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1.
Infect Genet Evol ; 93: 104909, 2021 09.
Article in English | MEDLINE | ID: mdl-34082088

ABSTRACT

Dengue is the most common mosquito-borne viral infection in tropical and sub-tropical countries. In the recent years, frequent dengue outbreaks are being reported in many parts of India. DENV circulates as four independent serotypes posing a major public health threat around the globe. Phylogenetic and full genome sequence analyses of 19 complete DENV genome sequences presenting all the four serotypes in Pune, India (2016-2017) revealed no change in the circulating genotypes i.e., genotype V clade C (D1), genotype IVB (D2), genotype III lineage III (D3) and genotype I clade D (D4). Additionally, unique amino acid substitutions that may potentially influence viral fitness and virulence in host cells were identified. Mapping of the unique amino acid substitutions onto the T cell epitopes of the reference strains revealed that 8/10 (D1), 14/15 (D2), 3/4 (D3) and 21/74 (D4), amino acids were involved in T-cell epitope presentation for a maximum number of HLA alleles associated with disease outcome. Selection pressure analysis documented a positive selection pressure to be acting on few amino acid sites indicating continuous evolutionary changes in the viral RNA. Overall, the evolutionary and selection pressure data generated during this study may help in better understanding of DENV evolution and epidemiology.


Subject(s)
Dengue Virus/genetics , Evolution, Molecular , Genome, Viral , Genotype , Amino Acid Substitution , India , Phylogeny , Serogroup , Whole Genome Sequencing
2.
Acta Virol ; 62(2): 208-213, 2018.
Article in English | MEDLINE | ID: mdl-29895163

ABSTRACT

The etiological agent remained unidentified in a large number of patients hospitalized for acute encephalitis syndrome (AES) in 2008-2009 in Uttar Pradesh and Bihar, north India. All patients were found to present with fever and altered sensorium, while 28%, 19% and 13% showed hepatomegaly, splenomegaly and meningeal signs, respectively. Involvement mostly of children with abnormal hepatic features prompted us to undertake an exploratory study on viral hepatitis A to determine its association, if any, with hepatic derangements. AES patients (n = 2515) and healthy children (n = 167) were investigated for the presence of serum anti-hepatitis A virus (anti-HAV) IgM and anti-Japanese encephalitis (anti-JE) virus IgM by ELISA. Cerebrospinal fluids (CSFs, n = 595) and rectal swabs (n = 182) were examined for anti-HAV IgM and/or HAV RNA. Anti-HAV IgM was detected in the sera of 14.6% patients as against 6.6% of healthy children (p = 0.0042). Anti-JE virus IgM positivity was Keywords: acute encephalitis syndrome; cerebrospinal fluid; hepatitis A virus; anti-HAV IgM; non-Japanese encephalitis.


Subject(s)
Acute Febrile Encephalopathy/virology , Hepatitis A virus/physiology , Hepatitis A/virology , Acute Febrile Encephalopathy/blood , Acute Febrile Encephalopathy/diagnosis , Acute Febrile Encephalopathy/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Viral/blood , Child , Child, Preschool , Enzyme-Linked Immunosorbent Assay , Female , Hepatitis A/blood , Hepatitis A/diagnosis , Hepatitis A/epidemiology , Hepatitis A virus/genetics , Humans , India/epidemiology , Infant , Male , Middle Aged , Young Adult
3.
Indian J Med Res ; 140(2): 244-51, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25297358

