasonal adjustment with last three observations (SAT), modified method adjusting long-term and cyclic trend (MSAT), and autoregressive integrated moving average (ARIMA) have been employed to assess the accuracy of each of the forecasting methods. The forecasting methods were validated for five consecutive years from 2007-2012 and accuracy of each method has been assessed. The forecasting method utilising seasonal adjustment with long-term and cyclic trend emerged as best forecasting method among the four selected forecasting methods and outperformed the even statistically more advanced ARIMA method. Peak of the disease incidence could effectively be predicted with all the methods, but there are significant variations in magnitude of forecast errors among the selected methods. As expected, variation in forecasts at primary health centre (PHC) level is wide as compared to that of district level forecasts. The study showed that adopted forecasting techniques could reasonably forecast the intensity of JE cases at PHC level without considering the external variables. The results indicate that the understanding of long-term and cyclic trend of the disease intensity will improve the accuracy of the forecasts, but there is a need for making the forecast models more robust to explain sudden variation in the disease intensity with detail analysis of parasite and host population

  1. Entomological investigations into an epidemic of Japanese encephalitis (JE in northern districts of West Bengal, India (2011-2012

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    T Mariappan

    2014-01-01

    Full Text Available Background & objectives: Japanese encephalitis (JE is one of the most important arboviral diseases of human beings with outbreaks in many parts of Southeast Asia including India. We present the entomological findings of an outbreak occurred in northern part of West Bengal during 2011-2012 with special emphasis on the role of JE vectors in different seasons. Methods: Adult mosquito collections were made with the help of mouth aspirators, aided by flash lights during day time resting inside human and animal habitations as indoor, and resting outside field grasses, bushes, underneath of culverts and bridges as outdoor, and in and around the pig enclosures and cattle sheds during dusk period in JE affected villages from Cooch Behar, Dakshin Dinajpur, Darjeeling and Jalpaiguri districts in North West Bengal. In all study villages, a long handled with enamel bowl dipper was used to obtain immature stages of mosquitoes from various breeding habitats. Results: A total of 19 different types of mosquito breeding habitats were examined for vectors of JE. From these habitats, 23.7 per cent were positive for breeding during the study period. Overall, nine different species were recorded through emergence, but none was positive for JE virus when subjected for detection of virus. Adult mosquitoes of more than 50 per cent of the potential JE vector species obtained through dusk and the rest through indoor and outdoor collections in all seasons. Altogether, 27 different species were recorded. Most of these were JE vectors. Interpretation & conclusions: Our results showed that in addition to Cx. vishnui subgroup, detection of JE virus antigen in Cx. quinquefasciatus indicated the possible maintenance of JE virus in nature through poor vector mosquitoes throughout the year. Since, all potential vector species reported elsewhere in India were also found in this region and fluctuated in density in different seasons, a proper integrated vector control programme needs

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

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    Yi-Chin Fan

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

  3. Post-marketing safety surveillance for inactivated and live-attenuated Japanese encephalitis vaccines in China, 2008-2013.

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    Wu, Wendi; Liu, Dawei; Li, Keli; Nuorti, J Pekka; Nohynek, Hanna M; Xu, Disha; Ye, Jiakai; Zheng, Jingshan; Wang, Huaqing

    2017-06-22

    Two types of Japanese encephalitis (JE) vaccines, inactivated JE vaccine (JE-I) and live-attenuated JE vaccine (JE-L), are available and used in China. In particular, one JE-L, produced by a domestic manufacturer in China, was prequalified by WHO in 2013. We assessed the safety of JE vaccines in China during 2008-2013 using the Chinese National Adverse Events Following Immunization Information System (CNAEFIS) data. We retrieved AEFI reporting data about JE vaccines from CNAEFIS, 2008-2013, examined demographic characteristics of AEFI cases, and used administrative data on vaccine doses as denominator to calculate and compare crude reporting rates. We also used disproportionality reporting analysis between JE-I and JE-L to assess potential safety signals. A total of 34,879 AEFIs related with JE-I and JE-L were reported, with a ratio of male to female as 1.3:1; 361 (1.0%) cases were classified as serious. JE vaccines were administered concurrently with one or more other vaccines in 13,592 (39.0%) of cases. The overall AEFI reporting rates were 214.4 per million vaccination doses for JE-L and 176.9 for JE-I (rate ratio [RR]: 1.2, 95% confidence interval [CI]: 1.1-1.3) in 2010-2013. Febrile convulsions (FC) following JE-I was found as a signal of disproportionate reporting (SDR). However, there was no significant difference between the reporting rates of FC of JE-I and JE-L (0.3 per million vaccination doses for JE-L, 0.4 for JE-I, p=0.05). While our analysis did not find apparent safety concern of JE vaccines in China, further study should consider JE-I vaccines and febrile convulsion, and taking more sensitive methods to detect signals. Copyright © 2017. Published by Elsevier Ltd.

  4. Epidemiological trends and characteristics of Japanese encephalitis changed based on the vaccination program between 1960 and 2013 in Guangxi Zhuang Autonomous Region, southern China.

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    Yang, Yan; Liang, Nengxiu; Tan, Yi; Xie, Zhichun

    2016-04-01

    Japanese encephalitis (JE) is one of the most severe kinds of viral encephalitis and is prevalent in Asia and the Western Pacific. In China, JE was first reported in the 1940s and became the main cause of viral encephalitis, including in the Guangxi Zhuang Autonomous Region. In 1951, JE was included in the Chinese mandatory disease reporting system. In the pre-vaccine era of the 1960s and 1970s, the incidence of JE continued to rise without any vaccine supply. Since JE vaccines became available in the late 1970s (MBD) and 1989 (LAV-SA-14-14-2), and as JE vaccine became freely available to patients beginning in 2008, the incidence of JE has declined significantly. Despite these gains, outbreaks continue to occur among children in rural and suburban areas. Strengthening vaccine delivery models and improving swine vaccine production are important in order to sustain continuous declines in the incidence of JE in Guangxi. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. Antibodies are not required to a protective immune response against dengue virus elicited in a mouse encephalitis model.

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    Amorim, Jaime Henrique; dos Santos Alves, Rúbens Prince; Bizerra, Raíza; Araújo Pereira, Sara; Ramos Pereira, Lennon; Nascimento Fabris, Denicar Lina; Santos, Robert Andreata; Romano, Camila Malta; de Souza Ferreira, Luís Carlos

    2016-01-01

    Generating neutralizing antibodies have been considered a prerequisite to control dengue virus (DENV) infection. However, T lymphocytes have also been shown to be important in a protective immune state. In order to investigate the contribution of both humoral and cellular immune responses in DENV immunity, we used an experimental model in which a non-lethal DENV2 strain (ACS46) is used to intracranially prime Balb/C mice which develop protective immunity against a lethal DENV2 strain (JHA1). Primed mice generated envelope-specific antibodies and CD8(+) T cell responses targeting mainly non-structural proteins. Immune sera from protected mice did not confer passive protection to naïve mice challenged with the JHA1 strain. In contrast, depletion of CD4(+) and CD8(+) T lymphocytes significantly reduced survival of ACS46-primed mice challenged with the JHA1 strain. Collectively, results presented in this study show that a cellular immune response targeting non-structural proteins are a promising way in vaccine development against dengue.

  6. Japanese encephalitis (JE). Part I: clinical profile of 1,282 adult acute cases of four epidemics.

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    Sarkari, N B S; Thacker, A K; Barthwal, S P; Mishra, V K; Prapann, Shiv; Srivastava, Deepak; Sarkari, M

    2012-01-01

    Japanese encephalitis (JE) is numerically the most important global cause of encephalitis and so far confirmed to have caused major epidemics in India. Most of the reported studies have been in children. This largest study involving only adults, belonging to four epidemics, is being reported from Gorakhpur. The aim of this study is to detail the acute clinical profile (not viral) outcome and to classify the sequelae at discharge. This prospective study involved 1,282 adult patients initially diagnosed as JE admitted during the epidemics of 1978, 1980, 1988, and 1989, on identical clinical presentation and CSF examination. In the meantime, the diagnosis of JE was confirmed by serological and/or virological studies in only a representative number of samples (649 of 1,282 cases). Eighty-three left against medical advice (LAMA) at various stages, so 1,199 of 1,282 were available for the study. Peak incidence of [1,061 of 1,282 (83%)] of clinically suspected cases was from September 15 to November 2. Serum IgM and IgG were positive in high titers in 50.87% (330 of 649) and IgM positive in CSF in 88.75% (109 of 123) of the cases. JE virus could be isolated from CSF and brain tissue in 5 of 5 and 4 of 5 samples, respectively. Altered sensorium (AS) in (96%), convulsions (86%), and headache (85%) were the main symptoms for hospitalization by the third day of the onset. Other neurological features included hyperkinetic movements in 593 of 1,282 (46%)-choreoathetoid in 490 (83%) and bizarre, ill-defined in 103 (17%). The features of brain stem involvement consisted of opsoclonus (20%), gaze palsies (16%), and pupillary changes (48%) with waxing and waning character. Cerebellar signs were distinctly absent. Dystonia and decerebrate rigidity was observed in 43 and 6%, respectively, paralytic features in 17% and seizures in 30%. Many non-neurological features of prognostic importance included abnormal breathing patterns (ABP) (45%), pulmonary edema (PO) (33%), and upper

  7. 流行性乙型脑炎DNA疫苗研究新进展%New advances in research on DNA vaccine derived from Japanese encephalitis

    Institute of Scientific and Technical Information of China (English)

    冯国和; 窦晓光; 王玉梅; 周言

    2005-01-01

    流行性乙型脑炎(Japanese encephalitis,JE)疫苗防治问题是黄病毒领域主要研究内容之一.自1997年WHO提出以流行性乙型脑炎病毒(Japanese encephalitis virus,JEV)为研究目标,集中进行黄病毒多价疫苗研制与开发以来,JE DNA疫苗研究相继报道.虽然已证明了JE DNA疫苗在防治JEV感染方面的实验可行性,但是该类疫苗还不能像常规灭活或减毒活疫苗那样诱导强烈免疫应答.本文着重近3年来有关JE DNA疫苗免疫原性与增强效应等方面研究进展综述如下.

  8. Detection and differentiation of genotype I and III Japanese encephalitis virus in mosquitoes by multiplex reverse transcriptase-polymerase chain reaction.

    Science.gov (United States)

    Chen, Y Y; Lin, J W; Fan, Y C; Chiou, S S

    2014-02-01

    Japanese encephalitis (JE) is a disease that threatens both human and animal populations in Asian countries, and the causative agent of JE, Japanese encephalitis virus (JEV), has recently changed from genotype III (GIII) to genotype I (GI). However, a test for the rapid differentiation of GI and GIII JEV is still unavailable, especially one that can be used for mosquito-based surveillance. We have designed GI- and GIII-specific primer sets for the rapid detection and differentiation of GI and GIII JEV by multiplex reverse transcriptase-polymerase chain reaction (multiplex RT-PCR). The GI-specific and GIII-specific primer sets were able to specifically amplify the target gene from GI and GIII JEV, respectively. The limitations of detection were 0.00225 and 0.225 pfu for the GI-specific and GIII-specific primers, respectively. Using a mixture of GI-specific and GIII-specific primers, the multiplex RT-PCR was able to specifically detect and differentiate GI and GIII JEV. The multiplex RT-PCR was able to successfully differentiate GI and GIII virus in JEV-infected mosquitoes. Thus, a sensitive and specific multiplex RT-PCR system for the rapid detection and differentiation of GI and GIII JEV has been developed, and this test is likely to be valuable when carrying out mosquito-based JEV surveillance. © 2012 Blackwell Verlag GmbH.

  9. A Japanese encephalitis virus genotype 5 molecular clone is highly neuropathogenic in a mouse model: impact of the structural protein region on virulence.

    Science.gov (United States)

    de Wispelaere, Mélissanne; Frenkiel, Marie-Pascale; Desprès, Philippe

    2015-06-01

    Japanese encephalitis virus (JEV) strains can be separated into 5 genotypes (g1 to g5) based on sequence similarity. JEV g5 strains have been rarely isolated and are poorly characterized. We report here the full characterization of a g5 virus generated using a cDNA-based technology and its comparison with a widely studied g3 strain. We did not observe any major differences between those viruses when their infectious cycles were studied in various cell lines in vitro. Interestingly, the JEV g5 strain was highly pathogenic when inoculated to BALB/c mice, which are known to be largely resistant to JEV g3 infection. The study of chimeric viruses between JEV g3 and g5 showed that there was a poor viral clearance of viruses that express JEV g5 structural proteins in BALB/c mice blood, which correlated with viral invasion of the central nervous system and encephalitis. In addition, using an in vitro model of the blood-brain barrier, we were able to show that JEV g5 does not have an enhanced capacity for entering the central nervous system, compared to JEV g3. Overall, in addition to providing a first characterization of the understudied JEV g5, our work highlights the importance of sustaining an early viremia in the development of JEV encephalitis. Genotype 5 viruses are genetically and serologically distinct from other JEV genotypes and can been associated with human encephalitis, which warrants the need for their characterization. In this study, we characterized the in vitro and in vivo properties of a JEV g5 strain and showed that it was more neuropathogenic in a mouse model than a well-characterized JEV g3 strain. The enhanced virulence of JEV g5 was associated with poor viral clearance but not with enhanced crossing of the blood-brain barrier, thus providing new insights into JEV pathogenesis. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  10. 猪日本乙型脑炎检测技术研究进展%Progress of Detection Technology for the Swine Japanese Encephalitis B

    Institute of Scientific and Technical Information of China (English)

    赵凡凡; 游卫云; 王晓杜; 高利荣; 袁进强; 王婷; 周圻

    2011-01-01

    Japanese encephalitis B is a virus disease which can cause encephalitis of humans and domestic animal by Flavivir-us Japanese encephalitis virus (JEV) infected. All of human and many animals could be infected. The swine is the most important reservoir and sower. The diseases will cause reproductive disturbance of infected swine and the pig farm often suffered severe losses. So, the scientists attempted to find a faster and more accurate method to diagnose and detect JEV. This paper makes a brief summary of methods to detect JEV, such as isolation and identification of JEV, serological methods and methods in molecular biology.%猪日本乙型脑炎是由黄病毒科乙型脑炎病毒引起的一种人畜共患的病毒性传染病.人与多种动物均能感染,其中猪是主要的储存宿主和扩散宿主,猪感染该病毒后引发猪的繁殖障碍,使养猪业遭受重大经济损失,因此学者们一直在致力于寻找可以快速检测和诊断日本乙型脑炎的方法,为预防和治疗该病提供基础条件.文章对猪日本乙型脑炎检测技术,包括病毒分离鉴定方法、血清学方法、分子生物学方法等方面的研究进展进行了较为全面的综述.

  11. Rhombencephalitis associated with Dengue fever.

    Science.gov (United States)

    Verma, Rajesh; Bharti, Kavita; Mehta, Mannan; Bansod, Amrit

    2016-05-01

    Dengue infection is gradually disseminating throughout the world in alarming proportions. It is a arbovirus infection,transmitted by aedes mosquitoes. It is a multi-systemic disorder associated with varied neurological complications. There is increased trend of development of neurological complications in dengue fever. The neurological complications arising due to dengue infection can be categorized into central and neuromuscular complications. The central nervous system disorders reported with dengue fever are encephalopathy,encephalitis and myelitis.Here we report a case of rhombencephalitis associated with dengue fever. The literature does not mention rhombencephalitis occurring with dengue illness.

  12. Encefalitis por virus San Luis en la Ciudad de Buenos Aires durante el brote de dengue 2009 Saint Louis encephalitis virus in Buenos Aires city during the outbreak of dengue in 2009

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    Horacio López

    2011-06-01

    Full Text Available Se presenta un paciente de 80 años de edad, residente en la Ciudad de Buenos Aires, con diagnóstico serológico para el virus de la encefalitis de San Luis (SLE durante el brote de dengue ocurrido entre enero y mayo de 2009. Presentaba leucemia linfoide crónica en tratamiento con clorambucilo, cáncer de próstata tratado con hormonoterapia y radioterapia, e imágenes óseas compatibles con metástasis. El estudio del líquido cefalorraquídeo demostró pleocitosis con predominio de mononucleares y proteinorraquia elevada. El resultado de los cultivos para bacterias, hongos y micobacterias, así como el PCR en LCR para herpes virus, HSV, CMV y EBV, fue negativo. Se detectaron anticuerpos IgM para virus SLE tanto en LCR como en muestra de suero, con seroconversión IgG por neutralización en cultivos celulares y resultados negativos para los demás Flavivirus con circulación en Argentina. Se revisan evidencias sobre la presencia de virus de San Luis en nuestro país, y se señala la importancia de la confirmación diagnóstica y el estudio de otros Flavivirus en casos sospechosos de dengue con presentación grave o atípica. Este trabajo remarca la necesidad de fortalecer tanto la vigilancia epidemiológica del virus SLE, como el control vectorial para prevenir las diferentes infecciones transmitidas por mosquitos y conocer su efecto en Salud Pública en la Argentina.We report the case of a male, 80-year-old resident in the City of Buenos Aires, with a diagnosis of St. Louis encephalitis (SLE during a countrywide dengue outbreak, from January to May 2009. The patient had a chronic lymphocytic leukemia treated with chlorambucil, prostate cancer (hormone therapy and radiotherapy and images consistent with bone metastases. Cerebrospinal fluid examination showed pleocytosis with a predominance of mononuclear cells and high protein concentration. Bacteria, fungi and mycobacteria cultures, as well as the PCR for herpes virus, HSV, CMV and EBV, were

  13. Distinct dictation of Japanese encephalitis virus-induced neuroinflammation and lethality via triggering TLR3 and TLR4 signal pathways.

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    Young Woo Han

    2014-09-01

    Full Text Available Japanese encephalitis (JE is major emerging neurologic disease caused by JE virus. To date, the impact of TLR molecules on JE progression has not been addressed. Here, we determined whether each TLR modulates JE, using several TLR-deficient mouse strains (TLR2, TLR3, TLR4, TLR7, TLR9. Surprisingly, among the tested TLR-deficient mice there were contrasting results in TLR3(-/- and TLR4(-/- mice, i.e. TLR3(-/- mice were highly susceptible to JE, whereas TLR4(-/- mice showed enhanced resistance to JE. TLR3 ablation induced severe CNS inflammation characterized by early infiltration of inflammatory CD11b(+Ly-6Chigh monocytes along with profoundly increased viral burden, proinflammatory cytokine/chemokine expression as well as BBB permeability. In contrast, TLR4(-/- mice showed mild CNS inflammation manifested by reduced viral burden, leukocyte infiltration and proinflammatory cytokine expression. Interestingly, TLR4 ablation provided potent in vivo systemic type I IFN innate response, as well as ex vivo type I IFN production associated with strong induction of antiviral PRRs (RIG-I, MDA5, transcription factors (IRF-3, IRF-7, and IFN-dependent (PKR, Oas1, Mx and independent ISGs (ISG49, ISG54, ISG56 by alternative activation of IRF3 and NF-κB in myeloid-derived DCs and macrophages, as compared to TLR3(-/- myeloid-derived cells which were more permissive to viral replication through impaired type I IFN innate response. TLR4 ablation also appeared to mount an enhanced type I IFN innate and humoral, CD4(+ and CD8(+ T cell responses, which were mediated by altered immune cell populations (increased number of plasmacytoid DCs and NK cells, reduced CD11b(+Ly-6C(high monocytes and CD4(+Foxp3(+ Treg number in lymphoid tissue. Thus, potent type I IFN innate and adaptive immune responses in the absence of TLR4 were closely coupled with reduced JE lethality. Collectively, these results suggest that a balanced triggering of TLR signal array by viral components

  14. Study on persistent infection of Japanese encephalitis virus Beijing-1 strain in serum-free Sf9 cell cultures.

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    Kim, Hun; Lee, Su Jeen; Park, Jin Yong; Park, Yong Wook; Kim, Hyun Sung; Kang, Heui-Yun; Hur, Byung-Ki; Ryu, Yeon-Woo; Han, Sang In; Kim, Jong Su

    2004-03-01

    Sf9 cells have obvious advantages for the conventional production technology of vaccine. They are useful tools for high concentration and large-scale cultures. Sf9 cells were grown to maximal concentration, 8 x 10(6) cells/ml in a 500ml spinner flask, with a doubling time at the exponentially growing phase of 24.5 hours, using serum-free media. To explore the ability of Sf9 cells to be infected by the Japanese encephalitis (JE) virus Beijing-1 strain, Sf9 cells were infected with the virus. By 4-5 days post-infection, 10-15% of the Sf9 cells showed cytopathic effect (CPE), from granularity to the formation of syncytia and multinucleated giant cells continuously observed over a period of 35 days. Positive fluorescent reactions were detected in 30-40% of cells infected with the JE virus Beijing-1 strain, and the uninfected Sf9 cells were completely negative. Virus particles, propagated in Sf9 and Vero cells, were concentrated by sedimentation on 40% trehalose cushions by ultracentrifugation, and showed identical patterns of viral morphogenesis. Complete virus particles, 40 to 50 nm in diameter, were observed, and JE virus envelope (E) proteins, at 53 kDa, were found in the western blot analysis to the anti-JE virus E protein monoclonal antibody and reacted as a magenta band in the same position to the glycoprotein staining. To evaluate whether the infectious virus was produced in Sf9 cells inoculated with the JE virus Beijing-1 stain, Sf9 cells were inoculated with the virus, and sample harvested every 5 days. The titers of the JE virus Beijing-1 strain rose from 1.0 x 10(5) to 1.5 x 10(6) pfu/ml. The infected Sf9 cells could be sub-cultured in serum-free medium, with no change in the plaque sizes formed by the JE virus Beijing-1 strain in the plaque assay. It is suggested that the ability of the JE virus Beijing-1 strain to infect Sf9 cells in serum-free media will provide a useful insect cell system, where the JE virus replication, cytopathogenicity and vaccine

  15. Forty Years of Dengue Surveillance at a Tertiary Pediatric Hospital in Bangkok, Thailand, 1973-2012.

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    Nisalak, Ananda; Clapham, Hannah E; Kalayanarooj, Siripen; Klungthong, Chonticha; Thaisomboonsuk, Butsaya; Fernandez, Stefan; Reiser, Julia; Srikiatkhachorn, Anon; Macareo, Louis R; Lessler, Justin T; Cummings, Derek A T; Yoon, In-Kyu

    2016-06-01

    Long-term observational studies can provide valuable insights into overall dengue epidemiology. Here, we present analysis of dengue cases at a pediatric hospital in Bangkok, Thailand, during a 40-year period from 1973 to 2012. Data were analyzed from 25,715 hospitalized patients with laboratory-confirmed dengue virus (DENV) infection. Several long-term trends in dengue disease were identified including an increase in mean age of hospitalized cases from an average of 7-8 years, an increase after 1990 in the proportion of post-primary cases for DENV-1 and DENV-3, and a decrease in the proportion of dengue hemorrhagic fever and dengue shock syndrome cases in primary and post-primary cases over time. Exploratory mechanistic analysis of these observed trends considered changes in diagnostic methods, demography, force of infection, and Japanese encephalitis vaccination as possible explanations. Thailand is an important setting for studying DENV transmission as it has a "mature" dengue epidemiology with a strong surveillance system in place since the early 1970s. We characterized changes in dengue epidemiology over four decades, and possible impact of demographic and other changes in the human population. These results may inform other countries where similar changes in transmission and population demographics may now or may soon be occurring.

  16. [A Case of Dengue Fever and Subsequent Long-lasting Depression Accompanied by Alopecia in a Japanese Traveler Returning from Bali, Indonesia].

    Science.gov (United States)

    Hitani, Akihiro; Yamaya, Waka; To, Masako; Kano, Ichino; Honda-Hosono, Natsue; Takasaki, Tomohiko; Haruki, Kosuke

    2015-03-01

    Recovery from dengue fever is generally rapid and uneventful. However, recuperation is often prolonged and may be accompanied by noticeable depression. We present herein on a traveler to Indonesia who developed long-lasting depression after the classic symptoms of dengue fever such as fever, arthralgia, and macropapular rash had resolved. A previously healthy 42-year old japanese woman presented to the Travel Clinic of Seirei Yokohama Hospital with complaints of 4 days of fever, joint aches, bone pain, and a macropapular rash on her torso. She had returned from Bali 5 days previously. During her 1-week stay, one day was spent in rural, mountainous areas where she was exposed to several mosquito bites. The 1st serum sample collected 4 days after the disease onset gave positive result in the rapid dengue IgM antibody test and the rapid dengue NS1 antigen immunechromatographic test. The DENV-1 genome was detected with RT-PCR. Her 13-year old son, who had accompanied her, was also diagnosed as having dengue fever and he recovered without event. The Above-mentioned symptoms resolved within one week. However, the patient suffered from prolonged depression. She also noticed loss of hair 3 months after the disease onset Administration of a Serotonin-Noradrenalin Reuptake Inhibitor and a minor tranquillizer required to allow her requied to lead a normal life. Although she gradually felt better, it took approximately 2 years until she had recovered completely without taking any antidepressant and minor tranquillizer. It is a well-known fact in endemic countries that dengue fever could have an significant impact on the patients' mental well-being. However, it appears that physicians in non-endemic countries are not fully aware of the prolonged depression, which can occur subsequent to the acute illness. Follow-up consultations of returing travelers who have recoverd from dengu fever should be arranged to monitor their mental and emotional states closely.

  17. Travelers' Health: Japanese Encephalitis

    Science.gov (United States)

    ... Andhra Pradesh, Assam, Bihar, Goa, Haryana, Karnataka, Kerala, Tamil Nadu, Uttar Pradesh, and West Bengal Indonesia Presumed ... human cases in north, central, and southern Laos Malaysia Endemic in Sarawak; sporadic cases reported from all ...

  18. Ablation of CD11c(hi) dendritic cells exacerbates Japanese encephalitis by regulating blood-brain barrier permeability and altering tight junction/adhesion molecules.

    Science.gov (United States)

    Kim, Jin Hyoung; Hossain, Ferdaus Mohd Altaf; Patil, Ajit Mahadev; Choi, Jin Young; Kim, Seong Bum; Uyangaa, Erdenebelig; Park, Sang-Youel; Lee, John-Hwa; Kim, Bumseok; Kim, Koanhoi; Eo, Seong Kug

    2016-10-01

    Japanese encephalitis (JE), characterized by extensive neuroinflammation following infection with neurotropic JE virus (JEV), is becoming a leading cause of viral encephalitis due to rapid changes in climate and demography. The blood-brain barrier (BBB) plays an important role in restricting neuroinvasion of peripheral leukocytes and virus, thereby regulating the progression of viral encephalitis. In this study, we explored the role of CD11c(hi) dendritic cells (DCs) in regulating BBB integrity and JE progression using a conditional depletion model of CD11c(hi) DCs. Transient ablation of CD11c(hi) DCs resulted in markedly increased susceptibility to JE progression along with highly increased neuro-invasion of JEV. In addition, exacerbated JE progression in CD11c(hi) DC-ablated hosts was closely associated with increased expression of proinflammatory cytokines (IFN-β, IL-6, and TNF-α) and CC chemokines (CCL2, CCL3, CXCL2) in the brain. Moreover, our results revealed that the exacerbation of JE progression in CD11c(hi) DC-ablated hosts was correlated with enhanced BBB permeability and reduced expression of tight junction and adhesion molecules (claudin-5, ZO-1, occluding, JAMs). Ultimately, our data conclude that the ablation of CD11c(hi) DCs provided a subsidiary impact on BBB integrity and the expression of tight junction/adhesion molecules, thereby leading to exacerbated JE progression. These findings provide insight into the secondary role of CD11c(hi) DCs in JE progression through regulation of BBB integrity and the expression of tight junction/adhesion molecules.

  19. Genetic Determinants of Japanese Encephalitis Virus Vaccine Strain SA14-14-2 That Govern Attenuation of Virulence in Mice.

    Science.gov (United States)

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

    2015-06-01

    The safety and efficacy of the live-attenuated Japanese encephalitis virus (JEV) SA14-14-2 vaccine are attributed to mutations that accumulated in the viral genome during its derivation. However, little is known about the contribution that is made by most of these mutations to virulence attenuation and vaccine immunogenicity. Here, we generated recombinant JEV (rJEV) strains containing JEV SA14-14-2 vaccine-specific mutations that are located in the untranslated regions (UTRs) and seven protein genes or are introduced from PCR-amplified regions of the JEV SA14-14-2 genome. The resulting mutant viruses were evaluated in tissue culture and in mice. The authentic JEV SA14-14-2 (E) protein, with amino acid substitutions L107F, E138K, I176V, T177A, E244G, Q264H, K279M, A315V, S366A, and K439R relative to the wild-type rJEV clone, was essential and sufficient for complete attenuation of neurovirulence. Individually, the nucleotide substitution T39A in the 5' UTR (5'-UTR-T39A), the capsid (C) protein amino acid substitution L66S (C-L66S), and the complete NS1/2A genome region containing 10 mutations each significantly reduced virus neuroinvasion but not neurovirulence. The levels of peripheral virulence attenuation imposed by the 5'-UTR-T39A and C-L66S mutations, individually, were somewhat mitigated in combination with other vaccine strain-specific mutations, which might be compensatory, and together did not affect immunogenicity. However, a marked reduction in immunogenicity was observed with the addition of the NS1/2A and NS5 vaccine virus genome regions. These results suggest that a second-generation recombinant vaccine can be rationally engineered to maximize levels of immunogenicity without compromising safety. The live-attenuated JEV SA14-14-2 vaccine has been vital for controlling the incidence of disease caused by JEV, particularly in rural areas of Asia where it is endemic. The vaccine was developed >25 years ago by passaging wild-type JEV strain SA14 in tissue

  20. A conserved predicted pseudoknot in the NS2A-encoding sequence of West Nile and Japanese encephalitis flaviviruses suggests NS1' may derive from ribosomal frameshifting

    Directory of Open Access Journals (Sweden)

    Atkins John F

    2009-02-01

    Full Text Available Abstract Japanese encephalitis, West Nile, Usutu and Murray Valley encephalitis viruses form a tight subgroup within the larger Flavivirus genus. These viruses utilize a single-polyprotein expression strategy, resulting in ~10 mature proteins. Plotting the conservation at synonymous sites along the polyprotein coding sequence reveals strong conservation peaks at the very 5' end of the coding sequence, and also at the 5' end of the sequence encoding the NS2A protein. Such peaks are generally indicative of functionally important non-coding sequence elements. The second peak corresponds to a predicted stable pseudoknot structure whose biological importance is supported by compensatory mutations that preserve the structure. The pseudoknot is preceded by a conserved slippery heptanucleotide (Y CCU UUU, thus forming a classical stimulatory motif for -1 ribosomal frameshifting. We hypothesize, therefore, that the functional importance of the pseudoknot is to stimulate a portion of ribosomes to shift -1 nt into a short (45 codon, conserved, overlapping open reading frame, termed foo. Since cleavage at the NS1-NS2A boundary is known to require synthesis of NS2A in cis, the resulting transframe fusion protein is predicted to be NS1-NS2AN-term-FOO. We hypothesize that this may explain the origin of the previously identified NS1 'extension' protein in JEV-group flaviviruses, known as NS1'.

