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Cuevas JM, Combe M, Torres-Puente M, Garijo R, Guix S, Buesa J, Rodríguez-Díaz J, Sanjuán R. Human norovirus hyper-mutation revealed by ultra-deep sequencing. INFECTION GENETICS AND EVOLUTION 2016; 41:233-239. [PMID: 27094861 PMCID: PMC7172324 DOI: 10.1016/j.meegid.2016.04.017] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 04/11/2016] [Accepted: 04/15/2016] [Indexed: 02/02/2023]
Abstract
Human noroviruses (NoVs) are a major cause of gastroenteritis worldwide. It is thought that, similar to other RNA viruses, high mutation rates allow NoVs to evolve fast and to undergo rapid immune escape at the population level. However, the rate and spectrum of spontaneous mutations of human NoVs have not been quantified previously. Here, we analyzed the intra-patient diversity of the NoV capsid by carrying out RT-PCR and ultra-deep sequencing with 100,000-fold coverage of 16 stool samples from symptomatic patients. This revealed the presence of low-frequency sequences carrying large numbers of U-to-C or A-to-G base transitions, suggesting a role for hyper-mutation in NoV diversity. To more directly test for hyper-mutation, we performed transfection assays in which the production of mutations was restricted to a single cell infection cycle. This confirmed the presence of sequences with multiple U-to-C/A-to-G transitions, and suggested that hyper-mutation contributed a large fraction of the total NoV spontaneous mutation rate. The type of changes produced and their sequence context are compatible with ADAR-mediated editing of the viral RNA. Norovirus U-to-C hyper-mutants are present in patient samples. Analysis of hyper-mutants in cell culture suggests ADAR-mediated RNA edition. Hyper-mutation may contribute to norovirus diversity and evolution.
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Affiliation(s)
- José M Cuevas
- Instituto Cavanilles de Biodiversidad y Biología Evolutiva, Universitat de València, Valencia, Spain
| | - Marine Combe
- Instituto Cavanilles de Biodiversidad y Biología Evolutiva, Universitat de València, Valencia, Spain
| | - Manoli Torres-Puente
- Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat Valenciana, Valencia, Spain
| | - Raquel Garijo
- Instituto Cavanilles de Biodiversidad y Biología Evolutiva, Universitat de València, Valencia, Spain
| | - Susana Guix
- Departament de Microbiologia, Universitat de Barcelona, Barcelona, Spain
| | - Javier Buesa
- Departament de Microbiologia, Universitat de València, Valencia, Spain
| | | | - Rafael Sanjuán
- Instituto Cavanilles de Biodiversidad y Biología Evolutiva, Universitat de València, Valencia, Spain; Departament de Genètica, Universitat de València, Valencia, Spain.
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Thongprachum A, Khamrin P, Maneekarn N, Hayakawa S, Ushijima H. Epidemiology of gastroenteritis viruses in Japan: Prevalence, seasonality, and outbreak. J Med Virol 2015; 88:551-70. [PMID: 26387663 DOI: 10.1002/jmv.24387] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/16/2015] [Indexed: 12/11/2022]
Abstract
Acute gastroenteritis has been recognized as one of the most common diseases in humans and continues to be a major public health problem worldwide. Several groups of viruses have been reported as the causative agents of acute gastroenteritis, including rotavirus, norovirus, sapovirus, human astrovirus, adenovirus, and an increasing number of others which have been reported more recently. The epidemiology, prevalence, seasonality, and outbreaks of these viruses have been reviewed in a number of studies conducted in Japan over three decades. Rotavirus and norovirus were the two most common viruses detected almost equally in children under 5 years of age who were suffering from acute gastroenteritis. Like many other countries, the main rotavirus strains circulating in pediatric patients in Japan are G1P[8], G2P[4], G3P[8], and G9P[8]. Norovirus GII.4 was involved in most outbreaks in Japan and found to be associated with the emergence of new variants Sydney_2012. The classic human astrovirus, MLB, and VA clades astroviruses were also commonly found in pediatric patients with acute diarrhea. The sapovirus and adenovirus have been identified as the minor viral causative agents for acute gastroenteritis in Japan.
