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Zhang P, Hao C, Di X, Chuizhao X, Jinsong L, Guisen Z, Hui L, Zhaojun D. Global prevalence of norovirus gastroenteritis after emergence of the GII.4 Sydney 2012 variant: a systematic review and meta-analysis. Front Public Health 2024; 12:1373322. [PMID: 38993708 PMCID: PMC11236571 DOI: 10.3389/fpubh.2024.1373322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Accepted: 05/30/2024] [Indexed: 07/13/2024] Open
Abstract
Introduction Norovirus is widely recognized as a leading cause of both sporadic cases and outbreaks of acute gastroenteritis (AGE) across all age groups. The GII.4 Sydney 2012 variant has consistently prevailed since 2012, distinguishing itself from other variants that typically circulate for a period of 2-4 years. Objective This review aims to systematically summarize the prevalence of norovirus gastroenteritis following emergence of the GII.4 Sydney 2012 variant. Methods Data were collected from PubMed, Embase, Web of Science, and Cochrane databases spanning the period between January 2012 and August 2022. A meta-analysis was conducted to investigate the global prevalence and distribution patterns of norovirus gastroenteritis from 2012 to 2022. Results The global pooled prevalence of norovirus gastroenteritis was determined to be 19.04% (16.66-21.42%) based on a comprehensive analysis of 70 studies, which included a total of 85,798 sporadic cases with acute gastroenteritis and identified 15,089 positive cases for norovirus. The prevalence rate is higher in winter than other seasons, and there are great differences among countries and age groups. The pooled attack rate of norovirus infection is estimated to be 36.89% (95% CI, 36.24-37.55%), based on a sample of 6,992 individuals who tested positive for norovirus out of a total population of 17,958 individuals exposed during outbreak events. Conclusion The global prevalence of norovirus gastroenteritis is always high, necessitating an increased emphasis on prevention and control strategies with vaccine development for this infectious disease, particularly among the children under 5 years old and the geriatric population (individuals over 60 years old).
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Affiliation(s)
- Pan Zhang
- College of Public Health, Gansu University of Traditional Chinese Medicine, Lanzhou, Gansu, China
- National Key Laboratory of Intelligent Tracking and Forecasting for Infection Diseases, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Cai Hao
- College of Public Health, Gansu University of Traditional Chinese Medicine, Lanzhou, Gansu, China
- National Key Laboratory of Intelligent Tracking and Forecasting for Infection Diseases, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Xie Di
- Chengdu Kanghua Biological Products Co., Ltd., Chengdu, China
| | - Xue Chuizhao
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, China
| | - Li Jinsong
- National Key Laboratory of Intelligent Tracking and Forecasting for Infection Diseases, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Zheng Guisen
- College of Public Health, Gansu University of Traditional Chinese Medicine, Lanzhou, Gansu, China
| | - Liu Hui
- Chengdu Kanghua Biological Products Co., Ltd., Chengdu, China
| | - Duan Zhaojun
- National Key Laboratory of Intelligent Tracking and Forecasting for Infection Diseases, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
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Yu JR, Xie DJ, Li JH, Koroma MM, Wang L, Wang Y, Jing DN, Xu JY, Yu JX, Du HS, Zhou FY, Liang ZY, Zhang XF, Dai YC. Serological surveillance of GI norovirus reveals persistence of blockade antibody in a Jidong community-based prospective cohort, 2014-2018. Front Cell Infect Microbiol 2023; 13:1258550. [PMID: 38188632 PMCID: PMC10766831 DOI: 10.3389/fcimb.2023.1258550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 11/29/2023] [Indexed: 01/09/2024] Open
Abstract
Introduction Herd immunity against norovirus (NoV) is poorly understood in terms of its serological properties and vaccine designs. The precise neutralizing serological features of genotype I (GI) NoV have not been studied. Methods To expand insights on vaccine design and herd immunity of NoVs, seroprevalence and seroincidence of NoV genotypes GI.2, GI.3, and GI.9 were determined using blockade antibodies based on a 5-year longitudinal serosurveillance among 449 residents in Jidong community. Results Correlation between human histo-blood group antigens (HBGAs) and GI NoV, and dynamic and persistency of antibodies were also analyzed. Seroprevalence of GI.2, GI.3, and GI.9 NoV were 15.1%-18.0%, 35.0%-38.8%, and 17.6%-22.0%; seroincidences were 10.0, 21.0, and 11.0 per 100.0 person-year from 2014 to 2018, respectively. Blockade antibodies positive to GI.2 and GI.3 NoV were significantly associated with HBGA phenotypes, including blood types A, B (excluding GI.3), and O+; Lewis phenotypes Leb+/Ley+ and Lea+b+/Lex+y+; and secretors. The overall decay rate of anti-GI.2 antibody was -5.9%/year (95% CI: -7.1% to -4.8%/year), which was significantly faster than that of GI.3 [-3.6%/year (95% CI: -4.6% to -2.6%/year)] and GI.9 strains [-4.0%/year (95% CI: -4.7% to -3.3%/year)]. The duration of anti-GI.2, GI.3, and GI.9 NoV antibodies estimated by generalized linear model (GLM) was approximately 2.3, 4.2, and 4.8 years, respectively. Discussion In conclusion, enhanced community surveillance of GI NoV is needed, and even one-shot vaccine may provide coast-efficient health benefits against GI NoV infection.
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Affiliation(s)
- Jing-Rong Yu
- Department of Epidemiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
- Department of Public Health, Shenzhen Qianhai Shekou Free Trade Zone Hospital, Shenzhen, China
| | - Dong-Jie Xie
- The Fifth Affiliated Hospital, Southern Medical University, Guangzhou, China
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Jia-Heng Li
- Department of Epidemiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Mark Momoh Koroma
- Department of Epidemiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Lu Wang
- Department of Epidemiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Yu Wang
- Department of Epidemiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Duo-Na Jing
- Department of Epidemiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Jia-Yi Xu
- Department of Epidemiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Jun-Xuan Yu
- Department of Epidemiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Hui-Sha Du
- Department of Epidemiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Fei-Yuan Zhou
- Department of Epidemiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Zhi-Yan Liang
- Department of Epidemiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
| | - Xu-Fu Zhang
- The Fifth Affiliated Hospital, Southern Medical University, Guangzhou, China
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Ying-Chun Dai
- Department of Epidemiology, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou, China
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Farahmand M, Moghoofei M, Dorost A, Shoja Z, Ghorbani S, Kiani SJ, Khales P, Esteghamati A, Sayyahfar S, Jafarzadeh M, Minaeian S, Khanaliha K, Naghdalipour M, Tavakoli A. Global prevalence and genotype distribution of norovirus infection in children with gastroenteritis: A meta-analysis on 6 years of research from 2015 to 2020. Rev Med Virol 2021; 32:e2237. [PMID: 33793023 DOI: 10.1002/rmv.2237] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/10/2021] [Accepted: 03/15/2021] [Indexed: 12/12/2022]
Abstract
In the post rotavirus vaccine era, norovirus (NoV) plays an increasingly important role in epidemic and sporadic gastroenteritis among children. This study was designed to provide an updated meta-analytic review of the prevalence of NoV among paediatric patients with gastroenteritis and to clarify the relationship between NoV infection and gastroenteritis. Systematic searches of the literature for potentially relevant studies were carried out from 1 January 2015 to 29 May 2020. The inverse variance method was chosen for weighting of the studies, and the random-effects model was used to analyse data. To determine the association between NoV infection and gastroenteritis in children, pooled odds ratio (OR) and its 95% confidence interval (CI) were computed for case-control studies. The pooled prevalence of NoV infection among 12,0531 children with gastroenteritis from 45 countries across the world was 17.7% (95% CI: 16.3%-19.2%). There were 28 studies with a case-control design, and the pooled prevalence of NoV infection among 11,954 control subjects was 6.7% (95% CI: 5.1%-8.8%). The pooled OR of the association of NoV infection and gastroenteritis was 2.7 (95% CI: 2.2-3.4). The most common NoV genotypes were GII.4 (59.3%) and GII.3 (14.9%). The highest frequency of NoV was found in the age group below 1 year. Our findings indicated a substantial burden of gastroenteritis caused by NoV globally, with GII.4 and GII.3 the major genotypes responsible for the majority of NoV-associated gastroenteritis cases among children. Younger age and male sex can be considered risk factors for NoV-associated gastroenteritis among children.
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Affiliation(s)
- Mohammad Farahmand
- Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohsen Moghoofei
- Department of Microbiology, Faculty of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Abolfazl Dorost
- Department of Health Economics and Management, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Saied Ghorbani
- Department of Medical Virology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Seyed Jalal Kiani
- Department of Medical Virology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Pegah Khales
- Department of Medical Virology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.,Student Research Committee, Iran University of Medical Sciences, Tehran, Iran
| | - Abdoulreza Esteghamati
- Research Center of Pediatric Infectious Diseases, Institute of Immunology and Infectious Diseases, Iran University of Medical Sciences, Tehran, Iran
| | - Shirin Sayyahfar
- Research Center of Pediatric Infectious Diseases, Institute of Immunology and Infectious Diseases, Iran University of Medical Sciences, Tehran, Iran
| | - Mehrzad Jafarzadeh
- Institute of Endocrinology and Metabolism Research and Training Center, Iran University of Medical Sciences, Tehran, Iran
| | - Sara Minaeian
- Antimicrobial Resistance Research Center, Institute of Immunology and Infectious Diseases, Iran University of Medical Sciences, Tehran, Iran
| | - Khadijeh Khanaliha
- Research Center of Pediatric Infectious Diseases, Institute of Immunology and Infectious Diseases, Iran University of Medical Sciences, Tehran, Iran
| | - Mehri Naghdalipour
- Research Center of Pediatric Infectious Diseases, Institute of Immunology and Infectious Diseases, Iran University of Medical Sciences, Tehran, Iran
| | - Ahmad Tavakoli
- Department of Medical Virology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.,Research Center of Pediatric Infectious Diseases, Institute of Immunology and Infectious Diseases, Iran University of Medical Sciences, Tehran, Iran
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4
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Xie D, Chen J, Yu J, Pei F, Koroma MM, Wang L, Qiu M, Hou Y, Yu D, Zhang XF, Dai YC. Characterization of Antigenic Relatedness Among GI Norovirus Genotypes Using Serum Samples From Norovirus-Infected Patients and Mouse Sera. Front Microbiol 2020; 11:607723. [PMID: 33363528 PMCID: PMC7752868 DOI: 10.3389/fmicb.2020.607723] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 11/11/2020] [Indexed: 12/03/2022] Open
Abstract
Characterizing diversity and the antigenic relatedness of norovirus remains a primary focus in understanding its biological properties and vaccine designs. The precise antigenic and serological features of GI genotypes have not been studied. The study represented an investigation on a gastroenteritis outbreak related to GI.3 norovirus and the three most detected GI genotypes, GI.2 (belonging to immunotype B), GI.3 and GI.9 (belonging to immunotype C), were selected to characterize their phylogenetic relationship, HBGA binding profiles and antigenic relatedness within (intra-immunotype), and between (inter-immunotypes) genotypes using mouse sera and patient’s serum samples from the GI.3 related outbreak. Wide HBGA binding profiles and evolution of binding affinity were observed in the three GI genotypes studied. A low specific blockade antibody to GI.3 in the population generated the pool of susceptible individuals and supported virus spread in the outbreak. We found strong blockade immune response in homologous strains, moderate intra-immunotype blockade but weak inter-immunotypes blockade in humans following GI.3 norovirus infections. These findings further support the immunotypes grouping and will be valuable for optimizing the design of norovirus vaccine.