ABSTRACT

BACKGROUND & OBJECTIVES: Recent influenza antiviral resistance studies in South East Asia, Europe and the United States reveal adamantane and neuraminidase inhibitor (NAIs) resistance. This study was undertaken to evaluate antiviral resistance in influenza viruses isolated from various parts of India, during 2004 to 2011. METHODS: Influenza viruses were analyzed genetically for known resistance markers by M2 and NA gene sequencing. Influenza A/H1N1 (n=206), A/H3N2 (n=371) viruses for amantadine resistance and A/H1N1 (n=206), A/H3N2 (n=272) and type B (n=326) for oseltamivir resistance were sequenced. Pandemic (H1N1) (n=493) isolates were tested for H274Y mutation by real time reverse transcription (rRT)-PCR. Randomly selected resistant and sensitive influenza A/H1N1 and A/H3N2 viruses were confirmed by phenotypic assay. RESULTS: Serine to asparagine (S3IN) mutation was detected in six isolates of 2007-2008. One dual-resistant A/H1N1 was detected for the first time in India with leucine to phenylalanine (L26F) mutation in M2 gene and H274Y mutation in NA gene. A/H3N2 viruses showed an increase in resistance to amantadine from 22.5 per cent in 2005 to 100 per cent in 2008 onwards with S3IN mutation. Fifty of the 61 (82%) A/H1N1 viruses tested in 2008-2009 were oseltamivir resistant with H274Y mutation, while all A/H3N2, pandemic A/H1N1 and type B isolates remained sensitive. Genetic results were also confirmed by phenotypic analysis of randomly selected 50 resistant A/H1N1 and 40 sensitive A/H3N2 isolates. INTERPRETATION & CONCLUSIONS: Emergence of influenza viruses resistant to amantadine and oseltamivir in spite of negligible usage of antivirals emphasizes the need for continuous monitoring of antiviral resistance.


Subject(s)
Drug Resistance, Viral/genetics , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H3N2 Subtype/genetics , Influenza B virus/genetics , Amantadine , Base Sequence , Cluster Analysis , Genetic Markers/genetics , Humans , India , Models, Genetic , Molecular Sequence Data , Mutation, Missense , Oseltamivir , Phylogeny , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA
4.
Indian J Med Res ; 139(5): 769-72, 2014 May.
Article in English | MEDLINE | ID: mdl-25027088

ABSTRACT

BACKGROUND & OBJECTIVES: An outbreak of acute encephalitis syndrome was reported from Vidarbha region of Maharashtra s0 tate, India, during July 2012. Anti-IgM antibodies against Chandipura virus (CHPV) were detected in clinical samples. Sandfly collections were done to determine their role in CHPV transmission. METHODS: Twenty nine pools of Sergentomyia spp. comprising 625 specimens were processed for virus isolation in Vero E6 cell line. Diagnostic RT-PCR targeting N-gene was carried out with the sample that showed cytopathic effects (CPE). The PCR product was sequenced, analysed and the sequences were deposited in Genbank database. RESULTS: CPE in Vero E6 cell line infected with three pools was detected at 48 h post infection. However, virus could be isolated only from one pool. RT-PCR studies demonstrated 527 nucleotide product that confirmed the agent as CHPV. Sequence analysis of the new isolate showed difference in 10-12 nucleotides in comparison to earlier isolates. INTERPRETATION & CONCLUSIONS: This is perhaps the first isolation of CHPV from Sergentomyia spp. in India and virus isolation during transmission season suggests their probable role in CHPV transmission. Further studies need to be done to confirm the precise role of Sargentomyia spp. in CHPV transmission.


Subject(s)
Phlebotomus/pathogenicity , Psychodidae/virology , Rhabdoviridae Infections/transmission , Vesiculovirus/isolation & purification , Animals , Antibodies, Anti-Idiotypic/isolation & purification , Chlorocebus aethiops , Encephalitis/epidemiology , Encephalitis/virology , India , Phlebotomus/virology , Psychodidae/pathogenicity , Rhabdoviridae Infections/epidemiology , Rhabdoviridae Infections/virology , Vero Cells , Vesiculovirus/pathogenicity
5.
Indian J Med Res ; 139(3): 418-26, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24820836