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Affiliation(s)
- Aksara Thongprachum
- Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, Japan.,Department of Developmental Medical Sciences, School of International Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Pattara Khamrin
- Faculty of Medicine, Department of Microbiology, Chiang Mai University, Chiang Mai, Thailand
| | - Niwat Maneekarn
- Faculty of Medicine, Department of Microbiology, Chiang Mai University, Chiang Mai, Thailand
| | - Satoshi Hayakawa
- Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, Japan
| | - Hiroshi Ushijima
- Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, Japan.,Department of Developmental Medical Sciences, School of International Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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Siqueira JAM, Linhares ADC, de Carvalho TCN, Aragão GC, Oliveira DDS, Dos Santos MC, de Sousa MS, Justino MCA, Mascarenhas JDP, Gabbay YB. Norovirus infection in children admitted to hospital for acute gastroenteritis in Belém, Pará, Northern Brazil. J Med Virol 2013; 85:737-44. [PMID: 23359323 DOI: 10.1002/jmv.23506] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/22/2012] [Indexed: 11/05/2022]
Abstract
Noroviruses are the leading cause of epidemic, non-bacterial outbreaks of acute gastroenteritis, and are also a major cause of sporadic acute gastroenteritis in infants. The aim of the present study was to identify norovirus infections in children not infected by rotavirus admitted to hospital for acute gastroenteritis in Belém. A total of 348 fecal specimens were obtained from children with diarrhea aged less than 5 years, all of whom had tested negative for rotavirus, between May 2008 and April 2010. Fecal samples were screened for norovirus antigen using enzyme-immunoassay (EIA). Specimens were subjected to reverse-transcription polymerase chain reaction (RT-PCR) using the primers Mon432/434-Mon431/433 for detection of the GI and GII norovirus strains, respectively. Based on both methods, the overall norovirus positivity rate was 36.5% (127/348). Of the 169 samples collected in the first year, 44.4% (n = 75) tested positive for norovirus using both methods, 35.5% (n = 60) by EIA and 40.8% (n = 69) by RT-PCR. Using RT-PCR as a reference standard, a sensitivity of 78.3%, specificity of 94%, and agreement of 87.6% were recorded. Genome sequencing was obtained for 22 (31.9%) of the 69 positive samples, of which 90.9% (20/22) were genotype GII.4d and 9.1% (2/22) were genotype GII.b. Norovirus infection was most frequent in children under 2 years of age (41.5%-115/277). The peak incidence (62.1%) of norovirus-related acute gastroenteritis in these patients (not infected by rotavirus) was observed in February 2010. These findings emphasize the importance of norovirus as a cause of severe acute gastroenteritis among children in Belém, Pará, Northern Brazil.
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Detection of a novel recombinant strain of norovirus in an African-descendant community from the Amazon region of Brazil in 2008. Arch Virol 2012; 157:2389-92. [PMID: 22872050 DOI: 10.1007/s00705-012-1428-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Accepted: 06/15/2012] [Indexed: 11/27/2022]
Abstract
Noroviruses, a major cause of acute gastroenteritis outbreaks worldwide, are constantly evolving. This ability is reflected in the speed and efficiency with which these viruses spread and remain in the human population. The present study reports the detection of a novel recombination event among norovirus genotypes in Brazil in 2008. A strain detected in a stool sample from a child with norovirus-associated gastroenteritis, residing in an African-descendant semi-closed community of Pará State, was characterized as a novel intergenotype recombinant, GII.7/GII.20, as determined by partial sequencing and SimPlot analysis.