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Affiliation(s)
- Dongjie Xie
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Junrui Chen
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Jingrong Yu
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Fuyu Pei
- Department of Pediatrics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Mark Momoh Koroma
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Lu Wang
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Mengsi Qiu
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Yuzhen Hou
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Dexian Yu
- Guangzhou Military Command Center for Disease Control and Prevention, Guangzhou, China
| | - Xu-Fu Zhang
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Ying-Chun Dai
- Guangdong Provincial Key Laboratory of Tropical Disease Research, Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
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Bhavanam S, Freedman SB, Lee BE, Zhuo R, Qiu Y, Chui L, Xie J, Ali S, Vanderkooi OG, Pang XL. Differences in Illness Severity among Circulating Norovirus Genotypes in a Large Pediatric Cohort with Acute Gastroenteritis. Microorganisms 2020; 8:E1873. [PMID: 33256234 PMCID: PMC7760397 DOI: 10.3390/microorganisms8121873] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/20/2020] [Accepted: 11/23/2020] [Indexed: 12/12/2022] Open
Abstract
Norovirus is a major pathogen identified in children with acute gastroenteritis (AGE), little is known about the strain's diversity and their clinical severity. Stool and/or rectal swabs were collected from children ≤18 years of age recruited at emergency departments (ED), and a provincial nursing advice phone line due to AGE symptoms in the province of Alberta, Canada between December 2014 and August 2018. Specimens were tested using a reverse transcription real time PCR and genotyped by Sanger sequencing. The Modified Vesikari Scale score (MVS) was used to evaluate the disease severity. The objectives are to identify the Genogroup and Genotype distribution and to compare illness severity between the GI and GII genogroups and to complete further analyses comparing the GII genotypes identified. GII.4 was the genotype most commonly identified. Children with GII.4 had higher MVS scores (12.0 (10.0, 14.0; p = 0.002)) and more prolonged diarrheal (5 days (3.0, 7.8)) and vomiting (3.2 days (1.7, 5.3; p < 0.001)) durations compared to other non GII.4 strains. The predominant strain varied by year with GII.4 Sydney[P31] predominant in 2014/15, GII.4 Sydney[P16] in 2015/16 and 2017/18, and GII.3[P12] in 2016/17. Genogroup II norovirus strains predominated in children with AGE with variance between years; clinical severity associated with different strains varied with episodes being most severe among GII.4 infected children.
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Affiliation(s)
- Sudha Bhavanam
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB T6G 2R3, Canada; (S.B.); (R.Z.); (Y.Q.); (L.C.)
| | - Stephen B. Freedman
- Divisions of Pediatric Emergency Medicine and Gastroenterology, Departments of Pediatrics and Emergency Medicine, Alberta Children’s Hospital, Alberta Children’s Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB T3B 6A8, Canada;
| | - Bonita E. Lee
- Department of Pediatrics, Faculty of Medicine & Dentistry, Women and Children’s Health Research Institute, Stollery Children’s Hospital, University of Alberta, Edmonton, AB T6G 2R3, Canada; (B.E.L.); (S.A.)
| | - Ran Zhuo
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB T6G 2R3, Canada; (S.B.); (R.Z.); (Y.Q.); (L.C.)
| | - Yuanyuan Qiu
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB T6G 2R3, Canada; (S.B.); (R.Z.); (Y.Q.); (L.C.)
| | - Linda Chui
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB T6G 2R3, Canada; (S.B.); (R.Z.); (Y.Q.); (L.C.)
- Public Health Laboratories (ProvLab), Alberta Precision Laboratories (APL), Edmonton, AB T6G 2J2, Canada
| | - Jianling Xie
- Departments of Pediatrics, Cumming School of Medicine, University of Calgary, Calgary, AB T3B 6A8, Canada;
| | - Samina Ali
- Department of Pediatrics, Faculty of Medicine & Dentistry, Women and Children’s Health Research Institute, Stollery Children’s Hospital, University of Alberta, Edmonton, AB T6G 2R3, Canada; (B.E.L.); (S.A.)
| | - Otto G. Vanderkooi
- Departments of Pediatrics, Microbiology, Immunology and Infectious Diseases, Pathology & Laboratory Medicine and Community Health Sciences, Alberta Children’s Hospital, Alberta Children’s Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB T3B 6A8, Canada;
| | - Xiaoli L. Pang
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB T6G 2R3, Canada; (S.B.); (R.Z.); (Y.Q.); (L.C.)
- Public Health Laboratories (ProvLab), Alberta Precision Laboratories (APL), Edmonton, AB T6G 2J2, Canada
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Pabbaraju K, Wong AA, Tipples GA, Pang XL. Emergence of a Novel Recombinant Norovirus GII.P16-GII.12 Strain Causing Gastroenteritis, Alberta, Canada. Emerg Infect Dis 2019; 25:1556-1559. [PMID: 31310222 PMCID: PMC6649330 DOI: 10.3201/eid2508.190059] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
We identified a novel recombinant GII.P16-GII.12 norovirus associated with epidemic and endemic gastroenteritis during March 1, 2018–February 12, 2019, in Alberta, Canada. GII.12 viruses have not been detected in Alberta since 2000. Comparing the full genome of this strain to previously published sequences revealed this virus to be a novel recombinant strain.
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Population Genomics of GII.4 Noroviruses Reveal Complex Diversification and New Antigenic Sites Involved in the Emergence of Pandemic Strains. mBio 2019; 10:mBio.02202-19. [PMID: 31551337 PMCID: PMC6759766 DOI: 10.1128/mbio.02202-19] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Noroviruses are an important cause of viral gastroenteritis around the world. An obstacle delaying the development of norovirus vaccines is inadequate understanding of the role of norovirus diversity in immunity. Using a population genomics approach, we identified new residues on the viral capsid protein (VP1) from GII.4 noroviruses, the predominant genotype, that appear to be involved in the emergence and antigenic topology of GII.4 variants. Careful monitoring of the substitutions in those residues involved in the diversification and emergence of new viruses could help in the early detection of future novel variants with pandemic potential. Therefore, this novel information on the antigenic diversification could facilitate GII.4 norovirus vaccine design. GII.4 noroviruses are a major cause of acute gastroenteritis. Their dominance has been partially explained by the continuous emergence of antigenically distinct variants. To gain insights into the mechanisms of viral emergence and population dynamics of GII.4 noroviruses, we performed large-scale genomics, structural, and mutational analyses of the viral capsid protein (VP1). GII.4 noroviruses exhibited a periodic replacement of predominant variants with accumulation of amino acid substitutions. Genomic analyses revealed (i) a large proportion (87%) of conserved residues; (ii) variable residues that map on the previously determined antigenic sites; and (iii) variable residues that map outside the antigenic sites. Residues in the third pattern category formed motifs on the surface of VP1, which suggested extensions of previously predicted and new uncharacterized antigenic sites. The role of two motifs (C and G) in the antigenic makeup of the GII.4 capsid protein was confirmed with monoclonal antibodies and carbohydrate blocking assays. Amino acid profiles from antigenic sites (A, C, D, E, and G) correlated with the circulation patterns of GII.4 variants, with three of them (A, C, and G) containing residues (352, 357, 368, and 378) linked with the diversifying selective pressure on the emergence of new GII.4 variants. Notably, the emergence of each variant was followed by stochastic diversification with minimal changes that did not progress toward the next variant. This report provides a methodological framework for antigenic characterization of viruses and expands our understanding of the dynamics of GII.4 noroviruses and could facilitate the design of cross-reactive vaccines.
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Kugler F, Drexler I, Protzer U, Hoffmann D, Moeini H. Generation of recombinant MVA-norovirus: a comparison study of bacterial artificial chromosome- and marker-based systems. Virol J 2019; 16:100. [PMID: 31399106 PMCID: PMC6688233 DOI: 10.1186/s12985-019-1212-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 08/05/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Recombinant Modified Vaccinia Virus Ankara has been employed as a safe and potent viral vector vaccine against infectious diseases and cancer. We generated recMVAs encoding norovirus GII.4 genotype capsid protein by using a marker-based approach and a BAC-based system. In the marker-based approach, the capsid gene together with a reporter gene was introduced into the MVA genome in DF-1 cells. Several rounds of plaque purification were carried out to get rid of the WT-MVA. In the BAC-based approach, recMVA-BAC was produced by en passant recombineering in E. coli. Subsequently, the recMVAs were rescued in DF-1 cells using a helper rabbit fibroma virus. The BAC backbone and the helper virus were eliminated by passaging in DF-1 cells. Biochemical characteristics of the recMVAs were studied. RESULTS We found the purification of the rare spontaneous recombinants time-consuming in the marker-based system. In contrast, the BAC-based system rapidly inserted the gene of interest in E. coli by en passant recombineering before virion production in DF-1 cells. The elimination of the reporter gene was found to be faster and more efficient in the BAC-based approach. With Western blotting and electron microscopy, we could prove successful capsid protein expression and proper virus-assembly, respectively. The MVA-BAC produced higher recombinant virus titers and infected DF-1 cells more efficiently. CONCLUSIONS Comparing both methods, we conclude that, in contrast to the tedious and time-consuming traditional method, the MVA-BAC system allows us to quickly generate high titer recMVAs.
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Affiliation(s)
- Franziska Kugler
- Institute of Virology, Faculty of Medicine, Technische Universität München, Munich, Germany
| | - Ingo Drexler
- Institute for Virology, Universitätklinikum Düsseldorf, Heinrich Heine Universität, Düsseldorf, Germany
| | - Ulrike Protzer
- Institute of Virology, Faculty of Medicine, Technische Universität München, Munich, Germany
| | - Dieter Hoffmann
- Institute of Virology, Faculty of Medicine, Technische Universität München, Munich, Germany.
| | - Hassan Moeini
- Institute of Virology, Faculty of Medicine, Technische Universität München, Munich, Germany.
