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Badole S.L.,National Institute of Virology ICMR | Yadav P.D.,National Institute of Virology ICMR | Patil D.R.,National Institute of Virology ICMR | Mourya D.T.,National Institute of Virology ICMR
Journal of Vector Borne Diseases | Year: 2015

Viral hemorrhagic fevers (VHFs) are major public health problems in the South-East Asia Regional (SEAR) countries. VHFs are a group of illnesses; that are caused by four families of viruses, viz. Arenaviridae, Bunyaviridae, Filoviridae and Flaviviridae. All VHFs have common features: they affect several organs and damage the blood vessels. These symptoms are often accompanied by hemorrhage. To understand pathogenesis, genetic and environmental influence that increase the risk of VHFs, efficacy and safety studies on candidate vaccines and testing of various therapeutic agents, appropriate animal models are essential tools in public and animals health. In the current review, the suitable animal models for Flavivirus [Dengue hemorhagic fever (DHF), Kyasanur forest disease (KFD)]; Bunyavirus [Crimean-Congo hemorrhagic fever (CCHF), Hantavirus fever (HF)]; and Paramyxovirus [Nipah virus fever (NiV)] have been reviewed with specific emphasis on emerging and reemerging viruses in SEAR countries. © 2015,Journal of Vector Borne Diseases. All rights reserved.


Gangodkar S.,National Institute of Virology ICMR | Jain P.,National Institute of Virology ICMR | Dixit N.,National Institute of Virology ICMR | Ghosh K.,13th Floor KEM Hospital | Basu A.,National Institute of Virology ICMR
Journal of Electron Microscopy | Year: 2010

The biogenesis events and formation of dengue virus (DENV) in the infected host cells remain incompletely understood. In the present study, we examined the ultrastructural changes associated with DENV-2 replication in three susceptible host cells, C6/36, Vero and SK Hep1, a cell line of human endothelial origin, using transmission electron microscopy, whole-mount grid-cell culture techniques and electron tomography (ET). The prominent feature in C6/36 cells was the formation of large perinuclear vacuoles with mature DENV particles, and on-grid whole-mount examination of the infected Vero cells showed different forms of DENV core structures associated with cellular membranes within 48 h after infection. Distinct multivesicular structures and prominent autophagic vesicles were seen in the infected SK Hep1 cells when compared with the other two cell lines. ET showed the three-dimensional organization of these vesicles as a continuous system. This is the first report of ET-based analysis of DENV-2 replication in a human endothelial cell line. These results further emphasizes the strong role played by intracellular host membranesvirus interactions in the biogenesis of DENV and strongly argues for the possibility of targeting compounds to block such structure formation as key anti-dengue agents. © The Author 2010. Published by Oxford University Press on behalf of Japanese Society of Microscopy. All rights reserved.


Verma H.,National Institute of Virology ICMR | Chitambar S.D.,National Institute of Virology ICMR | Gopalkrishna V.,National Institute of Virology ICMR
Infection, Genetics and Evolution | Year: 2010

A five-year (2004-2008) study was conducted on patients with acute gastroenteritis from different cities of Maharashtra, western India to detect and characterize astrovirus infections. A total of 1340 fecal specimens were collected from sporadic cases that included 1240 children (≤8 years) and 100 adults (18-70 years) from Pune, Aurangabad and Nagpur cities. All specimens were subjected to astrovirus specific RT-PCR followed by sequencing and phylogenetic analysis. The overall positivity to astrovirus was found to be 3.1% with highest number of infections in winter months. A high prevalence of astrovirus was observed in children ≤1 year of age. Phylogenetic analysis of the partial ORF1a (serine protease) and ORF2 (capsid gene) regions showed the circulation of three probable recombinant types with different ORF1a/ORF2 specificities (HAstV-8/HAstV-1, HAstV-7/HAstV-2, HAstV-4/HAstV-5) along with HAstV-8 of a single specificity in the study population. HAstV-8/HAstV-1, specificity predominated (67.7%) in the region followed by HAstV-7/HAstV-2 (9.7%), HAstV-4/HAstV-5 (6.5%) and HAstV-8 (16%) types. This is the first report that highlights the genetic diversity of astrovirus strains circulating in Maharashtra state, western India. © 2010 Elsevier B.V.


