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ABSTRACT: A study was conducted to examine the diversity in the VP7 genes of rotavirus strains circulating in adolescent and adult cases of acute gastroenteritis during two different time periods, 1993-1996 and 2004-2007. The multiplex RT-PCR carried out on 131 rotavirus positive fecal specimens detected 65 (49.6%) single and 48 (36.6%) mixed infections of VP7 genotypes that included 43G1 (38.1%), 37G2 (32.7%), 8G3 (7.1%), 15G4 (13.3%), and 10G9 (8.8%) specificities. Sequencing and phylogenetic analysis of the VP7 gene amplicons revealed the presence of G1-IA (4.7%), G1-IB (69.8%), and G1-IC (25.5%) lineages within the G1 strains, G2-IIb1 (70.3%) and G2-IIb2 (29.7%) lineages within G2 strains, G3-3S1 (12.5%) and G3-3S4 (87.5%) lineages within G3 strains, G4-Ia (6.7%) and G4-Ib (93.3%) lineages within G4 strains, and G9-III lineage within G9 strains. The variability within VP7 genotypes was evident by 1.4-8.0% and 1.3-3.9% amino acid divergence respectively from the prototype strains and between the groups of strains at the two time points. This is the first report describing the phylogenetic analysis of VP7 genes of rotaviruses from adolescent and adult cases of acute gastroenteritis in India. Since adults infected with rotavirus could act as a source of infection and affect the epidemiology of rotaviruses in children, genetic analysis of the rotavirus strains circulating in adults is required. The intragenotypic diversity within VP7 genes demonstrated by the present study highlights the need for constant surveillance of rotavirus infections to understand better the evolution and transmission of group A rotaviruses in the community.
Journal of Medical Virology 09/2012; 84(9):1481-8. · 2.82 Impact Factor
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ABSTRACT: The vast diversity within rotavirus strains circulating in the developing countries continues to be a major challenge for the efficacy of currently used preset rotavirus vaccines. The sequence analysis and phylogeny of multiple genes of rotavirus strains enable identification of reassortant strains and their human or animal origin. The objective of this study was to monitor the genetic linkage between the rotavirus VP4(P), VP6(I), VP7(G) and NSP4(E) encoding genes. The G, P, I and E genotypes of a total of 80 rotavirus strains isolated from adolescent and adult cases of acute gastroenteritis at the two time points [1993-1996 (n=67) and 2004-2007 (n=13)] were determined by nucleotide sequencing and phylogenetic analysis. The rotavirus strains from the 1990s and 2000s revealed common combinations of genotypes (G1-P[8]-I1-E1, G2-P[4]-I2-E2, G3-P[8]-I1-E1 and G4-P[8]-I1-E1) in 47.8% and 30.8%, unusual combinations of the same genotypes (G2-P[8]-I2-E2, G9-P[6]-I1-E1, G9-P[6]-I1-E2, G9-P[6]-I2-E1 and G4-P[4]-I1-E2, G1-P[4]-I2-E1, G9-P[4]-I1-E1) in 7.5% and 23% and mixed infections of different G and P genotypes in 31.3% and 46.2%, respectively. Discordance in the association of I with E, G with I and E and P with I and E genotypes was found to be contributed respectively by 23.8-38.5%, 40.3-69.8% and 49.3-61.5% of the rotavirus strains at the two time points. The data suggest relatively high occurrence of intergenogroup reassortment in circulating rotavirus strains emphasizing the need for continuous surveillance and whole genome sequence based characterization of rotavirus strains for better understanding of their evolution and ecology.
Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 08/2012; 12(8):1630-1634. · 3.22 Impact Factor
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ABSTRACT: To date, full-genome sequences of only seven human group B rotavirus (RVBs) strains have been described. Such data on more RVBs are necessary to establish the evolutionary relationship and ecological features of RVBs from different geographical regions. The present study was aimed at determining the full-length sequences of all 11 genes of 13 human RVB strains detected during 1995-2010 in sporadic and outbreak cases of acute gastroenteritis from four different cities of western India. This study also included estimation of evolutionary rates and site-specific selection pressure analysis for all gene segments. Nucleotide/deduced amino acid sequence analyses of structural and non-structural genes showed 95.1-99.8/94.1-100 % identity with the counterparts of RVB strains isolated in India, Bangladesh and Myanmar. Phylogenetic analyses of all gene segments revealed formation of a monophyletic clade of the western Indian RVB strains, reflecting their highly conserved nature. All gene segments were also found to be under negative/purifying selection pressure. These data suggest that RVB is circulating in the natural host as a series of stable viral clones. Estimates of rates of nucleotide substitution in all RVBs ranged from 1.36-4.78×10(-3) substitutions per site per year. The rate for human RVB VP7 and NSP2 genes were comparable, respectively, with the evolution kinetics of genotype G9/G12 and N1 group A rotavirus strains. The time of the most recent common ancestor of the extant human RVBs was estimated to be during 1915-1974. Evolutionary and genetic analyses carried out in this study provide data that is useful for the elucidation of evolutionary relationship/timescale, stasis or dynamics existing in the RVB population.
Journal of General Virology 07/2012; 93(Pt 10):2252-66. · 3.36 Impact Factor
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ABSTRACT: Diarrhoeal disease is the fifth leading cause of all mortality globally. To this burden, rotavirus contributes over half a million deaths annually. This pilot study was conducted to determine the economic burden of diarrhoeal episodes on families from different geographical regions accessing medical facilities in India.
Participants were enrolled from four study sites with eight reporting hospitals, categorized as non-profit and low cost, private and government facilities between November 2008 and February 2009. Questionnaires detailing healthcare utilization, medical and non-medical expenditure and lost income were completed by families of children < 5 yr of age hospitalized for gastroenteritis. All available faecal samples were tested for rotavirus.
A total of 211 patients were enrolled. The mean total cost of a hospitalized diarrhoeal episode was ` 3633 (US$ 66.05) for all facilities, with a marked difference in direct costs between governmental and non-governmental facilities. Costs for rotavirus positive hospitalizations were slightly lower, at ` 2956 (US$ 53.75). The median cost of a diarrhoeal episode based on annual household expenditure was 6.4 per cent for all-cause diarrhoea and 7.6 per cent for rotavirus diarrhoea. Of the 124 samples collected, 66 (53%) were positive for rotavirus.
Data on direct costs alone from multiple facilities show that diarrhoeal disease constitutes a large economic burden on Indian families. Affordable, effective vaccines would greatly reduce the economic burden of severe gastroenteritis on patients, families and the government.
The Indian journal of medical research 07/2012; 136(1):68-73. · 1.84 Impact Factor
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ABSTRACT: Hand, foot and mouth disease (HFMD), a common contagious disease that usually affects children, can be caused by enteroviruses. Coxsackievirus A16 (CV-A16) and enterovirus 71(EV-71) are the major aetiological agents of HFMD. Other EV serotypes, CV-A4-7, CV-A9-10, CV-B1-3, CV-B5, E-4 and E-19, have also been found associated with both sporadic infections and outbreaks of HFMD. In India, outbreaks of HFMD have been documented; however, molecular characterization of the aetiological agents has rarely been reported. Cases of HFMD were identified during 2009-2010 on the basis of clinical features in southern and eastern parts of India. The aim of the present study was to detect and characterize the aetiological agents associated with the disease. A total of 89 specimens consisting of 41 sera, 24 vesicular fluids, 18 stools and 6 throat swabs were collected from 61 clinically diagnosed HFMD cases from southern and eastern parts of India. RT-PCR followed by sequencing of PCR amplicons and phylogenetic analysis were performed on all specimens for detection of EV RNA and identification of EV types. EV RNA was detected in 47.1 % (42/89) of the specimens collected from 57.4 % (35/61) of the HFMD cases. Thirty-six of 42 EV strains showed amplification of the VP1/2A junction or VP1 regions. Sequence analysis of the amplicons identified the presence of CV-A16 (54.8 %), CV-A6 (38.1 %), EV-71 (2.4 %), CV-A10 (2.4 %) and E-9 (2.4 %) serotypes in the HFMD cases. The study documents CV-A16 and CV-A6 as major and CV-A10, EV-71 and E-9 as rare viral pathogens of HFMD in India.