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Mathew S, Alansari K, K Smatti M, Zaraket H, Al Thani AA, Yassine HM. Epidemiological, Molecular, and Clinical Features of Norovirus Infections among Pediatric Patients in Qatar. Viruses 2019; 11:E400. [PMID: 31035642 PMCID: PMC6563317 DOI: 10.3390/v11050400] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 04/26/2019] [Accepted: 04/27/2019] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Norovirus (NoV) is recognized as the second most important etiological agent leading to acute gastroenteritis globally. In order to determine the burden and characteristics of NoV infections in children in Qatar, profiling of circulating genotypes and their correlation with demographics and clinical manifestations were evaluated. METHODS A total of 177 NoV-positive fecal samples were collected from children suffering from acute gastroenteritis (AGE) during two-year period between June 2016 and June 2018. The age of the subjects ranged between 3 months and 12 years (median of 15 months). Genotyping was performed by amplifying and sequencing parts of viral VP1 and RNA-dependent RNA polymerase (RdRp) regions. Phylogenetic analysis and evolutionary relationships were performed using MEGA7.0. Fisher's exact test was used to run statistical analysis for the clinical and demographical characteristics of circulating strains. RESULTS Overall, NoV infections were relatively higher in males than females with a ratio of 1.3:1 (p = 0.0073). Most of the NoV infections were reported in children between 1 and 3 years old (49.7%), followed by those <1 and >3 years of age (41.2% and 9.1%, respectively). NoV infections occurred throughout the year, with a noticeable increase in summer (36.6%) and drop in winter (25.4%). Nearly all (98.8%) NoV-infected children were positive for genogroup II (GII) compared to only two samples (1.2%) being positive for genogroup I (GI): GI.3 and GI.4. NoV genotype GII.4 (62.2%), GII.2 (15.8%), and GII.3 (13.5%) were predominant in our study. The detected strains shared >98% sequence homology with emerging recombinant strain of GII.P16-GII.4/RUS/Novosibirsk/2017 (MG892929), GII.P16-GII.4 Sydney/2012 (KY887601), GII.4 Sydney/2012, recombinant GII.P4 New Orleans /2009/GII.4 Sydney 2012 (MG585810.1), and the emerging strain GII.P16-GII.2 CHN/2017 (MH321823). Severe clinical illness (vesikari score >10) was reported in children infected with genotypes sharing homology with the above emerging strains. While GII.4 was reported in all age groups, NoV GII.3 infections were higher in children <1 year of age. Both genogroups (GII.4 and GII.3) in addition to GII.2 reported higher incidence in Qatari subjects compared to other nationalities (p = 0.034). CONCLUSION This is the first report about NoV molecular epidemiology in Qatar. The most detected NoV strain was genogroup GII, which is the dominant genotype in the Middle East region. Further, we report GII.4, GII.2, and GII.3 as the most predominant NoV genotypes in our study. Moreover, disease severity scores were higher among children genotyped with genogroup GI (GI.4) and genogroup GII (GII.4, GII.2, GII.3, GII.6, and GII.7).
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Affiliation(s)
- Shilu Mathew
- Biomedical Research Center, Qatar University, Doha 2713, Qatar.
| | - Khalid Alansari
- Pediatric Emergency Center, Hamad Medical Corporation, Doha 3050, Qatar.
| | - Maria K Smatti
- Biomedical Research Center, Qatar University, Doha 2713, Qatar.
| | - Hassan Zaraket
- Department of Experimental Pathology, Microbiology, and Immunology, Faculty of Medicine, American University of Beirut, Beirut 1107 2020, Lebanon.
| | | | - Hadi M Yassine
- Biomedical Research Center, Qatar University, Doha 2713, Qatar.
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10
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Pang X, Qiu Y, Gao T, Zurawell R, Neumann NF, Craik S, Lee BE. Prevalence, levels and seasonal variations of human enteric viruses in six major rivers in Alberta, Canada. WATER RESEARCH 2019; 153:349-356. [PMID: 30743085 DOI: 10.1016/j.watres.2019.01.034] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 12/21/2018] [Accepted: 01/12/2019] [Indexed: 06/09/2023]
Abstract
The prevalence and seasonal variation of 7 viruses in 6 major rivers in Alberta were assessed using a combination of qPCR, cell culture and integrated cell culture with qPCR (ICC-qPCR). Water samples were collected monthly from rivers at different sites upstream and downstream of major urban centers. Seven viruses including rotavirus, adenovirus, astrovirus, norovirus, sapovirus, JC virus and enterovirus, were detected in at least one of the water samples at each site using qPCR. Rotavirus was most common with concentration ranging from 2.3 to 4.5 log10 genomic equivalent (GE) copies/L. Norovirus, sapovirus, astrovirus, adenoviruses and JC virus peaked during the winter (November to March). Viruses were most prevalent at the Bow River sampling site downstream of the City of Calgary, followed by the North Saskatchewan River site downstream of the City of Edmonton and the Red Deer River site downstream of the City of Red Deer. The detection rates and quantity of viruses had significant difference in the sampling sites between upstream and downstream of major urban centers (p < 0.001). 14% of the samples tested positive using viral culture indicating the presence of infectious viruses in river. Sequencing analysis identified human rotavirus in 75% of the samples collected from downstream versus 37% of the samples collected from upstream sites (p < 0.02). Multivariate binary regression showed that human activity in watersheds is a significant determinant of viruses in Alberta's Rivers. The discharge from wastewater treatment plants may be the possible sources of viral contamination. Seasonal coincidence of acute viral gastroenteritis outbreaks and monthly peak occurrence of enteric viruses in river water implies potential impact of waterborne viruses on human health.
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Affiliation(s)
- Xiaoli Pang
- Department of Laboratory Medicine and Pathology, University of Alberta, 116st & 85 Ave, Edmonton, AB, T6G 2R3, Canada; Provincial Laboratory for Public Health, 8440-112st, Edmonton, AB, T6G 2J2, Canada.
| | - Yuanyuan Qiu
- Department of Laboratory Medicine and Pathology, University of Alberta, 116st & 85 Ave, Edmonton, AB, T6G 2R3, Canada
| | - Tiejun Gao
- Department of Laboratory Medicine and Pathology, University of Alberta, 116st & 85 Ave, Edmonton, AB, T6G 2R3, Canada
| | - Ron Zurawell
- Environmental Monitoring and Science Division, Alberta Environment and Parks, Edmonton, AB, T5J 5C6, Canada
| | - Norman F Neumann
- School of Public Health, University of Alberta, 1405-87 Ave, Edmonton, AB, T6G 1C9, Canada
| | - Stephen Craik
- EPCOR Water, 9469 Rossdale Rd NW, Edmonton, AB, T5K 2E9, Canada
| | - Bonita E Lee
- Department of Paediatrics, University of Alberta, 1405-87 Ave, Edmonton, AB, T6G 1C9, Canada
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11
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Hasing ME, Lee BE, Qiu Y, Xia M, Pabbaraju K, Wong A, Tipples G, Jiang X, Pang XL. Changes in norovirus genotype diversity in gastroenteritis outbreaks in Alberta, Canada: 2012-2018. BMC Infect Dis 2019; 19:177. [PMID: 30782126 PMCID: PMC6381812 DOI: 10.1186/s12879-019-3792-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 02/07/2019] [Indexed: 11/10/2022] Open
Abstract
Background The emergence of norovirus genotype GII.4 variants has been associated with gastroenteritis pandemics worldwide, prompting molecular surveillance for early detection of novel strains. In this study, we aimed to analyze the outbreak activity of norovirus and characterize the norovirus strains circulating in Alberta between July 2012 and February 2018. Methods Stool samples from gastroenteritis outbreaks in Alberta were tested for norovirus at the Provincial Laboratory for Public Health using a multiplex real time-RT PCR assay. The ORF1 and ORF2-genotypes of norovirus positive samples were assigned based on phylogenetic analyses of partial polymerase and capsid sequences, respectively. Results A total of 530 norovirus outbreaks were identified. During July 2012 and June 2017 there was a gradual decrease in the annual number of GII.4 outbreaks, however, outbreak numbers increased from June 2017–February 2018. Four novel strains emerged: GII.17 Kawasaki in July 2014–June 2015, GII.P16/GII.4 Sydney in July 2015–June 2016, GII.P16/GII.2 and GII.P4 New Orleans/GII.4 Sydney in July 2016–June 2017. GII.Pe/GII.4 Sydney was the single predominant strain responsible for the majority (over 50%) of all norovirus outbreaks up to June 2015. Between June 2017 and February 2018, GII.P16/GII.4 Sydney was the leading strain causing 63% of all norovirus outbreaks. Conclusions GII.4 stands as the predominant capsid genotype causing a large majority of the norovirus outbreaks in early 2018. An increase in genotype diversity was observed in the last years, characterized by a high circulation of non-GII.4 strains and GII.4 recombinants. Electronic supplementary material The online version of this article (10.1186/s12879-019-3792-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Maria E Hasing
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB, Canada
| | - Bonita E Lee
- Department of Paediatrics, University of Alberta, Edmonton, AB, Canada
| | - Yuanyuan Qiu
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB, Canada
| | - Ming Xia
- Division of Infectious Diseases, Cincinnati Children's Hospital Medical Centre, Cincinnati, OH, USA
| | - Kanti Pabbaraju
- Provincial Laboratory for Public Health (Microbiology), University of Alberta Hospital, WMC 2B4.58, 8440-112 Street, Edmonton, Alberta, T6G 2J2, Canada
| | - Anita Wong
- Provincial Laboratory for Public Health (Microbiology), University of Alberta Hospital, WMC 2B4.58, 8440-112 Street, Edmonton, Alberta, T6G 2J2, Canada
| | - Graham Tipples
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.,Provincial Laboratory for Public Health (Microbiology), University of Alberta Hospital, WMC 2B4.58, 8440-112 Street, Edmonton, Alberta, T6G 2J2, Canada
| | - Xi Jiang
- Division of Infectious Diseases, Cincinnati Children's Hospital Medical Centre, Cincinnati, OH, USA
| | - Xiaoli L Pang
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB, Canada. .,Provincial Laboratory for Public Health (Microbiology), University of Alberta Hospital, WMC 2B4.58, 8440-112 Street, Edmonton, Alberta, T6G 2J2, Canada.
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12
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Qiu Y, Li Q, Lee BE, Ruecker NJ, Neumann NF, Ashbolt NJ, Pang X. UV inactivation of human infectious viruses at two full-scale wastewater treatment plants in Canada. WATER RESEARCH 2018; 147:73-81. [PMID: 30300783 DOI: 10.1016/j.watres.2018.09.057] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 09/27/2018] [Accepted: 09/30/2018] [Indexed: 05/19/2023]
Abstract
Ultraviolet (UV) disinfection is widely used to inactivate microorganisms prior to release of treated municipal wastewater. However, limited data are available for in situ inactivation of infectious enteric viruses by UV treatment at full-scale. In this study, a total of 51 pre-UV and 50 post-UV samples were collected over a two-year period from two wastewater treatment plants (WWTPs) and analyzed for noroviruses, rotavirus, reovirus, sapovirus, astrovirus, enteroviruses, adenoviruses and JC virus. Both pre-UV and post-UV samples had relatively high concentrations of these viruses determined by qPCR. Infectious viruses were also observed in 98% of pre-UV samples and 76% of post-UV samples by cell culture, using either cytopathic effect (CPE) or integrated cell culture with qPCR (ICC-qPCR). Reovirus was the most common virus detected by ICC-qPCR, present in 92% of pre-UV and 48% of post-UV samples. Infectious enterovirus and adenovirus were detected by ICC-qPCR in 33% and 31% of pre-UV samples, 14% and 20% of post-UV samples, respectively. Mean log10 reduction estimates for infectious reovirus was 1.2 and 1.8 log for the two WWTPs as assessed by ICC-qPCR, which was similar to the reduction of total infectious viruses (1.5 and 1.7 log) as assessed by CPE in cells culture. Overall, quantification of infectious reovirus appears to provide a useful index of enteric virus inactivation during wastewater treatment at full-scale. To our knowledge, this is the first comprehensive study to assess UV inactivation of human enteric viruses at full-scale in WWTPs using both molecular and cell culture techniques, providing important information for quantitative microbial risk assessment of UV inactivation of human viruses in municipal wastewater.