  1. Rapid and simple detection of Japanese encephalitis virus by reverse transcription loop-mediated isothermal amplification combined with a lateral flow dipstick.

    Science.gov (United States)

    Deng, Jieru; Pei, Jingjing; Gou, Hongchao; Ye, Zuodong; Liu, Cuicui; Chen, Jinding

    2015-03-01

    Japanese encephalitis virus (JEV) is a major cause of viral encephalitis in geographical areas, such as Asia and Western Pacific, where it is a threat to human and animal health. To control this disease, it is necessary to develop a rapid, simple, accurate method for diagnosis. In this study, a method based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) coupled with a lateral flow dipstick (LFD) has been developed to detect JEV (JEV RT-LAMP-LFD). The entire assay can be completed within 70 min, and in this study, no false positive results were observed when other pathogens were tested, indicating that the assay is a highly specific method for the detection of JEV. Additionally, the sensitivity of the RT-LAMP-LFD assay for SA14-14-2 strain was 50 pg of RNA, which was similar to that of RT-PCR and RT-LAMP combined with gel electrophoresis, and was 10-fold more sensitive than RT-LAMP combined with calcein. The limit of detection for this assay was 5 pg of RNA. In addition, no false positive results were obtained with 14 serum samples. Our results indicate that this RT-LAMP-LFD assay will be of great value for JEV infection testing due to its rapid and highly specific and sensitive properties. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Comparison of the genome sequences and the phylogenetic analyses of the GP78 and the Vellore P20778 isolates of Japanese encephalitis virus from India

    Indian Academy of Sciences (India)

    Sudhanshu Vrati

    2000-09-01

    The nucleotide sequence of the complete genomes of two Indian isolates of Japanese encephalitis virus were compared. One of these isolates, GP78 was obtained from northern India in 1978. The other, the Vellore P20778 isolate, was obtained from southern India in 1958. There was 4.40% nucleotide sequence divergence between the two Indian isolates that resulted in a 1.86% amino acid sequence divergence. Phylogenetic analyses showed that in evolutionary terms the north Indian GP78 isolate was close to the SA14 isolate from China whereas the south Indian Vellore P20778 isolate was close to the Beijing-1 isolate, also from China. The two Indian isolates, however, appear to have evolved independently.

  3. WHO working group on the quality, safety and efficacy of japanese encephalitis vaccines (live attenuated) for human use, Bangkok, Thailand, 21-23 February 2012.

    Science.gov (United States)

    Trent, Dennis W; Minor, Philip; Jivapaisarnpong, Teeranart; Shin, Jinho

    2013-11-01

    Japanese encephalitis (JE) is one of the most important viral encephalitides in Asia. Two live-attenuated vaccines have been developed and licensed for use in countries in the region. Given the advancement of immunization of humans with increasing use of live-attenuated vaccines to prevent JE, there is increased interest to define quality standards for their manufacture, testing, nonclinical studies, and clinical studies to assess their efficacy and safety in humans. To this end, WHO convened a meeting with a group of international experts in February 2012 to develop guidelines for evaluating the quality, safety and efficacy of live-attenuated JE virus vaccines for prevention of human disease. This report summarizes collective views of the participants on scientific and technical issues that need to be considered in the guidelines. Copyright © 2013. Published by Elsevier Ltd.. All rights reserved.

  4. WHO informal consultation on the scientific basis of specifications for production and control of inactivated Japanese encephalitis vaccines for human use, Geneva, Switzerland, 1-2 June 2006.

    Science.gov (United States)

    Ferguson, Morag; Kurane, Ichiro; Wimalaratne, Omala; Shin, Jinho; Wood, David

    2007-07-20

    The World Health Organization (WHO) publishes technical guidance on the quality, safety and efficacy of vaccines intended to assist national regulatory authorities and manufacturers. As part of its programme, WHO convened an informal consultation to initiate revision of the WHO recommendations on the production and control of inactivated Japanese encephalitis (JE) vaccines for human use, at its headquarters in June 2006. The attendees included experts from national regulatory authorities, national control laboratories and manufacturers from around the world as per WHO policy to include all relevant stakeholders in the standards development process. Issues pertaining to recent development with inactivated JE vaccines were presented and discussed. Participants agreed upon the scientific basis of revised specifications and the inclusion of new sections on nonclinical and clinical evaluation of inactivated JE vaccines. It was agreed that the revision would cover both existing vaccines derived from mouse brain or primary cell cultures and vaccines under development in a continuous cell line (Vero).

  5. 贵州猪乙型脑炎血清流行病学的调查%Serological Investigation on Swine Japanese Encephalitis in Guizhou

    Institute of Scientific and Technical Information of China (English)

    华莹; 李基棕

    2012-01-01

    为了解贵州省规模养猪场乙型脑炎(JE)的流行情况,为该病的诊断、预防和控制提供参考,应用乳胶凝集试验(LAT)对9个地区216个规模养猪场的2 906份血清进行检测.结果表明:查出阳性血清1 239份,占受检血清的42.6%,以黔南州(74.9%)和贵阳市(66.7%)的血清阳性率较高;133个猪场检测出阳性血清,阳性场率为61.6%,以贵阳市(92.3%)和遵义市(93.5%)的猪场阳性率较高.结论:贵州省猪群存在JE感染,且感染率较高,应采取积极的防治措施.%To grasp the infected situation of swine Japanese encephalitis (JE) in Guizhou, 2 906 serum samples were collected from 216 large-scale pig farms in nine areas for detection of Japanese encephalitis virus (JEV) antibodies using latex agglutination test (LAT). The results showed that 1239 serum samples were positive, accounting for 42. 6%. The high JE infection rate (74. 9%, 66. 7%) in swine was recorded in Guiyang and Qiannan. The positive rate of large-scale pig farms was 61. 6%, and Guiyang (92. 3%)and Zunyi(93. 5%) were the highest. Therefore, swine JE infection in Guizhou was widespread, active countermeasures should be taken to prevent and cure swine JE.

  6. Interaction between Japanese encephalitis virus proteins and host proteins%日本脑炎病毒蛋白与宿主蛋白的相互作用

    Institute of Scientific and Technical Information of China (English)

    丁德平; 冯国和

    2011-01-01

    Japanese encephalitis virus(JEV) belongs to flaviviridae family, it can causes Japanese encephalitis which is mosquito-borne zoonotic diseases. The disease mainly referes to central nervous system with high mortality. Because its pathogenesis has not been fully defined, there is no specific treatment for it. Recent researches suggest that the interaction between JEV proteins and host proteins has very important influence on the virus replication, neurovirulence, neuronal proliferation/apoptosis, interferon resistance and induces protective immunity. The progress in molecular mechanisms for the interaction between JEV proteins and host proteins from the aspects of JEV genomic structure, structure proteins, nonstructural proteins and their function are described in the article.%日本脑炎病毒(JEV)隶属于黄病毒科黄病毒属,所致的日本脑炎为经蚊虫传播的人畜共患疾病,主要累及中枢神经系统,病死率高,因其致病机制复杂,至今尚无特异治疗方法.近年研究表明,JEV蛋白与宿主细胞蛋白的相互作用对病毒复制、嗜神经毒力、神经细胞增殖/凋亡、IFN抵抗及诱导宿主保护性免疫等方面可产生重要影响.此文重点从JEV基因结构、病毒结构和非结构蛋白及其功能等层面,对JEV主要编码蛋白与宿主细胞蛋白相互作用与影响作了综述.

  7. A study of glutamate levels, NR1, NR2A, NR2B receptors and oxidative stress in rat model of Japanese encephalitis.

    Science.gov (United States)

    Chauhan, Prashant Singh; Misra, Usha Kant; Kalita, Jayantee

    2017-03-15

    There is paucity of studies on the role of glutamate excitotoxicity in cell damage in Japanese encephalitis. In this study the glutamate levels and its NMDA receptors, and oxidative stress markers in different brain regions have been evaluated and correlated with neurobehavioral changes at different time points. Twelve day old Wistar rats were inoculated with 3×10(6)pfu/ml intracerebrally. The neurobehavioral effects were evaluated by spontaneous locomotor activity (SLA), grip strength and rota rod test on 10, 33 and 48days post inoculation (dpi). Glutamate level was evaluated by enzyme linked immunosorbent assay, mRNA gene expression of ionotropic glutamate receptors N-methyl d-aspartate (NMDA) receptor 1, 2A and 2B (NR1, NR2A and NR2B) were evaluated by real time PCR. Malondialdehyde (MDA), glutathione (GSH) and glutathione peroxidase (GPx) levels were measured by spectrophotometer in different brain regions of JEV infected rats on 10, 33 and 48dpi. There was significant increase in motor deficit, grip strength and decreased locomotor activity on 10 and 33dpi. Glutamate levels were increased in thalamus, midbrain, frontal cortex, striatum and cerebellum on 10 and 33dpi and were followed by a recovery on 48dpi. Glutamate NMDR receptors NR1, NR2A and NR2B were reduced in thalamus, midbrain, frontal cortex, striatum and cerebellum on 10dpi which was followed by recovery after 33dpi. A significant increase in MDA level in thalamus, midbrain, frontal cortex, striatum and cerebellum was noted on 10 and 33dpi. The antioxidant GSH and GPx were significantly reduced in these brain regions on 10 and 33dpi. Glutamate, MDA, GSH and GPx correlated in different brain regions as the disease progress. Increased Glutamate level may be related to oxidative stress and may be responsible for behavioral alterations in rat model of Japanese encephalitis. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Safety of the Inactivated Japanese Encephalitis Virus Vaccine IXIARO in Children: An Open-label, Randomized, Active-controlled, Phase 3 Study.

    Science.gov (United States)

    Dubischar, Katrin L; Kadlecek, Vera; Sablan, Benjamin; Borja-Tabora, Charissa Fay; Gatchalian, Salvacion; Eder-Lingelbach, Susanne; Mueller, Zsuzsanna; Westritschnig, Kerstin

    2017-09-01

    Japanese encephalitis remains a serious health concern in Asian countries and has sporadically affected pediatric travelers. In the present study, we monitored the safety profile of the Japanese encephalitis virus vaccine IXIARO (Valneva Austria GmbH, Vienna, Austria) in a pediatric population. We randomized 1869 children between 2 months and 17 years of age in an age-stratified manner to vaccination with IXIARO or one of the control vaccines, Prevnar (formerly Wyeth Pharmaceuticals Inc., now Pfizer Inc., Kent, United Kingdom) and HAVRIX 720 (GlaxoSmithKline Biologicals, Rixensart, Belgium). Adverse events (AEs) (unsolicited and solicited local and systemic AEs), serious AEs and medically attended AEs were assessed up to day 56 and month 7 after the first dose. Incidences of AEs, serious AEs or medically attended AEs did not differ significantly between the groups in any age stratum. AEs were most frequent in children <1 year of age and decreased with age. AEs of special interest, predefined as AEs associated with potential hypersensitivity/allergy or neurologic disorders up to day 56, were reported in 4.6% (IXIARO) versus 6.3% (Prevnar) in the ≥2 months to <1 year age group and 3.4% (IXIARO) versus 3.3% (HAVRIX) in the ≥1 to <18 years age group. Fever, the most frequent systemic reaction in 23.7% of infants to 3.8% of adolescents, decreased with age and did not differ between groups. The safety profile of IXIARO was comparable to the control vaccines in terms of overall AE rates, serious AEs and medically attended AEs.

  9. Blockage of indoleamine 2,3-dioxygenase regulates Japanese encephalitis via enhancement of type I/II IFN innate and adaptive T-cell responses.

    Science.gov (United States)

    Kim, Seong Bum; Choi, Jin Young; Uyangaa, Erdenebileg; Patil, Ajit Mahadev; Hossain, Ferdaus Mohd Altaf; Hur, Jin; Park, Sang-Youel; Lee, John-Hwa; Kim, Koanhoi; Eo, Seong Kug

    2016-04-18

    Japanese encephalitis (JE), a leading cause of viral encephalitis, is characterized by extensive neuroinflammation following infection with neurotropic JE virus (JEV). Indoleamine 2,3-dioxygenase (IDO) has been identified as an enzyme associated with immunoregulatory function. Although the regulatory role of IDO in viral replication has been postulated, the in vivo role of IDO activity has not been fully addressed in neurotropic virus-caused encephalitis. Mice in which IDO activity was inhibited by genetic ablation or using a specific inhibitor were examined for mortality and clinical signs after infection. Neuroinflammation was evaluated by central nervous system (CNS) infiltration of leukocytes and cytokine expression. IDO expression, viral burden, JEV-specific T-cell, and type I/II interferon (IFN-I/II) innate responses were also analyzed. Elevated expression of IDO activity in myeloid and neuron cells of the lymphoid and CNS tissues was closely associated with clinical signs of JE. Furthermore, inhibition of IDO activity enhanced resistance to JE, reduced the viral burden in lymphoid and CNS tissues, and resulted in early and increased CNS infiltration by Ly-6C(hi) monocytes, NK, CD4(+), and CD8(+) T-cells. JE amelioration in IDO-ablated mice was also associated with enhanced NK and JEV-specific T-cell responses. More interestingly, IDO ablation induced rapid enhancement of type I IFN (IFN-I) innate responses in CD11c(+) dendritic cells (DCs), including conventional and plasmacytoid DCs, following JEV infection. This enhanced IFN-I innate response in IDO-ablated CD11c(+) DCs was coupled with strong induction of PRRs (RIG-I, MDA5), transcription factors (IRF7, STAT1), and antiviral ISG genes (Mx1, Mx2, ISG49, ISG54, ISG56). IDO ablation also enhanced the IFN-I innate response in neuron cells, which may delay the spread of virus in the CNS. Finally, we identified that IDO ablation in myeloid cells derived from hematopoietic stem cells (HSCs) dominantly

  10. Functionality of Dengue Virus Specific Memory T Cell Responses in Individuals Who Were Hospitalized or Who Had Mild or Subclinical Dengue Infection

    Science.gov (United States)

    Jeewandara, Chandima; Adikari, Thiruni N.; Gomes, Laksiri; Fernando, Samitha; Fernando, R. H.; Perera, M. K. T.; Ariyaratne, Dinuka; Kamaladasa, Achala; Salimi, Maryam; Prathapan, Shamini

    2015-01-01

    Background Although antibody responses to dengue virus (DENV) in naturally infected individuals have been extensively studied, the functionality of DENV specific memory T cell responses in relation to clinical disease severity is incompletely understood. Methodology/Principal findings Using ex vivo IFNγ ELISpot assays, and by determining cytokines produced in ELISpot supernatants, we investigated the functionality of DENV-specific memory T cell responses in a large cohort of individuals from Sri Lanka (n=338), who were naturally infected and were either hospitalized due to dengue or had mild or sub clinical dengue infection. We found that T cells of individuals with both past mild or sub clinical dengue infection and who were hospitalized produced multiple cytokines when stimulated with DENV-NS3 peptides. However, while DENV-NS3 specific T cells of those with mild/sub clinical dengue infection were more likely to produce only granzyme B (p=0.02), those who were hospitalized were more likely to produce both TNFα and IFNγ (p=0.03) or TNFα alone. We have also investigated the usefulness of a novel T cell based assay, which can be used to determine the past infecting DENV serotype. 92.4% of DENV seropositive individuals responded to at least one DENV serotype of this assay and none of the seronegatives responded. Individuals who were seronegative, but had received the Japanese encephalitis vaccine too made no responses, suggesting that the peptides used in this assay did not cross react with the Japanese encephalitis virus. Conclusions/significance The types of cytokines produced by DENV-specific memory T cells appear to influence the outcome of clinical disease severity. The novel T cell based assay, is likely to be useful in determining the past infecting DENV serotype in immune-epidemiological studies and also in dengue vaccine trials. PMID:25875020

  11. Functionality of dengue virus specific memory T cell responses in individuals who were hospitalized or who had mild or subclinical dengue infection.

    Directory of Open Access Journals (Sweden)

    Chandima Jeewandara

    2015-04-01

    Full Text Available Although antibody responses to dengue virus (DENV in naturally infected individuals have been extensively studied, the functionality of DENV specific memory T cell responses in relation to clinical disease severity is incompletely understood.Using ex vivo IFNγ ELISpot assays, and by determining cytokines produced in ELISpot supernatants, we investigated the functionality of DENV-specific memory T cell responses in a large cohort of individuals from Sri Lanka (n=338, who were naturally infected and were either hospitalized due to dengue or had mild or sub clinical dengue infection. We found that T cells of individuals with both past mild or sub clinical dengue infection and who were hospitalized produced multiple cytokines when stimulated with DENV-NS3 peptides. However, while DENV-NS3 specific T cells of those with mild/sub clinical dengue infection were more likely to produce only granzyme B (p=0.02, those who were hospitalized were more likely to produce both TNFα and IFNγ (p=0.03 or TNFα alone. We have also investigated the usefulness of a novel T cell based assay, which can be used to determine the past infecting DENV serotype. 92.4% of DENV seropositive individuals responded to at least one DENV serotype of this assay and none of the seronegatives responded. Individuals who were seronegative, but had received the Japanese encephalitis vaccine too made no responses, suggesting that the peptides used in this assay did not cross react with the Japanese encephalitis virus.The types of cytokines produced by DENV-specific memory T cells appear to influence the outcome of clinical disease severity. The novel T cell based assay, is likely to be useful in determining the past infecting DENV serotype in immune-epidemiological studies and also in dengue vaccine trials.

  12. A novel indirect ELISA for diagnosis of dengue fever.

    Science.gov (United States)

    Narayan, Rohan; Raja, Senthil; Kumar, Senthil; Sambasivam, Mohana; Jagadeesan, Raja; Arunagiri, Kavita; Krishnasamy, Kaveri; Palani, Gunasekaran

    2016-07-01

    Dengue fever (DF) is associated with significant morbidity and mortality in the tropical and sub-tropical regions of the world. Since there are no effective antiviral drugs for treatment, clinicians often rely on the accurate diagnosis of dengue fever to begin supportive therapy at early stages of the illness. The objective of this study was to develop an in-house dengue virus serotype 2 (DENV-2) non-structural protein- 5 (NS5) based indirect ELISA. DENV-2 was raised in Vero cells and the viral proteins were separated and subsequently the NS5 protein was eluted. Serum samples from primary and secondary dengue fever patients; and acute and convalescent samples from Japanese encephalitis (JE) and West Nile virus (WNV) cases were used to validate the ELISA. The assay was found to be 100 per cent specific in detecting DENV-2 specific antibodies from patient's serum. However, in terms of sensitivity, the assay could detect IgM antibodies only from 90 per cent of the primary dengue samples. The IgM/IgG ratio of the primary and secondary samples was 7.24 and 0.64, respectively. The results indicate that the DENV-2 NS5 ELISA is dengue group specific and can be used to differentiate dengue infection from other circulating Flavivirus infections. This NS5 ELISA can also be used to distinguish between primary and secondary dengue fever on the basis of IgM/IgG ratios. Further studies with larger sample sizes and different DENV serotypes are required to validate the ELISA.

  13. A novel indirect ELISA for diagnosis of dengue fever

    Directory of Open Access Journals (Sweden)

    Rohan Narayan

    2016-01-01

    Full Text Available Background & objectives: Dengue fever (DF is associated with significant morbidity and mortality in the tropical and sub-tropical regions of the world. Since there are no effective antiviral drugs for treatment, clinicians often rely on the accurate diagnosis of dengue fever to begin supportive therapy at early stages of the illness. The objective of this study was to develop an in-house dengue virus serotype 2 (DENV-2 non-structural protein- 5 (NS5 based indirect ELISA. Methods: DENV-2 was raised in Vero cells and the viral proteins were separated and subsequently the NS5 protein was eluted. Serum samples from primary and secondary dengue fever patients; and acute and convalescent samples from Japanese encephalitis (JE and West Nile virus (WNV cases were used to validate the ELISA. Results: The assay was found to be 100 per cent specific in detecting DENV-2 specific antibodies from patient′s serum. However, in terms of sensitivity, the assay could detect IgM antibodies only from 90 per cent of the primary dengue samples. The IgM/IgG ratio of the primary and secondary samples was 7.24 and 0.64, respectively. Interpretation & conclusions: The results indicate that the DENV-2 NS5 ELISA is dengue group specific and can be used to differentiate dengue infection from other circulating Flavivirus infections. This NS5 ELISA can also be used to distinguish between primary and secondary dengue fever on the basis of IgM/IgG ratios. Further studies with larger sample sizes and different DENV serotypes are required to validate the ELISA.

  14. Dengue Dengue

    Directory of Open Access Journals (Sweden)

    Eric Martínez Torres

    2008-12-01

    Full Text Available El dengue es hoy la más importante arbovirosis, por su gran carga de enfermedad e implicaciones sociales. El mosquito Aedes aegypti, su principal transmisor convive con el hombre en su hábitat domestico y peridoméstico. El cuadro clínico es de fiebre, cefalea, dolor retroocular, dolores corporales, exantema y mucho decaimiento. El enfermo puede empeorar súbitamente y presentar choque por dengue, con grandes hemorragias digestivas y elevada mortalidad. No existe droga antiviral, pero la muerte puede evitarse mediante la infusión intravenosa precoz de soluciones cristaloides. Algunos candidatos vacunales están actualmente en ensayo clínico. La prevención depende del control del vector, mediante educación sanitaria y reordenamiento ambiental.Dengue is the most important arbovirosis in the World, with a huge burden of disease and social implications. It is transmitted by mosquitoes of the genus Aedes, particularly Aedes aegypti, that lives in the domestic and peridomestic habitat. The clinical picture includes fever, headache, retroorbital pain, body pains, rash and malaise. Sometimes patients has a sudden worsening with hypovolemic shock and hemorrhages, high an elevated lethality. Not an antiviral drug is available, but death can be prevented by early intravenous infusion of crystalloid solutions. Some vaccine candidates are being now evaluated. Prevention depends on vector control by health education and environmental reordering.

  15. Isolation of Japanese Encephalitis Virus from Brain Tissues of Bat in Yunnan Province%从云南省蝙蝠脑组织中分离出乙型脑炎病毒

    Institute of Scientific and Technical Information of China (English)

    张海林; 张云智; 黄文丽; 米竹青; 龚鹤琴; 王静林

    2001-01-01

    In July 1997, a strain (GB30) of virus was isolated from 60 samples of brain tissues of Murina aurata (Chiroptera: Vespertilionidae) co llec ted in Gengma county, Yunnan province, China. Isolation of virus was negative fr om 4 samples of brain tissues of Rousettus leschenaulti (Chiroptera: Pteropo did ae) collected in Gengma. GB30 virus strain could regularly cause illness and dea th in suckling mice, produced evident CPE in BHK21 cells. It agglutinated red b lood cells of dove at pH5.75~7.4. This virus has been identified serologically by hemagglutination inhibition and immunofluorescent tests using Japanese enceph alitis (JE), dengue (DEN) type 1,2,3,4, and chikungunya (CHIK) viruses monoclona l antibodies, and JE and sindbis (SIN) viruses immune sera. It showed specific r eaction to JE virus only and no reaction with DEN 1~4, CHIK and SIN viruses. Th erefore it can be identified as JE virus. This is the first report on the isolat ion of JE virus from Murina aurata. The results showed that bats are conside red as the reservoir and amplifier host of JE virus transmission in nature.%为进一步阐明蝙蝠在保存乙脑病毒中的作用,于1997年7月,在云南省耿马 县捕捉蝙蝠64只,取脑组织作病毒分离,从一只金管鼻蝠脑组织中分离出1株病毒。该毒株 能引起BHK21细胞病变和乳鼠发病死亡,在pH5.75~7.4时能凝集鸽红血球,经用单克隆抗 体血凝抑制和免疫荧光试验鉴定,证实为乙型脑炎病毒。进一步证明蝙蝠在乙型脑炎病毒保 存和扩散中具有重要作用。从金管鼻蝠体内分离出乙型脑炎病毒属国内外首次报道。

  16. Immunogenicity of a Live Attenuated Chimeric Japanese Encephalitis Vaccine as a Booster Dose After Primary Vaccination With Live Attenuated SA14-14-2 Vaccine: A Phase IV Study in Thai Children.

    Science.gov (United States)

    Sricharoenchai, Sirintip; Lapphra, Keswadee; Chuenkitmongkol, Sunate; Phongsamart, Wanatpreeya; Bouckenooghe, Alain; Wittawatmongkol, Orasri; Rungmaitree, Supattra; Chokephaibulkit, Kulkanya

    2017-02-01

    This single-group study investigated the immunogenicity and safety of a booster dose of the recently licensed live attenuated chimeric Japanese encephalitis vaccine in 50 healthy children (1-5 years old) who were primed with the live attenuated SA14-14-2 vaccine. A strong anamnestic response was induced 28 days postbooster: geometric mean titer, 9144 (95% confidence interval: 7365-11353); and seroprotection rate, 49 of 49 (100%) children.

  17. Anti Japanese encephalitis virus IgM positivity among patients with acute encephalitic syndrome admitted to different hospitals from all over Nepal

    Science.gov (United States)

    Bhattarai, Anupama; Nepal, Krishus; Adhikari, Sailaja; Sharma, Mukunda; Parajuli, Pramila

    2017-01-01

    The Japanese encephalitis virus (JEV) infection is one of the major public health problems in Nepal because of its increasing disease morbidity and mortality. The main purpose of this study was to determine the anti-JEV IgM positivity among acute encephalitis syndromic cases from all over Nepal. The present study was conducted at National Public Health Laboratory, Kathmandu, Nepal from April 2015 to October 2015. A total of 671 (418 CSF and 253 serum) samples were collected from 625 patients with acute encephalitic syndrome, admitted to different hospitals from all over Nepal. IgM antibody capture enzyme linked immunosorbent assay (ELISA) was used for the detection of anti-JEV IgM positive cases. The rate of anti-JEV IgM positivity was found to be 21.12%. The majority of positive cases (50%) were from the age group below 15 years, with the highest numbers of cases occurring in September (55.30%). Among all the anti-JEV IgM positive cases, higher numbers of cases were males. Geographically, the highest numbers of anti-JEV IgM positive cases were recorded from Terai region. Similarly, largest numbers of anti-JEV IgM positive cases were reported from Kailai district followed by those from Kanchanpur. However, anti-JEV IgM positive cases were also reported from hill districts. Continuation of active surveillance and vector control measures, proper management of diagnostic facilities and expanded program of immunization in JE endemic areas should be strongly emphasized to reduce the endemicity of the disease. PMID:28264024

  18. Adverse events following vaccination with an inactivated, Vero cell culture-derived Japanese encephalitis vaccine in the United States, 2009-2012.

    Science.gov (United States)

    Rabe, Ingrid B; Miller, Elaine R; Fischer, Marc; Hills, Susan L

    2015-01-29

    In March 2009, the U.S. Food and Drug Administration licensed an inactivated, Vero cell culture-derived Japanese encephalitis vaccine (JE-VC [Ixiaro]) for use in adults. The vaccine was licensed based on clinical trial safety data in 3558 JE-VC recipients. It is essential to monitor post-licensure surveillance data to evaluate the safety of JE-VC because rare adverse events may not be detected until the vaccine is administered to a larger population. We reviewed adverse events reported to the U.S. Vaccine Adverse Event Reporting System (VAERS) for adults (≥17 years) who received JE-VC from May 2009 through April 2012. Adverse event reporting rates were calculated using 275,848 JE-VC doses distributed. Over the 3 year period, 42 adverse events following vaccination with JE-VC were reported to VAERS for an overall reporting rate of 15.2 adverse events per 100,000 doses distributed. Of the 42 total reports, 5 (12%) were classified as serious for a reporting rate of 1.8 per 100,000 doses distributed; there were no deaths. Hypersensitivity reactions (N=12) were the most commonly reported type of adverse event, with a rate of 4.4 per 100,000 doses distributed; no cases of anaphylaxis were reported. Three adverse events of the central nervous system were reported (one case of encephalitis and two seizures) for a rate of 1.1 per 100,000; all occurred after receipt of JE-VC with other vaccines. These post-marketing surveillance data suggest a good safety profile for JE-VC consistent with findings from pre-licensure clinical trials. Post-licensure safety data should continue to be monitored for any evidence of rare serious or neurologic adverse events. Published by Elsevier Ltd.

  19. The NS3 and NS4A genes as the targets of RNA interference inhibit replication of Japanese encephalitis virus in vitro and in vivo.

    Science.gov (United States)

    Yuan, Lei; Wu, Rui; Liu, Hanyang; Wen, Xintian; Huang, Xiaobo; Wen, Yiping; Ma, Xiaoping; Yan, Qigui; Huang, Yong; Zhao, Qin; Cao, Sanjie

    2016-12-15

    Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus that can cause acute encephalitis with a high fatality rate. RNA interference (RNAi) is a powerful tool to silence gene expression and a potential therapy for virus infection. In this study, the antiviral ability of eight shRNA expression plasmids targeting different sites of the NS3 and NS4A genes of JEV was determined in BHK21 cells and mice. The pGP-NS3-3 and pGP-NS4A-4 suppressed 93.9% and 82.0% of JEV mRNA in cells, respectively. The virus titer in cells was reduced approximately 950-fold by pretreating with pGP-NS3-4, and 640-fold by pretreating with pGP-NS4A-4. The results of western blot and immunofluorescence analysis showed JEV E protein and viral load in cells were remarkably inhibited by shRNA expression plasmids. The viral load in brains of mice pretreated with pGP-NS3-4 or pGP-NS4A-4 were reduced approximately 2400-fold and 800-fold, respectively, and the survival rate of mice challenged with JEV were 70% and 50%, respectively. However, the antiviral ability of shRNA expression plasmids was decreased over time. This study indicates that RNAi targeting of the NS3 and NS4A genes of JEV can sufficiently inhibit the replication of JEV in vitro and in vivo, and NS3 and NS4A genes might be potential targets of molecular therapy for JEV infection. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Serological evidence of widespread West Nile virus and Japanese encephalitis virus infection in native domestic ducks (Anas platyrhynchos var domesticus) in Kuttanad region, Kerala, India.