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Simultaneous detection of seven enteric viruses associated with acute gastroenteritis by a multiplexed Luminex-based assay. J Clin Microbiol 2012; 50:2384-9. [PMID: 22518865 DOI: 10.1128/jcm.06790-11] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rapid and broad diagnostic methods are needed for the identification of viral agents of gastroenteritis. In this study, we used Luminex xMAP technology to develop a multiplexed assay for the simultaneous identification of major enteric viral pathogens, including rotavirus A (RVA), noroviruses (NoVs) (including genogroups GI and GII), sapoviruses (SaV), human astrovirus (HAstV), enteric adenoviruses (EAds), and human bocavirus 2 (HBoV2). The analytical sensitivity allowed detection of 10(3) (EAds, HBoV2, and RVA) and 10(4) (NoV GI and GII, SaV, and HAstV) copies per reaction mixture. Compared to conventional PCR, the Luminex-based assay yielded greater than 75% sensitivity and 97% specificity for each virus, and the kappa correlation for detection of all viruses ranged from 0.75 to 1.00. In conclusion, this multiplexed Luminex-based assay provides a potentially rapid, high-throughput, and maneuverable diagnostic tool for major viral pathogens associated with gastroenteritis.
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Le Guyader FS, Atmar RL, Le Pendu J. Transmission of viruses through shellfish: when specific ligands come into play. Curr Opin Virol 2012; 2:103-10. [PMID: 22440973 PMCID: PMC3839110 DOI: 10.1016/j.coviro.2011.10.029] [Citation(s) in RCA: 123] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Revised: 10/27/2011] [Accepted: 10/31/2011] [Indexed: 01/07/2023]
Abstract
Shellfish are known as vectors for human pathogens and despite regulation based on enteric bacteria they are still implicated in viral outbreaks. Among shellfish, oysters are the most common vector of contamination, and the pathogens most frequently involved in these outbreaks are noroviruses, responsible for acute gastroenteritis in humans. Analysis of shellfish-related outbreak data worldwide show an unexpected high proportion of NoV GI strains. Recent studies performed in vitro, in vivo and in the environment indicate that oysters are not just passive filters, but can selectively accumulate norovirus strains based on viral carbohydrate ligands shared with humans. These observations contribute to explain the GI bias observed in shellfish-related outbreaks compared to other outbreaks.
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Affiliation(s)
| | - Robert L Atmar
- Department of Medicine, Baylor College of Medicine, 1 Baylor Plaza, MS BCM 280, Houston, TX 77030, USA
| | - Jacques Le Pendu
- INSERM, U892, Université de Nantes, Institut de Recherche Thérapeutique, 8 quai Moncousu BP 70721, 44007 Nante Cedex 1, France
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Abstract
Norovirus (NoV) is the most common cause of infectious gastroenteritis in the world. Gastroenteritis caused by bacterial and parasitic pathogens is commonly linked to food sources, but the link between NoV and contaminated foods has been more difficult to establish. Even when epidemiological information indicates that an outbreak originated with food, the presence of NoV in the suspect product may not be confirmed. If food is found to contain a common strain of NoV that circulates widely in the community, it is not possible to use strain typing to link the contamination to patient cases. Although food is certainly implicated in NoV spread, there are additional person-to-person and fomite transmission routes that have been shown to be important. NoV has an extremely low infectious dose, is stable in the environment, and resists disinfection. Cell culture methods are not available, so viability cannot be determined. Finally, many NoV outbreaks originate with when an infected food handler contaminates ready-to-eat food, which can be interpreted as foodborne or person-to-person transmission. This review will discuss both the physical characteristics of NoVs and the available epidemiological information with particular reference to the role of foods in NoV transmission.
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Affiliation(s)
- Kirsten Mattison
- Bureau of Microbial Hazards, Health Canada, PL2204E, Ottawa, Ontario, Canada.