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Affiliation(s)
- Yuanyuan Qiu
- Department of Laboratory Medicine and Pathology, University of Alberta, 116st & 85 Ave, Edmonton, AB, T6G. 2R3, Canada
| | - Qiaozhi Li
- School of Public Health, University of Alberta, 11405-87Ave, Edmonton, AB, T6G 1C9, Canada
| | - Bonita E Lee
- Department of Pediatrics, University of Alberta, 11405-87Ave, Edmonton, AB, T6G 1C9, Canada
| | - Norma J Ruecker
- City of Calgary, Water Resources, 625, 25 Avenue SE, Calgary, AB, T2G 4K8, Canada
| | - Norman F Neumann
- School of Public Health, University of Alberta, 11405-87Ave, Edmonton, AB, T6G 1C9, Canada
| | - Nicholas J Ashbolt
- School of Public Health, University of Alberta, 11405-87Ave, Edmonton, AB, T6G 1C9, Canada; Provincial Laboratory for Public Health, 8440-112st, Edmonton, AB, T6G 2J2, Canada
| | - Xiaoli Pang
- Department of Laboratory Medicine and Pathology, University of Alberta, 116st & 85 Ave, Edmonton, AB, T6G. 2R3, Canada; Provincial Laboratory for Public Health, 8440-112st, Edmonton, AB, T6G 2J2, Canada.
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13
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Rivière M, Baroux N, Bousquet V, Ambert-Balay K, Beaudeau P, Jourdan-Da Silva N, Van Cauteren D, Bounoure F, Cahuzac F, Blanchon T, Prazuck T, Turbelin C, Hanslik T. Secular trends in incidence of acute gastroenteritis in general practice, France, 1991 to 2015. ACTA ACUST UNITED AC 2018; 22. [PMID: 29258648 PMCID: PMC5743098 DOI: 10.2807/1560-7917.es.2017.22.50.17-00121] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
We analysed 25 years of general practitioner (GP) visits for acute gastroenteritis (AG) surveillance in France, by the GP Sentinelles network. We searched for time trends of acute gastroenteritis incidence during winter periods. Data from emergency departments and drug reimbursement were additional data sources. A time-series analysis was performed using a generalised additive model for all data sources for the winter period. Virological data were incorporated and compared with the three data sources. The cumulative incidence of GP visits for winter AG exhibited an increasing trend from 1991 until 2008, when it reached 6,466 per 100,000 inhabitants. It decreased thereafter to 3,918 per 100,000 inhabitants in 2015. This decreasing trend was observed for all age groups and confirmed by the generalised additive model. For emergency department visits a decreasing trend was observed from 2004. Drug reimbursement data analyses demonstrated a decreasing trend from when data began in 2009. The incidence reported by GPs and emergency departments was lower following the emergence of norovirus GII.4 2012 (p < 0.0001). Winter AG incidences seem to follow long-term rising and decreasing trends that are important to monitor through continuous surveillance to evaluate the impact of prevention strategies, such as future immunisation against acute viral gastroenteritis.
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Affiliation(s)
- Mathieu Rivière
- Infectious disease department, CHR Orléans La Source, Orléans, France.,Sorbonne Universités, UPMC Univ Paris 06, INSERM, Institut Pierre Louis d'épidémiologie et de Santé Publique (IPLESP UMRS 1136), Paris, France
| | - Noémie Baroux
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, Institut Pierre Louis d'épidémiologie et de Santé Publique (IPLESP UMRS 1136), Paris, France
| | - Vanina Bousquet
- Santé publique France, the French national public health agency, Saint-Maurice, France
| | - Katia Ambert-Balay
- National Reference Center for Gastroenteritis Viruses, Laboratory of Virology, CHU of Dijon, Dijon, France
| | - Pascal Beaudeau
- Santé publique France, the French national public health agency, Saint-Maurice, France
| | | | - Dieter Van Cauteren
- Santé publique France, the French national public health agency, Saint-Maurice, France
| | - Frédéric Bounoure
- Pharmaceutics Laboratory (DC2N INSERM U982), Faculty of Medicine and Pharmacy, University of Rouen, Rouen, France
| | - Fanny Cahuzac
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, Institut Pierre Louis d'épidémiologie et de Santé Publique (IPLESP UMRS 1136), Paris, France
| | - Thierry Blanchon
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, Institut Pierre Louis d'épidémiologie et de Santé Publique (IPLESP UMRS 1136), Paris, France
| | - Thierry Prazuck
- Infectious disease department, CHR Orléans La Source, Orléans, France.,Sorbonne Universités, UPMC Univ Paris 06, INSERM, Institut Pierre Louis d'épidémiologie et de Santé Publique (IPLESP UMRS 1136), Paris, France
| | - Clément Turbelin
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, Institut Pierre Louis d'épidémiologie et de Santé Publique (IPLESP UMRS 1136), Paris, France
| | - Thomas Hanslik
- Université Versailles-Saint-Quentin-en-Yvelines, Versailles, France.,Sorbonne Universités, UPMC Univ Paris 06, INSERM, Institut Pierre Louis d'épidémiologie et de Santé Publique (IPLESP UMRS 1136), Paris, France
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14
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Mabasa VV, Meno KD, Taylor MB, Mans J. Environmental Surveillance for Noroviruses in Selected South African Wastewaters 2015-2016: Emergence of the Novel GII.17. FOOD AND ENVIRONMENTAL VIROLOGY 2018; 10:16-28. [PMID: 28779481 DOI: 10.1007/s12560-017-9316-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 07/29/2017] [Indexed: 06/07/2023]
Abstract
Norovirus (NoV) GII.4 is the predominant genotype associated with gastroenteritis pandemics and new strains emerge every 2-3 years. Between 2008 and 2011, environmental studies in South Africa (SA) reported NoVs in 63% of the sewage-polluted river water samples. The aim of this study was to assess whether wastewater samples could be used for routine surveillance of NoVs, including GII.4 variants. From April 2015 to March 2016, raw sewage and effluent water samples were collected monthly from five wastewater treatment plants in SA. A total of 108 samples were screened for NoV GI and GII using real-time RT-qPCR. Overall 72.2% (78/108) of samples tested positive for NoVs with 4.6% (5/108) GI, 31.5% (34/108) GII and 36.1% (39/108) GI + GII strains being detected. Norovirus concentrations ranged from 1.02 × 102 to 3.41 × 106 genome copies/litre for GI and 5.00 × 103 to 1.31 × 106 genome copies/litre for GII. Sixteen NoV genotypes (GI.2, GI.3, GI.4, GI.5, GI.6, GII.2, GII.3, GII.4, GII.7, GII.9, GII.10, GII.14, GII.16, GII.17, GII.20, and GII.21) were identified. Norovirus GII.2 and GII.17 co-dominated and the majority of GII.17 strains clustered with the novel Kawasaki 2014 variant. Sewage surveillance facilitated detection of Kawasaki 2014 in SA, which to date has not been detected with surveillance in children with gastroenteritis <5 years of age. Combined surveillance in the clinical setting and environment appears to be a valuable strategy to monitor emergence of NoV strains in countries that lack NoV outbreak surveillance.
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Affiliation(s)
- V V Mabasa
- Department of Medical Virology, Faculty of Health Sciences, University of Pretoria, Arcadia, Private Bag X323, Pretoria, 0007, South Africa
| | - K D Meno
- Department of Medical Virology, Faculty of Health Sciences, University of Pretoria, Arcadia, Private Bag X323, Pretoria, 0007, South Africa
| | - M B Taylor
- Department of Medical Virology, Faculty of Health Sciences, University of Pretoria, Arcadia, Private Bag X323, Pretoria, 0007, South Africa
| | - Janet Mans
- Department of Medical Virology, Faculty of Health Sciences, University of Pretoria, Arcadia, Private Bag X323, Pretoria, 0007, South Africa.
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15
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Neo FJX, Loh JJP, Ting P, Yeo WX, Gao CQH, Lee VJM, Tan BH, Ng CG. Outbreak of caliciviruses in the Singapore military, 2015. BMC Infect Dis 2017; 17:719. [PMID: 29137606 PMCID: PMC5686888 DOI: 10.1186/s12879-017-2821-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Accepted: 11/06/2017] [Indexed: 12/23/2022] Open
Abstract
Background From 31 August to 9 September 2015, a total of 150 military personnel at a military institution in Singapore were infected with acute gastroenteritis (AGE) with an attack rate of approximately 3%. This study aimed to determine the epidemiology of the outbreak, investigate its origins, and discuss measures to prevent future occurrences. Methods After the AGE outbreak was declared on 31 August 2015, symptom surveys, hygiene inspections, and the testing of water, food, and stool samples were initiated. We collected 86 stool samples from AGE cases and 58 samples from food-handlers during the course of the outbreak and these stool samples were tested for 8 bacterial pathogens and 2 viral pathogens (i.e., norovirus and sapovirus). Results We detected Sapovirus (SaV), group I Norovirus (NoV GI) and group II Norovirus (NoV GII) from the stool samples of AGE cases. Further sequence analyses showed that the AGE outbreak in August was caused mainly by three rarely reported calicivirus novel genotypes: NoV GI.7, NoV GII.17 and SaV GII.3. Control measures implemented focused on the escalation of personal and environmental hygiene, which included the separation of affected and unaffected soldiers, enforcement of rigorous hand-washing and hygiene, raising awareness of food and water safety, and disinfection of communal areas with bleach. Conclusions This study identified both NoV and SaV as the causative agents for an AGE outbreak at a Singapore military camp in August 2015. This study is also the first to report SaV as one of the main causative agents, highlighting the importance of caliciviruses as causative agents of AGE outbreaks in the Singapore military. As there are no commercially available vaccines against caliciviruses, strict personal hygiene and proper disinfection of environmental surfaces remain crucial to prevent calicivirus outbreak and transmission.