    Science.gov (United States)

    Kalaiyarasu, Semmannan; Mishra, Niranjan; Khetan, Rohit Kumar; Singh, Vijendra Pal

    2016-10-01

    Birds can act as reservoirs of West Nile virus (WNV) with a key role in its epidemiology. WNV lineage 1 associated fatal cases of human encephalitis in 2011 and acute flaccid paralysis in 2013 were reported in Alappuzha district, Kerala, India. But no information is available on WNV circulation in domestic ducks, which are abundant, cohabit with humans and occupy wetlands and water bodies in the region. To determine the extent of WNV infection, we investigated 209 sera, 250 oral and 350 cloacal swab samples from local Chara and Chemballi domestic ducks (Anas platyrhynchos var domesticus) in the districts of Alappuzha, Kottayam, Kollam and Pathanamthitta collected during January and March 2015. The serum samples were tested for WNV antibodies first by a competition ELISA and then by a micro virus neutralization test (micro-VNT), while oral and cloacal swabs were subjected to WNV real-time RT-PCR. Ninety five ducks showed evidence of flavivirus antibodies by ELISA. End point neutralizing antibody titre against WNV and Japanese encephalitis virus (JEV) revealed WNV specific antibodies in 24 (11.5%) ducks in 3 districts, JEV specific antibodies in 21 (10%) ducks in 2 districts and flavivirus specific antibodies in 19 (9%) ducks. However, no WNV genomic RNA could be detected. The results of this study demonstrate evidence of widespread WNV and JEV infection in domestic ducks in Kuttanad region, Kerala with a higher seroprevalence to WNV than JEV. Additionally, it highlights the utility of domestic ducks as a surveillance tool to detect WNV/JEV circulation in a region. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Dengue and Severe Dengue

    Science.gov (United States)

    ... 686kB World Health Day 2014: Protect yourself from vector-borne diseases WHO's work on dengue Dengue (Special Programme for Research and Training in Tropical Diseases, TDR) Dengue vaccine development More about dengue Zika virus and potential complications Latest outbreaks Dengue Fever – ...

  2. Rasmussen's Encephalitis

    Science.gov (United States)

    ... speech, paralysis on one side of the body (hemiparesis), inflammation of the brain (encephalitis), and mental deterioration. ... speech, paralysis on one side of the body (hemiparesis), inflammation of the brain (encephalitis), and mental deterioration. ...

  3. An inactivated cell culture Japanese encephalitis vaccine (JE-ADVAX) formulated with delta inulin adjuvant provides robust heterologous protection against West Nile encephalitis via cross-protective memory B cells and neutralizing antibody.

    Science.gov (United States)

    Petrovsky, Nikolai; Larena, Maximilian; Siddharthan, Venkatraman; Prow, Natalie A; Hall, Roy A; Lobigs, Mario; Morrey, John

    2013-09-01

    West Nile virus (WNV), currently the cause of a serious U.S. epidemic, is a mosquito-borne flavivirus and member of the Japanese encephalitis (JE) serocomplex. There is currently no approved human WNV vaccine, and treatment options remain limited, resulting in significant mortality and morbidity from human infection. Given the availability of approved human JE vaccines, this study asked whether the JE-ADVAX vaccine, which contains an inactivated cell culture JE virus antigen formulated with Advax delta inulin adjuvant, could provide heterologous protection against WNV infection in wild-type and β2-microglobulin-deficient (β2m(-/-)) murine models. Mice immunized twice or even once with JE-ADVAX were protected against lethal WNV challenge even when mice had low or absent serum cross-neutralizing WNV titers prior to challenge. Similarly, β2m(-/-) mice immunized with JE-ADVAX were protected against lethal WNV challenge in the absence of CD8(+) T cells and prechallenge WNV antibody titers. Protection against WNV could be adoptively transferred to naive mice by memory B cells from JE-ADVAX-immunized animals. Hence, in addition to increasing serum cross-neutralizing antibody titers, JE-ADVAX induced a memory B-cell population able to provide heterologous protection against WNV challenge. Heterologous protection was reduced when JE vaccine antigen was administered alone without Advax, confirming the importance of the adjuvant to induction of cross-protective immunity. In the absence of an approved human WNV vaccine, JE-ADVAX could provide an alternative approach for control of a major human WNV epidemic.

  4. Comparison of the immunogenicity and safety of measles vaccine administered alone or with live, attenuated Japanese encephalitis SA 14-14-2 vaccine in Philippine infants.

    Science.gov (United States)

    Gatchalian, Salvacion; Yao, Yafu; Zhou, Benli; Zhang, Lei; Yoksan, Sutee; Kelly, Kim; Neuzil, Kathleen M; Yaïch, Mansour; Jacobson, Julie

    2008-04-24

    Japanese encephalitis (JE) virus is a major cause of disease, disability, and death in Asia. An effective, live, attenuated JE vaccine (LJEV) is available; however, its use in routine immunization schedules is hampered by lack of data on concomitant administration with measles vaccine (MV). This study evaluated the immunogenicity and reactogenicity of LJEV and MV when administered at the same or separate study visits in infants younger than 1 year of age. Three groups of healthy infants were randomized to receive LJEV at age of 8 months and MV at 9 months (Group 1; n=100); MV and LJEV together at 9 months (Group 2; n=236); or MV and LJEV at 9 and 10 months, respectively (Group 3; n=235). Blood was obtained 4 weeks after each vaccine administration to determine antibody levels for measles and JE. Reactogenicity was assessed by parental diaries and clinic visits. Four weeks after immunization, measles seroprotection rates (defined as > or =340 mIU/ml) were high and comparable in all three groups and specifically, rates in the combined MV-LJEV (Group 2) were not statistically inferior to those in Group 3 receiving MV separately (96% versus 100%, respectively). Likewise, the LJEV seroprotection rates were high and similar between the three groups. The reactogenicity profiles of the three vaccine schedules were also analogous. LJEV and MV administered together are well tolerated and immunogenic in infants younger than 1 year. These results should facilitate incorporation of LJEV into routine immunization schedules with MV.

  5. Southernmost Asia is the source of Japanese encephalitis virus (genotype 1 diversity from which the viruses disperse and evolve throughout Asia.

    Directory of Open Access Journals (Sweden)

    Xiaoyan Gao

    Full Text Available BACKGROUND: Although a previous study predicted that Japanese encephalitis virus (JEV originated in the Malaysia/Indonesia region, the virus is known to circulate mainly on the Asian continent. However, there are no reported systematic studies that adequately define how JEV then dispersed throughout Asia. METHODOLOGY/PRINCIPAL FINDINGS: In order to understand the mode of JEV dispersal throughout the entire Asian continent and the factors that determine the dispersal characteristics of JEV, a phylogenetic analysis using Bayesian Markov chain Monte Carlo simulations was conducted on all available JEV E gene sequences in GenBank, plus strains recently isolated in China. Here we demonstrate for the first time that JEV lineages can be divided into four endemic cycles, comprising southern Asia, eastern coastal Asia, western Asia, and central Asia. The isolation places of the viruses in each endemic cycle were geographically independent regardless of years, vectors, and hosts of isolation. Following further analysis, we propose that the southernmost region (Thailand, Vietnam, and Yunnan Province, China was the source of JEV transmission to the Asian continent following its emergence. Three independent transmission routes from the south to north appear to define subsequent dispersal of JEV. Analysis of JEV population dynamics further supports these concepts. CONCLUSIONS/SIGNIFICANCE: These results and their interpretation provide new insights into our understanding of JEV evolution and dispersal and highlight its potential for introduction into non-endemic areas.

  6. JE-ADVAX vaccine protection against Japanese encephalitis virus mediated by memory B cells in the absence of CD8(+) T cells and pre-exposure neutralizing antibody.

    Science.gov (United States)

    Larena, Maximilian; Prow, Natalie A; Hall, Roy A; Petrovsky, Nikolai; Lobigs, Mario

    2013-04-01

    JE-ADVAX is a new, delta inulin-adjuvanted, Japanese encephalitis (JE) candidate vaccine with a strong safety profile and potent immunogenicity that confers efficient immune protection not only against JE virus but also against related neurotropic flaviviruses such as West Nile virus. In this study, we investigated the immunological mechanism of protection by JE-ADVAX vaccine using knockout mice deficient in B cells or CD8(+) T cells and poor persistence of neutralizing antibody or by adoptive transfer of immune splenocyte subpopulations. We show that memory B cells induced by JE-ADVAX provide long-lived protection against JE even in the absence of detectable pre-exposure serum neutralizing antibodies and without the requirement of CD8(+) T cells. Upon virus encounter, these vaccine-induced memory B cells were rapidly triggered to produce neutralizing antibodies that then protected immunized mice from morbidity and mortality. The findings suggest that the extent of the B-cell memory compartment might be a better immunological correlate for clinical efficacy of JE vaccines than the currently recommended measure of serum neutralizing antibody. This may explain the paradox where JE protection is observed in some subjects even in the absence of detectable serum neutralizing antibody. Our investigation also established the suitability of a novel flavivirus challenge model (β(2)-microglobulin-knockout mice) for studies of the role of B-cell memory responses in vaccine protection.

  7. Study on the protective efficacy of SA14-14-2 attenuated Japanese encephalitis against different JE virus isolates circulating in China.

    Science.gov (United States)

    Liu, Xinyu; Yu, Yongxin; Li, Maoguang; Liang, Guodong; Wang, Huanyu; Jia, Lili; Dong, Guanmu

    2011-03-03

    Prior to 1976 only Japanese encephalitis virus (JEV) genotype III could be detected in China. Recently, numerous genotype I JEV strains have been isolated from JE patients, mosquitoes and pigs while genotype III strains remain present. Two kinds of JEV vaccines are currently used in China for the prevention disease: the JE live attenuated vaccine (LAV) SA14-14-2 virus and the inactivated P3 strain (IPV) vaccine. The SA14-14-2 and P3 viral strains were isolated in the year of 1953 and 1949 respectively and both belonged to the JEV genotype III. In order to evaluate the protective efficacy of both vaccines against the JEV genotype I isolates we conducted vaccination-challenge protection assays in mice. These data demonstrated that both LAV (≥ 234 pfu virus) and IPV (1:5 dilution) vaccines effectively conferred protection against all 16 isolates tested following intraperitoneal (i.p.) challenge. However, when vaccinated mice were challenged via intracerebral (i.c.) injection, ≥ 60% LAV vaccinated animals were protected against challenge with most JEV isolates but only ≤ 40% protection was observed following vaccination with IPV. These results indicated that JE vaccines used in China still protected effectively against both JEV genotypes now prevalent in China and that the LAV formulation conferred higher levels of protection compared to the protection conferred by IPV.

  8. The effect of precipitation on the transmission of Japanese encephalitis (JE) virus in nature: a complex effect on antibody-positive rate to JE virus in sentinel pigs.

    Science.gov (United States)

    Kurane, Ichiro; Shibasaki, Ken-ichi; Kotaki, Akira; Hijioka, Yasuaki; Takasaki, Tomohiko

    2013-05-03

    Japanese encephalitis (JE) is one of the most important mosquito-borne viral diseases in Asia. Pigs are a natural host and the amplifier of JE virus. The sero-conversion rate to JE virus in sentinel pigs reflects the activity of JE virus in the region. We analyzed whether precipitation has any effect on the sero-conversion rate to JE virus in sentinel pigs. Linear regression analysis was performed to determine the correlations between the levels of precipitation and sero-conversion rates to JE virus, in the entire year and during summertime over the period of 32 years from 1969 to 2000. The levels of the annual and summertime precipitation demonstrated statistically significant positive correlations with sero-conversion rates for the whole of the country and for some regions in Japan. The levels of the summertime precipitation, on the other hand, demonstrated statistically significant inverse correlations with the sero-conversion rates in other regions. Further, the levels of precipitation during preceding 10-day periods from days 1-40 before blood collection showed inverse correlation with antibody-positive rates in some regions. The results indicate that the relationship between the annual and summertime precipitation, and the sero-conversion rate to JE virus is complex; both positive and inverse effects are demonstrated depending on the regions.

  9. Toxicity of saponin isolated from Gymnema sylvestre R. Br. (Asclepiadaceae) against Culex tritaeniorhynchus Giles (Diptera: Culicidae) Japanese encephalitis vector mosquito in India.

    Science.gov (United States)

    Elumalai, Kupppusamy; Dhanasekaran, Shanmugan; Krishnappa, Kaliamoorthy

    2012-12-01

    To determine the larvicidal activity of various extracts of Gymnema sylvestre against the Japanese Encephalitis vector, Culex tritaeniorynchus in Tamilnadu, India. To identify the active principle present in the promising fraction obtained in Chlorofom:Methanol extract of Fraction 2. The G. sylvestre leaf extracts were tested, employing WHO procedure against fourth instar larvae of C. tritaeniorhynchus and the larval mortalities were recorded at various concentrations (6.25, 12.5, 25.0, 50 and 100 µg/mL); the 24h LC50 values of the G. Sylvestre leaf extracts were determined following Probit analysis. It was noteworthy that treatment level 100 µg/mL exhibited highest mortality rates for the three different crude extracts and was significantly different from the mean mortalities recorded for the other concentrations. The LC50 values of 34.756 µg/mL (24.475-51.41), 31.351 µg/mL (20.634-47.043) and 28.577 µg/mL (25.159-32.308) were calculated for acetone, chloroform and methanol extract with the chi-square values of 10.301, 31.351 and 4.093 respectively. The present investigation proved that G. Sylvestre could be possibly utilized as an important component in the Vector Control Program.

  10. Toxicity of saponin isolated from Gymnema sylvestre R. Br. (Asclepiadaceae against Culex tritaeniorhynchus Giles (Diptera: Culicidae Japanese encephalitis vector mosquito in India

    Directory of Open Access Journals (Sweden)

    Kupppusamy Elumalai

    2012-12-01

    Full Text Available To determine the larvicidal activity of various extracts of Gymnema sylvestre against the Japanese Encephalitis vector, Culex tritaeniorynchus in Tamilnadu, India. To identify the active principle present in the promising fraction obtained in Chlorofom:Methanol extract of Fraction 2. The G. sylvestre leaf extracts were tested, employing WHO procedure against fourth instar larvae of C. tritaeniorhynchus and the larval mortalities were recorded at various concentrations (6.25, 12.5, 25.0, 50 and 100 µg/mL; the 24h LC50 values of the G. Sylvestre leaf extracts were determined following Probit analysis. It was noteworthy that treatment level 100 µg/mL exhibited highest mortality rates for the three different crude extracts and was significantly different from the mean mortalities recorded for the other concentrations. The LC50 values of 34.756 µg/mL (24.475-51.41, 31.351 µg/mL (20.634-47.043 and 28.577 µg/mL (25.159-32.308 were calculated for acetone, chloroform and methanol extract with the chi-square values of 10.301, 31.351 and 4.093 respectively. The present investigation proved that G. Sylvestre could be possibly utilized as an important component in the Vector Control Program.

  11. Laboratory transmission of Japanese encephalitis, West Nile, and Getah viruses by mosquitoes (Diptera: Culicidae) collected near Camp Greaves, Gyeonggi Province, Republic of Korea 2003.

    Science.gov (United States)

    Turell, Michael J; Mores, Christopher N; Dohm, David J; Lee, Won-Ja; Kim, Heung-Chul; Klein, Terry A

    2006-09-01

    We conducted experimental studies to evaluate mosquitoes captured in Paju County, Gyeonggi Province, Republic of Korea, for their ability to transmit West Nile virus (family Flaviviridae, genus Flavivirus, WNV), Japanese encephalitis virus (family Flaviviridae, genus Flavivirus, JEV), and Getah virus (family Togaviridae, genus Alphavirus, GETV) under laboratory conditions. Both Culex pipiens pallens Coquillett and Culex tritaeniorhynchus Giles were highly susceptible to infection with WNV, with infection rates > 65% when allowed to feed on chickens with viremias of approximately 10(7) plaque-forming units (PFU) of virus/ml blood. In contrast, Cx. tritaeniorhynchus were significantly more susceptible to JEV or GETV (infection rate 100%) than were the Cx. p. pallens (infection rate 3% for JEV and 0% for GETV) captured in the same area when allowed to feed on chickens with viremias of approximately 10(5) PFU of virus/ml blood. The detection of JEV in field-collected Cx. tritaeniorhynchus in Gyeonggi Province in 2000 and the demonstrated ability of this species to transmit this virus support the importance of the continued vaccination of Koreans against JEV and indicate a risk of infection for nonvaccinated individuals.

  12. Gold nanoparticle-based RT-PCR and real-time quantitative RT-PCR assays for detection of Japanese encephalitis virus

    Science.gov (United States)

    Huang, Su-Hua; Yang, Tsuey-Ching; Tsai, Ming-Hong; Tsai, I.-Shou; Lu, Huang-Chih; Chuang, Pei-Hsin; Wan, Lei; Lin, Ying-Ju; Lai, Chih-Ho; Lin, Cheng-Wen

    2008-10-01

    Virus isolation and antibody detection are routinely used for diagnosis of Japanese encephalitis virus (JEV) infection, but the low level of transient viremia in some JE patients makes JEV isolation from clinical and surveillance samples very difficult. We describe the use of gold nanoparticle-based RT-PCR and real-time quantitative RT-PCR assays for detection of JEV from its RNA genome. We tested the effect of gold nanoparticles on four different PCR systems, including conventional PCR, reverse-transcription PCR (RT-PCR), and SYBR green real-time PCR and RT-PCR assays for diagnosis in the acute phase of JEV infection. Gold nanoparticles increased the amplification yield of the PCR product and shortened the PCR time compared to the conventional reaction. In addition, nanogold-based real-time RT-PCR showed a linear relationship between Ct and template amount using ten-fold dilutions of JEV. The nanogold-based RT-PCR and real-time quantitative RT-PCR assays were able to detect low levels (1-10 000 copies) of the JEV RNA genomes extracted from culture medium or whole blood, providing early diagnostic tools for the detection of low-level viremia in the acute-phase infection. The assays described here were simple, sensitive, and rapid approaches for detection and quantitation of JEV in tissue cultured samples as well as clinical samples.

  13. Spatial and Temporal Variation of Japanese encephalitis Disease and Detection of Disease Hotspots: a Case Study of Gorakhpur District, Uttar Pradesh, India

    Science.gov (United States)

    Verma, S.; Gupta, R. D.

    2014-11-01

    In recent times, Japanese Encephalitis (JE) has emerged as a serious public health problem. In India, JE outbreaks were recently reported in Uttar Pradesh, Gorakhpur. The present study presents an approach to use GIS for analyzing the reported cases of JE in the Gorakhpur district based on spatial analysis to bring out the spatial and temporal dynamics of the JE epidemic. The study investigates spatiotemporal pattern of the occurrence of disease and detection of the JE hotspot. Spatial patterns of the JE disease can provide an understanding of geographical changes. Geospatial distribution of the JE disease outbreak is being investigated since 2005 in this study. The JE incidence data for the years 2005 to 2010 is used. The data is then geo-coded at block level. Spatial analysis is used to evaluate autocorrelation in JE distribution and to test the cases that are clustered or dispersed in space. The Inverse Distance Weighting interpolation technique is used to predict the pattern of JE incidence distribution prevalent across the study area. Moran's I Index (Moran's I) statistics is used to evaluate autocorrelation in spatial distribution. The Getis-Ord Gi*(d) is used to identify the disease areas. The results represent spatial disease patterns from 2005 to 2010, depicting spatially clustered patterns with significant differences between the blocks. It is observed that the blocks on the built up areas reported higher incidences.

  14. Roles of TLR3 and RIG-I in Mediating the Inflammatory Response in Mouse Microglia following Japanese Encephalitis Virus Infection

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    Rong Jiang

    2014-01-01

    Full Text Available Japanese encephalitis virus (JEV infection can cause central nervous system disease with irreversible neurological damage in humans and animals. Evidence suggests that overactivation of microglia leads to greatly increased neuronal damage during JEV infection. However, the mechanism by which JEV induces the activation of microglia remains unclear. Toll-like receptor 3 (TLR3 and retinoic acid-inducible gene I (RIG-I can recognize double-stranded RNA, and their downstream signaling results in production of proinflammatory mediators. In this study, we investigated the roles of TLR3 and RIG-I in the inflammatory response caused by JEV infection in the mouse microglial cell line. JEV infection induced the expression of TLR3 and RIG-I and the activation of extracellular signal-regulated kinase (ERK and p38 mitogen-activated protein kinase (p38MAPK. Knockdown of TLR3 and RIG-I attenuated activation of ERK, p38MAPK, activator protein 1 (AP-1, and nuclear factor κB (NF-κB. Secretion of TNF-α, IL-6, and CCL-2, which was induced by JEV, was reduced by TLR3 and RIG-I knockdown and inhibitors of phosphorylated ERK and p38MAPK. Furthermore, viral proliferation was increased following knockdown of TLR3 and RIG-I. Our findings suggest that the signaling pathways of TLR3 and RIG-I play important roles in the JEV-induced inflammatory response of microglia.

  15. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH interaction with 3' ends of Japanese encephalitis virus RNA and colocalization with the viral NS5 protein

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    Chou Shih-Jie

    2009-04-01

    Full Text Available Abstract Replication of the Japanese encephalitis virus (JEV genome depends on host factors for successfully completing their life cycles; to do this, host factors have been recruited and/or relocated to the site of viral replication. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH, a cellular metabolic protein, was found to colocalize with viral RNA-dependent RNA polymerase (NS5 in JEV-infected cells. Subcellular fractionation further indicated that GAPDH remained relatively constant in the cytosol, while increasing at 12 to 24 hours postinfection (hpi and decreasing at 36 hpi in the nuclear fraction of infected cells. In contrast, the redistribution patterns of GAPDH were not observed in the uninfected cells. Co-immunoprecipitation of GAPDH and JEV NS5 protein revealed no direct protein-protein interaction; instead, GAPDH binds to the 3' termini of plus- and minus-strand RNAs of JEV by electrophoretic mobility shift assays. Accordingly, GAPDH binds to the minus strand more efficiently than to the plus strand of JEV RNAs. This study highlights the findings that infection of JEV changes subcellular localization of GAPDH suggesting that this metabolic enzyme may play a role in JEV replication.

  16. In vitro and in vivo characterization of chimeric duck Tembusu virus based on Japanese encephalitis live vaccine strain SA14-14-2.

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    Wang, Hong-Jiang; Liu, Long; Li, Xiao-Feng; Ye, Qing; Deng, Yong-Qiang; Qin, E-De; Qin, Cheng-Feng

    2016-07-01

    Duck Tembusu virus (DTMUV), a newly identified flavivirus, has rapidly spread to China, Malaysia and Thailand. The potential threats to public health have been well-highlighted; however its virulence and pathogenesis remain largely unknown. Here, by using reverse genetics, a recombinant chimeric DTMUV based on Japanese encephalitis live vaccine strain SA14-14-2 was obtained by substituting the corresponding prM and E genes (named ChinDTMUV). In vitro characterization demonstrated that ChinDTMUV replicated efficiently in mammalian cells with small-plaque phenotype in comparison with its parental viruses. Mouse tests showed ChinDTMUV exhibited avirulent phenotype in terms of neuroinvasiveness, while it retained neurovirulence from its parental virus DTMUV. Furthermore, immunization with ChinDTMUV was evidenced to elicit robust IgG and neutralizing antibody responses in mice. Overall, we successfully developed a viable chimeric DTMUV, and these results provide a useful platform for further investigation of the pathogenesis of DTMUV and development of a live attenuated DTMUV vaccine candidate.

  17. Crystal structure of full-length Zika virus NS5 protein reveals a conformation similar to Japanese encephalitis virus NS5

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    Upadhyay, Anup K.; Longenecker, Kenton; Tripathi, Rakesh; Sun, Chaohong; Kempf, Dale J.

    2017-01-01

    The rapid spread of the recent Zika virus (ZIKV) epidemic across various countries in the American continent poses a major health hazard for the unborn fetuses of pregnant women. To date, there is no effective medical intervention. The nonstructural protein 5 of Zika virus (ZIKV-NS5) is critical for ZIKV replication through the 5′-RNA capping and RNA polymerase activities present in its N-terminal methyltransferase (MTase) and C-terminal RNA-dependent RNA polymerase (RdRp) domains, respectively. The crystal structure of the full-length ZIKV-NS5 protein has been determined at 3.05 Å resolution from a crystal belonging to space group P21212 and containing two protein molecules in the asymmetric unit. The structure is similar to that reported for the NS5 protein from Japanese encephalitis virus and suggests opportunities for structure-based drug design targeting either its MTase or RdRp domain. PMID:28291746

  18. Definition of an epitope on Japanese encephalitis virus (JEV) envelope protein recognized by JEV-specific murine CD8+ cytotoxic T lymphocytes.

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    Takada, K; Masaki, H; Konishi, E; Takahashi, M; Kurane, I

    2000-01-01

    We defined an epitope on the Japanese encephalitis virus (JEV) envelope (E) protein recognized by CD8+ cytotoxic T lymphocytes (CTLs). CTLs induced in JEV-infected BALB/c (H-2d) mice recognized E and/or premembrane (PrM) proteins, while CTLs in C57BL/6J (H-2b) and C3H/HeJ (H-2k) mice did not. JEV-specific CTLs had a phenotype of CD3+ CD4- CD8+. Twenty-four 9-amino acid (a.a.) peptides, which had binding motifs for H-2Kd, H-2Ld or H-2Dd, were synthesized according to the amino acid sequences of PrM and E proteins. CTLs induced by JEV infection recognized only the peptide K-3. Immunization of BALB/c mice with only a group of peptides including K-3 induced CTLs which recognized the homologous K-3 peptide, while immunization with other peptides did not. The peptide K-3 had a binding motif for H-2Kd. This is consistent with the finding that JEV-specific CTLs in BALB/c mice was H-2Kd-restricted. These results indicate that the epitope recognized by CTLs in BALB/c mice is located between a.a. 60 and 68 on the E protein, corresponding to an a.a. sequence of CYHASVTDI.

  19. Gold nanoparticle-based RT-PCR and real-time quantitative RT-PCR assays for detection of Japanese encephalitis virus

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    Huang, S-H; Tsai, M-H; Lin, C-W [Department of Biotechnology, College of Health Science, Asia University, Wufeng, Taichung, Taiwan (China); Yang, T-C; Chuang, P-H [Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung, Taiwan (China); Tsai, I-S; Lu, H-C [Nanotechnology Research Center, Feng Chia University, Taichung, Taiwan (China); Wan Lei; Lin, Y-J [Department of Medical Genetics and Medical Research, China Medical University Hospital, Taichung, Taiwan (China); Lai, C-H [Department of Microbiology and Immunology, China Medical University, Taichung, Taiwan (China)], E-mail: cwlin@mail.cmu.edu.tw

    2008-10-08

    Virus isolation and antibody detection are routinely used for diagnosis of Japanese encephalitis virus (JEV) infection, but the low level of transient viremia in some JE patients makes JEV isolation from clinical and surveillance samples very difficult. We describe the use of gold nanoparticle-based RT-PCR and real-time quantitative RT-PCR assays for detection of JEV from its RNA genome. We tested the effect of gold nanoparticles on four different PCR systems, including conventional PCR, reverse-transcription PCR (RT-PCR), and SYBR green real-time PCR and RT-PCR assays for diagnosis in the acute phase of JEV infection. Gold nanoparticles increased the amplification yield of the PCR product and shortened the PCR time compared to the conventional reaction. In addition, nanogold-based real-time RT-PCR showed a linear relationship between Ct and template amount using ten-fold dilutions of JEV. The nanogold-based RT-PCR and real-time quantitative RT-PCR assays were able to detect low levels (1-10 000 copies) of the JEV RNA genomes extracted from culture medium or whole blood, providing early diagnostic tools for the detection of low-level viremia in the acute-phase infection. The assays described here were simple, sensitive, and rapid approaches for detection and quantitation of JEV in tissue cultured samples as well as clinical samples.

  20. Viral etiology of encephalitis in children in southern Vietnam: results of a one-year prospective descriptive study.

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    Van Tan Le

    Full Text Available BACKGROUND: Acute encephalitis is an important and severe disease in children in Vietnam. However, little is known about the etiology while such knowledge is essential for optimal prevention and treatment. To identify viral causes of encephalitis, in 2004 we conducted a one-year descriptive study at Children's Hospital Number One, a referral hospital for children in southern Vietnam including Ho Chi Minh City. METHODOLOGY/PRINCIPAL FINDINGS: Children less than 16 years of age presenting with acute encephalitis of presumed viral etiology were enrolled. Diagnostic efforts included viral culture, serology and real time (RT-PCRs. A confirmed or probable viral causative agent was established in 41% of 194 enrolled patients. The most commonly diagnosed causative agent was Japanese encephalitis virus (n = 50, 26%, followed by enteroviruses (n = 18, 9.3%, dengue virus (n = 9, 4.6%, herpes simplex virus (n = 1, cytomegalovirus (n = 1 and influenza A virus (n = 1. Fifty-seven (29% children died acutely. Fatal outcome was independently associated with patient age and Glasgow Coma Scale (GCS on admission. CONCLUSIONS/SIGNIFICANCE: Acute encephalitis in children in southern Vietnam is associated with high mortality. Although the etiology remains unknown in a majority of the patients, the result from the present study may be useful for future design of treatment and prevention strategies of the disease. The recognition of GCS and age as predictive factors may be helpful for clinicians in managing the patient.

  1. Guiding dengue vaccine development using knowledge gained from the success of the yellow fever vaccine.

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    Liang, Huabin; Lee, Min; Jin, Xia

    2016-01-01

    Flaviviruses comprise approximately 70 closely related RNA viruses. These include several mosquito-borne pathogens, such as yellow fever virus (YFV), dengue virus (DENV), and Japanese encephalitis virus (JEV), which can cause significant human diseases and thus are of great medical importance. Vaccines against both YFV and JEV have been used successfully in humans for decades; however, the development of a DENV vaccine has encountered considerable obstacles. Here, we review the protective immune responses elicited by the vaccine against YFV to provide some insights into the development of a protective DENV vaccine.