Journal of Medical Microbiology 11/2011; 61(Pt 3):420-5. · 2.50 Impact Factor
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ABSTRACT: To characterize VP4, VP6, VP7 and NSP4 genes of representative GBR strains (NIV-005625, NIV-04622 and NIV-094456) detected as the major etiologic agent in the outbreaks of gastroenteritis in western India.
Fecal specimens collected during the outbreaks of gastroenteritis were processed for RNA isolation, RT-PCR using GBR VP4, VP6, VP7 and NSP4 gene specific primers, nucleotide sequencing of the amplicons and phylogenetic analysis of the sequences.
Phylogenetic analysis of all of the VP4, VP6, VP7 and NSP4 gene sequences revealed clustering of GBR strains in Indian-Bangladeshi lineage of genotype G2 with 95.8%-99.4% nucleotide and 97.3%-100.0% amino acid identities. However, all three strains showed the presence of unique amino acid substitutions in the VP4 protein suggesting alteration in the antigenicity of outbreak strains of GBR. The VP8* and VP5* regions of VP4 proteins showed respectively 0.5%-6.3% and 0.2%-1.1% amino acid divergence from human GBR strains of Indian-Bangladeshi lineage.
These data confirm the reported variability of VP8* region and suggest the possible role of this region in the perpetuation of GBR infections in the environment. This is the first study to document the phylogenetic relationship of VP4, VP6, VP7 and NSP4 genes of GBR strains detected in the outbreaks of gastroenteritis from India with the GBR strains from other parts of world.
Asian Pacific Journal of Tropical Medicine 11/2011; 4(11):846-9. · 0.37 Impact Factor
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ABSTRACT: To conduct a comparative analysis of the VP4 gene sequences of Indian wild type (06361, 0613158, 061060 and 0715880) and cell culture adapted (06361-CA, 0613158-CA, 061060-CA and 0715880-CA) G1P[8] rotavirus strains.
Full-length VP4 genes of each of the four wild type G1P[8] rotavirus strains and their cell culture adapted counterparts displaying consistent cytopathic effect were subjected to RT-PCR amplification and nucleotide sequencing.
All four cell culture adapted G1P[8] rotavirus strains showed nucleotide and amino acid substitutions in the VP4 gene as compared to their wild type strains. The number of substitutions however, varied from 1-64 and 1-13 respectively. The substitutions were distributed in both VP5* and VP8* subunits of VP4 gene respectively of permeabilization and hemagglutinating activity. The presence of unique amino acid substitutions was identified in two of the four wild type (V377G, S387N in 061060 and I644L in 0715880) and all four cell culture adapted (A46V in 0613158-CA, T60R in 06361-CA, L237V, G389V and Q480H in 061060-CA and S615G and T625P in 0715880-CA) strains for the first time in the VP4 gene of P[8] specificity. Amino acid substitutions generated increase in the hydrophilicity in the cell culture adapted rotavirus strains as compared to their corresponding wild type strains.
Amino acid substitutions detected in the VP4 genes of G1P[8] rotavirus strains from this study together with those from other studies highlight occurrence of only strain and/or host specific substitutions during cell culture adaptation. Further evaluation of such substitutions for their role in attenuation, immunogenicity and conformation is needed for the development of newer rotavirus vaccines.