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Apelt N, Hartberger C, Campe H, Löscher T. The Prevalence of Norovirus in returning international travelers with diarrhea. BMC Infect Dis 2010; 10:131. [PMID: 20500860 PMCID: PMC2887448 DOI: 10.1186/1471-2334-10-131] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Accepted: 05/25/2010] [Indexed: 01/10/2023] Open
Abstract
Background There is a high incidence of diarrhea in traveling populations. Norovirus (NV) infection is a common cause of diarrhea and is associated with 7% of all diarrhea related deaths in the US. However, data on the overall prevalence of NV infection in traveling populations is limited. Furthermore, the prevalence of NV amongst travelers returning to Europe has not been reported. This study determined the prevalence of NV among international travelers returning to Germany from over 50 destinations in and outside Europe. Methods Stool samples of a total of 104 patients with a recent (< 14days) history of international travel (55 male, mean age 37 yrs.) were tested for the presence of NV genogroup (GG) I and II infection using a sensitive and well established quantitative RT PCR method. 57 patients experienced diarrhea at the time of presentation at the Department of Infectious Diseases & Tropical Medicine. The remaining 47 patients had no experience of diarrhea or other gastrointestinal symptoms for at least 14 days prior to their date of presentation at our institute. Results In our cohort, NV infection was detected in 15.7% of returning travelers with diarrhea. The closer to the date of return symptoms appeared, the higher the incidence of NV, ranging as high as 21.2% within the first four days after return. Conclusions In our cohort, NV infection was shown to be frequent among returning travelers especially in those with diarrhea, with over 1/5 of diarrhea patients tested positive for NV within the first four days after their return to Germany. Due to this prevalence, routine testing for NV infection and hygienic precautions may be warranted in this group. This is especially applicable to patients at an increased risk of spreading the disease, such as healthcare workers, teachers or food-handlers.
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Affiliation(s)
- Nadja Apelt
- Department of Infectious Diseases and Tropical Medicine, Ludwig-Maximilians University of Munich, Georgenstr. 5, 80799 Munich, Germany.
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Single-strand conformation polymorphism analysis for the study of adenoviral diversity in urban rivers. J Virol Methods 2010; 165:145-50. [DOI: 10.1016/j.jviromet.2010.01.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2009] [Revised: 12/21/2009] [Accepted: 01/21/2010] [Indexed: 11/22/2022]
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10
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Khamrin P, Takanashi S, Chan-It W, Kobayashi M, Nishimura S, Katsumata N, Okitsu S, Maneekarn N, Nishio O, Ushijima H. Immunochromatography test for rapid detection of norovirus in fecal specimens. J Virol Methods 2009; 157:219-22. [PMID: 19138707 DOI: 10.1016/j.jviromet.2008.12.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2008] [Revised: 12/11/2008] [Accepted: 12/15/2008] [Indexed: 10/21/2022]
Abstract
An immunochromatography (IC) assay for rapid detection of norovirus (NoV) was evaluated with fecal samples collected from children who suffered from acute gastroenteritis during the winter season of 2007-2008 in Japan. A total of 75 fecal specimens were tested for NoV by the newly developed IC kit and by a gold standard RT-PCR method. The sensitivity, specificity, and agreement of this IC kit were 75.4%, 100%, and 80%, respectively. In addition, phylogenetic analysis revealed that the majority of NoV circulating in Japan during 2007-2008 belonged to the new variant GII/4 2006b genetic cluster. It was demonstrated that the IC kit evaluated in this study could detect these new variant NoV strains, which emerged recently in Japan. Therefore, it is suggested that this NoV IC kit could be used as an alternative method for the screening of NoV in fecal specimens, especially during the season of acute gastroenteritis outbreak.