Alagarasu K.,National Institute of Virology ICMR | Bachal R.V.,National Institute of Virology ICMR | Memane R.S.,National Institute of Virology ICMR | Shah P.S.,National Institute of Virology ICMR | Cecilia D.,National Institute of Virology ICMR
Immunobiology | Year: 2015

Functional polymorphisms in RNA recognizing toll like receptors (TLR) 3, 7, 8 and toll-interleukin-1 receptor domain containing adapter protein adapter (TIRAP) coding genes were investigated in 120 dengue cases [87 dengue fever (DF) cases and 33 dengue hemorrhagic fever (DHF) cases] and 109 healthy controls (HC) to identify their association with clinical outcomes of dengue virus infection. Results revealed significantly lower frequency of TLR3 rs3775291 T allele [DHF vs. DF P=. 0.015 odds ratio (OR) with 95% confidence interval (CI) 0.390 (0.160-0.880); DHF vs. HC P=. 0.018 OR with 95% CI 0.410 (0.170-0.900)] and 'T' allele carriers [DHF vs. DF P=. 0.008 OR with 95% CI 0.288 (0.115-0.722); DHF vs. HC P=. 0.040 OR with 95% CI 0.393 (0.162-0.956)] and higher frequency of TIRAP rs8177374 'C/T' genotype [DHF vs. HC P=. 0.020 OR with 95% CI 2.643 (1.167-5.986)] in DHF. Higher frequency of TLR8 rs3764879-rs3764880 haplotype C-A was observed in male DF cases compared to male HC [. P=. 0.025 OR with 95% CI 2.185 (1.101-4.336)]. The results suggest that TLR3 and TIRAP gene variants influence the risk for DHF. © 2014 Elsevier GmbH.


Apte-Deshpande A.D.,University of Pune | Paingankar M.S.,University of Pune | Gokhale M.D.,National Institute of Virology ICMR | Deobagkar D.N.,University of Pune
Indian Journal of Medical Research | Year: 2014

Background & objectives: The susceptibility of the mosquito to the invading pathogen is predominantly dictated by the complex interactions between the mosquito midgut and the surface proteins of the invading pathogen. It is well documented that the midgut microbiota plays an important role in determining the susceptibility of the mosquito to the pathogen. In the present study, we investigated the influence of Serratia odorifera, an endogenous cultivable midgut inhabitant of Aedes aegypti on the chikungunya virus (CHIKV) susceptibility to this mosquito. Methods: Ae. aegypti females free of gutflora were co-fed with CHIKV and either of the two midgut inhabitants namely, S. odorifeara and Microbacterium oxydans. CHIKV dissemination was checked on 10th day post feeding (DPF) using indirect immunoflurescence assay and plaque assay. CHIKV interacting proteins of the mosquito midgut were identified using virus overlay protein binding assay and MALDI TOF/TOF analysis. Results: The observations revealed that co-feeding of S. odorifera with CHIKV significantly enhanced the CHIKV susceptibility in adult Ae. aegypti, as compared to the mosquitoes fed with CHIKV alone and CHIKV co-fed with another midgut inhabitant, M. oxydans. Virus overlay protein binding assay (VOPBA) results revealed that porin and heat shock protein (HSP60) of Ae. aegypti midgut brush border membrane fraction interacted with CHIKV. Interpretation & conclusions: the results of this study indicated that the enhancement in the CHIKV susceptibility of Ae. aegypti females was due to the suppression of immune response of Ae. aegypti as a result of the interaction between S. odorifera P40 protein and porin on the gut membrane.