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Affiliation(s)
- Freddy Jun Xian Neo
- DSO National Laboratories, 27, Medical Drive, #09-01, Singapore, 117510, Singapore
| | - Jimmy Jin Phang Loh
- DSO National Laboratories, 27, Medical Drive, #09-01, Singapore, 117510, Singapore
| | - Peijun Ting
- DSO National Laboratories, 27, Medical Drive, #09-01, Singapore, 117510, Singapore
| | - Wei Xin Yeo
- HQ Medical Corps, Singapore Armed Forces, HQ Medical Corps, 701 Transit Road #04-01, Singapore, 778910, Singapore
| | - Christine Qiu Han Gao
- HQ Medical Corps, Singapore Armed Forces, HQ Medical Corps, 701 Transit Road #04-01, Singapore, 778910, Singapore
| | - Vernon Jian Ming Lee
- HQ Medical Corps, Singapore Armed Forces, HQ Medical Corps, 701 Transit Road #04-01, Singapore, 778910, Singapore
| | - Boon Huan Tan
- DSO National Laboratories, 27, Medical Drive, #09-01, Singapore, 117510, Singapore
| | - Ching Ging Ng
- DSO National Laboratories, 27, Medical Drive, #09-01, Singapore, 117510, Singapore.
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16
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Slow Clearance of Norovirus following Infection with Emerging Variants of Genotype GII.4 Strains. J Clin Microbiol 2017; 55:1533-1539. [PMID: 28275078 DOI: 10.1128/jcm.00061-17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 03/02/2017] [Indexed: 11/20/2022] Open
Abstract
The emergence of new norovirus genotype GII.4 strains is associated with widespread norovirus epidemics. Extended periods of viral shedding can contribute to the epidemic potential of norovirus. To describe the duration of viral shedding in infections with novel emerging GII.4 strains versus infections with previously circulating strains, we performed a prospective cohort study of patients hospitalized with norovirus gastroenteritis during separate winter seasons. Rectal swab samples were obtained at the time of inclusion and weekly during follow-ups. The subgenotype strain was determined from capsid sequences. The outcome was defined by the detection of virus for >14 days (slow clearance) or by the detection of negative samples within 14 days (rapid clearance). Two major epidemic GII.4 strains emerged during the study period, GII.4 New Orleans 2009, in 2010, and GII.4 Sydney 2012, in 2012. From these two seasons, sequences were available from 24 cases where the duration of shedding could be determined. The median age of the patients was 83 years and 50% were women. The majority of patients were infected with virus that clustered with the respective season's epidemic strain (n = 19), whereas 5 patients had previously circulating strains (3 were Den Haag 2006b, in 2010, and 2 were New Orleans 2009, in 2012). Among the patients infected with an epidemic strain, the proportion who shed virus for >14 days was significantly higher (16/19 [84%] versus 1/5 [20%], P = 0.01). In summary, a slow clearance of norovirus from stool was more common in infections with novel epidemic GII.4 strains. This suggests that the average duration of shedding may be longer during seasons when new GII.4 strains have emerged.
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17
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Norovirus Disease in Older Adults Living in Long-Term Care Facilities: Strategies for Management. CURRENT GERIATRICS REPORTS 2017; 6:26-33. [PMID: 29204334 DOI: 10.1007/s13670-017-0195-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Purpose of Review Noroviruses are the most common cause of gastroenteritis outbreaks in long-term care facility (LTCFs). This review summarizes the most up-to-date knowledge on norovirus infection in LTCFs with the aim of identifying potential strategies for management. Recent Findings LTCF residents are at greater risk of norovirus infection. Early identification of norovirus infection and prompt initiation of appropriate supportive therapy are required to reduce morbidity and mortality. Measures to prevent outbreaks and reduce the risk of norovirus infection in LTCFs include timely diagnosis and implementation of infection control interventions to limit virus transmission. Summary Current guidelines for prevention and control are based on generic principles of infection control. Real-time reverse transcription-quantitative polymerase chain reaction assays have been the gold standard for the rapid and sensitive detection of noroviruses. With the recent breakthroughs of human norovirus in vitro culture, doors are now opened to evaluate the efficacy of environmental disinfectants and hand hygiene options. Additionally, development of licensed vaccines against noroviruses may provide another important tool for infection prevention among high-risk individuals.
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18
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Kraut RY, Snedeker KG, Babenko O, Honish L. Influence of School Year on Seasonality of Norovirus Outbreaks in Developed Countries. THE CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY = JOURNAL CANADIEN DES MALADIES INFECTIEUSES ET DE LA MICROBIOLOGIE MEDICALE 2017; 2017:9258140. [PMID: 28167970 PMCID: PMC5266842 DOI: 10.1155/2017/9258140] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 11/24/2016] [Indexed: 11/17/2022]
Abstract
Factors affecting the seasonal distribution of norovirus outbreaks are not well understood. This study examined whether grade school settings at the start of the school year may be a factor. We searched Ovid Medline from January 2002 to June 2014 for studies that provided all reported norovirus outbreaks in a developed country by month for a minimum of three years. Historical school years were obtained from verifiable sources. The start of the norovirus seasonal outbreak peak and peak outbreak month were determined for each study and compared to the start month of school. Northern hemisphere and southern hemisphere countries had a different norovirus seasonality and different school year structures (traditional compared to year round). In the two studies that provided outbreaks by age, outbreaks among children started several months before outbreaks in the adult population. The median number of months between school start and start of the seasonal outbreak peak was two months (interquartile range [IQR] = 2.0-3.0), while the median number of months between school start and peak outbreak month was four months (IQR = 3.0-4.0). These findings suggest the possibility the school setting at the start of the school year may be a factor in the seasonality of norovirus.
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Affiliation(s)
- Roni Y. Kraut
- Department of Family Medicine, University of Alberta, Edmonton, AB, Canada T6G 2T4
| | - Kate G. Snedeker
- Department of Public Health Sciences, University of Alberta, Edmonton, AB, Canada T6G 1C9
- Surveillance and Reporting, Alberta Health Services, Edmonton, AB, Canada T2W 3N2
| | - Oksana Babenko
- Department of Family Medicine, University of Alberta, Edmonton, AB, Canada T6G 2T4
| | - Lance Honish
- Environmental Public Health, Alberta Health Services, Edmonton, AB, Canada T5J 2Y2
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19
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Viral Infections, an Overview with a Focus on Prevention of Transmission. INTERNATIONAL ENCYCLOPEDIA OF PUBLIC HEALTH 2017. [PMCID: PMC7150291 DOI: 10.1016/b978-0-12-803678-5.00514-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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20
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Kumazaki M, Usuku S. Norovirus genotype distribution in outbreaks of acute gastroenteritis among children and older people: an 8-year study. BMC Infect Dis 2016; 16:643. [PMID: 27821133 PMCID: PMC5100332 DOI: 10.1186/s12879-016-1999-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 10/29/2016] [Indexed: 02/05/2023] Open
Abstract
Background Noroviruses (NoVs) are the most frequent cause of acute gastroenteritis worldwide among people of all ages and the leading cause of gastrointestinal disease outbreaks in various settings. To clarify the differences in epidemic situations among different settings, we investigated epidemiological trends and the distribution of NoV genotypes in Yokohama, Japan. Methods Between September 2007 and August 2015, 746 outbreaks of NoV gastroenteritis were reported in kindergarten/nursery schools (K/Ns), primary schools (PSs), and nursing homes for the aged (NHs). Stool samples were collected for NoV testing, and the NoV gene was amplified and sequenced to determine the genotype. Results During the eight seasons, 248 NoV outbreaks occurred in K/Ns, 274 outbreaks in PSs, and 224 outbreaks in NHs. These outbreaks occurred throughout the year, except in August, and the number increased in November and peaked in December. The number of outbreaks that occurred from November to February comprised 76.8 % of all outbreaks. The outbreaks originated in K/Ns or PSs in every season, except for one season. Five genogroup (G)I and nine GII genotypes in K/Ns, six GI and 10 GII genotypes in PSs, and three GI and six GII genotypes in NHs were detected during the eight seasons. GII.4 was the most prevalent genotype in K/Ns and NHs. However, GII.6 was the most prevalent genotype in PSs. The epidemic genotypes in K/Ns and PSs changed by NoV season, although GII.4 was always predominant in NHs. Moreover, the distribution of genotypes was significantly different between epidemic and non-epidemic periods in each facility (p < 0.01 for all). Conclusions The epidemic situation of NoV outbreaks differs by facility, NoV season, and month. The genotype distribution is likely dependent on the facility and is significantly different between epidemic and non-epidemic periods.
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Affiliation(s)
- Makoto Kumazaki
- Microbiological Testing and Research Division, Yokohama City Institute of Public Health, Kanagawa, Japan. .,Yokohama City Institute of Public Health, 2-7-1 Tomiokahigashi, Kanazawa-ku, Yokohama, Kanagawa, 236-0051, Japan.
| | - Shuzo Usuku
- Microbiological Testing and Research Division, Yokohama City Institute of Public Health, Kanagawa, Japan.,Yokohama City Institute of Public Health, 2-7-1 Tomiokahigashi, Kanazawa-ku, Yokohama, Kanagawa, 236-0051, Japan
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21
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Ali ES, Rajapaksha H, Carr JM, Petrovsky N. Norovirus drug candidates that inhibit viral capsid attachment to human histo-blood group antigens. Antiviral Res 2016; 133:14-22. [PMID: 27421712 DOI: 10.1016/j.antiviral.2016.07.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Revised: 07/02/2016] [Accepted: 07/06/2016] [Indexed: 01/11/2023]
Abstract
Human noroviruses are the leading causative agents of epidemic and sporadic viral gastroenteritis and childhood diarrhoea worldwide. Human histo-blood group antigens (HBGA) serve as receptors for norovirus capsid protein attachment and play a critical role in infection. This makes HBGA-norovirus binding a promising target for drug development. Recently solved crystal structures of norovirus bound to HBGA have provided a structural basis for identification of potential anti-norovirus drugs and subsequently performed in silico and in vitro drug screens have identified compounds that block norovirus binding and may thereby serve as structural templates for design of therapeutic norovirus inhibitors. This review explores norovirus therapeutic options based on the strategy of blocking norovirus-HBGA binding.
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Affiliation(s)
- Eunüs S Ali
- School of Medicine, Flinders University, Adelaide, South Australia, Australia
| | - Harinda Rajapaksha
- Vaxine Pty Ltd, Flinders Medical Centre/Flinders University, Adelaide, South Australia, Australia
| | - Jillian M Carr
- Department of Microbiology & Infectious Diseases, School of Medicine, Flinders University, Adelaide, South Australia, Australia
| | - Nikolai Petrovsky
- School of Medicine, Flinders University, Adelaide, South Australia, Australia; Vaxine Pty Ltd, Flinders Medical Centre/Flinders University, Adelaide, South Australia, Australia.