  2. Imaging the interaction between dengue 2 virus and human blood platelets using atomic force and electron microscopy.

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    Ghosh, Kanjaksha; Gangodkar, Shobha; Jain, Preksha; Shetty, Shrimati; Ramjee, Sandhya; Poddar, Pankaj; Basu, Atanu

    2008-06-01

    Thrombocytopenia is frequently associated with dengue virus infection. Host factors such as anti-platelet immunopathogenic processes have been implicated in the origin of dengue-associated thrombocytopenia but the role of dengue virus in directly interacting with platelets and altering their hemostatic property remains incompletely understood. In the present study, we examined the effect of dengue 2 virus on the morphology and physiological activation profile of normal human platelets using atomic force microscopy, electron microscopy and flowcytometry. Platelets obtained from healthy donors were exposed to a cell culture-adapted 10(4) LD(50) dengue 2 virus isolate in vitro and the subsequent effect on morphology and activation biology studied. Our results show that dengue 2 virus exposure at doses comparable to natural viremic states in human infections can activate platelets with an increase in P-selectin expression and fibrinogen-binding property. Atomic force, scanning and transmission electron microscopy also showed typical activation-related morphological changes such as altered platelet membrane architecture, degranulation, presence of filopodia and dilatation of the open canalicular system in the dengue 2 virus-exposed platelets but not in the controls. Importantly, Japanese encephalitis virus exposure at the same dose did not activate platelets or show any morphological changes. Our findings suggest that dengue 2 virus may directly interact with and activate platelets - an event that might be important in the origin of dengue-associated thrombocytopenia. Detailed molecular characterization of this effect might provide key knowledge toward better prophylaxis of the hemostatic complications of dengue disease.

  3. Treatment of viral encephalitis.

    Science.gov (United States)

    Domingues, Renan Barros

    2009-03-01

    Several viruses may cause central nervous system diseases with a broad range of clinical manifestations. The time course of the viral encephalitis can be acute, subacute, or chronic. Pathologically there are encephalitis with direct viral entry into the CNS in which brain parenchyma exhibits neuronal damaging and viral antigens and there are postinfectious autoimmune encephalitis associated with systemic viral infections with brain tissue presenting perivascular aggregation of immune cells and myelin damaging. Some virus affect previously healthy individuals while others produce encephalitis among imunocompromised ones. Factors such evolving lifestyles and ecological changes have had a considerable impact on the epidemiology of some viral encephalitis [e.g. West-Nile virus, and Japanese B virus]. Citomegalovirus and JC virus are examples of infections of the brain that have been seen more frequently because they occur in immunocompromised patients. In the other hand many scientific achievements in neuroimaging, molecular diagnosis, antiviral therapy, immunomodulatory treatments, and neurointensive care have allowed more precise and earlier diagnoses and more efficient treatments, resulting in improved outcomes. In this article, we will present the current drug options in the management of the main acute and chronic viral infection of the central nervous system of immunocompetent and immunocompromised adults, focusing on drugs mechanisms of action, efficacy, and side effects. The early diagnosis and correct management of such diseases can reduce mortality and neurological sequelae; however, even with recent treatment advances, potentially devastating outcomes are still possible.

  4. Human Immune Responses to Dengue Viruses.

    Science.gov (United States)

    1986-07-01

    between the PBL of non- inmune donors and dengue virus-infected cells, which results in IFN production. We use dengue virus-infected B lymphoblastoid cell...or, J.J., M.W. Brandriss, and E.E. Walsh. 1985. Protection against 17D yellow fever encephalitis in mice by passive transfer of monoclonal antibodies

  5. CLINICAL AND DEMOGRAPHIC STUDY OF JAPANESE ENCEPHALITIS PATIENTS ADMITTED IN GAUHATI MEDICAL COLLEGE AND HOSPITAL, GUWAHATI, ASSAM, INDIA DURING 2014 EPIDEMIC

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    Bhaskar

    2015-11-01

    Full Text Available BACKGROUND Japanese Encephalitis is one of the most common causes of Acute Encephalitic Syndrome in Asia. During the period of June to August in 2014 an epidemic occurred in Assam, a northestern state of India. METHODS Patients admitted in the Medicine Department in Gauhati Medical College and Hospital (GMCH, Guwahati, Assam, India, with clinical features of Acute Encephalitic Syndrome (AES i.e. acute onset fever and a change in mental status (including symptoms such as confusion, disorientation, coma, or inability to talk and/or new onset seizures (excluding simple febrile seizures from June to August 2014 underwent ELISA for Japanese Encephalitis Immunoglobulin M in cerebrospinal fluid (CSF at the time of admission. Clinical features, demographic profile and laboratory investigations were recorded in positive patients. RESULTS 226 AES patients were admitted in 6 different units of Medicine ward in GMCH, out of which 76 patients were diagnosed to be JE positive with CSF IgM ESLIA, coming from 17 districts of Assam. Out of 76 patients, 69 patients were from rural area, only 7 patients were from urban area. 59 (77.63% patients were farmers or daily labourers by occupation and 23 (30.26% patients were illiterate. Mean age of patients was 47.7 years and male to female ratio was 1.7:1. Mean duration of fever was 6.5 days, convulsion was found in 13.15% patients, out of which most common was generalised seizure (9.2%. 55.2% patients had meningeal signs, 23.68% patients had focal neurological deficits in the form of hemiparesis and monoparesis and mean GCS score was 9.28. Extra pyramidal features present in patients were rigidity (23.68%, abnormal posturing (15.78% and abnormal movements (23.68%. 23.68% patients had Leukocytosis and Thrombocytopenia was found in 21 (27.6% patients. Mean CSF cell count was 34.34 cells/mm3 with mean 29.67% polymorphs, mean CSF protein and sugar was 56.15 mg/dl and 66.92 mg/dl respectively. Serum bilirubin level was

  6. Nanoformulation of poly(ethylene glycol) polymerized organic insect repellent by PIT emulsification method and its application for Japanese encephalitis vector control.

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    Balaji, A P B; Mishra, Prabhakar; Suresh Kumar, R S; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2015-04-01

    The utilization of increased dosage of insect repellents to overcome mosquito resistance has raised environmental concerns globally. In accord to this, we have formulated an efficacious, water-dispersive, nanometric formulation of a poor water-soluble insect repellent, diethylphenylacetamide (DEPA) by poly(ethylene glycol) (PEG) polymerization followed by PIT emulsification method. The critical micelle concentration of PEG in the spontaneously emulsified conventional DEPA droplets was determined, based on the droplets physical stability. Subjecting them to PIT emulsification yielded monodispersed polymeric nanomicelles of DEPA (Nano DEPA) with hydrodynamic mean diameter of 153.74 nm. The high-resolution scanning and transmission electron microscopic studies revealed the characteristic core-shell structure of micelle. The comparative efficacy of Bulk DEPA and Nano DEPA was evaluated by larvicidal and WHO cone bioassay against the Japanese encephalitis vector Culex tritaeniorhynchus. The median lethal concentrations (48 h) for 3rd instars C. tritaeniorhynchus larvae were found to be 0.416 mg/L for Bulk DEPA and 0.052 mg/L for Nano DEPA, respectively. The median knockdown concentrations (60 min) for the two to three-day-old, sucrose-fed, female adult mosquitoes were 5.372% (v/v) and 3.471% (v/v) for Bulk and Nano DEPA, respectively. Further investigation by histopathological and biochemical studies propound that Nano DEPA exerted better bioefficacy as comparative to its bulk form even at minimal exposure concentrations. Hence, Nano DEPA will serve as an effective alternate in controlling the vector expansion with reduced dosage.

  7. Construction of an infectious molecular clone of Japanese encephalitis virus genotype V and its derivative subgenomic replicon capable of expressing a foreign gene.

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    Ishikawa, Tomohiro; Abe, Makoto; Masuda, Michiaki

    2015-01-02

    Japanese encephalitis virus (JEV) genotype V was originally isolated in Malaysia in 1952 and has long been restricted to the area. In 2009, sudden emergence of the genotype V in China and Korea was reported, suggesting expansion of its geographical distribution. Although studies on the genotype V are becoming more important, they have been limited partly due to lack of its infectious molecular clone. In this study, a plasmid carrying cDNA corresponding to the entire genome of JEV Muar strain, which belongs to genotype V, in the downstream of T7 promoter was constructed. Electroporation of viral RNA transcribed by T7 RNA polymerase (T7RNAP) in vitro from the plasmid led to production of progeny viruses both in mammalian and mosquito cells. Also, transfection of the infectious clone plasmid into mammalian cells expressing T7RNAP transiently or stably was demonstrated to generate infectious progenies. When the viral structural protein genes were partially deleted from the full-length cDNA, the subgenomic RNA transcribed in vitro from the modified plasmid was shown to replicate itself in mammalian cells as a replicon. The replicon carrying the firefly luciferase gene in place of the deleted structural protein genes was also shown to efficiently replicate itself and express luciferase in mammalian cells. Compared with the replicon derived from JEV genotype III (Nakayama strain), the genotype V-derived replicon appeared to be more tolerant to introduction of a foreign gene. The infectious clone and the replicons constructed in this study may serve as useful tools for characterizing JEV genotype V.

  8. Japanese encephalitis virus-based replicon RNAs/particles as an expression system for HIV-1 Pr55 Gag that is capable of producing virus-like particles.

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    Yun, Sang-Im; Song, Byung-Hak; Koo, Yongbum; Jeon, Iksoo; Byun, Sung June; Park, Jong-Hyeon; Joo, Yi-Seok; Kim, Seok-Yong; Lee, Young-Min

    2009-09-01

    Ectopic expression of the structural protein Pr55(Gag) of HIV-1 has been limited by the presence of inhibitory sequences in the gag coding region that must normally be counteracted by HIV-1 Rev and RRE. Here, we describe a cytoplasmic RNA replicon based on the RNA genome of Japanese encephalitis virus (JEV) that is capable of expressing HIV-1 gag without requiring Rev/RRE. This replicon system was constructed by deleting all three JEV structural protein-coding regions (C, prM, and E) from the 5'-proximal region of the genome and simultaneously inserting an HIV-1 gag expression cassette driven by the internal ribosome entry site of encephalomyocarditis virus into the 3'-proximal noncoding region of the genome. Transfection of this JEV replicon RNA led to expression of Pr55(Gag) in the absence of Rev/RRE in the cytoplasm of hamster BHK-21, human HeLa, and mouse NIH/3T3 cells. Production of the Pr55(Gag) derived from this JEV replicon RNA appeared to be increased by approximately 3-fold when compared to that based on an alphavirus replicon RNA. Biochemical and morphological analyses demonstrated that the Pr55(Gag) proteins were released into the culture medium in the form of virus-like particles. We also observed that the JEV replicon RNAs expressing the Pr55(Gag) could be encapsidated into single-round infectious JEV replicon particles when transfected into a stable packaging cell line that provided the three JEV structural proteins in trans. This ectopic expression of the HIV-1 Pr55(Gag) by JEV-based replicon RNAs/particles in diverse cell types may represent a useful molecular platform for various biological applications in medicine and industry.

  9. Memory immune response and safety of a booster dose of Japanese encephalitis chimeric virus vaccine (JE-CV) in JE-CV-primed children.

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    Feroldi, Emmanuel; Capeding, Maria Rosario; Boaz, Mark; Gailhardou, Sophia; Meric, Claude; Bouckenooghe, Alain

    2013-04-01

    Japanese encephalitis chimeric virus vaccine (JE-CV) is a licensed vaccine indicated in a single dose administration for primary immunization. This controlled phase III comparative trial enrolled children aged 36-42 mo in the Philippines. 345 children who had received one dose of JE-CV in a study two years earlier, received a JE-CV booster dose. 105 JE-vaccine-naïve children in general good health were randomized to receive JE-CV (JE-vaccine naïve group; 46 children) or varicella vaccine (safety control group; 59 children). JE neutralizing antibody titers were assessed using PRNT50. Immunological memory was observed in children who had received the primary dose of JE-CV before. Seven days after the JE-CV booster dose administration, 96.2% and 66.8% of children were seroprotected and had seroconverted, respectively, and the geometric mean titer (GMT) was 231 1/dil. Twenty-eight days after the JE-CV booster dose seroprotection and seroconversion were achieved in 100% and 95.3% of children, respectively, and the GMT was 2,242 1/dil. In contrast, only 15.4% of JE-CV-vaccine naïve children who had not received any prior JE vaccine were seroprotected seven days after they received JE-CV. One year after receiving the JE-CV booster dose, 99.4% of children remained seroprotected. We conclude that JE-CV is effective and safe, both as a single dose and when administrated as a booster dose. A booster dose increases the peak GMT above the peak level reached after primary immunization and the antibody persistence is maintained at least one year after the JE-CV booster dose administration. Five year follow up is ongoing.

  10. Envelope Protein Mutations L107F and E138K Are Important for Neurovirulence Attenuation for Japanese Encephalitis Virus SA14-14-2 Strain

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    Jian Yang

    2017-01-01

    Full Text Available The attenuated Japanese encephalitis virus (JEV strain SA14-14-2 has been successfully utilized to prevent JEV infection; however, the attenuation determinants have not been fully elucidated. The envelope (E protein of the attenuated JEV SA14-14-2 strain differs from that of the virulent parental SA14 strain at eight amino acid positions (E107, E138, E176, E177, E264, E279, E315, and E439. Here, we investigated the SA14-14-2-attenuation determinants by mutating E107, E138, E176, E177, and E279 in SA14-14-2 to their status in the parental virulent strain and tested the replication capacity, neurovirulence, neuroinvasiveness, and mortality associated with the mutated viruses in mice, as compared with those of JEV SA14-14-2 and SA14. Our findings indicated that revertant mutations at the E138 or E107 position significantly increased SA14-14-2 virulence, whereas other revertant mutations exhibited significant increases in neurovirulence only when combined with E138, E107, and other mutations. Revertant mutations at all eight positions in the E protein resulted in the highest degree of SA14-14-2 virulence, although this was still lower than that observed in SA14. These results demonstrated the critical role of the viral E protein in controlling JEV virulence and identified the amino acids at the E107 and E138 positions as the key determinants of SA14-14-2 neurovirulence.

  11. Japanese encephalitis virus infection modulates the expression of suppressors of cytokine signaling (SOCS) in macrophages: implications for the hosts' innate immune response.

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    Kundu, Kiran; Dutta, Kallol; Nazmi, Arshed; Basu, Anirban

    2013-01-01

    Viruses have evolved various mechanisms to subvert the host's immune system and one of them is preventing the infected cells from sending out chemotactic signals to activate the adaptive immune response. Japanese encephalitis virus (JEV) is a neuropathologic flavivirus that is responsible for significant number of child mortalities in various parts of South-East Asia. In this study we show that JEV modulates suppressors of cytokine signaling (SOCS)1 and 3 expression in macrophages to bring about changes in the JAK-STAT signaling cascade, so as to inhibit proinflammatory cyto/chemokine release. Using real time PCR, immunoblotting and immunofluorescent staining, we show that the expression of type 1 interferons and intracellular expression of viral genes are also affected over time. Also, following the initial activation of SOCS1 and 3, there is production of interferon-inducible anti-viral proteins in the cells which may be responsible for inhibiting viral replication. However, even at later time points, viral genes were still detected from the macrophages, albeit at lesser quantities, than earlier time points, indicative of intracellular persistence of the virus in a latent form. On knocking down SOCS1 and SOCS3 we found a significant decrease in viral gene expression at an early time point, indicating the dysregulation of the signaling cascade leading to increased production of interferon-inducible anti-viral proteins. Taken together, our study provides an insight into the role of JEV infection in modulating the JAK-STAT pathway with the help of SOCS leading to the generation of an antiviral innate immune response.

  12. miR-146a negatively regulates the induction of proinflammatory cytokines in response to Japanese encephalitis virus infection in microglial cells.

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    Deng, Minnan; Du, Ganqin; Zhao, Jiegang; Du, Xiaowei

    2017-06-01

    Increasing evidence confirms the involvement of virus infection and miRNA, such as miR-146a, in neuroinflammation-associated epilepsy. In the present study, we investigated the upregulation of miR-146a with RT-qPCR and in situ hybridization methods in a mice infection model of Japanese encephalitis virus (JEV) and in vitro. Subsequently we investigated the involvement of miR-146a in modulating JEV-induced neuroinflammation. It was demonstrated that JEV infection promoted miR-146a production in BALB/c mice brain and in cultured mouse microglial C8-B4 cells, along with pro-inflammatory cytokines, such as IL-1β, IL-6, TNF-α, IFN-β and IFN-α. We also found that miR-146a exerted negative regulatory effects upon IL-1β, IL-6, TNF-α, IFN-β and IFN-α in C8-B4 cells. Accordingly, miR-146a downregulation with a miR-146a inhibitor promoted the upregulation of IL-1β, IL-6, TNF-α, IFN-β and IFN-α, whereas miR-146a upregulation with miR-146a mimics reduced the upregulation of these cytokines. Moreover, miR-146a exerted no regulation upon JEV growth in C8-B4 cells. In conclusion, JEV infection upregulated miR-146a and pro-inflammatory cytokine production, in mice brain and in cultured C8-B4 cells. Furthermore, miR-146a negatively regulated the production of JEV-induced pro-inflammatory cytokines, in virus growth independent fashion, identifying miR-146a as a negative feedback regulator in JEV-induced neuroinflammation, and possibly in epilepsy.

  13. Long-term Immunogenicity of a Single Dose of Japanese Encephalitis Chimeric Virus Vaccine in Toddlers and Booster Response 5 Years After Primary Immunization.

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    Kosalaraksa, Pope; Watanaveeradej, Veerachai; Pancharoen, Chitsanu; Capeding, Maria Rosario; Feroldi, Emmanuel; Bouckenooghe, Alain

    2017-04-01

    Japanese encephalitis (JE) is an important mosquito-borne viral disease that is endemic in Asia, Western Pacific countries and Northern Australia. Although there is no antiviral treatment, vaccination is effective in preventing this disease. We followed a cohort of 596 children for 5 years after primary vaccination at 12-18 months of age with JE chimeric virus vaccine (JE-CV; IMOJEV) in a multicenter, phase III trial in Thailand and the Philippines to assess antibody persistence and safety. At the end of the 5 years, a subgroup of 85 participants, at 1 site in Thailand, was followed after administration of a JE-CV booster vaccination. JE antibody titers were measured annually after primary vaccination and 28 days after booster vaccination using a 50% plaque reduction neutralization test. Seroprotection was defined as a JE-CV neutralizing antibody titer ≥10 (1/dil). Kaplan-Meier survival analysis was used to estimate the proportion of participants maintaining protective JE-CV neutralizing antibody titers. At 1, 2, 3, 4 and 5 years after vaccination with JE-CV, 88.5%, 82.9%, 78.2%, 74.0% and 68.6% of the participants followed remained seroprotected. Geometric mean titers in the subgroup assessed after receipt of a booster dose increased from 61.2 (95% confidence interval: 43.8-85.7) pre-booster to 4951 (95% confidence interval: 3928-6241) 28 days post-booster, with all participants seroprotected. There were no safety concerns identified. Protective immune responses persisted for at least 5 years after a JE-CV primary immunization in the majority of participants. JE-CV booster induced a robust immune response even after a 5-year interval.

  14. Isolation of Japanese encephalitis and Getah viruses from mosquitoes (Diptera: Culicidae) collected near Camp Greaves, Gyonggi Province, Republic of Korea, 2000.

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    Turell, Michael J; O'Guinn, Monica L; Wasieloski, Leonard P; Dohm, David J; Lee, Wan-Ja; Cho, Hae-Wol; Kim, Heung-Chol; Burkett, Douglas A; Mores, Christopher N; Coleman, Russell E; Klein, Terry A

    2003-07-01

    As part of an evaluation of the ecology of arthropod-borne diseases in the Republic of Korea (ROK), we examined 8,765 mosquitoes captured in Paju County, Gyonggi Province, ROK, for the presence of viruses. Mosquitoes were captured in propane lantern/human-baited Shannon traps, Mosquito Magnet traps, or American Biophysics Corporation (East Greenwich, RI) miniature light traps with or without supplemental octenol bait and/or dry ice. Mosquitoes were identified to species, placed in pools of up to 40 mosquitoes each, and tested on Vero cells for the presence of virus. A total of 15 virus isolations were made from 293 pools of mosquitoes. Viruses were identified by reverse transcriptase-polymerase chain reaction and sequencing and consisted of 14 isolations of Japanese encephalitis (JE) virus and one isolation of Getah (GET) virus. All JE isolates were from Culex tritaeniorhynchus Giles, and the isolate of GET was from Aedes vexans (Meigen). The minimum field infection rate for JE in Cx. tritaeniorhynchus was 3.3 per 1,000, whereas the GET virus infection rate for Ae. vexans was 0.2 per 1,000. Isolation of JE and GET indicated that both viruses were actively circulating in northern Gyonggi Province, ROK. The lack of human cases of JE among the Korean population probably is because of an effective government-mandated vaccination program. The reason for no cases among >10,000 United States military and others that reside or train nearby is unknown, but may be related to personnel protection measures (permethrin-impregnated uniforms and use of deet repellent), adult mosquito control, mosquito selection of nonhuman hosts (unpublished data), and the low symptomatic to asymptomatic ratio of disease in adults.

  15. Cytoplasmic translocation of polypyrimidine tract-binding protein and its binding to viral RNA during Japanese encephalitis virus infection inhibits virus replication.

    Directory of Open Access Journals (Sweden)

    Deepika Bhullar

    Full Text Available Japanese encephalitis virus (JEV has a single-stranded, positive-sense RNA genome containing a single open reading frame flanked by the 5'- and 3'-non-coding regions (NCRs. The virus genome replicates via a negative-sense RNA intermediate. The NCRs and their complementary sequences in the negative-sense RNA are the sites for assembly of the RNA replicase complex thereby regulating the RNA synthesis and virus replication. In this study, we show that the 55-kDa polypyrimidine tract-binding protein (PTB interacts in vitro with both the 5'-NCR of the positive-sense genomic RNA--5NCR(+, and its complementary sequence in the negative-sense replication intermediate RNA--3NCR(-. The interaction of viral RNA with PTB was validated in infected cells by JEV RNA co-immunoprecipitation and JEV RNA-PTB colocalization experiments. Interestingly, we observed phosphorylation-coupled translocation of nuclear PTB to cytoplasmic foci that co-localized with JEV RNA early during JEV infection. Our studies employing the PTB silencing and over-expression in cultured cells established an inhibitory role of PTB in JEV replication. Using RNA-protein binding assay we show that PTB competitively inhibits association of JEV 3NCR(- RNA with viral RNA-dependent RNA polymerase (NS5 protein, an event required for the synthesis of the plus-sense genomic RNA. cAMP is known to promote the Protein kinase A (PKA-mediated PTB phosphorylation. We show that cells treated with a cAMP analogue had an enhanced level of phosphorylated PTB in the cytoplasm and a significantly suppressed JEV replication. Data presented here show a novel, cAMP-induced, PTB-mediated, innate host response that could effectively suppress JEV replication in mammalian cells.

  16. Protection of mice against Japanese encephalitis virus group II strain infections by combinations of monoclonal antibodies to different antigenic domains on glycoprotein E

    Directory of Open Access Journals (Sweden)

    Ashok Kumar Gupta

    2012-01-01

    Full Text Available A combination of at least three hemagglutination- inhibition-positive (HAI and virus-specific (Hs monoclonal antibodies (MAbs to glycoprotein E (gpE of Japanese encephalitis virus (JEV fully protected (100% mice against JEV strain 733913 infections (group 1. However, these representative epitopes are reported to have been lost on JEV group II strains. In the present study, therefore, the protective effect of various combinations of anti-gpE MAbs representing antigenic epitopes other than Hs was studied on mice infections with JEV group II strains: JEV strains 641686 and 691004. MAbs used in the protective experiments were characterized as HAI-negative virus-specific (NHs and HAI-positive flavivirus cross-reactive (Hx. Additionally, one of the Hs MAbs (MAb Hs-3 was included in the experiments. Mice were first administered single MAbs or their combinations intraperitoneally and 24 h later, infected with the virus intracerebrally. Protection rates of 70-75% were obtained with a combination of four MAbs: MAbs NHs-1, Hx-1, Hx-3 and Hs-3. However, protection rates of only 20-40% were obtained with three MAbs but none was observed with single or two MAbs. There was, however, a substantial increase in mice survival. The protective effect of several combinations of anti-gpE MAbs representing different antigenic epitopes might be due to the enhancement of binding within the same group and also between different MAb groups. The present results indicate that NHs and Hx epitopes should be incorporated with three Hs epitopes in a JEV vaccine that would have an added advantage, particularly in the flaviviral endemic areas with JEV strain variations.

  17. The effects of climatic factors on the distribution and abundance of Japanese encephalitis vectors in Kurnool district of Andhra Pradesh, India

    Directory of Open Access Journals (Sweden)

    U. Suryanarayana Murty, M. Srinivasa Rao , N. Arunachalam

    2010-03-01

    Full Text Available Background & objectives: Climatic attributes have been associated with relative mosquito abundanceand transmission of mosquito borne infections in many parts of the world, especially in warm andtropical climatic regions. The main objectives of this study were to assess the change in seasonalpattern of Japanese encephalitis (JE vectors, their density, to elucidate whether the lagged climatevariables (precipitation, temperature and humidity are associated with JE vector density, and todetermine if temperature and precipitation are similarly important for the rise in the number ofpotential mosquito vectors for JE virus in the temperate climate of Andhra Pradesh, India.Methods: Mosquito samples were collected from Kurnool district of Andhra Pradesh using handcatch and light-trap methods during 2002 to 2006. The type and abundance of recovered specieswere compared to ecological correlates. In each geographic area, temperature and precipitationare the two possible proxy variables for mosquito density, in conjunction with other seasonalfactors for JE epidemics.Results: Out of the various mosquito species collected, Culex gelidus and Cx. tritaeniorhynchuswere noticed in high numbers. There was considerably high prevalence of Cx. gelidus (68.05% inurban area than in rural areas whereas, Cx. tritaeniorhynchus (57.51% was found to be more inrural areas than in the urban area. It is noticed that the factors such as rainfall and temperaturewere found to be correlated with the per man hour (PMH density, whereas the humidity wasinversely correlated with the PMH.Interpretation & conclusion: The environmental and eco-climatic factors are assisting in enhancingthe breeding of these mosquitoes in Kurnool district of Andhra Pradesh, India. Both Cx.tritaeniorhyncus and Cx. gelidus are quite adaptable to these environmental conditions and thisnecessitates immediate control measures in both rural and urban areas of Kurnool district.

  18. Paradoxical role of antibodies in dengue virus infections: considerations for prophylactic vaccine development.

    Science.gov (United States)

    Acosta, Eliana G; Bartenschlager, Ralf

    2016-01-01

    Highly effective prophylactic vaccines for flaviviruses including yellow fever virus, tick-borne encephalitis virus and Japanese encephalitis virus are currently in use. However, the development of a dengue virus (DENV) vaccine has been hampered by the requirement of simultaneous protection against four distinct serotypes and the threat that DENV-specific antibodies might either mediate neutralization or, on the contrary, exacerbate disease through the phenomenon of antibody-dependent enhancement (ADE) of infection. Therefore, understanding the cellular, biochemical and molecular basis of antibody-mediated neutralization and ADE are fundamental for the development of a safe DENV vaccine. Here we summarize current structural and mechanistic knowledge underlying these phenomena. We also review recent results demonstrating that the humoral immune response triggered during natural DENV infection is able to generate neutralizing antibodies binding complex quaternary epitopes only present on the surface of intact virions.

  19. Histidine at Residue 99 and the Transmembrane Region of the Precursor Membrane prM Protein Are Important for the prM-E Heterodimeric Complex Formation of Japanese Encephalitis Virus

    OpenAIRE

    Lin, Ying-Ju; Wu, Suh-Chin

    2005-01-01

    The formation of the flavivirus prM-E complex is an important step for the biogenesis of immature virions, which is followed by a subsequent cleavage of prM to M protein through cellular protease to result in the production and release of mature virions. In this study, the intracellular formation of the prM-E complex of Japanese encephalitis virus was investigated by baculovirus coexpression of prM and E in trans in Sf9 insect cells as analyzed by anti-E antibody immunoprecipitation and sucro...

  20. Co-expression of Japanese encephalitis virus prM-E-NS1 antigen with granulocyte-macrophage colony-stimulating factor enhances humoral and anti-virus immunity after DNA vaccination.

    Science.gov (United States)

    Gao, Na; Chen, Wei; Zheng, Qun; Fan, Dong-ying; Zhang, Jun-lei; Chen, Hui; Gao, George F; Zhou, De-shan; An, Jing

    2010-03-10

    Japanese encephalitis virus (JEV) is an agent of Japanese encephalitis, and granulocyte-macrophage colony-stimulating factor (GM-CSF) is an attractive DNA vaccine adjuvant for its antigen presentation. In the present study, we have constructed DNA vaccines that carried JEV prM-E-NS1 genes with or without the GM-CSF gene. Immunization with the bicistronic plasmid pCAG-JEGM that co-expresses GM-CSF and viral prM-E-NS1, resulted in the highest IgG response and sufficient protection against virus-challenged BALB/c mice. However, much to our surprise, co-inoculation of the GM-CSF plasmid with the pCAG-JE plasmid expressing viral prM-E-NS1 lead to a low antibody titer and a relatively low survival rate. Moreover, anamnestic antibody-mediated protection played a dominant role in the mice JEV challenge model, according to the enhancement of post-challenge neutralizing antibody titers and further adoptive transfer experiments. Taken together, this study should encourage further development of JEV DNA vaccine strategies and caution against the use of cytokines as an adjuvant.

  1. Findings at brain MRI in children with dengue fever and neurological symptoms.

    Science.gov (United States)

    Rastogi, Ruchi; Garg, Bhavya

    2016-01-01

    Dengue is a flavivirus of the genus arbovirus with four serotypes, from DEN 1 to DEN 4. There has been an increase in incidence of dengue infection in children in the tropics and subtropics. Dengue has a variable clinical presentation, with many patients being asymptomatic. Its clinical manifestations in children vary from fever and arthralgia to life-threatening dengue hemorrhagic fever and dengue shock syndrome. We describe MRI findings in children with neurological involvement including dengue encephalopathy, acute hypoxic injury and dengue encephalitis. Dengue encephalopathy is usually secondary to multisystem derangement such as shock, hepatitis, coagulopathy and concurrent bacterial infection and is relatively common. Dengue encephalitis from direct neuronal invasion is rare. Nonspecific changes are seen on brain MRI in dengue infection. Clinical and laboratory findings as well as outcome do not necessarily correspond with brain MRI findings.