ABSTRACT

BACKGROUND & OBJECTIVES: During the post influenza pandemic period, continuous surveillance of influenza virus and its subtypes is mandatory to help the policy makers to take effective and appropriate decisions. Therefore, this study was planned to determine the pattern of influenza virus activity in context to various meteorological and clinical parameters in and around Lucknow, Uttar Pradesh, India, during post pandemic period August 2010 - September 2012. METHODS: Nasal swabs/throat swabs/nasopharyngeal aspirates of 2669 patients were collected. One-step real time PCR for detection of influenza virus was done according to the Centers for Disease Control and Prevention (CDC) protocol. RESULTS: Influenza positivity was 15.8 per cent (423/2669) in symptomatic patients. Of the 423 total positives, 192 (7.2%) were influenza A and 231 (8.7%) were influenza B. Positivity for influenza virus was significantly (P=0.001, OR=2.9, CI=1.9-4.3) higher in patients with Influenza like illness (ILI) (17.4%, 396/2271) than those with severe acute respiratory illness (SARI) (6.8%, 27/398). Influenza A positive samples were subtyped as; pdmH1N1 (67.2%, 129/192) and seasonal H3N2 (32.8%, 63/192). It significantly correlated with monthly mean rainfall, humidity and dew point while atmospheric pressure was inversely related. No significant association was found with temperature and wind speed. Clinical variations were observed between different strains of Influenza virus. INTERPRETATION & CONCLUSIONS: The findings provide a clear picture of different clinical presentations of various strains of influenza A and B viruses and epidemiology of influenza infection from Lucknow (UP), India. The seasonality of influenza virus infection showed variation in relation to different environmental factors. Pandemic H1N1 caused more systemic infection than seasonal influenza A/H3N2 virus.


Subject(s)
Influenza, Human/epidemiology , Influenza, Human/virology , Orthomyxoviridae/genetics , Pandemics/history , Epidemiological Monitoring , Genotype , History, 21st Century , Humans , India/epidemiology , Odds Ratio , Orthomyxoviridae/classification , Real-Time Polymerase Chain Reaction
6.
Indian J Med Microbiol ; 32(1): 13-8, 2014.
Article in English | MEDLINE | ID: mdl-24399381

ABSTRACT

CONTEXT: Acute lower respiratory tract infections (ALRI), ranked as the second leading cause of death are the primary cause of hospitalisation in children. Viruses are the most important causative agents of ALRI. AIM: To study the viral aetiology of ALRI in children at a tertiary care hospital. SETTING AND DESIGN: One year prospective observational study in a tertiary care hospital of King George's Medical University, Lucknow. MATERIAL AND METHODS: Nasopharyngeal aspirate (NPA) was collected from children admitted with signs and symptoms of ALRI who were aged 0-14 years. Samples were transported to the laboratory at 4°C in viral transport media and processed for detection of respiratory syncytial virus (RSV) A and B, influenza virus A and B, adenovirus (ADV), human Boca virus (HBoV), human metapneumo virus (hMPV) and parainfluenzavirus 1, 2, 3 and 4 using mono/multiplex real-time polymerase chain reaction (RT-PCR). STATA was used for statistical analysis. RESULTS: In one year, 188 NPAs were screened for respiratory viruses, of which 45.7% tested positive. RSV was most commonly detected with 21.3% positivity followed by measles virus (8.5%), influenza A virus (7.4%), ADV (5.3%), influenza B virus (1.6%), hMPV (1.1%) and HBoV (0.5%). Month wise maximum positivity was seen in December and January. Positivity rate of RSV was highest in children aged < 1 year, which decreased with increase in age, while positive rate of influenza virus increased with increasing age. CONCLUSION: The occurrence of viral predominance in ALRI is highlighted.