Asian Pacific Journal of Tropical Medicine 07/2011; 4(7):541-6. · 0.37 Impact Factor
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ABSTRACT: Rotavirus G1P[8] strains are the most predominant cause of rotavirus diarrhea, worldwide and are an important component of currently licensed RotaTeq and Rotarix vaccines. Despite a significant contribution of these strains in causing diarrhea in Indian children, none of them has been characterized completely, to date. This issue was addressed in the present study by sequencing and phylogenetic analysis of complete genomes of 3 Indian rotavirus strains (06361, 0613158 and 061060) of G1P[8] specificity. Genotype of G1P[8] I1R1C1M1A1N1T1E1H1 respectively, for the VP7, VP4, VP6, VP1, VP2, VP3, NSP1, NSP2, NSP3, NSP4 and NSP5 genes was assigned to all of the three strains. The sequence analysis of structural and nonstructural genes indicated genetic relatedness (94-99.5%) with recently circulating strains and divergence (2.4-15.6%) with old prototype strains. Phylogenetic analysis revealed that new strains (Western Indian rotavirus strains and recently isolated strains--Dhaka16-03 (G1P[8]), Dhaka25-02 (G12P[8]), Matlab13-03 (G12P[6]), B3458 (G9P[8]), Matlab36-03 (G11P[8]), and B4633-03 (G12P[8]) and old prototype strains (KU and Wa) clustered in the same lineages of VP1, VP2, VP3, NSP2 and NSP4 genes however, grouped separately in VP6, NSP1 and NSP5 genes with 10-11%, 15.6-16.7% and 6.3-7.5% nucleotide sequence divergence, respectively. These results suggest that the rotavirus VP6, NSP1 and NSP5 genes of Wa-like rotaviruses are more prone to temporal mutations. Both structural and nonstructural genes of the Western Indian rotavirus strains shared nucleotide and amino acid substitutions with the Bangladeshi strain, Dhaka16-03 (G1P[8]) in the year 2003. This study documents for the first time the phylogenetic and evolutionary relationships of Indian G1P[8] rotavirus strains with the rotavirus strains from other parts of world and provides data useful for the evaluation of rotavirus vaccine programs.
Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 01/2011; 11(2):504-11. · 3.22 Impact Factor
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ABSTRACT: Experimental studies of human rotavirus infections in mice are limited and there is lack of information on the quantitative assessment of rotaviral replication and its relationship with histological changes. In the present study, consequences of human rotavirus strain, YO induced gastroenteritis in infant BALB/c mice were analyzed for the occurrence of clinical symptoms, histopathology and virological events. The infected animals developed diarrhea and dehydration and showed accumulation of vacuolated enterocytes with lodging of the rotavirus antigens and shortening of villi in the intestine over a period of 5 days. The ileum was identified as the most susceptible and supportive part of small intestine for perpetuation of rotavirus infection in mice. Rotaviral antigen/RNA in stool and RNA in intestine were detected throughout the clinical disease period. At 48-72 h post inoculation, diarrhea was at the peak (90-95%) in the infected animals with increased load of viral RNA and intense pathological lesions suggesting it as the critical time point in the course of infection. The rising titers of antirotavirus neutralizing antibodies ascertained the replication of human rotavirus strain, YO in mice. These data may contribute to the understanding of pathophysiological, immunological and virological characteristics of rotavirus infections in mice.
Microbes and Infection 12/2010; 13(4):331-8. · 3.10 Impact Factor
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Journal of Medical Virology 11/2010; 82(11):1983. · 2.82 Impact Factor
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ABSTRACT: Noroviruses (NoVs) are considered as important causative agents of non-bacterial acute gastroenteritis, worldwide. The data on NoV genomes, their diversity and evolution from Indian subcontinent are not available to date. The present study describes the characterization of full-length genomes of Indian NoV strains for the first time to establish their phylogenetic and evolutionary relationship with those circulating worldwide. Amplification of full-length genomes of three NoV strains (PC15, PC51 and PC52) was carried out using nine overlapping sets of forward and reverse primers. Full-length genomes of all of the three strains were characterized by phylogenetic, SimPlot, selection pressure and hydrophilicity analyses. The strain, PC15 was placed in the GII.4-Hunter subcluster. An intragenotype recombination event between ORFs 2 (new GII.4 variant) and 3 (Den Haag subcluster) of the strain, PC51 was detected for the first time in this study. The strain, PC52 showed the presence of commonly detected intergenotype recombination, GII.b/GII.3. A 16 amino-acid signature code (TDVVYYAGASQPRDDI) was identified in the ORF2 of recombinant GII.3 specificity strains, which may serve as a genetic marker for differentiation of these strains from non-recombinant GII.3 strains. The amino-acid substitutions in the ORF2 of PC51 and PC52 strains in comparison to the reference strains (Toyama1 and TV24) resulted in an increase in the hydrophilicity suggested alterations in the antigenic regions of Indian NoV strains. A unique pattern of amino-acid substitutions was observed within seven subclusters of GII.4 at 19 sites (including 13 sites under positive selection pressure) spanning entire ORF2. The study indicates adaptation of NoVs in the environment to escape the host immune response and to persist in the population. It also provides in-depth analyses of NoV genomes from India and determines the extent of conserved and variable features of the Indian NoV strains.
Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 10/2010; 10(7):1101-9. · 3.22 Impact Factor
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ABSTRACT: NSP4 and VP6 genes of a total of 118 rotavirus strains detected in adolescent and adult cases of acute gastroenteritis (AGE) in 1993-1996 and 2004-2007 were characterized to determine their diversity and genetic linkage. Eighty-two percent and 89% of the strains showed amplification of NSP4 and VP6 genes respectively in RT-PCR. Sequencing and phylogenetic analysis of the VP6 genes showed distribution of genogroups in the lineages I-1 (1.4%), I-2 (50.7%) and II-4 (47.9%) in the 1990s and I-2 (73.5%) and II-4 (26.5%) in 2000s, indicating diversity in genogroups at both time points. Amino acid divergence within the genogroup II strains from 1990s and genogroup I strains from the 2000s was noteworthy (4.7-6.7%). Sequencing and phylogenetic analysis of the NSP4 genes showed almost equal distribution (45.0-55.0%) of genotypes A and B however, higher amino acid divergence within the genotype B strains (up to 9.3%) than in genotype A strains (up to 2.9%) at the two-time points. Nearly 70% of the strains showed NSP4-A-VP6-I or NSP4-B-VP6-II genetic linkage. The discordance in the linkage noted in 29.7% of the strains was predominated by NSP4-B and VP6-I combination and appeared strikingly high in the infections caused by unusual and mixed rotavirus strains. This is the first report to describe the phylogenetic analysis of rotavirus NSP4 and VP6 genes and their discordance in adolescent and adult cases with AGE from India. The extensive diversity within the rotavirus genes and their relationship revealed by this study emphasizes the need for evaluation of the rotavirus vaccines being used currently.
Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 10/2010; 10(7):940-9. · 3.22 Impact Factor
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ABSTRACT: A total of 78 fecal specimens were collected from both apparently healthy (n=71) and diarrheic (n=7) cattle from an organized farm in Pune, western India in December 2007-January 2008. Three specimens tested positive for group A rotavirus (RV) by antigen capture ELISA were subjected to RT-PCR for amplification of entire coding regions of three structural (VP4, VP6 and VP7) and one nonstructural (NSP4) genes. All three strains were genotyped as G8P[14]. Phylogenetic analysis of the VP7 and VP4 genes showed clustering of the VP7 gene with G8 strains of bovine origin and VP4 gene with P[14] strains of human origin. The identification of VP6 and NSP4 genes to have I2 (subgroup I) and E2 (genotype A) specificity, respectively of bovine and human origin indicated independent segregation of genes in bovine RV strains. This study indicates circulation of a rare RV genotype, G8P[14] in western India. To our knowledge, this is the second report on RV G8[14] isolated from bovine species after bovine group A RV strain, SUN9 from Japan.
Veterinary Microbiology 09/2010; 148(2-4):384-8. · 3.33 Impact Factor
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ABSTRACT: 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 (<or=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 <or=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.
Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 05/2010; 10(4):575-9. · 3.22 Impact Factor
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ABSTRACT: The molecular characteristics of hepatitis A virus (HAV) have been studied widely though there is a paucity of data on the correlation with virological and serological findings. In the present study, the whole genome of an Indian HAV strain associated with Guillain-Barré syndrome (GBS) was characterized vis-à-vis two other Indian HAV genotype IIIA strains, associated with a self-limiting disease. The percentage nucleotide divergence displayed by the Indian strains (CP-IND, PN-IND, and GBS-IND) varied from 3 to 6, whereas the percentage amino acid divergence varied from 0.1 to 0.7 as compared to the other HAV IIIA strains (n = 5) available in the GenBank. The GBS-IND strain showed an increased rate of nonsynonymous substitutions as well as a larger number of unique and heterologous amino acid substitutions compared to the HAV IIIA GenBank strains. These amino acid substitutions in the GBS-IND strain were detected in a nonstructural protein (2C-251F) and the B-cell epitope regions of structural proteins (VP1-29E, VP1-91S, VP3-50Y, and VP4-5S). In a comparative analysis of HAV strains, homology-based models of the capsid proteins indicated a localized alteration in the surface charge distribution on the VP1 protein of GBS-IND strain and involvement of its unique amino acid substitutions in the predicted antigenic determinants. Overall, the study suggests that the unique amino acid substitutions in the GBS-IND strain may have contributed to neutralization escape of the virus leading to a longer duration of viremia.
Journal of Medical Virology 05/2010; 82(6):913-9. · 2.82 Impact Factor
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ABSTRACT: A total of 1,591 fecal specimens were collected in 1993-1996 and 2004-2007 from adolescents and adults with acute gastroenteritis in Pune, India for detection and characterization of rotavirus. At the two time points, group A rotavirus was detected in 8.6% and 16.2% of the adolescents and 5.2% and 17.2% of the adults, respectively. Reverse transcription-PCR with consensus primers followed by multiplex genotyping PCR detected common strains G1P[8], G2P[4], G3P[8], and G4P[8] in a total of 53.1% of the samples from 1993 to 1996, while the only prevalent strain identified in 2004-2007 was G2P[4] (23.5% of total). Uncommon rotavirus strains (G1P[4], G2P[8] G9P[6]/P[4]) increased from 7.8% (1993-1996) to 41.2% (2004-2007), while the prevalence of mixed rotavirus infections was high (39%/35%) at both time points. Mixed infections detected by multiplex PCR were confirmed by sequencing two or more individual genotype-specific PCR products of the VP7 and VP4 genes from the same sample. Phylogenetic analysis of the sequences showed circulation of a heterogeneous rotavirus strain population comprising genotypes G1 (lineages I and IIb), G2 (lineages I and IIb), G4 (lineage Ia), P[4] (lineages P[4]-5 and P[4]-1), P[8] (lineages P[8]-II and P[8]-III), and P[6] (M37-like lineage). The VP6 gene sequences of the nontypeable strains were most homologous to animal strains. This study documents the molecular epidemiology of rotavirus strains in adolescents and adults in India, and suggests that it may be important to monitor these strains over time for the potential impact on rotavirus vaccines under development for use in the Indian population. J. Med. Virol. 82:519-527, 2010. (c) 2010 Wiley-Liss, Inc.
Journal of Medical Virology 03/2010; 82(3):519-27. · 2.82 Impact Factor
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Gagandeep Kang,
Rashmi Arora, Shobha D Chitambar,
Jagdish Deshpande,
M D Gupte,
Madhuri Kulkarni,
Trilok N Naik,
Dipali Mukherji,
S Venkatasubramaniam,
Jon R Gentsch,
Roger I Glass,
Umesh D Parashar
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ABSTRACT: Current, nationally representative data on rotavirus disease burden and rotavirus strains in India are needed to understand the potential health benefits of rotavirus vaccination.
The Indian Rotavirus Strain Surveillance Network was established with 4 laboratories and 10 hospitals in 7 different regions of India. At each hospital, children aged <5 years who presented with acute gastroenteritis and required hospitalization with rehydration for at least 6 h were enrolled. A fecal specimen was obtained and was tested for rotavirus with use of a commercial enzyme immunoassay, and strains were characterized using reverse-transcription polymerase chain reaction.