Yadav P.D.,National Institute of Virology ICMR | Sudeep A.B.,National Institute of Virology ICMR | Mishra A.C.,National Institute of Virology ICMR | Mourya D.T.,National Institute of Virology ICMR
Indian Journal of Medical Research | Year: 2012

Background & objectives: Chittoor virus (CHITV) belongs to genus Orthobunyavirus, family Bunyaviridae. It has been isolated from various species of mosquitoes and pig from different parts of India. Five isolates of CHITV were characterized at the molecular level and compared with other Batai viruses (BATV) to find out any kind of reassortment in their genome. Methods: Complete nucelocapsid (S), glycoprotein (M) and partial RNA polymerase (L) segments of CHITV were amplified and sequenced. These sequences were compared with those of Batai viruses, isolated from different geographical locations in Asia, Africa and Europe. Results: Phylogenetic analysis revealed CHITV as a variant of BATV. High level of conservation was seen among the CHITV isolates studied. The CHITV sequences showed clustering in one lineage with the sequences from Japan and Malaysia, however, BATV sequences from Europe and Africa formed a separate phylogenetic lineage. Interpretation & conclusions: The study indicates the presence of a single genotype of CHITV circulating in India, despite the involvement of different hosts in the natural cycle by this virus. Analysis of the sequences of the S, M and L segments of genome indicated that the virus has not undergone any reassortment. This virus has not caused any epidemic involving humans, however, replication of the virus in different mosquito and vertebrate hosts species suggests that it is a cause of concern.


Jadi R.S.,National Institute of Virology ICMR | Sudeep A.B.,National Institute of Virology ICMR | Kumar S.,National Institute of Virology ICMR | Arankalle V.A.,National Institute of Virology ICMR | Mishra A.C.,National Institute of Virology ICMR
Indian Journal of Medical Research | Year: 2010

Background & objectives: Since not much information on Chandipura virus is available, an attempt was made to study the growth kinetics of the virus in certain vertebrate, invertebrate cell lines and embryonated chicken eggs. Methods: Comparative study of Chandipura virus (CHPV) growth kinetics in three vertebrate cell lines [Vero E6, Rhabdo myosarcoma (RD), Porcine stable kidney (PS) cell lines], two insect cell lines [Aedes aegypti (AA) and Phlebotomus papatasi (PP-9) cell lines] and embryonated pathogen free chicken eggs was conducted, by tissue culture infective dose 50 per cent (TCID50) and indirect immunofuorescence assay (IFA). Results: All the cell lines and embryonated egg supported the growth of CHPV and yielded high virus titre. The vertebrate cell lines showed distinct cytopathic effect (CPE) within 4-6 h post infection (PI), while no CPE was observed in insect cell lines. PP-9 cell line was the most sensitive system to CHPV as viral antigen could be detected at 1 h PI by IFA. Interpretation & conclusions: Our results demonstrated that all the systems were susceptible to CHPV and achieved high yield of virus. However, the PP-9 cell line had an edge over the others due to its high sensitivity to the virus which might be useful for detection and isolation of the virus during epidemics.


Sudeep A.B.,National Institute of Virology ICMR | Gurav Y.K.,National Institute of Virology ICMR | Bondre V.P.,National Institute of Virology ICMR
Indian Journal of Medical Research | Year: 2016

Chandipura virus (CHPV) (Vesiculovirus: Rhabdoviridae) garnered global attention as an emerging neurotropic pathogen inflicting high mortality in children within 24 h of commencement of symptoms. The 2003-2004 outbreaks in Central India witnessed case fatality rates ranging from 56-75 per cent in Andhra Pradesh and Gujarat with typical encephalitic symptoms. Due to the acute sickness and rapid deterioration, the precise mechanism of action of the virus is still unknown. Recent studies have shown increased expression of CHPV phosphoprotein upto 6 h post infection (PI) demonstrating CHPV replication in neuronal cells and the rapid destruction of the cells by apoptosis shed light on the probable mechanism of rapid death in children. Phlebotomine sandflies are implicated as vectors due to their predominance in endemic areas, repeated virus isolations and their ability to transmit the virus by transovarial and venereal routes. Significant contributions have been made in the development of diagnostics and prophylactics, vaccines and antivirals. Two candidate vaccines, viz. a recombinant vaccine and a killed vaccine and siRNAs targeting P and M proteins have been developed and are awaiting clinical trials. Rhabdomyosarcoma and Phlebotomus papatasi cell lines as well as embryonated chicken eggs have been found useful in virus isolation and propagation. Despite these advancements, CHPV has been a major concern in Central India and warrants immediate attention from virologists, neurologists, paediatricians and the government for containing the virus. © 2016, Indian Council of Medical Research. All rights Reserved.