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22
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Hasing ME, Hazes B, Lee BE, Preiksaitis JK, Pang XL. A next generation sequencing-based method to study the intra-host genetic diversity of norovirus in patients with acute and chronic infection. BMC Genomics 2016; 17:480. [PMID: 27363999 PMCID: PMC4929757 DOI: 10.1186/s12864-016-2831-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 06/12/2016] [Indexed: 12/12/2022] Open
Abstract
Background Immunocompromised individuals with chronic norovirus (NoV) infection and elderly patients are hypothesized to be reservoirs where NoV might accumulate mutations and evolve into pandemic strains. Next generation sequencing (NGS) methods can monitor the intra-host diversity of NoV and its evolution but low abundance of viral RNA results in sub-optimal efficiency. In this study, we: 1) established a next generation sequencing-based method for NoV using bacterial rRNA depletion as a viral RNA enrichment strategy, and 2) measured the intra-host genetic diversity of NoV in specimens of patients with acute NoV infection (n = 4) and in longitudinal specimens of an immunocompromised patient with chronic NoV infection (n = 2). Results A single Illumina MiSeq dataset resulted in near full-length genome sequences for 5 out of 6 multiplexed samples. Experimental depletion of bacterial rRNA in stool RNA provided up to 1.9 % of NoV reads. The intra-host viral population in patients with acute NoV infection was homogenous and no single nucleotide variants (SNVs) were detected. In contrast, the NoV population from the immunocompromised patient was highly diverse and accumulated SNVs over time (51 SNVs in the first sample and 122 SNVs in the second sample collected 4 months later). The percentages of SNVs causing non-synonymous mutations were 27.5 % and 20.5 % for the first and second samples, respectively. The majority of non-synonymous mutations occurred, in increasing order of frequency, in p22, the major capsid (VP1) and minor capsid (VP2) genes. Conclusions The results provide data useful for the selection and improvement of NoV RNA enrichment strategies for NGS. Whole genome analysis using next generation sequencing confirmed that the within-host population of NoV in an immunocompromised individual with chronic NoV infection was more diverse compared to that in individuals with acute infection. We also observed an accumulation of non-synonymous mutations at the minor capsid gene that has not been reported in previous studies and might have a role in NoV adaptation. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2831-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Maria E Hasing
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB, T6G 2B7, Canada
| | - Bart Hazes
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, T6G 2E1, Canada
| | - Bonita E Lee
- Department of Pediatrics, University of Alberta, Edmonton, AB, T6G 1C9, Canada
| | - Jutta K Preiksaitis
- Department of Medicine, University of Alberta, Edmonton, AB, T6G 2B7, Canada
| | - Xiaoli L Pang
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB, T6G 2B7, Canada. .,Provincial Laboratory for Public Health (ProvLab), Edmonton, AB, T6G 2 J2, Canada.
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Chi-Chung Cheng V, Fuk-Woo Chan J, FN Hung I, Yuen KY. Viral Infections, an Overview with a Focus on Prevention of Transmission. REFERENCE MODULE IN BIOMEDICAL SCIENCES 2016. [PMCID: PMC7157453 DOI: 10.1016/b978-0-12-801238-3.90174-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Kumazaki M, Usuku S. Genetic Analysis of Norovirus GII.4 Variant Strains Detected in Outbreaks of Gastroenteritis in Yokohama, Japan, from the 2006-2007 to the 2013-2014 Seasons. PLoS One 2015; 10:e0142568. [PMID: 26544040 PMCID: PMC4636242 DOI: 10.1371/journal.pone.0142568] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 10/24/2015] [Indexed: 11/18/2022] Open
Abstract
Noroviruses (NoVs) are the leading cause of acute gastroenteritis, both in sporadic cases and outbreaks. Since the 1990s, the emergence of several GII.4 variants has been reported worldwide. To investigate the epidemic status of NoV, 6,724 stool samples collected from outbreaks in Yokohama, Japan, from the 2006-2007 to 2013-2014 seasons were assessed for NoVs. We genotyped one specimen from each GII outbreak and conducted a sequence analysis of the VP1 gene for several GII.4 strains. Of the 947 NoV outbreaks during our study, GII was detected in 835, and GII.4 was the predominant genotype of GII. Five different GII.4 variants, Yerseke 2006a, Den Haag 2006b (2006b), Apeldoorn 2007, New Orleans 2009, and Sydney 2012, were detected. During this study period, the most prevalent variant of GII.4 was 2006b, and in each individual season, either 2006b or Sydney 2012 was the predominant variant. Out of the 16 detected 2006b strains, 12 had some amino acid substitutions in their blockade epitope, and these substitutions were concentrated in three residues. Two of the 2006b strains detected in the 2012-2013 season had a S368E substitution, which is consistent with the amino acid residues at same site of NSW0514 (Sydney 2012 prototype). Among the 16 detected strains of Sydney 2012, a phylogenetic analysis showed that all five strains detected in Yokohama during the 2011-2012 season clustered away from the other Sydney 2012 strains that were detected in the 2012-2013 and 2013-2014 seasons. These five strains and other Sydney 2012 strains in Yokohama had a few amino acid differences in the blockade epitopes compared with NSW0514. The amino acid substitutions observed in this study provide informative data about the evolution of a novel GII.4 variant.
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Affiliation(s)
- Makoto Kumazaki
- Microbiological Testing and Research Division, Yokohama City Institute of Public Health, Kanagawa, Japan
- * E-mail:
| | - Shuzo Usuku
- Microbiological Testing and Research Division, Yokohama City Institute of Public Health, Kanagawa, Japan
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25
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Cho HG, Park PH, Lee SG, Kim JE, Kim KA, Lee HK, Park EM, Park MK, Jung SY, Lee DY, Yoon MH, Lee JB, Paik SY. Emergence of Norovirus GII.4 variants in acute gastroenteritis outbreaks in South Korea between 2006 and 2013. J Clin Virol 2015; 72:11-5. [DOI: 10.1016/j.jcv.2015.08.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 08/17/2015] [Accepted: 08/24/2015] [Indexed: 02/07/2023]
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Huo Y, Wan X, Ling T, Wu J, Wang Z, Meng S, Shen S. Prevailing Sydney like Norovirus GII.4 VLPs induce systemic and mucosal immune responses in mice. Mol Immunol 2015; 68:367-72. [PMID: 26375574 DOI: 10.1016/j.molimm.2015.09.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 08/29/2015] [Accepted: 09/05/2015] [Indexed: 02/08/2023]
Abstract
The newly emerged Norovirus (NoV) Sydney 2012 strain has been sweeping all over the world, causing acute non-bacterial gastroenteritis in adults and children. Due to a lack of cell culture system, virus like particles (VLPs) has been assembled and used as vaccine candidates in preclinical and clinical studies. Expression of the major capsid protein of NoVs using recombinant baculovirus expression system in Sf9 cells leads to formation of VLPs that are morphologically and antigenically similar to true virions. In this study, VLPs were successfully produced using the VP1 of Sydney-2012-like strain and its immunogenicity was evaluated by different routes and its capability in inducing mucosal immune responses in the presence and absence of adjuvants in BALB/c mice. Administration of NoV VLPs in the presence of Al(OH)3 or monophosphoryl lipid A (MPL-A) led to high titers of VLP-specific IgG antibodies. Administration of VLPs orally in the presence of cholera toxin subunit B (CTB) didn't enhance mucosal immune response as less fecal IgA positive mice were observed when compared with those given VLPs only. Our study represents the first immunogenicity study of VLPs derived from current pandemic Sydney 2012 strain and which might have implications in the development of NoVs vaccine in china.
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Affiliation(s)
- Yuqi Huo
- Wuhan Institute of Biological Products Co., Ltd., Wuhan, PR China.
| | - Xin Wan
- Wuhan Institute of Biological Products Co., Ltd., Wuhan, PR China
| | - Tong Ling
- Wuhan Institute of Biological Products Co., Ltd., Wuhan, PR China
| | - Jie Wu
- Wuhan Institute of Biological Products Co., Ltd., Wuhan, PR China
| | - Zejun Wang
- Wuhan Institute of Biological Products Co., Ltd., Wuhan, PR China
| | - Shengli Meng
- Wuhan Institute of Biological Products Co., Ltd., Wuhan, PR China
| | - Shuo Shen
- Wuhan Institute of Biological Products Co., Ltd., Wuhan, PR China.
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27
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Pringle K, Lopman B, Vega E, Vinje J, Parashar UD, Hall AJ. Noroviruses: epidemiology, immunity and prospects for prevention. Future Microbiol 2015; 10:53-67. [PMID: 25598337 DOI: 10.2217/fmb.14.102] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
In recent years, noroviruses have become recognized as an important cause of both sporadic and epidemic acute gastroenteritis (AGE), largely due to the improved availability of broadly reactive real-time RT-PCR (TaqMan-based RT-PCR) assays. While there is substantial diversity among noroviruses, one specific genotype, GII.4, is the most common etiology in sporadic and epidemic AGE. Outbreaks of norovirus AGE most commonly occur in healthcare facilities and restaurants and result in significant morbidity and mortality and substantial healthcare costs. Norovirus vaccine development is progressing, and Phase I and II human trials have shown proof-of-principle that norovirus vaccines can reduce illness and infection.
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Affiliation(s)
- Kimberly Pringle
- Division of Viral Diseases, National Center for Immunization & Respiratory Diseases, Centers for Disease Control & Prevention, 1600 Clifton Road, Mailstop A-34, Atlanta, GA, 30333, USA
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28
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Freedman SB, Lee BE, Louie M, Pang XL, Ali S, Chuck A, Chui L, Currie GR, Dickinson J, Drews SJ, Eltorki M, Graham T, Jiang X, Johnson DW, Kellner J, Lavoie M, MacDonald J, MacDonald S, Svenson LW, Talbot J, Tarr P, Tellier R, Vanderkooi OG. Alberta Provincial Pediatric EnTeric Infection TEam (APPETITE): epidemiology, emerging organisms, and economics. BMC Pediatr 2015; 15:89. [PMID: 26226953 PMCID: PMC4521468 DOI: 10.1186/s12887-015-0407-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 07/15/2015] [Indexed: 01/05/2023] Open
Abstract
Background Each year in Canada there are 5 million episodes of acute gastroenteritis (AGE) with up to 70 % attributed to an unidentified pathogen. Moreover, 90 % of individuals with AGE do not seek care when ill, thus, burden of disease estimates are limited by under-diagnosing and under-reporting. Further, little is known about the pathogens causing AGE as the majority of episodes are attributed to an “unidentified” etiology. Our team has two main objectives: 1) to improve health through enhanced enteric pathogen identification; 2) to develop economic models incorporating pathogen burden and societal preferences to inform enteric vaccine decision making. Methods/Design This project involves multiple stages: 1) Molecular microbiology experts will participate in a modified Delphi process designed to define criteria to aid in interpreting positive molecular enteric pathogen test results. 2) Clinical data and specimens will be collected from children aged 0–18 years, with vomiting and/or diarrhea who seek medical care in emergency departments, primary care clinics and from those who contact a provincial medical advice line but who do not seek care. Samples to be collected will include stool, rectal swabs (N = 2), and an oral swab. Specimens will be tested employing 1) stool culture; 2) in-house multiplex (N = 5) viral polymerase chain reaction (PCR) panel; and 3) multi-target (N = 15) PCR commercially available array. All participants will have follow-up data collected 14 days later to enable calculation of a Modified Vesikari Scale score and a Burden of Disease Index. Specimens will also be collected from asymptomatic children during their well child vaccination visits to a provincial public health clinic. Following the completion of the initial phases, discrete choice experiments will be conducted to enable a better understanding of societal preferences for diagnostic testing and vaccine policy. All of the results obtained will be integrated into economic models. Discussion This study is collecting novel samples (e.g., oral swabs) from previously untested groups of children (e.g., those not seeking medical care) which are then undergoing extensive molecular testing to shed a new perspective on the epidemiology of AGE. The knowledge gained will provide the broadest understanding of the epidemiology of vomiting and diarrhea of children to date.