Subject(s)
Pneumonia, Viral/epidemiology , Pneumonia, Viral/etiology , Viruses/classification , Viruses/isolation & purification , Adolescent , Bodily Secretions/virology , Child , Child, Preschool , Humans , India/epidemiology , Infant , Infant, Newborn , Male , Molecular Diagnostic Techniques , Nasopharynx/virology , Polymerase Chain Reaction , Prospective Studies , Tertiary Care Centers
8.
Intervirology ; 55(6): 488-90, 2012.
Article in English | MEDLINE | ID: mdl-22572722

ABSTRACT

Surveillance work was initiated to study the presence of highly infectious diseases like Ebola-Reston, Marburg, Nipah and other possible viruses that are known to be found in the bat species and responsible for causing diseases in humans. A novel adenovirus was isolated from a common species of fruit bat (Rousettus leschenaultii) captured in Maharashtra State, India. Partial sequence analysis of the DNA polymerase gene shows this isolate to be a newly recognized member of the genus Mastadenovirus (family Adenoviridae), approximately 20% divergent at the nucleotide level from Japanese BatAdV, its closest known relative.


Subject(s)
Adenoviridae Infections/veterinary , Chiroptera/virology , Mastadenovirus/isolation & purification , Adenoviridae Infections/diagnosis , Adenoviridae Infections/virology , Animals , DNA-Directed DNA Polymerase/analysis , DNA-Directed DNA Polymerase/genetics , India , Mastadenovirus/classification , Mastadenovirus/genetics , RNA, Viral/genetics
9.
Indian J Med Res ; 136(5): 792-8, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23287126

ABSTRACT

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.


Subject(s)
Bunyamwera virus/genetics , Animals , Base Sequence , Bunyamwera virus/classification , Bunyamwera virus/isolation & purification , Chlorocebus aethiops , DNA Primers , India , Phylogeny , Vero Cells
11.
Influenza Other Respir Viruses ; 6(2): 142-52, e1-5, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21819547