  2. Findings at brain MRI in children with dengue fever and neurological symptoms

    Energy Technology Data Exchange (ETDEWEB)

    Rastogi, Ruchi; Garg, Bhavya [Indraprastha Apollo Hospitals, Department of Radiodiagnosis, New Delhi (India)

    2016-01-15

    Dengue is a flavivirus of the genus arbovirus with four serotypes, from DEN 1 to DEN 4. There has been an increase in incidence of dengue infection in children in the tropics and subtropics. Dengue has a variable clinical presentation, with many patients being asymptomatic. Its clinical manifestations in children vary from fever and arthralgia to life-threatening dengue hemorrhagic fever and dengue shock syndrome. We describe MRI findings in children with neurological involvement including dengue encephalopathy, acute hypoxic injury and dengue encephalitis. Dengue encephalopathy is usually secondary to multisystem derangement such as shock, hepatitis, coagulopathy and concurrent bacterial infection and is relatively common. Dengue encephalitis from direct neuronal invasion is rare. Nonspecific changes are seen on brain MRI in dengue infection. Clinical and laboratory findings as well as outcome do not necessarily correspond with brain MRI findings. (orig.)

  3. A Single Dose of Vero Cell–Derived Japanese Encephalitis (JE) Vaccine (Ixiaro) Effectively Boosts Immunity in Travelers Primed With Mouse Brain–Derived JE Vaccines

    Science.gov (United States)

    Erra, Elina O.; Askling, Helena Hervius; Rombo, Lars; Riutta, Jukka; Vene, Sirkka; Yoksan, Sutee; Lindquist, Lars; Pakkanen, Sari H.; Huhtamo, Eili; Vapalahti, Olli; Kantele, Anu

    2012-01-01

    Background. A significant part of the world population lives in areas with endemic Japanese encephalitis (JE). For travelers from nonendemic countries, Vero cell–derived vaccine (JE-VC; Ixiaro) has replaced traditional mouse brain–derived vaccines (JE-MB) associated with safety concerns. The 2 vaccines are derived from different viral strains: JE-VC from the SA14-14-2 strain and JE-MB from the Nakayama strain. No data exist regarding whether JE-VC can be used to boost immunity after a primary series of JE-MB; therefore, a primary series of JE-VC has been recommended to all travelers regardless of previous vaccination history. Methods. One hundred twenty travelers were divided into 4 groups: Volunteers with no prior JE vaccination received primary immunization with (group 1) JE-MB or (group 2) JE-VC, and those primed with JE-MB received a single booster dose of (group 3) JE-MB or (group 4) JE-VC. Immune responses were tested before and 4–8 weeks after vaccination using plaque reduction neutralization test (PRNT) against both vaccine strains. Results. In vaccine-naive travelers, the vaccination response rate for test strains Nakayama and SA14-14-2 was 100% and 87% after primary vaccination with JE-MB and 87% and 94% after JE-VC, respectively. Antibody levels depended on the target virus, with higher titers against homologous than heterologous PRNT50 target strain (P < .001). In travelers primed with JE-MB, vaccination response rates were 91% and 91%, and 98% and 95% after a booster dose of JE-MB or JE-VC, respectively. Subgroup analysis revealed that a higher proportion of primed (98%/95%) than nonprimed (39%/42%) volunteers responded to a single dose of JE-VC (P < .001). Conclusions. A single dose of JE-VC effectively boosted immunity in JE-MB–primed travelers. Current recommendations should be reevaluated. Clinical Trials Registration. NCT01386827. PMID:22696017

  4. Antibody responses to an immunodominant nonstructural 1 synthetic peptide in patients with dengue fever and dengue hemorrhagic fever.

    Science.gov (United States)

    Huang, J H; Wey, J J; Sun, Y C; Chin, C; Chien, L J; Wu, Y C

    1999-01-01

    Two flaviviruses, dengue (DEN) virus and Japanese encephalitis (JE) virus, are important because of their global distribution and the frequency of epidemics in tropical and subtropical areas. To study the B-cell epitopes of nonstructural 1 (NS1) glycoprotein and anti-NS1 antibody response in DEN infection, a series of 15-mer synthetic peptides from the predicted B-cell linear epitopes of DEN-2 NS1 protein were prepared. Enzyme-linked immunosorbent assay (ELISA) was performed to analyze antibody responses to these peptides from sera of both DEN and JE patients. One peptide derived from DEN-2 NS1, D2 NS1-P1 (amino acids 1-15), was identified as the immunodominant epitope that reacted with sera from dengue fever (DF) patients but not JE patients. The isotype of D2 NS1-P1-specific antibodies was mainly immunoglobulin M (IgM) in all sera that tested positive. A specificity study demonstrated that sera from all four DEN types reacted with D2 NS1-P1. A dynamics study showed that specific antibodies to this peptide could be detected as early as 2 days after the onset of symptoms. We observed significant anti-D2 NS1-P1 antibody responses in 45% of patients with primary and secondary infections with DF or with dengue hemorrhagic fever. This is the first report demonstrating that significant anti-DEN NS1 antibodies can be induced in the sera of patients with primary DEN infection.

  5. Establishment and running status on Japanese Encephalitis laboratory network in Guizhou%贵州省乙脑实验室网络的建立及运转

    Institute of Scientific and Technical Information of China (English)

    叶绪芳; 赵苏晔; 刘淳婷; 梁国栋; 付士红; 高晓艳; 王环宇; 翟友刚; 蒋凤

    2013-01-01

    目的 分析评价贵州省乙脑实验室网络建立和运转情况,为提高乙脑实验室检测质量及监测信息管理水平提供参考数据.方法 对贵州省2006~2010年乙脑实验室网络的各项实验室监测指标进行分析,对网络建立后的各项运转指标进行评价.结果 (1)贵州省乙脑实验室网络于2006年8月建立,含1个省级和9个市(州、地区,下同)级乙脑血清学实验室,形成了贵州省乙脑疑似病例的实验室快速反应诊断系统. (2) 2006~2010年采集到报告疑似乙脑及病毒性脑炎病例血清和/或脑脊液标本共3814例(疑似乙脑3627例,病脑187例)4749份,疑似乙脑病例标本采集率为85.1% (75.2%~98.6%). (3)对所有采集到标本的3814例报告病例进行乙脑IgM抗体检测,阳性2533例(疑似乙脑2496例,病脑37例),疑似乙脑病例乙脑IgM阳性率在48.0%~85.9%之间,实验室确诊率在70.3%~83.2%之间;对2006~2007年381例乙脑阴性病例进行腮腺炎等10种其他常见病脑病毒IgM抗体检测,阳性206例,阳性率54.1%;从2006年报告病例的113份脑脊液中分离到2株基因Ⅰ型乙脑病毒. (4) 2009年、2010年接受国家对省级乙脑实验室每年一次的职能考核,成绩均为满分;2009年、2010年省级每年组织对市级乙脑实验室进行职能考核,每年9个市级考核成绩均达100分;2007~2010年省级对市级乙脑实验室的抽样复核省地符合率在92.3%~100%之间.结论 (1)贵州省已建立了省、市级CDC乙脑血清学和病原学监测实验室网络,并且运转良好. (2)通过乙脑实验室网络的良好运转,提高了乙脑报告病例的标本采集率和实验室确诊率,为贵州省控制乙脑工作奠定了实验室基础. (3)但仍需加强网络实验室管理和质量控制,克服松懈麻痹思想.%OBJECTIVE To evaluate the establishment and running status of Japanese Encephalitis (JE) laboratory network in Guizhou, China

  6. Acanthamoeba encephalitis

    Directory of Open Access Journals (Sweden)

    Kaushal V

    2008-01-01

    Full Text Available Central nervous system infection with free-living amoebae is rare. We present a fatal case of Acanthamoeba encephalitis in a 63-year-old female from India where acanthamoebae were demonstrated and cultured from CSF. In spite of treatment with amphotericin B, fluconazole and rifampicin the patient did not survive. Amoebic infection should be suspected in a patient of encephalitis of unexplained aetiology as timely diagnosis can lead to a favourable outcome.

  7. Detection of the mosquito-borne flaviviruses, West Nile, Dengue, Saint Louis Encephalitis, Ilheus, Bussuquara, and Yellow Fever in free-ranging black howlers (Alouatta caraya) of Northeastern Argentina

    Science.gov (United States)

    Morales, María A.; Fabbri, Cintia M.; Zunino, Gabriel E.; Kowalewski, Martín M.; Luppo, Victoria C.; Enría, Delia A.; Levis, Silvana C.; Calderón, Gladys E.

    2017-01-01

    Several medically important mosquito-borne flaviviruses have been detected in Argentina in recent years: Dengue (DENV), St. Louis encephalitis (SLEV), West Nile (WNV) and Yellow Fever (YFV) viruses. Evidence of Bussuquara virus (BSQV) and Ilheus virus (ILHV) activity were found, but they have not been associated with human disease. Non-human primates can act as important hosts in the natural cycle of flaviviruses and serological studies can lead to improved understanding of virus circulation dynamics and host susceptibility. From July–August 2010, we conducted serological and molecular surveys in free–ranging black howlers (Alouatta caraya) captured in northeastern Argentina. We used 90% plaque-reduction neutralization tests (PRNT90) to analyze 108 serum samples for antibodies to WNV, SLEV, YFV, DENV (serotypes 1and 3), ILHV, and BSQV. Virus genome detection was performed using generic reverse transcription (RT)-nested PCR to identify flaviviruses in 51 antibody-negative animals. Seventy animals had antibodies for one or more flaviviruses for a total antibody prevalence of 64.8% (70/108). Monotypic (13/70, 19%) and heterotypic (27/70, 39%) patterns were differentiated. Specific neutralizing antibodies against WNV, SLEV, DENV-1, DENV-3, ILHV, and BSQV were found. Unexpectedly, the highest flavivirus antibody prevalence detected was to WNV with 9 (8.33%) monotypic responses. All samples tested by (RT)-nested PCR were negative for viral genome. This is the first detection of WNV-specific antibodies in black howlers from Argentina and the first report in free-ranging non-human primates from Latin-American countries. Given that no animals had specific neutralizing antibodies to YFV, our results suggest that the study population remains susceptible to YFV. Monitoring of these agents should be strengthened to detect the establishment of sylvatic cycles of flaviviruses in America and evaluate risks to wildlife and human health. PMID:28187130

  8. Detection of the mosquito-borne flaviviruses, West Nile, Dengue, Saint Louis Encephalitis, Ilheus, Bussuquara, and Yellow Fever in free-ranging black howlers (Alouatta caraya) of Northeastern Argentina.

    Science.gov (United States)

    Morales, María A; Fabbri, Cintia M; Zunino, Gabriel E; Kowalewski, Martín M; Luppo, Victoria C; Enría, Delia A; Levis, Silvana C; Calderón, Gladys E

    2017-02-01

    Several medically important mosquito-borne flaviviruses have been detected in Argentina in recent years: Dengue (DENV), St. Louis encephalitis (SLEV), West Nile (WNV) and Yellow Fever (YFV) viruses. Evidence of Bussuquara virus (BSQV) and Ilheus virus (ILHV) activity were found, but they have not been associated with human disease. Non-human primates can act as important hosts in the natural cycle of flaviviruses and serological studies can lead to improved understanding of virus circulation dynamics and host susceptibility. From July-August 2010, we conducted serological and molecular surveys in free-ranging black howlers (Alouatta caraya) captured in northeastern Argentina. We used 90% plaque-reduction neutralization tests (PRNT90) to analyze 108 serum samples for antibodies to WNV, SLEV, YFV, DENV (serotypes 1and 3), ILHV, and BSQV. Virus genome detection was performed using generic reverse transcription (RT)-nested PCR to identify flaviviruses in 51 antibody-negative animals. Seventy animals had antibodies for one or more flaviviruses for a total antibody prevalence of 64.8% (70/108). Monotypic (13/70, 19%) and heterotypic (27/70, 39%) patterns were differentiated. Specific neutralizing antibodies against WNV, SLEV, DENV-1, DENV-3, ILHV, and BSQV were found. Unexpectedly, the highest flavivirus antibody prevalence detected was to WNV with 9 (8.33%) monotypic responses. All samples tested by (RT)-nested PCR were negative for viral genome. This is the first detection of WNV-specific antibodies in black howlers from Argentina and the first report in free-ranging non-human primates from Latin-American countries. Given that no animals had specific neutralizing antibodies to YFV, our results suggest that the study population remains susceptible to YFV. Monitoring of these agents should be strengthened to detect the establishment of sylvatic cycles of flaviviruses in America and evaluate risks to wildlife and human health.

  9. Dengue fever

    Science.gov (United States)

    ... the mosquito Aedes aegypti , which is found in tropic and subtropic regions. This area includes parts of: ... encephalitis, St. Louis encephalitis, tick-borne encephalitis, Kyasanur forest disease, Alkhurma hemorrhagic fever, Zika). In: Bennett JE, ...

  10. Replication of Japanese Encephalitis Virus.

    Science.gov (United States)

    1980-12-10

    division , school, laboratory, etc., of the author. List city, state, and ZIP Code. Block 10 Program Element, Project, Task Area, and Work Unit Numbers...largely of smooth and some rough intracytoplasmic membranes. ....4’ .... ..... . 14 Table 4. Phospholipid distribution in celular membranes and virions

  11. A molecularly cloned, live-attenuated japanese encephalitis vaccine SA14-14-2 virus: a conserved single amino acid in the ij Hairpin of the Viral E glycoprotein determines neurovirulence in mice.

    Science.gov (United States)

    Yun, Sang-Im; Song, Byung-Hak; Kim, Jin-Kyoung; Yun, Gil-Nam; Lee, Eun-Young; Li, Long; Kuhn, Richard J; Rossmann, Michael G; Morrey, John D; Lee, Young-Min

    2014-07-01

    Japanese encephalitis virus (JEV), a mosquito-borne flavivirus that causes fatal neurological disease in humans, is one of the most important emerging pathogens of public health significance. JEV represents the JE serogroup, which also includes West Nile, Murray Valley encephalitis, and St. Louis encephalitis viruses. Within this serogroup, JEV is a vaccine-preventable pathogen, but the molecular basis of its neurovirulence remains unknown. Here, we constructed an infectious cDNA of the most widely used live-attenuated JE vaccine, SA14-14-2, and rescued from the cDNA a molecularly cloned virus, SA14-14-2MCV, which displayed in vitro growth properties and in vivo attenuation phenotypes identical to those of its parent, SA14-14-2. To elucidate the molecular mechanism of neurovirulence, we selected three independent, highly neurovirulent variants (LD50, 1.5×105 PFU) by serial intracerebral passage in mice. Complete genome sequence comparison revealed a total of eight point mutations, with a common single G1708→A substitution replacing a Gly with Glu at position 244 of the viral E glycoprotein. Using our infectious SA14-14-2 cDNA technology, we showed that this single Gly-to-Glu change at E-244 is sufficient to confer lethal neurovirulence in mice, including rapid development of viral spread and tissue inflammation in the central nervous system. Comprehensive site-directed mutagenesis of E-244, coupled with homology-based structure modeling, demonstrated a novel essential regulatory role in JEV neurovirulence for E-244, within the ij hairpin of the E dimerization domain. In both mouse and human neuronal cells, we further showed that the E-244 mutation altered JEV infectivity in vitro, in direct correlation with the level of neurovirulence in vivo, but had no significant impact on viral RNA replication. Our results provide a crucial step toward developing novel therapeutic and preventive strategies against JEV and possibly other encephalitic flaviviruses.

  12. Expansion of syndromic vaccine preventable disease surveillance to include bacterial meningitis and Japanese encephalitis: evaluation of adapting polio and measles laboratory networks in Bangladesh, China and India, 2007-2008.

    Science.gov (United States)

    Cavallaro, Kathleen F; Sandhu, Hardeep S; Hyde, Terri B; Johnson, Barbara W; Fischer, Marc; Mayer, Leonard W; Clark, Thomas A; Pallansch, Mark A; Yin, Zundong; Zuo, Shuyan; Hadler, Stephen C; Diorditsa, Serguey; Hasan, A S M Mainul; Bose, Anindya S; Dietz, Vance

    2015-02-25

    Surveillance for acute flaccid paralysis with laboratory confirmation has been a key strategy in the global polio eradication initiative, and the laboratory platform established for polio testing has been expanded in many countries to include surveillance for cases of febrile rash illness to identify measles and rubella cases. Vaccine-preventable disease surveillance is essential to detect outbreaks, define disease burden, guide vaccination strategies and assess immunization impact. Vaccines now exist to prevent Japanese encephalitis (JE) and some etiologies of bacterial meningitis. We evaluated the feasibility of expanding polio-measles surveillance and laboratory networks to detect bacterial meningitis and JE, using surveillance for acute meningitis-encephalitis syndrome in Bangladesh and China and acute encephalitis syndrome in India. We developed nine syndromic surveillance performance indicators based on international surveillance guidelines and calculated scores using supervisory visit reports, annual reports, and case-based surveillance data. Scores, variable by country and targeted disease, were highest for the presence of national guidelines, sustainability, training, availability of JE laboratory resources, and effectiveness of using polio-measles networks for JE surveillance. Scores for effectiveness of building on polio-measles networks for bacterial meningitis surveillance and specimen referral were the lowest, because of differences in specimens and techniques. Polio-measles surveillance and laboratory networks provided useful infrastructure for establishing syndromic surveillance and building capacity for JE diagnosis, but were less applicable for bacterial meningitis. Laboratory-supported surveillance for vaccine-preventable bacterial diseases will require substantial technical and financial support to enhance local diagnostic capacity. Published by Elsevier Ltd.

  13. Potensi Kurkumin dan Pentagamavunon-0 sebagai Anti Viral Dengue - 2

    Directory of Open Access Journals (Sweden)

    Dewi Marbawati

    2015-07-01

    Full Text Available AbstractMore than 40% of the world's population who live in tropical and subtropical regions at risk for dengue infection. Specific and effective antiviral therapies to treat dengue infection has not been found yet. Many researches proved that curcumin has preventive activity againts viruses, such as vasicular stomatis (VSV, HSV 1 and 2, parainfluenza-3, reovirus-1, feline corona virus, feline herpes virus. Curcumin also known to perform the inhibition of ubiquitin - proteasome system that decreasethe production of Japanese encephalitis in neuroblastoma cells. Pentagamavunon-0 (PGV-0 is expected to have better activity than curcumin. This study aims to determine the cytotoxic effect andthe potential of curcumin and PGV-0 as antiviral Dengue-2 on vero cells. Including experimental study. Cytotoxic test performed to obtain a safe concentration of curcumin and PGV-0 on vero cells followed by antiviral test using immunocytochemistry SBPC (Streptavidin Biotin Peroxidase Complex. The results showed that the safe concentrations for curcumin is 6.25 ppm and PGV-0 is 1.5625 ppm based on cytotoxic test to vero cell. The positive rate from Immunocytochemistry test showed that no significant difference between curcumin and PGV-0 treatment. However, when compared with the positive control results are significantly different. We concluded both curcumin and PGV-0 can reduce the positive rate caused Dengue-2 infection at one day incubation.Keywords : Dengue-2, curcumin, pentagamavunon-0 (PGV-0, ImmunocytochemistryAbstrakLebih dari 40 % populasi dunia yang tinggal di daerah tropis dan subtropis mempunyai risiko untuk terjangkit infeksi Dengue. Terapi yang spesifik dan efektif untuk mengobati infeksi Dengue belum ditemukan. Kurkumin terbukti memiliki aktivitas preventif terhadap beberapa virus, antara lain:vasicular stomatis (VSV, HSV 1 dan 2, parainfluenza-3, reovirus-1, feline corona virus, feline herpes virus. Kurkumin juga diketahui mampu melakukan

  14. Potensi Kurkumin dan Pentagamavunon-0 sebagai Anti Viral Dengue - 2

    Directory of Open Access Journals (Sweden)

    Dewi Marbawati

    2015-07-01

    Full Text Available AbstractMore than 40% of the world's population who live in tropical and subtropical regions at risk for dengue infection. Specific and effective antiviral therapies to treat dengue infection has not been found yet. Many researches proved that curcumin has preventive activity againts viruses, such as vasicular stomatis (VSV, HSV 1 and 2, parainfluenza-3, reovirus-1, feline corona virus, feline herpes virus. Curcumin also known to perform the inhibition of ubiquitin - proteasome system that decreasethe production of Japanese encephalitis in neuroblastoma cells. Pentagamavunon-0 (PGV-0 is expected to have better activity than curcumin. This study aims to determine the cytotoxic effect andthe potential of curcumin and PGV-0 as antiviral Dengue-2 on vero cells. Including experimental study. Cytotoxic test performed to obtain a safe concentration of curcumin and PGV-0 on vero cells followed by antiviral test using immunocytochemistry SBPC (Streptavidin Biotin Peroxidase Complex. The results showed that the safe concentrations for curcumin is 6.25 ppm and PGV-0 is 1.5625 ppm based on cytotoxic test to vero cell. The positive rate from Immunocytochemistry test showed that no significant difference between curcumin and PGV-0 treatment. However, when compared with the positive control results are significantly different. We concluded both curcumin and PGV-0 can reduce the positive rate caused Dengue-2 infection at one day incubation.Keywords : Dengue-2, curcumin, pentagamavunon-0 (PGV-0, ImmunocytochemistryAbstrakLebih dari 40 % populasi dunia yang tinggal di daerah tropis dan subtropis mempunyai risiko untuk terjangkit infeksi Dengue. Terapi yang spesifik dan efektif untuk mengobati infeksi Dengue belum ditemukan. Kurkumin terbukti memiliki aktivitas preventif terhadap beberapa virus, antara lain:vasicular stomatis (VSV, HSV 1 dan 2, parainfluenza-3, reovirus-1, feline corona virus, feline herpes virus. Kurkumin juga diketahui mampu melakukan

  15. 首次接种乙型脑炎减毒活疫苗引起小儿高热1例%High fever in children following live attenuated Japanese encephalitis first-time vaccination: a case report

    Institute of Scientific and Technical Information of China (English)

    王筱婧; 左艳敏; 吴婷婷; 田硕

    2011-01-01

    One case of child fever cause by live attenuated Japanese encephalitis vaccine was reported and analyzed in this study. The temperature of the child patient was attempted to 39.3℃. After treating with paracetamol and physical cooling, the patient's temperature was fallen to normal.%本文对1例首次接种乙型脑炎减毒活疫苗后引起小儿高热的不良反应进行了报道.患儿体温达到39.3℃,口服给予泰诺林及进行物理降温治疗后,患儿体温恢复正常,情况好转.

  16. Single dose of SA 14-14-2 vaccine provides long-term protection against Japanese encephalitis: a case-control study in Nepalese children 5 years after immunization. drjbtandan@yahoo.com.

    Science.gov (United States)

    Tandan, J B; Ohrr, Heechoul; Sohn, Young Mo; Yoksan, Sutee; Ji, Min; Nam, Chung Mo; Halstead, Scott B

    2007-06-28

    In July 1999, a single dose of live-attenuated SA 14-14-2 Japanese encephalitis (JE) vaccine was administered to children living in the Bardiya, Banke and Kailali districts of Nepal. In 2004, the original vaccinated population experienced a fifth seasonal exposure to JE. We performed a case-control study comparing the prevalence of the administration of vaccine in patients with JE hospitalized in the Bardiya and Bheri Zonal hospitals and in age-sex matched controls resident in the Bardiya district. Among the 219 village controls, 114 had been vaccinated (52.1%) while only one of 20 JE cases had received live-attenuated JE vaccine. Five years after administration of a single dose, SA 14-14-2 provided a protective efficacy of 96.2% (CI 73.1-99.9%).

  17. Safety and immunogenicity of a freeze-dried, Vero cell culture-derived, inactivated Japanese encephalitis vaccine (KD-287, ENCEVAC®) versus a mouse brain-derived inactivated Japanese encephalitis vaccine in children: a phase III, multicenter, double-blinded, randomized trial.

    Science.gov (United States)

    Yun, Ki Wook; Lee, Hoan Jong; Kang, Jin Han; Eun, Byung Wook; Kim, Yae-Jean; Kim, Kyung-Hyo; Kim, Nam Hee; Hong, Young Jin; Kim, Dong Ho; Kim, Hwang Min; Cha, Sung-Ho

    2015-01-08

    Although mouse brain-derived, inactivated Japanese encephalitis vaccines (JE-MBs) have been successfully used for a long time, potential rare neurological complications have prompted the development of a Vero cell culture-derived inactivated vaccine (JE-VC). In a phase III clinical study, we aimed to compare the safety and immunogenicity of a JE-VC, KD-287 with a JE-MB, JEV-GCC, in children. In this multicenter, double-blinded, randomized controlled trial, the study population consisted of 205 healthy Korean children aged 12-23 months. Each subject was subcutaneously vaccinated with either KD-287 or JEV-GCC twice at an interval of 2 weeks and then vaccinated once 12 months after the second vaccination. Neutralizing antibodies were measured by the plaque reduction neutralization test using the homologous and heterologous, as a post hoc analysis, challenge virus strains. The three-dose regimen of KD-287 showed a comparable safety profile with JEV-GCC except higher incidence of fever after the first dose (30.4% and 14.7%, respectively). Most of the fever was mild degree (61.3% and 66.7%, respectively). KD-287 fulfilled the non-inferiority criteria for seroconversion rate (SCR) and geometric mean titer (GMT) of the neutralizing antibody, which were the primary endpoints, at 4 weeks after the third vaccination (95% CI: -1.00, 3.10 for the SCR difference and 10.8, 17.6 for the GMT ratio). The SCRs of KD-287 were all 100% and the GMTs were higher in the KD-287 group than in the JEV-GCC group after the second vaccination and before and after the third vaccination (GMT ratio: 5.59, 20.13, and 13.79, respectively, p < 0.001 in all). GMTs were higher in the KD-287 group in the heterologous analysis also (GMT ratio: 4.05, 5.15, and 4.19, respectively, p < 0.001 in all). This study suggests that the KD-287, a JE-VC is as safe as and may be more effective than the licensed MB-derived vaccine. KD-287 could thus be useful as a second-generation vaccine and substitute

  18. Anti-NMDA Receptor Encephalitis and Vaccination

    Science.gov (United States)

    Wang, Hsiuying

    2017-01-01

    Anti-N-methyl-d-aspartate (Anti-NMDA) receptor encephalitis is an acute autoimmune neurological disorder. The cause of this disease is often unknown, and previous studies revealed that it might be caused by a virus, vaccine or tumor. It occurs more often in females than in males. Several cases were reported to be related to vaccination such as the H1N1 vaccine and tetanus/diphtheria/pertussis and polio vaccines. In this study, we reported an anti-NMDA receptor encephalitis case that may be caused by Japanese encephalitis vaccination. To investigate the association between anti-NMDA receptor encephalitis and vaccination, we analyzed the phylogenetic relationship of the microRNAs, which significantly regulate these vaccine viruses or bacteria, and the phylogenetic relationship of these viruses and bacteria. This reveals that anti-NMDA receptor encephalitis may be caused by Japanese encephalitis vaccination, as well as H1N1 vaccination or tetanus/diphtheria/pertussis and polio vaccinations, from the phylogenetic viewpoint. PMID:28106787

  19. Anti-NMDA Receptor Encephalitis and Vaccination

    Directory of Open Access Journals (Sweden)

    Hsiuying Wang

    2017-01-01

    Full Text Available Anti-N-methyl-d-aspartate (Anti-NMDA receptor encephalitis is an acute autoimmune neurological disorder. The cause of this disease is often unknown, and previous studies revealed that it might be caused by a virus, vaccine or tumor. It occurs more often in females than in males. Several cases were reported to be related to vaccination such as the H1N1 vaccine and tetanus/diphtheria/pertussis and polio vaccines. In this study, we reported an anti-NMDA receptor encephalitis case that may be caused by Japanese encephalitis vaccination. To investigate the association between anti-NMDA receptor encephalitis and vaccination, we analyzed the phylogenetic relationship of the microRNAs, which significantly regulate these vaccine viruses or bacteria, and the phylogenetic relationship of these viruses and bacteria. This reveals that anti-NMDA receptor encephalitis may be caused by Japanese encephalitis vaccination, as well as H1N1 vaccination or tetanus/diphtheria/pertussis and polio vaccinations, from the phylogenetic viewpoint.

  20. Anti-NMDA Receptor Encephalitis and Vaccination.

    Science.gov (United States)

    Wang, Hsiuying

    2017-01-18

    Anti-N-methyl-d-aspartate (Anti-NMDA) receptor encephalitis is an acute autoimmune neurological disorder. The cause of this disease is often unknown, and previous studies revealed that it might be caused by a virus, vaccine or tumor. It occurs more often in females than in males. Several cases were reported to be related to vaccination such as the H1N1 vaccine and tetanus/diphtheria/pertussis and polio vaccines. In this study, we reported an anti-NMDA receptor encephalitis case that may be caused by Japanese encephalitis vaccination. To investigate the association between anti-NMDA receptor encephalitis and vaccination, we analyzed the phylogenetic relationship of the microRNAs, which significantly regulate these vaccine viruses or bacteria, and the phylogenetic relationship of these viruses and bacteria. This reveals that anti-NMDA receptor encephalitis may be caused by Japanese encephalitis vaccination, as well as H1N1 vaccination or tetanus/diphtheria/pertussis and polio vaccinations, from the phylogenetic viewpoint.

  1. CCL2, but not its receptor, is essential to restrict immune privileged central nervous system-invasion of Japanese encephalitis virus via regulating accumulation of CD11b(+) Ly-6C(hi) monocytes.