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Affiliation(s)
- Stephen B Freedman
- Department of Pediatrics, Sections of Pediatric Emergency Medicine and Gastroenterology, Alberta Children's Hospital, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada.
| | - Bonita E Lee
- Department of Pediatrics, Stollery Children's Hospital, University of Alberta, Edmonton, AB, Canada.
| | - Marie Louie
- Provincial Laboratory for Public Health (ProvLab, Alberta Health Services), Departments of Microbiology, Immunology & Infectious Disease and Pathology & Laboratory Medicine, University of Calgary, Calgary, AB, Canada.
| | - Xiao-Li Pang
- Department of Laboratory Medicine & Pathology, University of Alberta, Edmonton, AB, Canada.
| | - Samina Ali
- Department of Pediatrics & Emergency Medicine, University of Alberta, Faculty of Medicine & Dentistry, Women and Children's Health Research Institute, Stollery Children's Hospital, Edmonton, AB, Canada.
| | - Andy Chuck
- Institute of Health Economics, Edmonton, AB, Canada.
| | - Linda Chui
- University of Alberta, Edmonton, AB, Canada.
| | - Gillian R Currie
- Department of Pediatrics, Alberta Children's Hospital Research Institute, O'Brien Institute of Public Health, University of Calgary, Calgary, AB, Canada. .,Department of Community Health Sciences, Alberta Children's Hospital Research Institute, O'Brien Institute of Public Health, University of Calgary, Calgary, AB, Canada.
| | - James Dickinson
- Departments of Family Medicine and Community Health Sciences, University of Calgary, Calgary, AB, Canada.
| | - Steven J Drews
- Department of Laboratory Medicine & Pathology, University of Alberta, Edmonton, AB, Canada.
| | - Mohamed Eltorki
- Department of Pediatrics, Section of Pediatric Emergency Medicine, Alberta Children's Hospital, University of Calgary, Calgary, AB, Canada.
| | - Tim Graham
- Department of Emergency Medicine, University of Alberta, Edmonton, AB, Canada.
| | - Xi Jiang
- Division of Infectious Diseases, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, USA.
| | - David W Johnson
- Departments of Pediatrics and Physiology and Pharmacology, Section of Pediatric Emergency Medicine, Alberta Children's Hospital, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada.
| | - James Kellner
- Department of Pediatrics, Section of Infectious Diseases, Alberta Children's Hospital, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada.
| | - Martin Lavoie
- Alberta Health, University of Alberta, Edmonton, AB, Canada.
| | - Judy MacDonald
- Alberta Health Services, Department of Community Health Sciences, University of Calgary, Calgary, AB, Canada.
| | - Shannon MacDonald
- Department of Pediatrics, University of Calgary, Edmonton, AB, Canada. .,Faculty of Nursing, University of Alberta, Edmonton, AB, Canada.
| | | | - James Talbot
- Alberta Health, University of Alberta, Edmonton, AB, Canada.
| | - Phillip Tarr
- Division of Gastroenterology, Washington University, St. Louis, MO, USA.
| | - Raymond Tellier
- Department of Microbiology, Immunology and Infectious Disease, University of Calgary, Calgary, AB, Canada.
| | - Otto G Vanderkooi
- Department of Pediatrics, Section of Infectious Diseases, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada. .,Department of Pathology and Laboratory Medicine, Section of Microbiology, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada. .,Department of Microbiology, Immunology & Infectious Diseases, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada.
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29
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Chan MCW, Leung TF, Chung TWS, Kwok AK, Nelson EAS, Lee N, Chan PKS. Virus Genotype Distribution and Virus Burden in Children and Adults Hospitalized for Norovirus Gastroenteritis, 2012-2014, Hong Kong. Sci Rep 2015; 5:11507. [PMID: 26082165 PMCID: PMC4469980 DOI: 10.1038/srep11507] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 05/28/2015] [Indexed: 11/29/2022] Open
Abstract
We conducted a 2-year hospital-based study on norovirus gastroenteritis among children and adults between August 2012 and September 2014. A total of 1,146 norovirus cases were identified. Young children (aged ≤ 5 years) accounted for a majority (53.3%) of cases. Hospitalization incidence exhibited a U-shaped pattern with the highest rate in young children (1,475 per 100,000 person-years), followed by the elderly aged > 84 years (581 per 100,000 person-years). A subset (n = 395, 34.5%) of cases were selected for norovirus genotyping and noroviral load measurement. Non-GII.4 infections were more commonly observed in young children than in older adults (aged > 65 years) (20.5% versus 9.2%; p < 0.05). In young children, the median noroviral load of GII.4 and non-GII.4 cases was indistinguishably high (cycle threshold value, median [interquartile range]: 16.6 [15.2–19.3] versus 16.6 [14.9–21.6]; p = 0.45). Two age-specific non-GII.4 genotypes (GII.3 and GII.6) were identified among young children. These findings may have implications in norovirus vaccination strategy.
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Affiliation(s)
- Martin C W Chan
- Department of Microbiology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China
| | - Ting F Leung
- Department of Paediatrics, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China
| | - Tracy W S Chung
- Department of Microbiology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China
| | - Angela K Kwok
- Department of Microbiology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China
| | - E Anthony S Nelson
- Department of Paediatrics, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China
| | - Nelson Lee
- Department of Medicine and Therapeutics, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China
| | - Paul K S Chan
- Department of Microbiology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China
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30
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Medici MC, Tummolo F, Grazia SD, Calderaro A, Conto FD, Terio V, Chironna M, Bonura F, Pucci M, Bányai K, Martella V, Giammanco GM. Epidemiological dynamics of norovirus GII.4 variant New Orleans 2009. J Gen Virol 2015; 96:2919-2927. [PMID: 26025873 DOI: 10.1099/vir.0.000204] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Norovirus (NoV) is one of the major causes of diarrhoeal disease with epidemic, outbreak and sporadic patterns in humans of all ages worldwide. NoVs of genotype GII.4 cause nearly 80-90 % of all NoV infections in humans. Periodically, some GII.4 strains become predominant, generating major pandemic variants. Retrospective analysis of the GII.4 NoV strains detected in Italy between 2007 and 2013 indicated that the pandemic variant New Orleans 2009 emerged in Italy in the late 2009, became predominant in 2010-2011 and continued to circulate in a sporadic fashion until April 2013. Upon phylogenetic analysis based on the small diagnostic regions A and C, the late New Orleans 2009 NoVs circulating during 2011-2013 appeared to be genetically different from the early New Orleans 2009 strains that circulated in 2010. For a selection of strains, a 3.2 kb genome portion at the 3' end was sequenced. In the partial ORF1 and in the full-length ORF2 and ORF3, the 2011-2013 New Orleans NoVs comprised at least three distinct genetic subclusters. By comparison with sequences retrieved from the databases, these subclusters were also found to circulate globally, suggesting that the local circulation reflected repeated introductions of different strains, rather than local selection of novel viruses. Phylogenetic subclustering did not correlate with changes in residues located in predicted putative capsid epitopes, although several changes affected the P2 domain in epitopes A, C, D and E.
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Affiliation(s)
- Maria Cristina Medici
- Unità di Microbiologia e Virologia, Dipartimento di Medicina Clinica e Sperimentale, Università degli Studi di Parma, Parma, Italy
| | - Fabio Tummolo
- Unità di Microbiologia e Virologia, Dipartimento di Medicina Clinica e Sperimentale, Università degli Studi di Parma, Parma, Italy
| | - Simona De Grazia
- Dipartimento di Scienze per la Promozione della Salute e Materno Infantile G. D'Alessandro, Università di Palermo, Palermo, Italy
| | - Adriana Calderaro
- Unità di Microbiologia e Virologia, Dipartimento di Medicina Clinica e Sperimentale, Università degli Studi di Parma, Parma, Italy
| | - Flora De Conto
- Unità di Microbiologia e Virologia, Dipartimento di Medicina Clinica e Sperimentale, Università degli Studi di Parma, Parma, Italy
| | - Valentina Terio
- Dipartimento di Medicina Veterinaria, Università Aldo Moro di Bari, Valenzano, Italy
| | - Maria Chironna
- Dipartimento di Scienze Biomediche ed Oncologia Umana, Sezione di Igiene e Medicina Preventiva, Policlinico di Bari, Bari, Italy
| | - Floriana Bonura
- Dipartimento di Scienze per la Promozione della Salute e Materno Infantile G. D'Alessandro, Università di Palermo, Palermo, Italy
| | - Marzia Pucci
- Dipartimento di Scienze per la Promozione della Salute e Materno Infantile G. D'Alessandro, Università di Palermo, Palermo, Italy
| | - Kristián Bányai
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, Hungária krt. 21, Budapest, 1143, Hungary
| | - Vito Martella
- Dipartimento di Medicina Veterinaria, Università Aldo Moro di Bari, Valenzano, Italy
| | - Giovanni Maurizio Giammanco
- Dipartimento di Scienze per la Promozione della Salute e Materno Infantile G. D'Alessandro, Università di Palermo, Palermo, Italy
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31
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Gao Z, Li X, Yan H, Li W, Jia L, Hu L, Hu H, Liu B, Li J, Wang Q. Human calicivirus occurrence among outpatients with diarrhea in Beijing, China, between April 2011 and March 2013. J Med Virol 2015; 87:2040-7. [PMID: 25982899 DOI: 10.1002/jmv.24265] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/06/2015] [Indexed: 12/28/2022]
Abstract
Human caliciviruses (HuCVs), including noroviruses (NoVs) and sapoviruses (SaVs), are the most common cause of diarrhea in adults and the second most common cause of diarrhea in children. Between April 2011 and March 2013, 3,832 fecal specimens were collected from outpatients with diarrhea from 17 hospitals in Beijing, China, and 669 specimens (17.5%) were positive for HuCV. Of the 287 HuCV-positive specimens, 263 (91.6%) were identified to be NoV, 23 (8.0%) were identified to be SaV, and one (0.3%) was identified to be a mixed infection of NoV and SaV. Of the 263 NoV-positive specimens, 237 (90.1%) were NoV GII, 21 (8.0%) were NoV GI, and 5 (1.9%) were a combination of NoV GI and GII. Among the 216 sequenced GII-positive samples, GII.4 was the most common genotype (70.4%, 152/216), followed by GII.13 (9.3%, 20/216). GII.4 Sydney_2012 was first detected in August 2012 and replaced GII.4 Den Haag_2006b as the predominant variant between September 2012 and March 2013. With the emergence of the GII.4 Sydney_2012 variant, 44.6% more patients with diarrhea visited the 17 hospitals (9,931 cases) than in the previous year (6,866 cases) between October and December 2012.