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AKASE S, UCHITANI Y, SOHMURA Y, TATSUTA K, SADAMASU K, ADACHI Y. Application of Real Time PCR for Diagnosis of Swine Dysentery. J Vet Med Sci 2009; 71:359-62. [DOI: 10.1292/jvms.71.359] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Satoru AKASE
- Health and Safety Division, Bureau of Social Welfare and Public Health, Tokyo Metropolitan Government
- United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology
| | - Yumi UCHITANI
- Department of Microbiology, Tokyo Metropolitan Institute of Public Health
| | - Yoshiko SOHMURA
- Johnanjima Branch Office, Animal Care and Consultation Center, Bureau of Social Welfare and Public Health, Tokyo Metropolitan Government
| | - Keikichi TATSUTA
- Shibaura Meat and Sanitary Inspection Station, Bureau of Social Welfare and Public Health, Tokyo Metropolitan Government
| | - Kenji SADAMASU
- Department of Microbiology, Tokyo Metropolitan Institute of Public Health
| | - Yoshikazu ADACHI
- College of Agriculture, Ibaraki University
- United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology
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12
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Single base substitutions in the capsid region of the norovirus genome during viral shedding in cases of infection in areas where norovirus infection is endemic. J Clin Microbiol 2008; 46:3397-403. [PMID: 18685011 DOI: 10.1128/jcm.01932-07] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Norovirus (NoV) infections are the major cause of food- and waterborne nonbacterial gastroenteritis in Japan. Some individuals showed long-term excretion of the virus into feces in 29 outbreaks of acute nonbacterial gastroenteritis that occurred in Toyama Prefecture, Japan, in fiscal year 2006. In one of these cases, single base substitutions from A to G in the capsid region of the NoV genome were commonly detected in two individuals during virus shedding by direct sequencing of PCR products. The A-to-G substitution was accompanied by an N-to-S amino acid change. The population of clones that possessed A at the corresponding site was gradually replaced by those with G during the infectious course. Although other substitutions were observed in the complete open reading frame 2 sequence, they were not common in these two individuals. NoVs are capable of evolving in the gastroenteric tract.
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Pagotto F, Corneau N, Mattison K, Bidawid S. Development of a DNA microarray for the simultaneous detection and genotyping of noroviruses. J Food Prot 2008; 71:1434-41. [PMID: 18680944 DOI: 10.4315/0362-028x-71.7.1434] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Current methods for detecting and genotyping noroviruses focus on the use of reverse transcriptase (RT)-mediated PCR. A major drawback of this approach is that short target RT-PCR products do not always encompass sequences that can be compared among research laboratories, resulting in difficulties for molecular epidemiology. We describe the use of a microarray-based system for simultaneous detection and molecular characterization of noroviruses. The protocol generates a 917-bp RT-PCR product that encompasses two major regions currently used for detection and analysis of norovirus genomes. The PCR products are then hybridized to an oligonucleotide array (NoroChip) based on 50-mer features, which allows for both confirmation of reaction specificity and molecular characterization of the amplified genome. Parallel sequence analyses of amplicons revealed that our microarray data were robust in separating genogroups I and II, and further subtyping to the cluster level was possible. This approach, combining detection and characterization, overcomes the need for expensive and time-consuming sequence analysis of amplified genome targets for molecular epidemiology.
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Affiliation(s)
- Franco Pagotto
- Microbiology Research Division, Bureau of Microbial Hazards, Food Directorate, Health Products and Food Branch, Health Canada, Sir FG Banting Research Centre, P.L. 2204E, Ottawa, Ontario, Canada.
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Fukuda S, Sasaki Y, Takao S, Seno M. Recombinant norovirus implicated in gastroenteritis outbreaks in Hiroshima Prefecture, Japan. J Med Virol 2008; 80:921-8. [PMID: 18360906 DOI: 10.1002/jmv.21151] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Norovirus (NoV) is a major etiological agent of acute gastroenteritis outbreaks worldwide. A total of 314 fecal specimens collected from patients of 39 NoV gastroenteritis outbreaks in Hiroshima Prefecture, Japan, between December 2001 and April 2006 were tested for the occurrence of recombinant NoVs. Sixteen genotypes (GI/1, GI/2, GI/4, GI/7, GI/8, GI/11, GI/14, GII/2, GII/3, GII/4, GII/5, GII/6, GII/8, GII/12, GII/14, and GII/untypeable) were detected in the 39 outbreaks based on capsid sequences and GII/4 was predominant recently. Twelve strains detected in 11 (28.2%) of the 39 outbreaks were suspected to be recombinants by using Simplot and Recco analyses and five recombinant genotypes, GII/4-GII/12 (five strains), GIIb-GII/3 (four strains), GII/4-GII/2 (one strain), GII/4-GII/14 (one strain), and GI/2-GI/8 (one strain), were identified based on RNA-dependent RNA polymerase and capsid sequences. None of the strains genotyped as GII/4 based on the capsid sequence was identified as a recombinant. The putative recombination points in the recombinant strains were placed either upstream or downstream of the open reading frame (ORF) 1 and ORF2 overlap. The present study indicates the following: (a) recombination among ORFs is common in nature, (b) the involvement of recombinant NoVs in gastroenteritis outbreaks is extensive even in a local area such as Hiroshima Prefecture, Japan, and (c) the conserved region (ORF1 and ORF2 overlap) has a meaningful function against the recombination event.