    Science.gov (United States)

    Kim, Jin Hyoung; Patil, Ajit Mahadev; Choi, Jin Young; Kim, Seong Bum; Uyangaa, Erdenebileg; Hossain, Ferdaus Mohd Altaf; Park, Sang-Youel; Lee, John Hwa; Kim, Koanhoi; Eo, Seong Kug

    2016-10-01

    Japanese encephalitis virus (JEV) is a re-emerging zoonotic flavivirus that poses an increasing threat to global health and welfare due to rapid changes in climate and demography. Although the CCR2-CCL2 axis plays an important role in trafficking CD11b(+) Ly-6C(hi) monocytes to regulate immunopathological diseases, little is known about their role in monocyte trafficking during viral encephalitis caused by JEV infection. Here, we explored the role of CCR2 and its ligand CCL2 in JE caused by JEV infection using CCR2- and CCL2-ablated murine models. Somewhat surprisingly, the ablation of CCR2 and CCL2 resulted in starkly contrasting susceptibility to JE. CCR2 ablation induced enhanced resistance to JE, whereas CCL2 ablation highly increased susceptibility to JE. This contrasting regulation of JE progression by CCR2 and CCL2 was coupled to central nervous system (CNS) infiltration of Ly-6C(hi) monocytes and Ly-6G(hi) granulocytes. There was also enhanced expression of CC and CXC chemokines in the CNS of CCL2-ablated mice, which appeared to induce CNS infiltration of these cell populations. However, our data revealed that contrasting regulation of JE in CCR2- and CCL2-ablated mice was unlikely to be mediated by innate natural killer and adaptive T-cell responses. Furthermore, CCL2 produced by haematopoietic stem cell-derived leucocytes played a dominant role in CNS accumulation of Ly-6C(hi) monocytes in infected bone marrow chimeric models, thereby exacerbating JE progression. Collectively, our data indicate that CCL2 plays an essential role in conferring protection against JE caused by JEV infection. In addition, blockage of CCR2, but not CCL2, will aid in the development of strategies for prophylactics and therapeutics of JE.

  2. Comparison of the live-attenuated Japanese encephalitis vaccine SA14-14-2 strain with its pre-attenuated virulent parent SA14 strain: similarities and differences in vitro and in vivo.

    Science.gov (United States)

    Yun, Sang-Im; Song, Byung-Hak; Polejaeva, Irina A; Davies, Christopher J; White, Kenneth L; Lee, Young-Min

    2016-10-01

    Japanese encephalitis virus (JEV) is the main cause of acute viral encephalitis, primarily affecting children and young adults in the Asia-Pacific region. JEV is a vaccine-preventable pathogen, with four types of JE vaccine licensed in different regions of the world. To date, the most common JEV strain used in vaccine development and production is SA14-14-2, an attenuated strain derived from its wild-type parental strain SA14. In this study, we directly compared the phenotypic and genotypic characteristics of SA14 and SA14-14-2 to determine the biological and genetic properties associated with their differential virulence. In susceptible BHK-21 cells, SA14-14-2 grew slightly more slowly and formed smaller plaques than SA14, but unlike SA14, it showed almost no expression of the viral protein NS1', the product of a conserved predicted RNA pseudoknot-mediated ribosomal frameshift. In weanling ICR mice, SA14-14-2 was highly attenuated in terms of both neuroinvasiveness and neurovirulence, with its median lethal doses invariably over five logs higher than those of SA14 when inoculated intramuscularly and intracerebrally. Interestingly, the neurovirulence of SA14-14-2 was dependent on mouse age, with the 1- to 7-day-old mice being highly susceptible and the 14- to 21-day-old mice becoming resistant to intracerebral inoculation. At the genome level, SA14-14-2 differed from SA14 by 57 nucleotides, including one silent G-to-A substitution at position 3599 within the predicted RNA pseudoknot for NS1' synthesis; of the 57 differences, 25 resulted in amino acid substitutions. Our data pave the way for the development of new genetically modified JE vaccines.

  3. Production and characterization of monoclonal antibody specific to recombinant dengue multi-epitope protein.

    Science.gov (United States)

    Abhyankar, Ajay Vinayak; Bhargava, Rakesh; Jana, Asha Mukul; Sahni, Ajay Kumar; Rao, P V Lakshmana

    2008-06-01

    Monoclonal antibodies against novel dengue recombinant protein were produced following immunization of Balb/c mice with recombinant dengue multi-epitope protein (r-DMEP) expressed in Escherichia coli vector and purified in a single-step chromatography system. Antigenicity of r-DMEP was evaluated by dot enzyme immunoassay. Mice were immunized intraperitoneally with five doses each of 100 microg of this novel antigen at 1-week intervals and a final intravenous booster dose prior to the fusion. Hybridomas resulted from fusion of myeloma cells and splenocytes using PEG-1500 as an additive. Selection of the hybrids was done using HAT medium, and the hybrids thus selected were finally screened qualitatively and quantitatively by dot and plate immunoassays, respectively. Five antibody secretory hybrid clones exhibited specific reactivity against r-DMEP by dot-ELISA, whereas a lone clone was found to be cross-reactive with Japanese encephalitis virus (JEV). Monoclonal antibodies (MAbs) specific to r-DME protein recognized the envelope and non-structural epitopes by Western blot analysis. These MAbs were further checked for their diagnostic efficacy using dengue suspected clinical samples and found overall sensitivity and specificity for DRDE dipstick ELISA. MAb-based dipstick ELISA results were 85%, 75% and 85%, 90%, respectively.

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

    Directory of Open Access Journals (Sweden)

    Cecília Luiza Simões dos Santos

    2006-02-01

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

  5. Viral aetiology and clinico-epidemiological features of acute encephalitis syndrome in eastern India.

    Science.gov (United States)

    Rathore, S K; Dwibedi, B; Kar, S K; Dixit, S; Sabat, J; Panda, M

    2014-12-01

    This study reports clinico-epidemiological features and viral agents causing acute encephalitis syndrome (AES) in the eastern Indian region through hospital-based case enrolment during April 2011 to July 2012. Blood and CSF samples of 526 AES cases were investigated by serology and/or PCR. Viral aetiology was identified in 91 (17·2%) cases. Herpes simplex virus (HSV; types I or II) was most common (16·1%), followed by measles (2·6%), Japanese encephalitis virus (1·5%), dengue virus (0·57%), varicella zoster virus (0·38%) and enteroviruses (0·19%). Rash, paresis and cranial nerve palsies were significantly higher (P Case-fatality rates were 10·9% and 6·2% in AES cases with and without viral aetiology, respectively. Simultaneous infection of HSV I and measles was observed in seven cases. This report provides the first evidence on viral aetiology of AES viruses from eastern India showing dominance of HSV that will be useful in informing the public health system.

  6. Multiplex real-time RT-PCR for detecting chikungunya virus and dengue virus

    Institute of Scientific and Technical Information of China (English)

    Piyathida Pongsiri; Kesmanee Praianantathavorn; Apiradee Theamboonlers; Sunchai Payungporn; Yong Poovorawan

    2012-01-01

    ABSTRACT Objective:To develop diagnostic test for detection chikungunya virus (CHIKV and Dengue virus (DENV)infection.Methods:We have performed a rapid, accurate laboratory confirmative method to simultaneously detect, quantify and differentiateCHIKV and DENV infection by single-step multiplex real-timeRT-PCR.Results: The assay’s sensitivity was97.65%, specificity was 92.59% and accuracy was95.82% when compared to conventional RT-PCR. Additionally, there was no cross-reaction betweenCHIKV, DENV, Japanese encephalitis virus, hepatitis C, hepatitis A or hepatitis E virus.Conclusions:This rapid and reliable assay provides a means for simultaneous early diagnosis ofCHIKV andDENV in a single-step reaction.

  7. Immune-enhancing effect of nano-DNA vaccine encoding a gene of the prME protein of Japanese encephalitis virus and BALB/c mouse granulocyte-macrophage colony-stimulating factor.

    Science.gov (United States)

    Zhai, Yongzhen; Zhou, Yan; Li, Ximei; Feng, Guohe

    2015-07-01

    Plasmid-encoded granulocyte-macrophage colony-stimulating factor (GM‑CSF) is an adjuvant for genetic vaccines; however, how GM-CSF enhances immunogenicity remains to be elucidated. In the present study, it was demonstrated that injection of a plasmid encoding the premembrane (prM) and envelope (E) protein of Japanese encephalitis virus and mouse GM-CSF (pJME/GM-CSF) into mouse muscle recruited large and multifocal conglomerates of macrophages and granulocytes, predominantly neutrophils. During the peak of the infiltration, an appreciable number of immature dendritic cells (DCs) appeared, although no T and B-cells was detected. pJME/GM-CSF increased the number of splenic DCs and the expression of major histocompatibility complex class II (MHCII) on splenic DC, and enhanced the antigenic capture, processing and presentation functions of splenic DCs, and the cell-mediated immunity induced by the vaccine. These findings suggested that the immune-enhancing effect by pJME/GM-CSF was associated with infiltrate size and the appearance of integrin αx (CD11c)+cells. Chitosan-pJME/GM-CSF nanoparticles, prepared by coacervation via intramuscular injection, outperformed standard pJME/GM-CSF administrations in DC recruitment, antigen processing and presentation, and vaccine enhancement. This revealed that muscular injection of chitosan‑pJME/GM-CSF nanoparticles may enhance the immunoadjuvant properties of GM-CSF.

  8. Complete genome characterization of Rocio virus (Flavivirus: Flaviviridae), a Brazilian flavivirus isolated from a fatal case of encephalitis during an epidemic in Sao Paulo state.

    Science.gov (United States)

    Medeiros, Daniele B A; Nunes, Márcio R T; Vasconcelos, Pedro F C; Chang, Gwong-Jen J; Kuno, Goro

    2007-08-01

    The flaviviruses of major medical importance in South American countries are yellow fever, dengue, Saint Louis encephalitis, West Nile and Rocio viruses. Rocio virus (ROCV) has been responsible for epidemics of severe encephalitis in Brazil with a case-fatality rate of 10 % and development of sequelae in 20 % of the survivors. We have sequenced and characterized the entire genome of ROCV for the first time, by determining the general traits of the open reading frame and the characteristics of viral genes including the potential cleavage sites, conserved or unique motifs, cysteine residues and potential glycosylation sites. The conserved sequences in the 3'-non-coding region were identified, and the predicted secondary structures during cyclization between 5'- and 3'-non-coding regions were studied. Multiple protein and phylogenetic analyses based on antigenically important and phylogenetically informative genes confirmed a close relationship between ROCV and Ilheus virus (ILHV), together constituting a unique and distinct phylogenetic subgroup as well as the genetic relationship of ROCV with several members of the Japanese encephalitis group. Although ROCV is phylogenetically related to ILHV, our study shows that it is still a virus distinct from the latter virus. This is the first flavivirus uniquely indigenous to Brazil that has been sequenced completely and the genome characterized. The data should be useful for further studies at the molecular level, including construction of infectious clone, identification of gene function, improved disease surveillance based on molecular diagnostic tools and vaccine development.

  9. Dengue fever with unusual thalamic involvement.

    Science.gov (United States)

    Mallick, Asim Kumar; Purkait, Radheshyam; Sinhamahapatra, Tapan Kumar

    2012-01-01

    Dengue is the most important mosquito-borne viral disease in the world and is caused by four distinct viruses (type 1 to 4) that are closely related antigenically. Infection by dengue virus may be asymptomatic or may lead to undifferentiated fever, dengue fever or dengue haemorrhagic fever. Recent observations indicate that the clinical profile of dengue is changing and the neurological complications are being reported more frequently. The neurological features includeheadache, seizures, neck stiffness, depressed sensorium, behavioural disorders, delirium, paralysis and cranial nerve palsies. Such neurological symptoms in dengue fever wereattributed to cerebral oedema, haemorrhage, haemoconcentration due to increasing vascular permeability, coagulopathy and release of toxic substances. Cerebral oedema, encephalitis-like changes (oedema and scattered focal lesions), intracranial haemorrhages as well as selective involvement of bilateral hippocampus in dengue infection have been reported previously on selective neuro-imaging but thalamic involvement is rare. We here report a case of a typical presentation of encephalopathy with left sided complete hemiplegia due to thalamic involvement in dengue infection.

  10. Meningitis and Encephalitis

    Science.gov (United States)

    ... for viral encephalitis or other severe viral infections.Anticonvulsants are used to prevent or treat seizures. Corticosteroidd ... for viral encephalitis or other severe viral infections.Anticonvulsants are used to prevent or treat seizures. Corticosteroidd ...

  11. Eastern Equine Encephalitis

    Science.gov (United States)

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

  12. Sero diagnosis of dengue activity in an unknown febrile outbreak at the Siliguri Town, District Darjeeling, West Bengal

    Institute of Scientific and Technical Information of China (English)

    Debjani Taraphdar; Arindam Sarkar; Mihir Kumar Bhattacharya; Shyamalendu Chatterjee

    2010-01-01

    Objective:To investigate the outbreak of unknown fever at Siliguri town, Darjeeling District on request from the State Health Department, Government of West Bengal. Methods:Investigations were made to the affected wards, Sub Divisional Hospital and the nursing homes of Siliguri Town. Duration of illness was 3-5 days. Interesting observations were made in some cases which had gastrointestinal disorders with high serum glutamate pyruvate transaminase (SGPT) and serum glutamic oxaloacetic transaminase (SGOT) levels. A total of 69 blood samples and 7 throat swabs (in Minimum Essential Media) were collected and brought to the ICMR Virus Unit, Kolkata for analysis. Mosquitoes from different affected areas were collected for the identification of the definite vector. Results:Amongst the 69 blood samples, 42 (60.86%) were positive to IgM antibody against dengue virus by Mac enzyme-linked immunosorbent assay (ELISA) test. No IgM antibody to Japanese encephalitis virus was detected among the collected blood samples. Based on the clinical symptoms, presence of IgM antibody to dengue virus and identification of Aedes mosquito, it amply proves that, the illness of those cases were due to dengue virus infection. Conclusions:Based on clinical-epidemiological observations of the investigations the possibility of a communicable disease of viral origin, the detection of IgM antibody and the identification of Aedes egypti, and the potential circulation of denge virus in Siliguri town for the first time were all suggested.

  13. IDENTIFICATION OF THE REGION OF NS1′ PROTEIN RESULTED FROM RIBOSOMAL FRAMESHIFT IN JAPANESE ENCEPHALITIS VIRUS%乙型脑炎病毒NS1′蛋白移码序列的鉴定

    Institute of Scientific and Technical Information of China (English)

    郑浩; 童光志

    2012-01-01

    The sequence resulted from -1 ribosomal frameshifl in the NS1 coding region was amplified using three primers and cloned in triplex into a prokaryotic expression vector pET-28a. The recombinant plasmid pET3NS was transformed into E.coli BL-21 competent cells. The target proteins was expressed with IPTG induction and purified with His-Bind Purification Kit. Mice were immunized with the purified proteins and polyclonal antibodies were prepared. The polyclonal antibodies were reacted in IFA with Japanese encephalitis virus (JEV) proteins in Vero cells infected with JEV. Total proteins of Vero ceils infected with JEV were prepared. Western blot results showed that the monoclonal antibodies against NS 1 of JEV reacted with both NS 1 and NS 1′, while the polyclonal antibodies reacted only with NS 1′. These results indicated that the sequence of the expressed protein was partially identical to that of NSI' and NS 1′ was the product resulted from -1 ribosomal frameshift in the NS1 coding region.%本文通过对猪乙型脑炎病毒(Japanese encephalitis virus,JEV)基因组中移码序列分析,设计合成三条引物,通过PCR扩增出假定的NS1′移码片段,并将移码片段三倍重复克隆入pET-28a表达载体中。重组质粒转化E.coliBL-21后,经IPTG诱导在37℃下实现目的片段的可溶性表达。纯化表达产物,并免疫小鼠制备了多抗血清,以多抗血清为一抗,对JEv感染的Vero细胞进行免疫荧光分析,结果发现抗移码片段表达蛋白的血清可识别JEV蛋白。以JEV感染Vero细胞,提取感染细胞总蛋白,分别以NSl单抗和VAI-制备的多抗血清为一抗,进行Westernblot分析。结果显示,NS1单抗为一抗,可染出48kDa的NS1条带和56kDa的NS1′条带:而以多抗血清为一抗,仅染出56kDa的条带。上述结果显示,多抗血清识别的NS1′蛋白为NS1′移码后片段表达的蛋白。

  14. A randomized study of the immunogenicity and safety of Japanese encephalitis chimeric virus vaccine (JE-CV) in comparison with SA14-14-2 vaccine in children in the Republic of Korea.

    Science.gov (United States)

    Kim, Dong Soo; Houillon, Guy; Jang, Gwang Cheon; Cha, Sung-Ho; Choi, Soo-Han; Lee, Jin; Kim, Hwang Min; Kim, Ji Hong; Kang, Jin Han; Kim, Jong-Hyun; Kim, Ki Hwan; Kim, Hee Soo; Bang, Joon; Naimi, Zulaikha; Bosch-Castells, Valérie; Boaz, Mark; Bouckenooghe, Alain

    2014-01-01

    A new live attenuated Japanese encephalitis chimeric virus vaccine (JE-CV) has been developed based on innovative technology to give protection against JE with an improved immunogenicity and safety profile. In this phase 3, observer-blind study, 274 children aged 12-24 months were randomized 1:1 to receive one dose of JE-CV (Group JE-CV) or the SA14-14-2 vaccine currently used to vaccinate against JE in the Republic of Korea (Group SA14-14-2). JE neutralizing antibody titers were assessed using PRNT50 before and 28 days after vaccination. The primary endpoint of non-inferiority of seroconversion rates on D28 was demonstrated in the Per Protocol analysis set as the difference between Group JE-CV and Group SA14-14-2 was 0.9 percentage points (95% confidence interval [CI]: -2.35; 4.68), which was above the required -10%. Seroconversion and seroprotection rates 28 days after administration of a single vaccine dose were 100% in Group JE-CV and 99.1% in Group SA14-14-2; all children except one (Group SA14-14-2) were seroprotected. Geometric mean titers (GMTs) increased in both groups from D0 to D28; GM of titer ratios were slightly higher in Group JE-CV (182 [95% CI: 131; 251]) than Group SA14-14-2 (116 [95% CI: 85.5, 157]). A single dose of JE-CV was well tolerated and no safety concerns were identified. In conclusion, a single dose of JE-CV or SA14-14-2 vaccine elicited a comparable immune response with a good safety profile. Results obtained in healthy Korean children aged 12-24 months vaccinated with JE-CV are consistent with those obtained in previous studies conducted with JE-CV in toddlers.

  15. Development of an in vitro antigen-detection test as an alternative method to the in vivo plaque reduction neutralization test for the quality control of Japanese encephalitis virus vaccine.

    Science.gov (United States)

    Kim, Do Keun; Kim, Hye-Youn; Kim, Joo-Young; Ye, Michael B; Park, Kee-Bum; Han, Euiri; Kim, Jaeok; Ja Ban, Sang; Hong, Seung Hwa; Park, Yong Keun; Nam, Jae-Hwan

    2012-07-01

    Japanese encephalitis virus (JEV) causes diseases that attack the human central nervous system. Traditionally, the quality control for JEV vaccines, in which the plaque reduction neutralization (PRN) titer is measured by the national control laboratories before the vaccine batches are marketed, has required laboratory animal testing. However, classical animal tests have inherent problems, including the very fact that animals are used, ethical issues, and the possibility of error. In this study, JEV antigen was measured in an in vitro assay to assess the feasibility of replacing in vivo assays that measure the PRN titers of JEV vaccines. We constructed a double-sandwich enzyme-linked immunosorbent assay (DS-ELISA) that could detect JEV envelope (E). Initially, monoclonal antibodies (mAbs) directed against the JEV E protein were generated and characterized. We isolated 18 mAbs against JEV E protein, and most were the IgG1 or IgG2a isotype. The mAbs (5F15 and 7D71) were selected as the most suitable mAb pair to detect JEV E protein. DS-ELISA with this pair detected as little as approximately 3 μg/mL JEV E protein and demonstrated a relationship between the amount of JEV E protein and the PRN titer. From these results, we surmise that this DS-ELISA may be useful, not only in terms of measuring the amount of JEV E protein, but also as a substitute for the PRN test for JEV vaccine evaluation.

  16. Genetic stability of a Vero-cell-derived, inactivated Japanese encephalitis vaccine (P3 strain)%乙型脑炎Vero细胞灭活疫苗毒株的遗传稳定性

    Institute of Scientific and Technical Information of China (English)

    张海燕; 曹晗; 王俊荣; 张名; 梁疆莉; 马艳; 顾琴; 杨卉娟; 孙明波

    2014-01-01

    Objective To investigate genetic stability of P3 strain of Vero cell derived inactivated Japanese encephalitis vaccine.Methods The nucleotide and amino acid sequences of E protein of Japanese encephalitis virus (JEV) P3 strain at different culture period including the mouse brain one passage seed,master seed,working seed the vaccine lot in addition to its 5 passages lot were determined,while the E gene and protein sequences were compared with JEV wide stain (AF036919) from the GenBank.Furthermore,the master seed,working seed,vaccine lot and its 5 passages lot of P3 stain were determined for virus titer,antigen concentration and the vaccine potency.Results The E gene and protein sequences of the above 5 passages of vaccine strain prepared for JEV vaccine showed no difference with homologies of 100%.When the 5 passages of vaccine stain compared with those JEV wide stain (AF036919),the gene sequence at E9,E10,E324,E330,E1223,E1338 showed difference with homologies of 99.73%.No silent mutation were investigated except the amino acid mutation at aE408 (L→S) but was no virulence-associated sites with homologies of 99.80%.The virus titers of the master seed,working seed,vaccine lot and its 5 passages lot of P3 stain were higher than 8.0 lgLD50/ml,while the antigen concentrations and the vaccine potency showed no difference.Conclusion The virus seed bank of P3 strain for Vero cell derived inactivated Japanese encephalitis vaccine showed high genetic stable.%目的 研究流行性乙型脑炎Vero细胞灭活疫苗毒种(P3毒株)在生产过程中的遗传稳定性,为疫苗的安全性和免疫原性评价提供依据.方法 检测P3毒株鼠脑传代一代毒株、主种子、工作种子、疫苗及疫苗续传5代后病毒E蛋白基因核苷酸及氨基酸序列,并与GenBank中乙脑病毒P3株(AF036919)进行比对分析,同时比较主种子、工作种子、疫苗及疫苗续传5代后毒株的病毒滴度、抗原含量及效价.结果 以上5代次病毒

  17. Dengue: a new challenge for neurology

    Directory of Open Access Journals (Sweden)

    Marzia Puccioni-Sohler

    2012-11-01

    Full Text Available Dengue infection is a leading cause of illness and death in tropical and subtropical regions of the world. Forty percent of the world’s population currently lives in these areas. The clinical picture resulting from dengue infection can range from relatively minor to catastrophic hemorrhagic fever. Recently, reports have increased of neurological manifestations. Neuropathogenesis seems to be related to direct nervous system viral invasion, autoimmune reaction, metabolic and hemorrhagic disturbance. Neurological manifestations include encephalitis, encephalopathy, meningitis, Guillain-Barré syndrome, myelitis, acute disseminated encephalomyelitis, polyneuropathy, mononeuropathy, and cerebromeningeal hemorrhage. The development of neurological symptoms in patients with positive Immunoglobulin M (IgM dengue serology suggests a means of diagnosing the neurological complications associated with dengue. Viral antigens, specific IgM antibodies, and the intrathecal synthesis of dengue antibodies have been successfully detected in cerebrospinal fluid. However, despite diagnostic advancements, the treatment of neurological dengue is problematic. The launch of a dengue vaccine is expected to be beneficial.

  18. Defining Hsp70 Subnetworks in Dengue Virus Replication Reveals Key Vulnerability in Flavivirus Infection.

    Science.gov (United States)

    Taguwa, Shuhei; Maringer, Kevin; Li, Xiaokai; Bernal-Rubio, Dabeiba; Rauch, Jennifer N; Gestwicki, Jason E; Andino, Raul; Fernandez-Sesma, Ana; Frydman, Judith

    2015-11-19

    Viral protein homeostasis depends entirely on the machinery of the infected cell. Accordingly, viruses can illuminate the interplay between cellular proteostasis components and their distinct substrates. Here, we define how the Hsp70 chaperone network mediates the dengue virus life cycle. Cytosolic Hsp70 isoforms are required at distinct steps of the viral cycle, including entry, RNA replication, and virion biogenesis. Hsp70 function at each step is specified by nine distinct DNAJ cofactors. Of these, DnaJB11 relocalizes to virus-induced replication complexes to promote RNA synthesis, while DnaJB6 associates with capsid protein and facilitates virion biogenesis. Importantly, an allosteric Hsp70 inhibitor, JG40, potently blocks infection of different dengue serotypes in human primary blood cells without eliciting viral resistance or exerting toxicity to the host cells. JG40 also blocks replication of other medically-important flaviviruses including yellow fever, West Nile and Japanese encephalitis viruses. Thus, targeting host Hsp70 subnetworks provides a path for broad-spectrum antivirals.

  19. The vector competence of colonized Aedes (Stegomyia) katherinensis for dengue-2 virus.

    Science.gov (United States)

    Leake, C J

    1984-01-01

    Colonized Aedes (Stegomyia) katherinensis mosquitoes from Australia were infected with the PR-159 strain of dengue-2 virus using a membrane feeding technique and by intrathoracic inoculation. Virus replication to low levels was detected when mosquitoes infected by both routes were assayed using the virus-sensitive Ae. pseudoscutellaris (LSTM-AP-61) mosquito cell line in a microculture system. Analysis by indirect immunofluorescence revealed the expected 100% infection rates in inoculated mosquitoes compared with only 45% in orally infected mosquitoes. Few of the orally infected mosquitoes showed any viral antigen associated with the head and no virus transmission was detected. Preliminary studies also demonstrated that Ae. (S.) katherinesis was refractory to oral infection with Japanese encephalitis virus but was readily infected by intrathoracic inoculation. On the basis of this data, it is concluded that there is a high threshold of infection in this mosquito and that it is unlikely that Ae. (S.) katherinensis could be important as a vector of dengue-2 virus in Australia.

  20. Limited cross-reactivity of mouse monoclonal antibodies against Dengue virus capsid protein among four serotypes

    Directory of Open Access Journals (Sweden)

    Noda M

    2012-11-01

    Full Text Available Megumi Noda,1 Promsin Masrinoul,1 Chaweewan Punkum,1 Chonlatip Pipattanaboon,2,3 Pongrama Ramasoota,2,4 Chayanee Setthapramote,2,3 Tadahiro Sasaki,6 Mikiko Sasayama,1 Akifumi Yamashita,1,5 Takeshi Kurosu,6 Kazuyoshi Ikuta,6 Tamaki Okabayashi11Mahidol-Osaka Center for Infectious Diseases, 2Center of Excellence for Antibody Research, 3Department of Microbiology and Immunology, 4Department of Social and Environmental Medicine, Faculty of Tropical Medicine, Mahidol University, Ratchathewi, Bangkok, Thailand; 5Graduate School of Life Science, Tohoku University, Sendai, Miyagi, 6Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, JapanBackground: Dengue illness is one of the important mosquito-borne viral diseases in tropical and subtropical regions. Four serotypes of dengue virus (DENV-1, DENV-2, DENV-3, and DENV-4 are classified in the Flavivirus genus of the family Flaviviridae. We prepared monoclonal antibodies against DENV capsid protein from mice immunized with DENV-2 and determined the cross-reactivity with each serotype of DENV and Japanese encephalitis virus.Methods and results: To clarify the relationship between the cross-reactivity of monoclonal antibodies and the diversity of these viruses, we examined the situations of flaviviruses by analyses of phylogenetic trees. Among a total of 60 prepared monoclonal antibodies specific for DENV, five monoclonal antibodies stained the nuclei of infected cells and were found to be specific to the capsid protein. Three were specific to DENV-2, while the other two were cross-reactive with DENV-2 and DENV-4. No monoclonal antibodies were cross-reactive with all four serotypes. Phylogenetic analysis of DENV amino acid sequences of the capsid protein revealed that DENV-2 and DENV-4 were clustered in the same branch, while DENV-1 and DENV-3 were clustered in the other branch. However, these classifications of the capsid protein were different from those of the

  1. Discriminant analysis on clinical characteristics of Japanese encephalitis and bacterial meningitis%乙型脑炎与细菌性脑膜炎临床指征判别分析

    Institute of Scientific and Technical Information of China (English)

    朱宇佳; 覃琼芬; 许超宇; 邓星超; 谢艺红; 吴兴华

    2011-01-01

    目的 分析乙型脑炎与细菌性脑膜炎病例实验室诊断与临床指征的特征,为提高疾病监测质量提供依据.方法 在广西贵港市进行症候群监测,捕获乙型脑炎、细菌性脑膜炎实验室确诊病例,进行临床体征、实验室常规监测等19项指标的单因素分析和判别分析.结果 监测疑似病例535例,捕获实验室确诊乙型脑炎38例和细菌性脑膜炎23例;判别分析结果显示,乙型脑炎预测符合率为84.21%(32/38),细菌性脑膜炎预测符合率为60.87%(14/23),总体预测符合率为75.41%(46/61);抽搐、脑脊液外观改变、脑脊液蛋白升高和葡萄糖减低等是细菌性脑膜炎的特征性临床指征,乙型脑炎则以抽搐为特异性临床指征;血常规白细胞计数和中性粒细胞比例等无明显诊断价值.结论 急性脑炎脑膜炎症候群的临床诊断准确率不高,存在一定程度漏报.%Objective To analyze clinical characteristics of bacterial meningitis and Japanese encephalitis(JE) for promoting the quality of the disease surveillance. Methods A surveillance system was established to capture the confirmed cases. Single factor analysis and discriminant analysis were conducted for 19 related indexes. Results A total of 535 suspected cases were evaluated in the surveillance, among which 38 and 23 cases were confirmed for JE and bacterial meningitis. Discriminant analyses yielded a JE confirrnation rate of 84. 21% ( 32/38 ) and a bacterial meningitis confirmation rate of 60. 87% ( 14/23 ) with a total validation accuracy rate of 75.41%. Convulsion, change of cerebrospinal fluid appearance, elevated cerebrospinal fluid protein, and glucose reduction were clinical indicators of bacterial meningitis. Blood leukocyte count and neutrophil ratio in peripheral blood were of no significant diagnostic value. Conclusion The clinical diagnostic accuracy was not high and there were unreported cases for acute encephalitis syndrome and meningitis.

  2. Dengue Fever Testing

    Science.gov (United States)

    ... AACC products and services. Advertising & Sponsorship: Policy | Opportunities Dengue Fever Testing Share this page: Was this page helpful? Also known as: Dengue Fever Antibodies; Dengue Fever Virus Formal name: Dengue ...