ABSTRACT

• For almost 60 years, the WHO Global Influenza Surveillance and Response System (GISRS) has been the key player in monitoring the evolution and spread of influenza viruses and recommending the strains to be used in human influenza vaccines. The GISRS has also worked to continually monitor and assess the risk posed by potential pandemic viruses and to guide appropriate public health responses. • The expanded and enhanced role of the GISRS following the adoption of the International Health Regulations (2005), recognition of the continuing threat posed by avian H5N1 and the aftermath of the 2009 H1N1 pandemic provide an opportune time to critically review the process by which influenza vaccine viruses are selected. In addition to identifying potential areas for improvement, such a review will also help to promote greater appreciation by the wider influenza and policy-making community of the complexity of influenza vaccine virus selection. • The selection process is highly coordinated and involves continual year-round integration of virological data and epidemiological information by National Influenza Centres (NICs), thorough antigenic and genetic characterization of viruses by WHO Collaborating Centres (WHOCCs) as part of selecting suitable candidate vaccine viruses, and the preparation of suitable reassortants and corresponding reagents for vaccine standardization by WHO Essential Regulatory Laboratories (ERLs). • Ensuring the optimal effectiveness of vaccines has been assisted in recent years by advances in molecular diagnosis and the availability of more extensive genetic sequence data. However, there remain a number of challenging constraints including variations in the assays used, the possibility of complications resulting from non-antigenic changes, the limited availability of suitable vaccine viruses and the requirement for recommendations to be made up to a year in advance of the peak of influenza season because of production constraints. • Effective collaboration and coordination between human and animal influenza networks is increasingly recognized as an essential requirement for the improved integration of data on animal and human viruses, the identification of unusual influenza A viruses infecting human, the evaluation of pandemic risk and the selection of candidate viruses for pandemic vaccines. • Training workshops, assessments and donations have led to significant increases in trained laboratory personnel and equipment with resulting expansion in both geographical surveillance coverage and in the capacities of NICs and other laboratories. This has resulted in a significant increase in the volume of information reported to WHO on the spread, intensity and impact of influenza. In addition, initiatives such as the WHO Shipment Fund Project have facilitated the timely sharing of clinical specimens and virus isolates and contributed to a more comprehensive understanding of the global distribution and temporal circulation of different viruses. It will be important to sustain and build upon the gains made in these and other areas. • Although the haemagglutination inhibition (HAI) assay is likely to remain the assay of choice for the antigenic characterization of viruses in the foreseeable future, alternative assays - for example based upon advanced recombinant DNA and protein technologies - may be more adaptable to automation. Other technologies such as microtitre neuraminidase inhibition assays may also have significant implications for both vaccine virus selection and vaccine development. • Microneutralization assays provide an important adjunct to the HAI assay in virus antigenic characterization. Improvements in the use and potential automation of such assays should facilitate large-scale serological studies, while other advanced techniques such as epitope mapping should allow for a more accurate assessment of the quality of a protective immune response and aid the development of additional criteria for measuring immunity. • Standardized seroepidemiological surveys to assess the impact of influenza in a population could help to establish well-characterized banks of age-stratified representative sera as a national, regional and global resource, while providing direct evidence of the specific benefits of vaccination. • Advances in high-throughput genetic sequencing coupled with advanced bioinformatics tools, together with more X-ray crystallographic data, should accelerate understanding of the genetic and phenotypic changes that underlie virus evolution and more specifically help to predict the influence of amino acid changes on virus antigenicity. • Complex mathematical modelling techniques are increasingly being used to gain insights into the evolution and epidemiology of influenza viruses. However, their value in predicting the timing and nature of future antigenic and genetic changes is likely to be limited at present. The application of simpler non-mechanistic statistical algorithms, such as those already used as the basis of antigenic cartography, and phylogenetic modelling are more likely to be useful in facilitating vaccine virus selection and in aiding assessment of the pandemic potential of avian and other animal influenza viruses. • The adoption of alternative vaccine technologies - such as live-attenuated, quadrivalent or non-HA-based vaccines - has significant implications for vaccine virus selection, as well as for vaccine regulatory and manufacturing processes. Recent collaboration between the GISRS and vaccine manufacturers has resulted in the increased availability of egg isolates and high-growth reassortants for vaccine production, the development of qualified cell cultures and the investigation of alternative methods of vaccine potency testing. WHO will continue to support these and other efforts to increase the reliability and timeliness of the global influenza vaccine supply. • The WHO GISRS and its partners are continually working to identify improvements, harness new technologies and strengthen and sustain collaboration. WHO will continue in its central role of coordinating worldwide expertise to meet the increasing public health need for influenza vaccines and will support efforts to improve the vaccine virus selection process, including through the convening of periodic international consultations.


Subject(s)
Influenza Vaccines/immunology , Influenza, Human/epidemiology , Influenza, Human/prevention & control , Orthomyxoviridae/immunology , Orthomyxoviridae/isolation & purification , Vaccination/methods , Global Health , Humans , Influenza, Human/virology , Switzerland , World Health Organization
12.
J Assoc Physicians India ; 59: 498-500, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21887906

ABSTRACT

India reported its first case of H1N1 in July 2009 in Pune and since then, the number of reported cases and deaths exploded in India. Since very little data is available about histopathological findings in patients of H1N1 fatal cases in India, a retrospective chart analysis of necropsy findings of 15 cases of 2009 H1N1 fatal cases was performed. Common clinical features were fever, cough, and breathlessness followed by sore throat and rhinorrhea. Common lung findings were mononuclear cell infiltration, thick alveolar septae, intraalveolar hemorrhage. The other findings were congested pulmonary blood vessels, pulmonary edema, cytomegaly, fibrin accumulation and formation of eosinophilic membrane. These findings are suggestive of diffuse alveolar damage (DAD) and DAD with hemorrhage. All patients who underwent necropsy had radiographic findings suggestive of unilobar or multilobar pneumonia. This clinical finding can be correlated pathologically in these patients as all of them had either polymorphonuclear or mononuclear infiltrate. Furthermore, necrotizing pneumonitis pattern seen on these patients is the likely cause of mortality in these patients. Although clinical ARDS pattern was noted in all these patients, it was well correlated in lung pathology in all these cases.