From December 2005 through November 2007, rotavirus was found in approximately 39% of 4243 enrolled patients. Rotavirus was markedly seasonal in northern temperate locations but was less seasonal in southern locations with a tropical climate. Rotavirus detection rates were greatest among children aged 6-23 months, and 13.3% of rotavirus infections involved children aged <6 months. The most common types of strains were G2P[4] (25.7% of strains), G1P[8] (22.1%), and G9P[8] (8.5%); G12 strains were seen in combination with types P[4], P[6], and P[8] and together comprised 6.5% of strains.
These data highlight the need for development and implementation of effective prophylactic measures, such as vaccines, to prevent the large burden of rotavirus disease among Indian children.
The Journal of Infectious Diseases 11/2009; 200 Suppl 1:S147-53. · 6.41 Impact Factor
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ABSTRACT: The phenomenon of recombination has been widely described among noroviruses (NoVs) in the past few years. In a NoV surveillance study conducted in western India, 3 novel and 3 known combinations of RNA-dependent RNA polymerase (RdRp) and capsid genes were identified in genogroup (G) II NoV strains. The present study pertains to the characterization of three novel intergenotype NoV GII recombinant strains. RT-PCRs were carried out for the amplification of nearly complete RdRp and complete capsid genes spanning ORF1/2 overlap of three strains followed by sequencing of the amplicons. The recombination event was confirmed by phylogenetic analysis using Bayesian MCMC approach, SimPlot analysis and Maximum chi(2) method. Three novel intergenotype (GII) recombinations of GII.b/GII.18, GII.1/GII.12 and GII.3/GII.13 specificities were identified respectively in the strains PC03, PC24 and PC25 for the first time. The breakpoint in the novel recombinants was placed in the vicinity of the 20 bp ORF1/2 overlap, a common hotspot known to exist in NoV recombinants. The capsid genes of all of the 3 recombinants were closely related to their counter parts in reference strains however, a high degree of variation emerged in the polymerase genes especially of PC24 and PC25 in comparison to the reference strains.
Virus Research 11/2009; 147(2):242-6. · 2.94 Impact Factor
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ABSTRACT: This study pertains to the characterization of a human rotavirus strain (NIV929893) with a rare specificity of G1P[19]. Three structural genes (VP4, VP6 and VP7) and one non-structural gene (NSP4) of strain NIV929893 were subjected to RT-PCR for amplification of entire coding regions. All of the amplicons were sequenced to carry out phylogenetic analysis. The complete amino acid sequences of the VP7 and VP4 gene products showed clustering of the VP7 gene with G1 strains of human origin and the VP4 gene with P[19] strains of porcine origin. The two viral proteins VP6 and NSP4, described previously as genetically linked proteins, were shown to be subgroup II and genotype B of human and porcine origins, respectively. The findings of this study provide evidence of reassortment between VP7/VP6 genes of humans and VP4/NSP4 genes of porcine species and an independent segregation of VP6 and NSP4 genes in a group A human rotavirus strain with G1P[19] specificity.
Journal of Medical Microbiology 09/2009; 58(Pt 12):1611-5. · 2.50 Impact Factor
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ABSTRACT: The rotavirus (RV) G1 strains represent the common genotype that causes diarrhea in humans. The aim of this study was to determine the genetic lineages of G1 RV strains circulating in western India during two different time periods, 1991-1994 and 2006 by molecular characterization of VP7 genes. The phylogenetic analysis of VP7 genes showed clustering of G1 strains into lineages I (96.4%) and VIII (3.6%) in 1991-1994 and I (96.2%) and II (3.8%) in 2006. The sublineage IA was predominant (96.4%) in the years 1991-1994, however, was detected only in 44.4% of the strains in 2006 co-circulating with other sublineages IB (44.4%), IC (3.7%), IE (3.7%) and IIB (3.7%). The amino acid substitutions were noted in the previously identified signature codes of sublineages IB and IIB at positions 75 and 55, respectively. The differentiation marker (Q) described for sublineage IB at position 16 was replaced by I in all Indian strains clustered in sublineage IB. The study reports the characterization of G1 RV strains on the basis of distinct lineages and sublineages from India and emphasizes continuous monitoring on the diversity of G1 strains across the Indian population.
Virus Research 09/2009; 146(1-2):36-40. · 2.94 Impact Factor