  3. 江西省流行性乙型脑炎病毒的分离与鉴定%Isolation and identification of Japanese encephalitis virus in Jiangxi province, China

    Institute of Scientific and Technical Information of China (English)

    李铭华; 付士红; 姜红月; 陈维欣; 唐松; 施勇; 梁国栋

    2012-01-01

    目的 调查江西省的虫媒病毒分布状况,在当地采集蚊虫标本进行病毒分离与鉴定.方法 2008-2009年夏季在江西省共选择8个标本采集点,使用诱蚊灯采集蚊虫标本,通过组织培养法分离病毒,并对病毒分离物进行血清学和分子生物学鉴定;利用生物信息学技术对新分离病毒的序列进行分析,完成同源性和系统发生分析.结果 2008年采集到3属3种共计11 916只蚊虫标本;2009年采集到4属5种共计5905只蚊虫标本;共分离到4株病毒,经鉴定均为流行性乙型脑炎(乙脑)病毒;新分离乙脑病毒与基因Ⅰ型乙脑病毒的同源性最高,系统进化结果显示,4株乙脑病毒均属于基因Ⅰ型.结论 在江西省分离到基因Ⅰ型乙脑病毒,与上海市和浙江省分离株进化关系较近.%Objective To investigate the distribution profiles of arboviruses in Jiangxi province, China. Methods Mosquito samples were collected using mosquito lamps at 8 sites in Jiangxi in the summers of 2008 and 2009 and then used for virus isolation by tissue culture. The obtained virus isolates were identified by serological and molecular biological methods. Homology and phylogenetic analysis was performed on the sequences of the isolates by bioinformatics. Results A total of 11 916 mosquitoes (3 species, 3 genera) were collected in 2008, and 5905 mosquitoes (5 species, 4 genera) were collected in 2009. Four virus strains were isolated from the mosquitoes and were all identified as Japanese encephalitis virus (JEV). All the JEV strains belong to genotype I , according to the homology and phylogenetic analysis. Conclusion Genotype I JEV strains were isolated from mosquitoes collected in Jiangxi province, China. And they have a close phylogenetic association with JEV strains from Shanghai and Zhejiang province, China.

  4. Growth characteristics of the chimeric Japanese encephalitis virus vaccine candidate, ChimeriVax-JE (YF/JE SA14--14--2), in Culex tritaeniorhynchus, Aedes albopictus, and Aedes aegypti mosquitoes.

    Science.gov (United States)

    Bhatt, T R; Crabtree, M B; Guirakhoo, F; Monath, T P; Miller, B R

    2000-04-01

    The Japanese encephalitis (JE) virus vaccine candidate, ChimeriVax-JE, which consists of a yellow fever (YF) 17D virus backbone containing the prM and E genes from the JE vaccine strain JE SA14--14--2, exhibits restricted replication in non-human primates, producing only a low-level viremia following peripheral inoculation. Although this reduces the likelihood that hematophagous insects could become infected by feeding on a vaccinated host, it is prudent to investigate the replication kinetics of the vaccine virus in mosquito species that are known to vector the viruses from which the chimera is derived. In this study ChimeriVax-JE virus was compared to its parent viruses, as well as to wild-type JE virus, for its ability to replicate in Culex tritaeniorhynchus, Aedes albopictus, and Aedes aegypti mosquitoes. Individual mosquitoes were exposed to the viruses by oral ingestion of a virus-laden blood meal or by intrathoracic (IT) virus inoculation. ChimeriVax-JE virus did not replicate following ingestion by any of the three mosquito species. Additionally, replication was not detected after IT inoculation of ChimeriVax-JE in the primary JE virus vector, Cx. tritaeniorhynchus. ChimeriVax-JE exhibited moderate growth following IT inoculation into Ae. aegypti and Ae. albopictus, reaching titers of 3.6-5.0 log(10) PFU/mosquito. There was no change in the virus genotype associated with replication in mosquitoes. Similar results were observed in mosquitoes of all three species that were IT inoculated or had orally ingested the YF 17D vaccine virus. In contrast, all mosquitoes either IT inoculated with or orally fed wild-type and vaccine JE viruses became infected, reaching maximum titers of 5.4-7.3 log(10) PFU/mosquito. These results indicate that ChimeriVax-JE virus is restricted in its ability to infect and replicate in these mosquito vectors. The low viremia caused by ChimeriVax-JE in primates and poor infectivity for mosquitoes are safeguards against secondary spread

  5. Histidine at residue 99 and the transmembrane region of the precursor membrane prM protein are important for the prM-E heterodimeric complex formation of Japanese encephalitis virus.

    Science.gov (United States)

    Lin, Ying-Ju; Wu, Suh-Chin

    2005-07-01

    The formation of the flavivirus prM-E complex is an important step for the biogenesis of immature virions, which is followed by a subsequent cleavage of prM to M protein through cellular protease to result in the production and release of mature virions. In this study, the intracellular formation of the prM-E complex of Japanese encephalitis virus was investigated by baculovirus coexpression of prM and E in trans in Sf9 insect cells as analyzed by anti-E antibody immunoprecipitation and sucrose gradient sedimentation analysis. A series of carboxyl-terminally truncated prM mutant baculoviruses was constructed to demonstrate that the truncations of the transmembrane (TM) region resulted in a reduction of the formation of the stable prM-E complex by approximately 40% for the TM1 (at residues 130 to 147 [prM130-147]) truncation and 20% for TM2 (at prM153-167) truncation. Alanine-scanning site-directed mutagenesis on the prM99-103 region indicated that the His99 residue was the critical prM binding element for stable prM-E heterodimeric complex formation. The single amino acid mutation at the His99 residue of prM abolishing the prM-E interaction was not due to reduced expression or different subcellular location of the mutant prM protein involved in prM-E interactions as characterized by pulse-chase labeling and confocal scanning microscopic analysis. Recombinant subviral particles were detected in the Sf9 cell culture supernatants by baculovirus coexpression of prM and E proteins but not with the prM H99A mutant. Sequence alignment analysis was further conducted with different groups of flaviviruses to show that the prM H99 residues are generally conserved. Our findings are the first report to characterize the minimum binding elements of the prM protein that are involved in prM-E interactions of flaviviruses. This information, concerning a molecular framework for the prM protein, is considered to elucidate the structure/function relationship of the prM-E complex

  6. Establishment of an Algorithm Using prM/E- and NS1-Specific IgM Antibody-Capture Enzyme-Linked Immunosorbent Assays in Diagnosis of Japanese Encephalitis Virus and West Nile Virus Infections in Humans.

    Science.gov (United States)

    Galula, Jedhan U; Chang, Gwong-Jen J; Chuang, Shih-Te; Chao, Day-Yu

    2016-02-01

    The front-line assay for the presumptive serodiagnosis of acute Japanese encephalitis virus (JEV) and West Nile virus (WNV) infections is the premembrane/envelope (prM/E)-specific IgM antibody-capture enzyme-linked immunosorbent assay (MAC-ELISA). Due to antibody cross-reactivity, MAC-ELISA-positive samples may be confirmed with a time-consuming plaque reduction neutralization test (PRNT). In the present study, we applied a previously developed anti-nonstructural protein 1 (NS1)-specific MAC-ELISA (NS1-MAC-ELISA) on archived acute-phase serum specimens from patients with confirmed JEV and WNV infections and compared the results with prM/E containing virus-like particle-specific MAC-ELISA (VLP-MAC-ELISA). Paired-receiver operating characteristic (ROC) curve analyses revealed no statistical differences in the overall assay performances of the VLP- and NS1-MAC-ELISAs. The two methods had high sensitivities of 100% but slightly lower specificities that ranged between 80% and 100%. When the NS1-MAC-ELISA was used to confirm positive results in the VLP-MAC-ELISA, the specificity of serodiagnosis, especially for JEV infection, was increased to 90% when applied in areas where JEV cocirculates with WNV, or to 100% when applied in areas that were endemic for JEV. The results also showed that using multiple antigens could resolve the cross-reactivity in the assays. Significantly higher positive-to-negative (P/N) values were consistently obtained with the homologous antigens than those with the heterologous antigens. JEV or WNV was reliably identified as the currently infecting flavivirus by a higher ratio of JEV-to-WNV P/N values or vice versa. In summary of the above-described results, the diagnostic algorithm combining the use of multiantigen VLP- and NS1-MAC-ELISAs was developed and can be practically applied to obtain a more specific and reliable result for the serodiagnosis of JEV and WNV infections without the need for PRNT. The developed algorithm should provide great

  7. A single N-linked glycosylation site in the Japanese encephalitis virus prM protein is critical for cell type-specific prM protein biogenesis, virus particle release, and pathogenicity in mice.

    Science.gov (United States)

    Kim, Jeong-Min; Yun, Sang-Im; Song, Byung-Hak; Hahn, Youn-Soo; Lee, Chan-Hee; Oh, Hyun-Woo; Lee, Young-Min

    2008-08-01

    The prM protein of Japanese encephalitis virus (JEV) contains a single potential N-linked glycosylation site, N(15)-X(16)-T(17), which is highly conserved among JEV strains and closely related flaviviruses. To investigate the role of this site in JEV replication and pathogenesis, we manipulated the RNA genome by using infectious JEV cDNA to generate three prM mutants (N15A, T17A, and N15A/T17A) with alanine substituting for N(15) and/or T(17) and one mutant with silent point mutations introduced into the nucleotide sequences corresponding to all three residues in the glycosylation site. An analysis of these mutants in the presence or absence of endoglycosidases confirmed the addition of oligosaccharides to this potential glycosylation site. The loss of prM N glycosylation, without significantly altering the intracellular levels of viral RNA and proteins, led to an approximately 20-fold reduction in the production of extracellular virions, which had protein compositions and infectivities nearly identical to those of wild-type virions; this reduction occurred at the stage of virus release, rather than assembly. This release defect was correlated with small-plaque morphology and an N-glycosylation-dependent delay in viral growth. A more conservative mutation, N15Q, had the same effect as N15A. One of the four prM mutants, N15A/T17A, showed an additional defect in virus growth in mosquito C6/36 cells but not human neuroblastoma SH-SY5Y or hamster BHK-21 cells. This cell type dependence was attributed to abnormal N-glycosylation-independent biogenesis of prM. In mice, the elimination of prM N glycosylation resulted in a drastic decrease in virulence after peripheral inoculation. Overall, our findings indicate that this highly conserved N-glycosylation motif in prM is crucial for multiple stages of JEV biology: prM biogenesis, virus release, and pathogenesis.

  8. DENGUE VACCINES.

    Science.gov (United States)

    Thisyakorn, Usa; Thisyakorn, Chule

    2015-01-01

    The uniqueness of the dengue viruses (DENVs) and the spectrum of disease resulting from infection have made dengue vaccine development difficult. Several vaccine candidates are currently being evaluated in clinical studies. The candidate currently at the most advanced clinical development stage, a live-attenuated tetravalent vaccine based on the chimeric yellow fever-dengue virus (CYD-TDV), has progressed to Phase 3 efficacy studies. Several other live-attenuated vaccines, as well as subunit, DNA, and purified inactivated vaccine candidates are at earlier stages of clinical development. Additional technological approaches, such as virus-vectored and Virus-Like Particles (VLP)-based vaccines are under evaluation in preclinical studies.

  9. Two Complex, Adenovirus-Based Vaccines That Together Induce Immune Responses to All Four Dengue Virus Serotypes▿

    OpenAIRE

    Holman, David H.; Wang, Danher; Raviprakash, Kanakatte; Raja, Nicholas U.; LUO, MIN; Zhang, Jianghui; Porter, Kevin R.; Dong, John Y.

    2006-01-01

    Dengue virus infections can cause hemorrhagic fever, shock, encephalitis, and even death. Worldwide, approximately 2.5 billion people live in dengue-infested regions with about 100 million new cases each year, although many of these infections are believed to be silent. There are four antigenically distinct serotypes of dengue virus; thus, immunity from one serotype will not cross-protect from infection with the other three. The difficulties that hamper vaccine development include requirement...

  10. 四川省流行性乙型脑炎病毒优势基因型的研究%Japanese encephalitis virus with genotype Ⅰ is predominant in Sichuan Province

    Institute of Scientific and Technical Information of China (English)

    张佳珂; 李伟; 胡梅; 梁国栋; 林世华; 周兴余; 陈丹林; 付士红; 刘学成; 袁伟; 曹一鸥; 王环宇

    2012-01-01

    Objective To understand molecular characteristics of Japanese encephalitis virus ( JEV ) isolated from the major Japanese encephalitis epidemic areas in Sichuan Province,and to provide the foundation for JEV prevention.Methods 13 JEV strains were isolated from mosquitoes in Sichuan during 2007-2010,E genes and preM genes were sequenced and phylogenetic analyses were performed using MEGA5 molecular software.Results Phylogeoetic analysis indicated that all 13 JEV strains from Sichuan belonged to genotype Ⅰ,homologies at nucleotide level and deduced amino acid level in PreM gene were 97%-100% and 98.7%-100%,and 97.8%-99.9% and 99.6%-100% in E gene,respectively.Homologies at nucleotide level and deduced amino acid level in PreM gene between 13 JEV strains and JEV isolated in 2004 in Sichuan were 96.2%-99.1% and 97.5%-98.7%,and were 97.7%-99.6% and 98.6%-100% in E gene,respectively.By comparison with vaacine strains P3 and SA14-14-2,homologies at nucleotide level and deduced amino acid level were 84.1%-85.8% and 93.7%-96.2% in PreM gene,and were 87.6%-88.3% and 97%-97.8% in E gene,respectively.The neurovirulence-related 8 amino acid sites encode by E gene remained unchanged in 13 JEV strains.Conclusion JEV with genotype Ⅰ predominated in Sichuan,nucleotide sequences and deduced amino acid sequences in PreM gene and E gene were highly conserved,key neurovirulence-rerlated sites remained unchanged.It suggested currently used vaccine is still capable of preventing JEV infection.%目的 了解四川省乙脑主要流行区乙脑病毒的分子生物学特性,为防治提供依据.方法 对2007—2010年间分离到的13株乙脑病毒进行PreM和E基因区扩增,采用MEGA5生物学软件完成氨基酸序列和病毒进化树分析.结果 基因分型显示13株均属于基因Ⅰ型.13株病毒之间比较,PreM基因核苷酸和氨基酸同源性为97%~100%和98.7%~100%,E基因核苷

  11. Dengue Epidemiology

    Science.gov (United States)

    ... Dengue is transmitted between people by the mosquitoes Aedes aegypti and Aedes albopictus , which are found throughout the world. Insects ... occurs every year, usually during a season when Aedes mosquito populations are high, often when rainfall is ...

  12. Dengue Returns

    Centers for Disease Control (CDC) Podcasts

    2016-08-25

    Dr. Tyler Sharp, a CDC epidemiologist, discusses dengue in southern Texas.  Created: 8/25/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 8/25/2016.

  13. Dengue Prevention

    Science.gov (United States)

    ... Address What's this? Submit What's this? Submit Button Prevention Recommend on Facebook Tweet Share Compartir This photograph ... medications to treat a dengue infection. This makes prevention the most important step, and prevention means avoiding ...

  14. Persistent West Nile Virus Transmission and the Apparent Displacement St. Louis Encephalitis Virus in Southeastern California, 2003−2006

    OpenAIRE

    REISEN, WILLIAM K.; Lothrop, Hugh D.; Wheeler, Sarah S.; KENNSINGTON, MARC; Gutierrez, Arturo; Fang, Ying; Garcia, Sandra; LOTHROP, BRANKA

    2008-01-01

    West Nile virus (family Flaviviridae, genus Flavivirus, WNV) invaded the Colorado Desert biome of southern California during summer 2003 and seemed to displace previously endemic St. Louis encephalitis virus (family Flaviviridae, genus Flavivirus, SLEV, an antigenically similar Flavivirus in the Japanese encephalitis virus serocomplex). Western equine encephalomyelitis virus (family Togaviridae, genus Alphavirus, WEEV), an antigenically distinct Alphavirus, was detected during 2005 and 2006, ...

  15. Mumps encephalitis with akinesia and mutism.

    Science.gov (United States)

    Suga, Kenichi; Goji, Aya; Shono, Miki; Matsuura, Sato; Inoue, Miki; Toda, Eiko; Miyazaki, Tatsushi; Kawahito, Masami; Mori, Kazuhiro

    2015-08-01

    Measles-rubella-mumps vaccination is routine in many countries, but the mumps vaccine remains voluntary and is not covered by insurance in Japan. A 5-year-old Japanese boy who had not received the mumps vaccine was affected by mumps parotitis. Several days later, he presented with various neurological abnormalities, including akinesia, mutism, dysphagia, and uncontrolled respiratory disorder. Mumps encephalitis was diagnosed. Despite steroid pulse and immunoglobulin treatment, the disease progressed. Magnetic resonance imaging showed necrotic changes in bilateral basal ganglia, midbrain, and hypothalamus. At 1 year follow up, he was bedridden and required enteral feeding through a gastric fistula and tracheostomy. Mumps vaccination should be made routine as soon as possible in Japan, because mumps encephalitis carries the risk of severe sequelae. © 2015 Japan Pediatric Society.

  16. Acute disseminated encephalomyelitis complicating dengue infection with neuroimaging mimicking multiple sclerosis: A report of two cases.

    Science.gov (United States)

    Viswanathan, S; Botross, N; Rusli, B N; Riad, A

    2016-11-01

    Acute disseminated encephalomyelitis (ADEM) complicating dengue infection is still exceedingly rare even in endemic countries such as Malaysia. Here we report two such cases, the first in an elderly female patient and the second in a young man. Both presented with encephalopathy, brainstem involvement and worsening upper and lower limb weakness. Initial magnetic resonance imaging (MRI) of the brain was normal in the first case. Serum for dengue Ig M and NS-1 was positive in both cases. Cerebrospinal fluid (CSF) showed pleocytosis in both with Dengue IgM and NS-1 positive in the second case but not done in the first. MRI brain showed changes of perpendicular subcortical palisading white matter, callosal and brainstem disease mimicking multiple sclerosis (MS) in both patients though in the former case there was a lag between the onset of clinical symptoms and MRI changes which was only clarified on reimaging. The temporal evolution and duration of the clinical symptoms, CSF changes and neuroimaging were more suggestive of Dengue ADEM rather than an encephalitis though initially the first case began as dengue encephalitis. Furthermore in dengue encephalitis neuroimaging is usually normal or rarely edema, haemorrhage, brainstem, thalamic or focal lesions are seen. Therefore, early recognition of ADEM as a sequelae of dengue infection with neuroimaging mimicking MS and repeat imaging helped in identifying these two cases. Treatment with intravenous steroids followed by maintenance oral steroids produced good outcome in both patients. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Development of real time PCR for detection and quantitation of Dengue Viruses

    Directory of Open Access Journals (Sweden)

    Singh A

    2009-01-01

    Full Text Available Abstract Background Dengue virus (DENV, a mosquito borne flavivirus is an important pathogen causing more than 50 million infections every year around the world. Dengue diagnosis depends on serology, which is not useful in the early phase of the disease and virus isolation, which is laborious and time consuming. There is need for a rapid, sensitive and high throughput method for detection of DENV in the early stages of the disease. Several real-time PCR assays have been described for dengue viruses, but there is scope for improvement. The new generation TaqMan Minor Groove Binding (MGB probe approach was used to develop an improved real time RT-PCR (qRT-PCR for DENV in this study. Results The 3'UTR of thirteen Indian strains of DENV was sequenced and aligned with 41 representative sequences from GenBank. A region conserved in all four serotypes was used to target primers and probes for the qRT-PCR. A single MGB probe and a single primer pair for all the four serotypes of DENV were designed. The sensitivity of the two step qRT-PCR assay was10 copies of RNA molecules per reaction. The specificity and sensitivity of the assay was 100% when tested with a panel of 39 known positive and negative samples. Viral RNA could be detected and quantitated in infected mouse brain, cell cultures, mosquitoes and clinical samples. Viral RNA could be detected in patients even after seroconversion till 10 days post onset of infection. There was no signal with Japanese Encephalitis (JE, West Nile (WN, Chikungunya (CHK viruses or with Leptospira, Plasmodium vivax, Plasmodium falciparum and Rickettsia positive clinical samples. Conclusion We have developed a highly sensitive and specific qRT-PCR for detection and quantitation of dengue viruses. The assay will be a useful tool for differential diagnosis of dengue fever in a situation where a number of other clinically indistinguishable infectious diseases like malaria, Chikungunya, rickettsia and leptospira occur. The

  18. Allergic reactions to Japanese encephalitis vaccine.

    Science.gov (United States)

    Plesner, Anne-Marie

    2003-11-01

    The JEV widely is used in Asian countries each year and is an important vaccine for travelers to the East from other parts of the world. JE virus is a zoonotic disease with natural reservoirs and cannot be eliminated. Although a declining incidence of JE has been observed in Asia because of reduced transmission by agricultural approaches and vaccination, the most important control measure now, and in the future, is vaccination of humans against JE. The inactivated vaccine, produced from infected mouse-brain-derived tissue, is the only commercially available vaccine. There are several concerns with the use of this vaccine. It is expensive, requires two or three doses to achieve protective efficacy, and, in practice, requires further booster doses to maintain immunity. The apparent increase in allergic reactions in the first part of the 1990s has set focus on the safety of the JEV. A cheap, live attenuated SA 14-14-2 vaccine is used almost exclusively in China and parts of Korea, but there have been no trials of SA 14-14-2 vaccine outside JE endemic countries. The vaccine seems to be highly efficient, and few adverse events have been observed; however, PHK cells are used for the production of this vaccine, and these cells are not approved by the WHO. A satisfactory cell substrate is needed. A committee under the WHO has proposed that for the live JEV, there should be validity of the assays for retrovirus when applied to PHK cell substrate and validity of the mouse assays for neurovirulence. Further information should be reviewed on the long-term follow-up of recipients of the vaccine. Several new types of vaccines have reached the phase of clinical trials; however, studies remain to be completed. Until a new vaccine is available, the priority of surveillance of adverse events and the continuous reporting of such events to the users of the vaccines must be of importance. This fact is highlighted by the possibility of the varying frequency of adverse events with different batches over the years. The WHO offers information and recommendations for vaccines in the EPI and issues a series of updated papers on other vaccines that are of international public health importance (eg, JEV). The development of alternative efficient, safe, and appropriately priced JEVs is recommended, as is intensified surveillance of adverse events. Prospective vaccine studies of safety may be limited because of sample size and because rare adverse events may not be detected. Several new initiatives have been taken to improve surveillance of adverse events to vaccines within the past 10 years. In Japan, there is an increasing awareness of the importance of efforts taken to improve vaccine safety, and surveillance of adverse events and possibilities of compensation for vaccine-related injuries are in place. In Vietnam, a database to detect adverse events after vaccination has been established; the project involves active visits to data collectors at the vaccination sites. Comparative studies of adverse events, such as one recent study from Japan and the United States, are important for the evaluation of the reporting systems. The reporting rate for JEV adverse events from Japan was approximately one order of magnitude lower than that in the United States. Japan had strict predefined reporting criteria and time limits for observations. If time limits for the observation are too strict (eg, defining a possible neurologic reaction to occur within 1 week after vaccination), later reactions will not be included (eg, if ADEM is elicited by a vaccine, the symptoms cannot be expected to occur until weeks after the vaccination). The passive surveillance systems have limitations with an underreporting of adverse events, depending on clinical seriousness, temporal proximity to vaccination, awareness of healthcare workers, and tradition of reporting particular events. In developed countries, surveillance of adverse events is formalized, although not necessarily optimal. An increase in reporting would be expected when the reporting of adverse events is mandatory. Reports have been sent to VAERS, the Vaccine Safety Datalink Project, and the European Union Pharmacovigilance System. A Brighton collaboration has been implemented to enhance comparability of vaccine safety data. Public health authorities in specific countries, such as the CDC in the United States and the National Advisory Committee in Canada, regularly have published information on the JE situation in Asia and the preventive measures to be taken, including information on the vaccines and adverse reactions. The conventional recommendation is that travelers should be vaccinated if they will spend more than 1 month in a JE endemic area or in areas with epidemic transmission with even shorter periods. Although the risk for JE for short-term travelers is considered small (1 case per 1 million travelers per year), sporadic cases, including deaths, have been reported among tourists traveling to endemic areas. Risk for travelers in rural districts in the season of risk is considerably higher (range, 1 case per 5000 travelers to 1 case per 20,000 travelers per week). Doctors who advise travelers should be updated on the latest JE occurrences in Asia. Updates on the JE situation can be found on bulletins at http://www.promedmail.org or are available from the WHO or CDC. The allergic reactions primarily described after vaccination with the inactivated mouse-brain-derived JEV have been observed in several countries during the 1900s. Allergic reactions, including the mucocutaneous and neurologic reactions reported after JE vaccination, may vary in frequency, and these reactions should be evaluated meticulously yearly. This step enables recommendations, including information on possible side effects, to be given in an optimal way.

  19. Biomarkers in Japanese Encephalitis: A Review

    Science.gov (United States)

    Kant Upadhyay, Ravi

    2013-01-01

    JE is a flavivirus generated dreadful CNS disease which causes high mortality in various pediatric groups. JE disease is currently diagnosed by measuring the level of viral antigens and virus neutralization IgM antibodies in blood serum and CSF by ELISA. However, it is not possible to measure various disease-identifying molecules, structural and molecular changes occurred in tissues, and cells by using such routine methods. However, few important biomarkers such as cerebrospinal fluid, plasma, neuro-imaging, brain mapping, immunotyping, expression of nonstructural viral proteins, systematic mRNA profiling, DNA and protein microarrays, active caspase-3 activity, reactive oxygen species and reactive nitrogen species, levels of stress-associated signaling molecules, and proinflammatory cytokines could be used to confirm the disease at an earlier stage. These biomarkers may also help to diagnose mutant based environment specific alterations in JEV genotypes causing high pathogenesis and have immense future applications in diagnostics. There is an utmost need for the development of new more authentic, appropriate, and reliable physiological, immunological, biochemical, biophysical, molecular, and therapeutic biomarkers to confirm the disease well in time to start the clinical aid to the patients. Hence, the present review aims to discuss new emerging biomarkers that could facilitate more authentic and fast diagnosis of JE disease and its related disorders in the future. PMID:24455705

  20. Viral meningitis and encephalitis.

    Science.gov (United States)

    Tuppeny, Misti

    2013-09-01

    Meningitis is an inflammation of the meninges, whereas encephalitis is inflammation of the parenchymal brain tissue. The single distinguishing element between the 2 diagnoses is the altered state of consciousness, focal deficits, and seizures found in encephalitis. Consequently meningoencephalitis is a term used when both findings are present in the patient. Viral meningitis is not necessarily reported as it is often underdiagnosed, whereas encephalitis cases are on the increase in various areas of North America. Improved imaging and viral diagnostics, as well as enhanced neurocritical care management, have improved patient outcomes to date.