Subject(s)
Influenza A Virus, H1N1 Subtype/isolation & purification , Influenza, Human/pathology , Liver/pathology , Lung/pathology , Adolescent , Adult , Autopsy , Comorbidity , Female , Hospitals, Teaching , Humans , India , Infant, Newborn , Influenza, Human/mortality , Influenza, Human/virology , Male , Middle Aged , Retrospective Studies , Young Adult
13.
J Infect Dis ; 204 Suppl 1: S403-13, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21666192

ABSTRACT

Measles is a childhood disease that causes great morbidity and mortality in India and worldwide. Because measles surveillance in India is in its infancy, there is a paucity of countrywide data on circulating Measles virus genotypes. This study was conducted in 21 of 28 States and 2 of 7 Union Territories of India by MeaslesNetIndia, a national network of 27 centers and sentinel practitioners. MeaslesNetIndia investigated 52 measles outbreaks in geographically representative areas from 2005 through June 2010. All outbreaks were serologically confirmed by detection of antimeasles virus immunoglobulin M (IgM) antibodies in serum or oral fluid samples. Molecular studies, using World Health Organization (WHO)-recommended protocols obtained 203 N-gene, 40 H-gene, and 4 M-gene sequences during this period. Measles genotypes D4, D7, and D8 were found to be circulating in various parts of India during the study period. Further phylogenetic analysis revealed 4 lineages of Indian D8 genotypes: D8a, D8b, D8c, and D8d. This study generated a large, countrywide sequence database that can form the baseline for future molecular studies on measles virus transmission pathways in India. This study has created support and capabilities for countrywide measles molecular surveillance that must be carried forward.


Subject(s)
Measles virus/genetics , Measles/epidemiology , Measles/virology , Adolescent , Adult , Age Distribution , Antibodies, Viral/blood , Child , Child, Preschool , Disease Outbreaks/statistics & numerical data , Genotype , Humans , Immunoglobulin M/blood , India/epidemiology , Infant , Measles virus/classification , Measles virus/immunology , Molecular Epidemiology , Phylogeny , Serologic Tests , Young Adult
14.
Vaccine ; 29(28): 4613-7, 2011 Jun 20.
Article in English | MEDLINE | ID: mdl-21549791

ABSTRACT

A Vero cell based vaccine candidate against Chandipura (CHP) virus (Rhabdoviridae: Vesiculovirus), was developed and evaluated for immunogenicity in mice. Virus was purified by ultracentrifugation on 30% glycerol cushion followed by differential centrifugation on 10-60% sucrose gradient and inactivated with ß-propio lactone at a concentration of 1:3500. The inactivated product was blended with aluminium phosphate (3%) and immunized 4-week-old Swiss albino mice. Neutralizing antibodies in the range of 1:10 to 160 and 1:80 to 1:320 was detected with 85% and 100% sero-conversion after 2nd and 3rd dose, respectively. All the immunized mice with antibody titer above 1:20 survived live virus challenge. The vaccine candidate has potential to be an efficient vaccine against CHP virus.


Subject(s)
Vaccines, Inactivated/immunology , Vesiculovirus/immunology , Viral Vaccines/immunology , Animals , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , Chlorocebus aethiops , Immunization , Mice , Rhabdoviridae Infections/immunology , Rhabdoviridae Infections/prevention & control , Rhabdoviridae Infections/virology , Treatment Outcome , Vaccines, Inactivated/administration & dosage , Vero Cells , Vesiculovirus/pathogenicity , Vesiculovirus/physiology , Viral Vaccines/administration & dosage
15.
Trop Med Int Health ; 16(5): 585-8, 2011 May.
Article in English | MEDLINE | ID: mdl-21371218