Vaidya S.R.,National Institute of Virology ICMR | Dvivedi G.M.,National Institute of Virology ICMR | Jadhav S.M.,National Institute of Virology ICMR
Indian Journal of Medical Research | Year: 2016

Background & objectives: The reports from the countries where mumps vaccine is given as routine immunization suggest differences in mumps virus neutralizing antibody titres when tested with vaccine and wild type viruses. Such reports are unavailable from countries like India where mumps vaccine is not included in routine immunization. We, therefore, undertook this study to understand the cross-neutralization activity of Indian mumps viruses. Methods: By using commercial mumps IgG enzyme immunoassay (EIA) and a rapid focus reduction neutralization test (FRNT), a panel of serum samples was tested. The panel consisted of 14 acute and 14 convalescent serum samples collected during a mumps outbreak and 18 archived serum samples. Two wild types (genotypes C and G) and Leningrad-Zagreb vaccine strain (genotype N) were used for the challenge experiments and FRNT titres were determined and further compared. The HN protein sequence of three mumps viruses was analyzed for the presence of key epitopes. Results: All serum samples effectively neutralized mumps virus wild types and a vaccine strain. However, significantly lower FRNT titres were noted to wild types than to vaccine strain (P<0.05). The comparison between EIA and FRNT results revealed 95.6 per cent agreement. No amino acid changes were seen in the epitopes in the Indian wild type strains. All potential N-linked glycosylation sites were observed in Indian strains. Interpretation & conclusions: Good cross-neutralization activity was observed for three mumps virus strains, however, higher level of FRNT titres was detected for mumps virus vaccine strain compared to Indian wild type isolates. © 2016, Indian Council of Medical Research. All rights reserved.


Sahu H.K.,Inter-University Center for Astronomy and Astrophysics | Singh S.N.,National Institute of Virology ICMR
Aslib Proceedings: New Information Perspectives | Year: 2013

Purpose: The purpose of this study is to examine different aspects of information seeking behaviour, and specifically the information seeking behaviour and information needs of Indian astronomy/astrophysics academics, including the relationship between various variables such as academic, rank-wise statuses, age-wise of characteristics, and methods for keeping their knowledge up-to-date. Design/methodology/approach: A stratified random sample survey was used for gathering data. However, to support and authenticate the data quantitative and qualitative approaches were used. The questionnaire was mailed and was also available online. Some 400 academics from 12 astronomy and astrophysics information centres and libraries were surveyed using the questionnaire and were interviewed. The questionnaire response rate was 72 percent (288/400). Findings: The study findings show: differences in information seeking behaviour and needs for various academic is sub-fields of Indian astronomy/astrophysics, and highlights the value of information seeking behaviour to scientists working in astronomy/astrophysics. The study concludes that astronomy/astrophysics academics were making use of Astrophysics Data System followed by their use of e-archives for education and research. Astronomy/astrophysics academics work in a unique setting with specialized needs. The study findings underscored the need to continue accessing specialized needs to find innovative solutions. There are challenges and opportunities for exciting new initiatives. Originality/value: This is the first in-depth study in India exploring the information seeking behaviour and information needs of astronomy/astrophysics academics. It also gives the latest account of information seeking behaviour of information users in astronomy/astrophysics discipline. The study is also expected to guide other information service organisations to cope with their users' needs, by adopting survey methods, tools, protocols used in this study. © Emerald Group Publishing Limited.

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