  1. 甘肃省及河西走廊地区乙型脑炎疫区变迁分析%Epidemic area and geographic distribution of Japanese encephalitis in Gansu province

    Institute of Scientific and Technical Information of China (English)

    王旭霞; 王平贵; 王芳; 张晓曙; 李慧

    2013-01-01

    目的 分析甘肃省及河西走廊地区乙型脑炎(乙脑)疫区变迁趋势,探讨甘肃省乙脑重点防控区及河西走廊地区乙脑疫情特征.方法 利用甘肃省疾病预防控制中心1958-2010年疫情资料和法定传染病报告系统资料,运用描述流行病学方法和局部地区调查,分析1980年开始使用乙脑疫苗前后甘肃省乙脑发病率和疫区地理分布变化及河西走廊地区乙脑疫情.结果 1958-1980年,甘肃省乙脑年均发病率为0.65/10万;1980年开始推广使用乙脑疫苗,到2010年,发病降至0.13/10万,未出现乙脑较大流行;发病率较高的县(市、区)分布于甘肃省陇南市、天水市和平凉市,发病趋势与全省平均发病趋势基本一致,是甘肃省乙脑防控的重点地区;1958-1980年,河西走廊累计报告乙脑病例88例,年均发病率为0.13/10万,1981年以来,仅张掖市甘州区报告1例非本地发病乙脑病例;2011年8月调查河西走廊地区7个县(区、市)县级以上医院的住院病例,共发现疑似脑炎病例587例.结论 甘肃省在使用乙脑疫苗后,乙脑发病水平明显降低,东南部地区是甘肃省乙脑重点防控区,河西走廊是否存在乙脑病例尚需进一步调查并进行全面监测.%Objective To analyze changing trend of Japanese encephalitis (JE) epidemic in Gansu province and Hexi Corridor and to examine the characteristics of JE epidemic in Hexi Corridor.Methods The data of field study and surveillance on JE in Gansu from 1958 to 2010 from National Notifiable Disease Reporting System were abstracted to analyze the changes in incidence and regional distribution of JE in Hexi Corridor before and after immunization of JE vaccine using descriptive epidemiology methods.Results From 1958 to 1980,the average annual incidence of JE was 0.65/100 000 in Gansu.There was no epidemic of JE in Gansu after JE vaccination in 1980 and the incidence of JE in 2010 dropped to 0.14/100 000.The areas at higher risk

  2. Isolation and identification of Japanese encephalitis virus in Tanghe county, Henan Province%河南省唐河县分离到基因1型乙型脑炎病毒

    Institute of Scientific and Technical Information of China (English)

    王环宇; 唐青; 梁国栋; 郝宗宇; 付士红; 张爱梅; 曹玉玺; 宋付党; 李林红; 何英; 王焕琴

    2008-01-01

    Objective To isolate Japanese encephalitis virus (JEV) from mosquitoes collected in Tanghe county, Henan province and analyze the genotype of the newly isolated JEV strains and the characteristics of amino acid in the E gone. Methods Viruses were isolated from mosquitoes collected in 2004 and identified by biological, serological and molecular biological methods. PrM and E segments of the newly isolated JEV were amplified by RT-PCR, the PCR products were purified and sequenced. Multiple alignment, phylogenetic and amino acid (AA) analysis were carried out by Clustal X (1.8) program, MEGA 3.1 and GENEDOS (3.2).Results Totally 3722 mosquitoes were collected including Culex, Armigeres, Aedes, Anopheline. Three new JEV strains isolated from Cutex belonged to genotype 1. The homologue of nucleotide and amino acid of E gene between new JEV strains and live attenuated vaccine strain SA14-14-2 was 86.9%-87.7% and 95.2%-97.0%,respectively. Totally there were 12 common sites of amino acid differences in E gene between them. Conclusion Newly isolated viruses in Henan province belonged to JEV genotype 1. It suggests that the vaccine strain SA14-14-2 currently used for preventing JE is able to protect people from JEV infection, although there are some amino acid differences between them.%目的 从河南省唐河县采集的蚊虫标本中分离乙型脑炎病毒(JEV)并确定其基因分型及E基因区段氨基酸序列特征.方法对2004年采集蚊虫标本进行病毒分离,对新分离的乙脑病毒进行生物学、血清学及分子生物学鉴定.逆转录聚合酶链反应(RT-PCR)扩增新分离JEV的PrM、E区段核苷酸序列,测序后应用Clustal X软件做碱基配对分析,MEGA3.1完成病毒进化分析,GENEDOS(3.2)软件完成氨基酸位点分析.结果共采集3722只蚊虫标本,包括:库蚊、骚扰阿蚊、伊蚊及按蚊.从库蚊标本中分离到3株属于基因1型的乙脑病毒,E区段核苷酸和氨基酸与减毒活疫苗株SA14-14-2

  3. Epidemiology of Japanese encephalitis in Ningbo city in Zhejiang province ,2005-2010%2005-2010年浙江省宁波市流行性乙型脑炎流行病学分析

    Institute of Scientific and Technical Information of China (English)

    方挺; 郭延波; 潘兴强; 马瑞; 张栋梁; 周绍英

    2012-01-01

    Objective To analyze Che epidemiological characteristics of Japanese encephalitis (JE) in Ningbo from 2005 to 2010 and provide scientific evidence for the disease prevention and control in the future. Methods The analysis was conducted on the surveillance data of JE in Ningbo during this period. Results A total of 136 JE cases were reported, including 16 deaths. The average annual incidence and case fatality were the scattered 0.40/lakh and 11. 76% respectively, the incidence was highest in 2006 (0. 80/lakh) and lowest in 2010 (0. 12/lakh). The seasonality of the disease was obvious, and the cases mainly occurred during June-September with the incidence peak in July. The majority of cases were the scattered children in rural population and in floating population. (52. 94% ), the youngest was only 2 months old. Totally 8. 82% of the cases occurred in people aged > 15 years, the oldest was 77 years old. Conclusion It is necessary to strengthen JE vaccination, improve environment sanitation and conduct health education in rural area and in zone joining urban and rural areas with dense floating population to improve herd immunity and prevent/control JE effectively.%目的 分析探讨宁波市2005 -2010年流行性乙型脑炎(乙脑)的流行病学特征,为制定乙脑预防控制措施提供参考依据.方法 收集和分析2005-2010年宁波市乙脑疫情监测资料.结果 宁波市2005-2010年报告乙脑确诊病例136例,死亡16例,年平均发病率0.4/10万,病死率11.76%,其中2006年发病率最高为0.80/10万,2010年最低为0.12/10万;发病呈明显的季节性,集中在6-9月,7月最多;发病者多为农村及外来流动的散居儿童,占总发病数的52.94%,其中年龄最小为2月龄;15岁以上病例占总病例数的8.82%,其中年龄最大为77岁.结论 宁波市乙脑疫情总体情况良好,但乙脑防制工作需重视流动人口居住地农村及城乡结合部,应加强外来流动儿童的免疫接种、防蚊灭蚊和

  4. 浙江省蚊虫中乙型脑炎病毒的分离及鉴定%Isolation and identification of Japanese encephalitis virus from mosquitoes in Zhejiang province

    Institute of Scientific and Technical Information of China (English)

    谢荣辉; 付士红; 程胤凯; 徐芳; 姚苹苹; 翁景清; 朱函坪; 张意坚; 朱智勇

    2008-01-01

    Objective To study the situation of arboviruses carried by mosquitoes in Zhejiang province.Methods Mosquitoes were collected from Zhejiang province in 2007.Virus strains were isolated by the inoculation of homogenates of the mosquitoes onto BHK-21 cell line.The isolated strains were identified by serological(IFA)and molecular methods(RT-PCR).Results Two strains were isolated from mosquitoes causing cytopathogenic effect(CPE)in BHK-21 cells.Results from serological tests showed that both of the two strains were positive for the antibody to Japanese encephalitis virus(JEV).PrM and E gene were then cloned and sequenced.Results from the phylogenetic analysis showed that the isolates belonged to genotype Ⅰ JEV while through sequence analysis it showed that the homology of nucleotide sequences and amino acid sequences between the two strains were 99.0% and 98.8% respectively.Compared with the JEV vaccine strain SA14-14-2 and two strains,the homology of nucleotide sequences Was up to 87.7% and homology of amino acid sequences was up to 96.4%.When comparing with the vaccine strain SA14-14-2,there were 14 common amino acid variations in all the two strains.Conclusion Two strains of JEV were isolated from mosquitoes collected in Zhejiang province whiCh was the first isolation of genotype Ⅰ JEV in the province in recent years.%目的 对2007年浙江省采集的蚊虫标本进行病毒分离与鉴定.方法 2007年在浙江省采集蚊虫标本,用金黄地鼠肾细胞(BHK-21)分离病毒,对新分离的病毒进行血清学和分子生物学鉴定.结果 采集到4735只蚊虫,分离到2株致BHK-21细胞病变的病毒,经免疫荧光和RT-PCR试验鉴定为乙型脑炎病毒(JEV),利用病毒PrM区段进行基因分型分析,新分离的2株病毒属于基因Ⅰ型JEV.对这2株病毒的E基因区段进行分析,核苷酸和氨基酸的同源性分别为99.0%和98.8%.与疫苗株SA14-14-2相比,核苷酸同源性在87.7%,氨基酸同源性在96.4%以上,共有14个共

  5. 贵州省流行性乙型脑炎疫苗强化免疫成本效益评价%Cost-effectiveness evaluation on Japanese Encephalitis Live Attenuated Vaccine Mass Immunization Campaign in Guizhou

    Institute of Scientific and Technical Information of China (English)

    张丽; 詹玮; 蒋凤; 芮丽萍; 刘铭; 刁壁; 尹遵栋; 李艺星; 罗会明

    2012-01-01

    OBJECTIVE To review the economic benefits of Japanese Encephalitis ( JE) live attenuated vaccine mass campaign in Guizhou province. METHODS Data from the sampling were analyzed by cost—effectiveness analysis to investigate the expenditure of hospitalization and non—hospital treatment, chaperone costs and re—habilitation costs. The per capita Gross Domestic Product was created by the nursing personnel of JE cases as well as the expenditure, which was essential for controlling JE. The index DALY, which was commonly applied internationally at present, was utilized to calculate the loss of death and disability caused by the incidence of JE quantitatively. Also, the ratio of cost-effectiveness and net benefits produced were counted. RESULTS After JE live attenuated vaccine mass immunization campaigns, the annual average incidence rate of JE in Guizhou province decreased by 65.30% than 1990-2006. Meanwhile, the reduced loss of incidence, disability and death amount to 843.6 thousand Yuan. The net benefits produced were 125.20 million Yuan and the rate of cost-effectiveness was 1: 4.88. CONCLUSION All of the data indicate that the incidence of JE decreased remarkably after the mass immunization campaign with JE live attenuated vaccine. The measure of preventing JE by using JE live attenuated vaccine is economical and effectively.%目的 探讨贵州省实施流行性乙型脑炎(乙脑)疫苗强化免疫的成本效益.方法 抽样调查乙脑病例住院和非住院治疗费用、陪护费用、康复费用以及乙脑疫苗强化免疫工作中需投入的经费.计算因乙脑患病陪护人员人均减少的产值,用伤残调整寿命年指标(DALY)计算因乙脑发病造成的死亡和伤残损失,采用成本-效益分析方法,计算乙脑强化免疫的成本效益比值和产生的净效益.结果 1例乙脑病例患病后社会减少产值84.36万元.贵州省2007年开展乙脑疫苗强化免疫后发病率较1990~2006年强化前平均下降了65

  6. Prokaryotic expression and subcellular localization of Japanese encephalitis virus NS5 protein%乙型脑炎病毒NS5蛋白原核表达与亚细胞定位研究

    Institute of Scientific and Technical Information of China (English)

    栗永茂; 曹胜波; 陈龙; 霍雨艳; 熊涛; 吴光旭

    2011-01-01

    The NS5 gene of Japanese encephalitis virus was amplified by PCR and cloned into the prokaryotic expression vector pET-28a. The recombinant NS5 protein was expressed highly under induction of IPTG in the E. Coli. Using BALB/c female mice immuned with the purified recombinant NS5 protein, NS5 protein-specific polyclonal antibody were prepared. Meanwhile, BHK-21 cells were transfected with eukaryotic expression plasmid pcDNA-NS5-EGFP of NS5 gene and green fluorescent protein (EGFP) fusion expression. Finally, the subcellular localization of NS5 protein in BHK-21 cells was observed by using laser confocal fluorescence microscope. The result indicates that the protein particles are irregularly distributed in the whole cell and particularly in the cytoplasm.%目的 对乙型脑炎病毒NS5蛋白进行原核表达和亚细胞定位研究.方法 通过PCR扩增乙型脑炎病毒NS5基因,并将之克隆至原核表达载体pET-28a(+)中,构建的重组表达载体转化大肠杆菌感受态细胞,经IPTG诱导表达目的蛋白.将表达产物纯化后,免疫BALB/c小鼠,制备NS5蛋白特异性的多克隆抗体.同时,构建NS5基因与绿色荧光蛋白(EGFP)融合表达的真核表达质粒pcDNA-NS5-EGFP,将之转染BHK-21细胞,利用激光共聚焦荧光显微镜观察NS5蛋白在BHK-21细胞中的亚细胞定位.结果 NS5蛋白在大肠杆菌中获得了高效表达,表达蛋白分子量大小约为103kD,该蛋白在真核细胞中的表达呈颗粒状不均匀分布于整个细胞,且颗粒状主要分布在细胞质中.结论 成功表达乙型脑炎病毒NS5蛋白,并对NS5蛋白的亚细胞定位进行了分析,为进一步研究NS5蛋白提供依据.

  7. Screening and application of epitope in glycoprotein E of Japanese encephalitis vi-rus%日本乙型脑炎病毒E抗原表位的筛选与鉴定

    Institute of Scientific and Technical Information of China (English)

    马丽敏; 李琳; 任秀梅; 李晔; 何叶; 靳朝; 夏志平; 王本旭

    2012-01-01

    筛选日本乙型脑炎病毒(JEV)的E抗原表位,为开展用JEV模拟表位探索JEV的防治研究创造了条件,为多肽疫苗研制、药物筛选以及特异血清学诊断方法的建立提供重要的线索和依据。以抗JEvE蛋白的单克隆抗体作为固相筛选分子,应用噬菌体表面展示技术,按消减、结合、洗脱、扩增的顺序筛选噬菌体7肽库,挑取噬菌体单克隆培养并ELISA鉴定,对阳性克隆测序分析,确定JEVE抗原模拟表位的氨基酸序列。设计合成包含该表位的E抗原15肽(GGADSMSMAGMAVSY)cDNA序列,与pGEX-KG构建重组表达载体,诱导表达重组多肽并west-ernblot验证。经过4轮筛选后,噬菌体得到高度富集,挑取单克隆ELISA鉴定,有22个克隆呈阳性。对重组多肽进行Western blot验证,结果表明该重组多肽能够特异结合兔抗JEV多抗。应用上述方法成功筛选出JEV结构蛋白E的特异性噬菌体模拟表位,为下一步研究奠定了基础。%Screening E-epitope of Japanese encephalitis virus (JEV), creating the conditions for JEV prevention and treatment research by mimotope,providing important clues and basis for establishing specific serological diagnostic methods and exploring peptide vaccine of JEV. With the monoclonal antibody molecules of JEV E protein as solid phase screening, screening the phage heptapeptide library by a rule of reduction, combined, elution, amplification. Picked monoclonal phages and detect them by ELISA, the positive clones were sequenced. Designed and synthesised a cDNA sequence with 15 peptides (GGADSMSMAGMAVSY) and conducted a recombinant expression vector with pGEX-KG,induced to express the recombinant polypeptide and dectected it by Western blot. Phages were highly en- riched after four rounds of screening, it is proved that there were 22 positive clones by ELISA. The Western blot show that the recombinant polypeptide can bind to rabbit polyelonal anti

  8. Molecular characterization of complete genome of Japanese encephalitis virus HEN0701 strain isolated from swine%猪源乙型脑炎病毒HEN0701株全基因组的分子特征

    Institute of Scientific and Technical Information of China (English)

    郑浩; 孙春清; 袁世山

    2011-01-01

    Four overlapping cDNA fragments from Japanese encephalitis virus(JEV) HEN0701 strain were cloned into pCR Ⅱ-Blunt-TOPO vector, followed by determination of complete genomic cDNA sequence. The complete genome of HEN0701 strain was 10 965 nucleotides in length,including a long open reading frame from 97th to 10395th nucleotide in the genome. Comparing to 6 strains of genotype Ⅰ (G Ⅰ)JEV and 5 strains of G Ⅲ, HEN0701 had high nucleotide sequence identity with G Ⅰ strains, but low nucleotide sequence identity with G Ⅲ strains in both complete genome and each gene. However, HEN0701 had high amino acid sequence identity with both G Ⅰ and GⅢ strains in both full polyprotein and each viral protein. Phylogenetic trees based on the C,E,NS3 and NS5 gene sequences of HEN0701 and 11 JEV strains were constructed with the software MEGA 5. Four phylogenetic trees had similar topology,indicating that the four genes from JEV had the similar evolutionary trend.%将乙型脑炎病毒HEN0701株基因组RNA分4段进行RT-PCR扩增,并克隆入pCRⅡ-Blunt-TOPO载体中,测定全长cDNA序列.以MapDraw软件分析了乙型脑炎病毒HEN0701株的基因组结构,并将病毒基因组分成2个非编码区和10个基因,比较了HEN0701株和11株乙型脑炎病毒在全基因组和各基因的核苷酸及推导氨基酸的同源性.以MEGA5软件绘制HEN0701株和11株病毒C、E、NS3、NS5 基因的进化树.结果显示,HEN0701株全基因组为10965 nt,包含一长10299 nt的开放阅读框.在核苷酸水平,HEN0701株与GⅠ分离株的全基因组和各基因的同源性均高,而与GⅢ分离株则较低;而在氨基酸水平,HEN0701株与GⅠ分离株在多聚蛋白和各病毒蛋白的同源性和HEN0701株与GⅢ分离株的相近.进化分析显示,不同基因进化树的拓扑结构相近,12株病毒的C、E、NS3、NS5基因进化方向相同,GⅠ分离株和GⅢ分离株间C基因进化距离最近.

  9. Dengue perinatal

    Directory of Open Access Journals (Sweden)

    Doris Martha Salgado

    2013-08-01

    Full Text Available El dengue es en la actualidad la enfermedad viral más relevante de transmisión vectorial hiperendémica en las Américas. El incremento en el número de casos se ha relacionado con la aparición de dengue durante la gestación y en el periodo neonatal. De acuerdo con la edad de gestación en la que ocurra la infección, podrían presentarse manifestaciones en el feto, como aborto, y en los pacientes a término,dengue neonatal. En este artículo se presenta una reseña de los casos reportados a nivel mundial, y especialmente en las Américas, así como aspectos fisiopatogénicos de la enfermedad.   doi: http://dx.doi.org/10.7705/biomedica.v33i0.1449

  10. Chimeric Yellow Fever/Dengue Virus as a Candidate Dengue Vaccine: Quantitation of the Dengue Virus-Specific CD8 T-Cell Response

    OpenAIRE

    van der Most, Robbert G.; Murali-Krishna, Kaja; Ahmed, Rafi; Strauss, James H.

    2000-01-01

    We have constructed a chimeric yellow fever/dengue (YF/DEN) virus, which expresses the premembrane (prM) and envelope (E) genes from DEN type 2 (DEN-2) virus in a YF virus (YFV-17D) genetic background. Immunization of BALB/c mice with this chimeric virus induced a CD8 T-cell response specific for the DEN-2 virus prM and E proteins. This response protected YF/DEN virus-immunized mice against lethal dengue encephalitis. Control mice immunized with the parental YFV-17D were not protected against...

  11. Tick-Borne Encephalitis (TBE)

    Science.gov (United States)

    ... Search The CDC Cancel Submit Search The CDC Tick-borne Encephalitis (TBE) Note: Javascript is disabled or ... CDC.gov . Recommend on Facebook Tweet Share Compartir Tick-borne encephalitis, or TBE, is a human viral ...

  12. A rare case of dengue encephalopathy complicating a term pregnancy.

    Science.gov (United States)

    Rajagopala, Lavanya; Satharasinghe, Ravindra L; Karunarathna, Madhava

    2017-02-02

    Dengue fever has an expanded clinical spectrum ranging from an asymptomatic infection to life threatening dengue hemorrhagic fever and refractory shock. Dengue infection in pregnancy can be a diagnostic dilemma, particularly considering the physiological changes in pregnancy and the obstetric complications encountered in clinical practice. Hence the knowledge of its diagnosis and management in its atypical presentations is of paramount importance. Here we report an unusual case of uncomplicated dengue encephalopathy in a term mother, probably the first to be reported from the Indian subcontinent. A 28 year old woman, 37 weeks of pregnancy presented with fever of four days duration. She eventually developed irritability, altered sensorium, somnolence, and unresponsiveness to commands by the 5th day of febrile illness without any circulatory compromise. Physical examination and investigations including serology confirmed dengue fever. After excluding all other possible causes, the transient neurological deterioration was finally attributed to dengue encephalopathy which is an uncommon manifestation of the disease, particularly in pregnancy. Her deteriorated neurological status which had lasted for 6 days improved spontaneously with the convalescence of dengue infection. Cautious fluid management was carried out in correlation to clinical and hematological parameters. The pregnancy was continued uncomplicated till the platelet count had risen to more than 50,000 cells/cumm. She delivered vaginally a healthy male baby. Dengue fever in pregnancy is increasingly being encountered due to its rising disease burden. Dengue encephalitis/encephalopathy must be suspected in the differential diagnosis of fever and altered sensorium, even in pregnancy, in the tropical countries where the infection is rampant. Management of dengue infection in term pregnancy is a challenge for both the clinician and obstetrician. Further discussion and research are mandatory to decide on

  13. DUAL INFECTION OF SWINE PSEUDORABIES VIRUS AND JAPANESE ENCEPHALITIS VIRUS IN PIGS%猪群混合感染伪狂犬病毒及乙型脑炎病毒的鉴定与分离

    Institute of Scientific and Technical Information of China (English)

    刘宁; 宋聪; 高林; 谢佳芮; 李华春; 王静林; 姚俊; 王生奎

    2016-01-01

    A reproductive disease with clinical manifestations of boar testicle swelling, sow abortion, stillbirth, mummy and weak off spring occurred on a large-scale pig farm from July to August of 2015 in city of Wenshan, Yunnan province.In order to identify the etiological agent(s), CSFV, PRRSV (American/EU type/), PPV, PRV, JEV,Chlamydia psittaci,Toxoplasma gondii,Brucella suis were examined using PCR, real-time PCR and bacterial isolation. As a result, 600 bp fragments of PrM gene of JEV and 810 bp fragments of gE gene of PRV were amplified in RT-PCR or PCR. Sequence analysis showed that the homology of nucleotide sequences of the amplicons was 99% with the reference strains of JEV (Accession:AB594829.1) and 100% with PRV (Accession:KT936475.1) from GenBank. In addition, primary pig kidney cells and BHK21 cells were used for virus isolation. One virus isolate of JEV was obtained from aborted fetal tissue and designated as JEV-2015-WS-YN. Although PRV detection in PCR was positive, isolation of PRV failed after 5 blind passages in primary pig kidney cells and BHK21 cells. According to the animal pathogenicity, epidemiology and etiology analysis, this reproductive failure was most likely caused by dual infection of JEV and PRV. After immunization with Japanese encephalitis attenuated live vaccine (SA14-14-2 strain) and pseudorabies gene deletion vaccine (Bartha K61 strain), the reproductive problem was prevented and controlled successfully in pig herds.%云南省文山市某规模化猪场2015年7~8月频繁发生以种公猪一侧睾丸肿大,母猪流产、产死胎、木乃伊胎及弱仔为主要临床症状的繁殖障碍疫情.为了查明病因,对送检流产胎猪进行病理解剖,采集胎猪及胎盘病料进行猪瘟病毒、猪繁殖与呼吸综合征病毒欧洲型及美洲型毒株、猪细小病毒、伪狂犬病毒、乙型脑炎病毒、猪流产衣原体、布氏杆菌及弓形虫PCR和real-time PCR检测,同时应用猪肾原代细胞及BHK-21传代

  14. 山东省淄博市不同生境流行性乙型脑炎传播媒介蚊虫监测%Monitoring of mosquito vectors of Japanese encephalitis in different habitats of Zibo, Shandong

    Institute of Scientific and Technical Information of China (English)

    景晓; 刘桂芳; 王敏; 林小娟; 石志凯; 王广营; 司海霞

    2011-01-01

    目的 对淄博市的淄川区和高青县不同生境流行性乙型脑炎(乙脑)传播媒介蚊虫进行比较监测,调查当地突发乙脑病例的传播媒介蚊虫种类,为进一步防治乙脑提供依据.方法 用人帐法、网捕法、灯诱法、人工小时法,分别在稻田、畜禽舍、住宅区3种不同生境采集蚊虫,分类计数,以50只为单位放入液氮罐中带回实验室进行病毒分离;记录当地温度、湿度、风速等环境气候因素.结果 在3种生境中共捕获成蚊5属7种3116只,以稻田数量居多,占捕蚊总数的61.6%,畜禽舍次之,占24.1%,住宅区最少,占14.3%;三带喙库蚊、淡色库蚊是当地优势蚊种,分别占捕获总数的66.1%和19.1%.淄川区无稻田,淡色库蚊数量居多,占43.6%,三带喙库蚊次之,占34.0%.高青县以稻田为主,三带喙库蚊最多,占68.5%,淡色库蚊次之,占24.9%.入帐法捕获的蚊虫最多,占62.4%,灯诱法次之,占16.6%,人工小时法占14.6%,网捕法仅占6.4%.三带喙库蚊和淡色库蚊的叮刺高峰在日落后0.5~1 h达到活动高峰,持续约0~40 min,淡色库蚊的叮刺高峰迟20 min.结论 三带喙库蚊可能是当地乙脑的主要传播媒介,在进行野外蚊虫种类和数量监测时,应以人帐法和灯诱法为主,辅以网捕法和人工小时法.%Objective To survey the species, distribution, habitat, behavior of vectors of Japanese encephalitis in Zichuan district and Caoqing county of Zibo, Shandong. Methods The human baited net traps, mosquito nets, lamp baited traps and labor - hour methods were employed to investigate the mosquito counts of three habitats - rice field, domestic fowls shed, and household. The environmental factors were documented. Fifty mosquitoes from each group were preserved in liquid-nitrogen jars for viral isolation under laboratory settings. Results Of the 3116 mosquitoes collected, 7 species of 5 genera were found. Most mosquitoes were captured from

  15. Cavity Forming Pneumonia Due to Staphylococcus aureus Following Dengue Fever.

    Science.gov (United States)

    Miyata, Nobuyuki; Yoshimura, Yukihiro; Tachikawa, Natsuo; Amano, Yuichiro; Sakamoto, Yohei; Kosuge, Youko

    2015-11-01

    While visiting Malaysia, a 22-year-old previously healthy Japanese man developed myalgia, headache, and fever, leading to a diagnosis of classical dengue fever. After improvement and returning to Japan after a five day hospitalization, he developed productive cough several days after defervescing from dengue. Computed tomography (CT) thorax scan showed multiple lung cavities. A sputum smear revealed leukocytes with phagocytized gram-positive cocci in clusters, and grew an isolate Staphylococcus aureus sensitive to semi-synthetic penicillin; he was treated successfully with ceftriaxone and cephalexin. This second reported case of pneumonia due to S. aureus occurring after dengue fever, was associated both with nosocomial exposure and might have been associated with dengue-associated immunosuppression. Clinicians should pay systematic attention to bacterial pneumonia following dengue fever to establish whether such a connection is causally associated.

  16. Survey on natural infection of Japanese encephalitis virus in mosquitoes in Longgang District of Shenzhen City%深圳市龙岗区蚊虫自然感染流行性乙型脑炎病毒状况调查

    Institute of Scientific and Technical Information of China (English)

    邹志辉; 周健明; 林琳; 刘渠; 张起文; 王德全

    2012-01-01

    目的 研究深圳市龙岗区蚊虫流行性乙型脑炎病毒自然感染状况,为预测该地区乙脑发病趋势及流行强度,制定有效预防控制措施提供科学依据.方法 采用灯诱法捕捉蚊虫标本并进行分类鉴定,以JEV的NS3基因区段设计特异引物,通过实时荧光RT-PCR (real-time RT-PCR)对蚊虫中流行性乙型脑炎病毒进行检测,阳性标本经测序后再在GenBank中进行核苷酸序列的同源性比对.结果 捕获的蚊虫隶属3属5种,致倦库蚊是优势蚊种;1 533只蚊虫分成25批,从3批致倦库蚊标本中检出JEV核酸阳性,阳性率为12%.阳性标本与GenBank中报道的JEV参考株间相应的核苷酸序列同源性达99%以上,均属于JEV Ⅰ型病毒.结论 龙岗区存在着蚊虫自然感染JEV,致倦库蚊是区内乙脑传播的主要蚊媒,有流行人间和畜间流行性乙型脑炎的潜在危险,提示应进一步完善疫苗接种和免疫监测,积极开展消除蚊虫孳生地,灭蚊、防蚊工作,以控制和切断乙脑传播途径.%OBJECTIVE To explore JEV natural infection of captured mosquitoes in Longgang District of Shenzhen City and provide reference for prediction of the prevalence trend and intension of the epidemic encephalitis B. METHODS Lamp baited trap was used to capture mosquitoes. JEV specific primers in NS5 were designed and the Japanese encephalitis virus was identified with real-time RT-PCR. The nucleonic acid detection of positive samples was confirmed by sequencing and the NS3 gene sequence was compared with that published in GenBank. Then the genotype of Japanese encephalitis virus was determined. RESULTS Mosquitoes collected were subjected to 3 genera 5 species and Culex fatigans was dominant population. A total of 1 533 mosquitoes were collected and divided into 25 groups, and 12% were identified positive for viral RNA. The real-time RT-PCR assay showed that 3 positive samples were all Culex fatigans. Aligning the sequence with the Gen

  17. Differential Dengue Tropism & Neutralization: Potential Mechanisms of Pathogenesis

    Science.gov (United States)

    2006-01-04

    neutralization of two animal viruses , western equine encephalitis virus and poliomyelitis virus . Virology 2, 162-205. Endy, T.P., Nisalak, A., Chunsuttitwat...8035 was more efficient at utilizing both lectin receptors than American viruses overall; however Asian virus preferentially utilized L-SIGN at all...streptomycin (100µg/ml), L-glutamine, and nonessential amino acids at 28ºC/5% CO2. Virus seed production. The dengue viruses used in this study

  18. Dengue in India

    OpenAIRE

    Gupta, Nivedita; Srivastava, Sakshi; Jain, Amita; Chaturvedi, Umesh C.

    2012-01-01

    Dengue virus belongs to family Flaviviridae, having four serotypes that spread by the bite of infected Aedes mosquitoes. It causes a wide spectrum of illness from mild asymptomatic illness to severe fatal dengue haemorrhagic fever/dengue shock syndrome (DHF/DSS). Approximately 2.5 billion people live in dengue-risk regions with about 100 million new cases each year worldwide. The cumulative dengue diseases burden has attained an unprecedented proportion in recent times with sharp increase in ...

  19. Unusual acute encephalitis involving the thalamus: imaging features

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sam Soo [Kangwon National University Hospital, Chuncheon (Korea, Republic of); Chang, Kee Hyun; Kim, Kyung Won; Han Moon Hee [Seoul National University College of Medicine, Seoul (Korea, Republic of); Park, Sung Ho; Nam, Hyun Woo [Seoul City Boramae Hospital, Seoul (Korea, Republic of); Choi, Kyu Ho [Kangnam St. Mary' s Hospital, Seoul (Korea, Republic of); Cho, Woo Ho [Sanggyo Paik Hospital, Seoul (Korea, Republic of)

    2001-06-01

    To describe the brain CT and MR imaging findings of unusual acute encephalitis involving the thalamus. We retrospectively reviewed the medical records and CT and/or MR imaging findings of six patients with acute encephalitis involving the thalamus. CT (n=6) and MR imaging (n=6) were performed during the acute and/or convalescent stage of the illness. Brain CT showed brain swelling (n=2), low attenuation of both thalami (n=1) or normal findings (n=3). Initial MR imaging indicated that in all patients the thalamus was involved either bilaterally (n=5) or unilaterally (n=1). Lesions were also present in the midbrain (n=5), medial temporal lobe (n=4), pons (n=3), both hippocampi (n=3) the insular cortex (n=2), medulla (n=2), lateral temporal lobe cortex (n=1), both cingulate gyri (n=1), both basal ganglia (n=1), and the left hemispheric cortex (n=1). These CT or MR imaging findings of acute encephalitis of unknown etiology were similar to a combination of those of Japanese encephalitis and herpes simplex encephalitis. In order to document the specific causative agents which lead to the appearance of these imaging features, further investigation is required.

  20. 猪乙型脑炎病毒EⅢ与猪细小病毒VP2基因的串联表达及免疫原性%Coexpression for E Ⅲ gene of Japanese encephalitis virus and VP2 gene of porcine parvovirus and its immunogenicity

    Institute of Scientific and Technical Information of China (English)

    李云云; 郭万柱; 徐志文; 林华; 李宇; 漆信桥

    2011-01-01

    E Ⅲ gene of Japanese encephalitis virus and VP2 gene of porcine parvovirus were fused with linker by o-verlapping extension PCR and cloned into the eukaryotic expression vector pCI-neo. The obtained recombinant plas-mid pCI-VP2-EⅢ was transformed into Vero cell and the expression product was identified by RT-PCR and indirect immunofluorscence assay. Mice were immunized with recombinant plasmid,in the absence of adjuvant, empty plas-mid vaccinated group,inactivated vaccine against porcine parvovirus and swine attenuated Japanese encephalitis immunization group and phosphate buffered saline inoculated group were as the control reference. The result showed that recombinant plasmid of pCI-VP2-EⅢ could induce immunize reponse at lw post-boosting immunization and the antibody levels reached a peak at post-three immunization; spleen lymphocyte proliferative response showed that recombinant bacteria on Con A reactivity significantly, and the significan