ABSTRACT

OBJECTIVE: To identify the aetiological agent/s of an outbreak of chikungunya-like illness with high morbidity and several fatalities in Tamil Nadu, India, 2009-2010. METHODS: Two hundred and seventeen serum samples were collected from the affected areas and screened for chikungunya virus (CHIKV), dengue virus (DENV) and Japanese encephalitis virus (JEV) IgM antibodies using MAC-ELISA kits. A few selected samples were also tested for Ross River, Sindbis, and Murrey Valley viruses by RT-PCR and Hantan virus by serology. Twelve acute serum and mosquito samples were processed for virus isolation in C6/36 cells. CHIKV isolate was characterised by RT-PCR and sequencing. RESULTS: Diagnostic levels of IgM antibodies were detected in 107 (49.3%) CHIKV samples and 22 (10.1%) DENV samples. IgM antibodies against JEV were not detected (n=46). Characterisation of the CHIKV isolate at genetic level demonstrated it as ECSA (E1: 226A). Thirty-six selected samples were also negative for Ross River, Sindbis, Murrey Valley and Hantan viruses. CONCLUSION: High prevalence of CHIKV IgM antibody positivity, clinical symptoms, virus isolation and the presence of vector mosquitoes clearly suggest CHIKV as the aetiological agent responsible for the outbreak.


Subject(s)
Alphavirus Infections/diagnosis , Chikungunya virus/isolation & purification , Adolescent , Adult , Age Distribution , Alphavirus Infections/epidemiology , Alphavirus Infections/transmission , Animals , Antibodies, Viral/blood , Chikungunya virus/immunology , Child , Dengue/diagnosis , Diagnosis, Differential , Disease Outbreaks , Encephalitis, Japanese/diagnosis , Female , Humans , Immunoglobulin M/blood , India/epidemiology , Insect Vectors/parasitology , Male , Middle Aged , Reverse Transcriptase Polymerase Chain Reaction/methods , Young Adult
16.
Indian J Med Res ; 132: 155-9, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20716815

ABSTRACT

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 (TCID(50)) and indirect immunofluorescence 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.


Subject(s)
Culture Media/chemistry , Vesiculovirus/growth & development , Aedes , Animals , Cell Line, Tumor , Chickens , Chlorocebus aethiops , Fluorescent Antibody Technique, Indirect , Kinetics , Phlebotomus , Sus scrofa , Time Factors , Vero Cells
17.
Indian J Virol ; 21(1): 45-9, 2010 Jun.
Article in English | MEDLINE | ID: mdl-23637477

ABSTRACT

A real-time RT-PCR assay was standardized and evaluated for the detection of the recent pandemic 2009 H1N1 strain that circulated around the world causing colossal loss of human life. We amplified the conserved regions of the hemagglutinin (HA) gene of 438 clinical specimens using real-time RT-PCR assay for rapid identification of pandemic influenza virus. The real-time RT-PCR was optimized and the primers and probes were tested against a panel of known negative and positive controls. RNA isolated from the HeLa cell line served as quality control. The conventional RT-PCR which is an established method of influenza virus diagnosis was compared to real-time RT-PCR. Of 438 clinical specimens tested, 212 specimens were found positive for influenza A virus (SD 46.669) in which 139 specimens were diagnosed positive for the pandemic 2009 H1N1 while 73 were the seasonal influenza viruses. We report that the real-time RT-PCR assay offers both, a high sensitivity and specificity when compared with the traditional identification method. The real-time RT-PCR assay allows rapid identification of the pandemic swine 2009-H1N1 at very low viral loads that are negative by the traditional RT-PCR. This optimized assay can be a very useful tool to assist both epidemiologists and the clinicians.