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Affiliation(s)
- Shinji Fukuda
- Center for Public Health and Environment, Hiroshima Prefectural Technology Research Institute, Hiroshima, Japan.
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15
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Evaluation of immunochromatography and commercial enzyme-linked immunosorbent assay for rapid detection of norovirus antigen in stool samples. J Virol Methods 2008; 147:360-3. [DOI: 10.1016/j.jviromet.2007.09.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2007] [Revised: 09/11/2007] [Accepted: 09/13/2007] [Indexed: 11/17/2022]
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Abstract
RNA recombination is a significant driving force in viral evolution. Increased awareness of recombination within the genus Norovirus of the family Calicivirus has led to a rise in the identification of norovirus (NoV) recombinants and they are now reported at high frequency. Currently, there is no classification system for recombinant NoVs and a widely accepted recombinant genotyping system is still needed. Consequently, there is duplication in reporting of novel recombinants. This has led to difficulties in defining the number and types of recombinants in circulation. In this study, 120 NoV nucleotide sequences were compiled from the current GenBank database and published literature. NoV recombinants and their recombination breakpoints were identified using three methods: phylogenetic analysis, SimPlot analysis and the maximum chi2 method. A total of 20 NoV recombinant types were identified in circulation worldwide. The recombination point is the ORF1/2 overlap in all isolates except one, which demonstrated a double recombination event within the polymerase region.
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Affiliation(s)
- Rowena A Bull
- School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney 2052, Australia
| | - Mark M Tanaka
- School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney 2052, Australia
| | - Peter A White
- School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney 2052, Australia
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Nguyen TA, Khamrin P, Takanashi S, Le Hoang P, Pham LD, Hoang KT, Satou K, Masuoka Y, Okitsu S, Ushijima H. Evaluation of immunochromatography tests for detection of rotavirus and norovirus among Vietnamese children with acute gastroenteritis and the emergence of a novel norovirus GII.4 variant. J Trop Pediatr 2007; 53:264-9. [PMID: 17496324 DOI: 10.1093/tropej/fmm021] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
A prospective study was conducted to evaluate two immunochromatography (ICG) tests for detection of group A rotavirus and norovirus GII, the commercial Dipstick 'Eiken' Rota kit (SA Scientific, USA) and the NV IC-1 stick (Immuno-Probe, Japan). Polymerase chain reaction (PCR) with specific primer pairs (Beg9 and VP7-1', for group A rotavirus; COG2F and G2SKR, for norovirus GII) was used as the reference method. The results of ICG tests were compared with those of reference method. The sensitivity, specificity and agreement between ICG tests and PCR were 87.8%, 93.3% and 89.4%, respectively, for rotavirus ICG test; and 73.7%, 100% and 95.2%, respectively, for norovirus ICG test. The immunochromatography assay for norovirus used in this study could detect not only common noroviruses, but also a novel norovirus GII.4 variant, which emerged in Ho Chi Minh City in 2006. Immunochromatography tests are easy, rapid and useful assays for detection of rotavirus and norovirus among pediatric patients with acute gastroenteritis in Vietnam.
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Affiliation(s)
- Tuan Anh Nguyen
- Department of Developmental Medical Sciences, Institute of International Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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