18.
J Med Virol ; 82(2): 304-10, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20029807

ABSTRACT

Japanese encephalitis virus (JEV) induces an acute infection of the central nervous system, the pathogenic mechanism of which is not fully understood. To investigate host response to JEV infection, 14-day-old mice were infected via the extraneural route, which resulted in encephalitis and death. Mice that received JEV immune splenocyte transfer were protected from extraneural JEV infection. Pathology and gene expression profiles were then compared in brains of mice that either succumbed to JEV infection or were protected from infection by JEV immune cell transfer. Mice undergoing progressive JEV infection had increased expression of proinflammatory cytokines, chemokines, and signal transducers associated with the interferon (IFN) pathway. In contrast, mice receiving immune cell transfer had increased production of the Th2 cytokine IL-4, and of IL-10, with subdued expression of IFN-gamma. We observed IL-10 to be an important factor in determining clinical outcome in JEV infection. Data obtained by microarray analysis were further confirmed by quantitative RT-PCR. Together, these data suggest that JEV infection causes an unregulated inflammatory response that can be countered by the expression of immunomodulatory cytokines in mice that survive lethal infection.


Subject(s)
Cytokines/immunology , Cytokines/toxicity , Encephalitis Virus, Japanese/immunology , Encephalitis, Japanese/immunology , Encephalitis, Japanese/pathology , Adoptive Transfer , Animals , Brain/pathology , Brain/virology , Disease Models, Animal , Gene Expression Profiling , Humans , Inflammation/immunology , Leukocytes, Mononuclear/immunology , Mice , Mice, Inbred BALB C , Oligonucleotide Array Sequence Analysis , Reverse Transcriptase Polymerase Chain Reaction
19.
J Psychopharmacol ; 24(7): 1089-96, 2010 Jul.
Article in English | MEDLINE | ID: mdl-19164496

ABSTRACT

Adverse impact of atypical antipsychotic drugs on body weight of adult and juvenile groups has been well-documented both at clinical and preclinical investigations. However, studies on impact of drug on body weight during fetal or neonatal development received little attention. The present study is the first-ever preclinical investigation demonstrating the effect of lactational exposure of olanzapine (4, 8, and 10 mg/kg) and risperidone (1 and 2 mg/kg), two widely prescribed antipsychotics, on body weight of mice neonates. Body weight gain was observed with both the drugs, although a sex-related differential response was noted. In olanzapine-exposed female neonates, the weight gain was more with the highest dose. Male neonates showed a reverse trend, i.e. the highest gain with the lowest dose. Female neonates exposed to risperidone also showed significant, but less gain as compared to their olanzapine-exposed counterparts. Risperidone-exposed male neonates showed little body weight gain. Waist-to-hip ratio and plasma prolactin level were measured to explain the reason behind the body weight gain, but there were deviations with respect to drug and sex. The body weight gain may be the overall manifestations of drug-induced endocrine and metabolic dysregulations.


Subject(s)
Animals, Newborn/physiology , Antipsychotic Agents/pharmacology , Benzodiazepines/pharmacology , Body Weight/drug effects , Lactation/physiology , Milk/metabolism , Animals , Animals, Suckling , Female , Male , Mice , Olanzapine , Prolactin/blood , Risperidone/pharmacology , Sex Characteristics , Waist-Hip Ratio , Weight Gain/drug effects
20.
Indian J Med Res ; 130(5): 514-9, 2009 Nov.
Article in English | MEDLINE | ID: mdl-20090098

ABSTRACT

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


Subject(s)
Nairobi sheep disease virus/pathogenicity , Animals , Bunyaviridae Infections/transmission , Bunyaviridae Infections/virology , Female , Goats , Humans , India , Male , Mice , Nairobi Sheep Disease/virology , Nairobi sheep disease virus/genetics , Nairobi sheep disease virus/isolation & purification , Nairobi sheep disease virus/physiology , Sheep , Ticks/virology , Virus Replication , Zoonoses/transmission , Zoonoses/virology
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