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Affiliation(s)
- Zhiyong Gao
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing, China
| | - Xitai Li
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing, China
| | - Hanqiu Yan
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing, China
| | - Weihong Li
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing, China
| | - Lei Jia
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing, China
| | - Li Hu
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing, China
| | - Hong Hu
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing, China
| | - Baiwei Liu
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing, China
| | - Jie Li
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing, China
| | - Quanyi Wang
- Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Prevention and Control, Beijing, China
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Abstract
Norovirus is a major cause of viral gastroenteritis and a common cause of foodborne and waterborne outbreaks. Norovirus outbreaks are responsible for economic losses, most notably to the public health and food industry field. Norovirus has characteristics such as low infectious dose, prolonged shedding period, strong stability, great diversity, and frequent genome mutations. Besides these characteristics, they are known for rapid and extensive spread in closed settings such as hospitals, hotels, and schools. Norovirus is well known as a major agent of food-poisoning in diverse settings in South Korea. For these reasons, nationwide surveillance for norovirus is active in both clinical and environmental settings in South Korea. Recent studies have reported the emergence of variants and novel recombinants of norovirus. In this review, we summarized studies on the molecular epidemiology and nationwide surveillance of norovirus in South Korea. This review will provide information for vaccine development and prediction of new emerging variants of norovirus in South Korea.
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Affiliation(s)
- Sung-Geun Lee
- Korea Zoonosis Research Institute, Chonbuk National University, Iksan 570-390, Korea
| | - Han-Gil Cho
- Division of Public Health Research, Gyeonggi Province Institute of Health and Environment, Suwon 440-290, Korea
| | - Soon-Young Paik
- Department of Microbiology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea
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Personalized genetic testing and norovirus susceptibility. CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY 2014; 25:222-4. [PMID: 25285128 PMCID: PMC4173944 DOI: 10.1155/2014/708579] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND: The availability of direct-to-consumer personalized genetic testing has enabled the public to access and interpret their own genetic information. Various genetic traits can be determined including resistance to norovirus through a nonsense mutation (G428A) in the FUT2 gene. Although this trait is believed to confer resistance to the most dominant norovirus genotype (GII.4), the spectrum of resistance to other norovirus strains is unknown. The present report describes a cluster of symptomatic norovirus GI.6 infection in a family identified to have norovirus resistance through personalized genetic testing. CASE PRESENTATION: In January 2013, four members of a family determined by a direct-to-consumer genetic test to be homozygous for the norovirus resistance trait (A/A genotype for single nucleotide polymorphism rs601338) developed symptoms consistent with acute viral gastroenteritis. Stool and vomitus samples were submitted for enteric viral pathogen testing. Samples were positive for norovirus GI.6 in three of the four cases. CONCLUSIONS: The present report is the first to describe norovirus GI.6 infection in patients with the G428A nonsense mutation in FUT2; this cluster of cases suggests that the G428A mutation in FUT2 may not confer resistance to norovirus GI.6. Direct-to-consumer genetic testing is empowering members of the public to identify novel associations with their genetic traits. Expert consultation is important for the interpretation of personalized genetic test results, and follow-up laboratory testing can confirm any potentially novel associations.
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Hasing ME, Hazes B, Lee BE, Preiksaitis JK, Pang XL. Detection and analysis of recombination in GII.4 norovirus strains causing gastroenteritis outbreaks in Alberta. INFECTION GENETICS AND EVOLUTION 2014; 27:181-92. [DOI: 10.1016/j.meegid.2014.07.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 06/25/2014] [Accepted: 07/15/2014] [Indexed: 12/21/2022]
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RNA populations in immunocompromised patients as reservoirs for novel norovirus variants. J Virol 2014; 88:14184-96. [PMID: 25275120 DOI: 10.1128/jvi.02494-14] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
UNLABELLED Noroviruses are the leading cause of acute gastroenteritis outbreaks worldwide. The majority of norovirus outbreaks are caused by genogroup II.4 (GII.4). Novel GII.4 strains emerge every 2 to 4 years and replace older variants as the dominant norovirus. Novel variants emerge through a combination of recombination, genetic drift, and selection driven by population immunity, but the exact mechanism of how or where is not known. We detected two previously unknown novel GII.4 variants, termed GII.4 UNK1 and GII.4 UNK2, and a diverse norovirus population in fecal specimens from immunocompromised individuals with diarrhea after they had undergone bone marrow transplantation. We hypothesized that immunocompromised individuals can serve as reservoirs for novel norovirus variants. To test our hypothesis, metagenomic analysis of viral RNA populations was combined with a full-genome bioinformatic analysis of publicly available GII.4 norovirus sequences from 1974 to 2014 to identify converging sites. Variable sites were proportionally more likely to be within two amino acids (P < 0.05) of positively selected sites. Further analysis using a hypergeometric distribution indicated that polymorphic site distribution was random and its proximity to positively selected sites was dependent on the size of the norovirus genome and the number of positively selected sites.In conclusion, random mutations may have a positive impact on driving norovirus evolution, and immunocompromised individuals could serve as potential reservoirs for novel GII.4 strains. IMPORTANCE Norovirus is the most common cause of viral gastroenteritis in the United States. Every 2 to 3 years novel norovirus variants emerge and replace dominant strains. The continual emergence of novel noroviruses is believed to be caused by a combination of genetic drift, population immunity, and recombination, but exactly how this emergence occurs remains unknown. In this study, we identified two novel GII.4 variants in immunocompromised bone marrow transplant patients. Using metagenomic and bioinformatic analysis, we showed that most genetic polymorphisms in the novel variants occur near 0 to 2 amino acids of positively selected sites, but the distribution of mutations was random; clustering of polymorphisms with positively selected sites was a result of genome size and number of mutations and positively selected sites. This study shows that immunocompromised patients can harbor infectious novel norovirus variants, and although mutations in viruses are random, they can have a positive effect on viral evolution.
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Mans J, Murray TY, Taylor MB. Novel norovirus recombinants detected in South Africa. Virol J 2014; 11:168. [PMID: 25228444 PMCID: PMC4181420 DOI: 10.1186/1743-422x-11-168] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 09/12/2014] [Indexed: 12/26/2022] Open
Abstract
Background Noroviruses (NoV) are the leading cause of viral gastroenteritis worldwide. Recombination frequently occurs within and between NoV genotypes and recombinants have been implicated in sporadic cases, outbreaks and pandemics of NoV. There is a lack of data on NoV recombinants in Africa and therefore their presence and diversity was investigated in South Africa (SA). Results Between 2010 and 2013, eleven types of NoV recombinants were identified in SA. Amplification of the polymerase/capsid region spanning the ORF1/2 junction and phylogenetic analysis confirmed each of the recombinant types. SimPlot and maximum x2 analysis indicated that all recombinants had a breakpoint in the region of the ORF1/2 junction (P < 0.05). The majority (9/11) were intergenotype recombinants, but two intragenotype GII.4 recombinants were characterised. Three combinations represent novel recombinants namely GII.P not assigned (NA)/GII.3, GII.P4 New Orleans 2009/GII.4 NA and GII.P16/GII.17. Several widely reported recombinants were identified and included GII.P21/GII.2, GII.P21/GII.3, GII.Pe/GII.4 Sydney 2012, and GII.Pg/GII.12. Other recombinants that were identified were GII.Pg/GII.1, GII.Pe/GII.4 Osaka 2007, GII.P4 New Orleans 2009/GII.4 Sydney 2012, GII.P7/GII.6. To date these recombinant types all have a reportedly restricted geographic distribution. This is the first report of the GII.P4 New Orleans 2009/GII.4 Sydney 2012 recombinant in Africa. Conclusions Over the past four years, remarkably diverse NoV recombinants have been circulating in SA. Pandemic strains such as the GII.Pe/GII.4 Sydney 2012 recombinant co-circulated with novel and emerging recombinant strains. Combined polymerase- and capsid-based NoV genotyping is essential to determine the true diversity and global prevalence of these viruses.
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Affiliation(s)
- Janet Mans
- Department of Medical Virology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
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Cho HG, Lee SG, Kim JE, Yu KS, Lee DY, Park PH, Yoon MH, Jho EH, Kim J, Paik SY. Molecular epidemiology of norovirus GII.4 variants in children under 5 years with sporadic acute gastroenteritis in South Korea during 2006-2013. J Clin Virol 2014; 61:340-4. [PMID: 25223918 DOI: 10.1016/j.jcv.2014.08.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 08/12/2014] [Accepted: 08/24/2014] [Indexed: 01/18/2023]
Abstract
BACKGROUND The global emergence of norovirus (NoV) GII.4 variants has raised public concerns in the world including South Korea since 1996. OBJECTIVE We analyzed seasonality and genotypic pattern for sporadic cases by norovirus GII-4 variants. STUDY DESIGN To determine the epidemic status of GII.4 variants in South Korea during 2006-2013, 7301 fecal specimens were collected from children who were younger than 5 years and had sporadic acute gastroenteritis (AGE). RESULTS During the study period, NoVs were the most prevalent viral agent, detected in 877 (12.0%) of the 7301 fecal specimens from children with sporadic AGE. NoV GII strains predominantly accounted for 97.6% of all sporadic NoV infections. NoV GII.4 was the most prevalent genotype and comprised 67.6% of the NoV GII strains. However, seasonal prevalence of GII.4 strains varied depending on the spread of GII.4 variants. GII.4-2006b variant most predominantly circulated from 2006-2007 to 2009-2010 and persisted during other seasons. GII.4-2009 variant was first detected in January 2010 and predominant in 2011-2012. However, it was rapidly displaced by GII.4-2012 variant, which emerged in May 2012 and substantially circulated in 2012-2013. CONCLUSIONS The frequent emergence and rapid spread of GII.4 variants significantly affect the magnitude of sporadic NoV infections in children. Hence, to minimize the disease burden of NoV infections, GII.4 strains should be considered as a primary target for vaccine development against NoVs.
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Affiliation(s)
- Han-Gil Cho
- Division of Virology, Gyeonggi Provincial Research Institute of Public Health and Environment, Suwon, Republic of Korea; Department of Life Science, The University of Seoul, Seoul, Republic of Korea
| | - Sung-Geun Lee
- Korea Zoonosis Research Institute, Chonbuk National University, Iksan, Republic of Korea
| | - Ju-Eun Kim
- Department of Microbiology, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Kyeong-Sin Yu
- Division of Virology, Gyeonggi Provincial Research Institute of Public Health and Environment, Suwon, Republic of Korea
| | - Deog-Yong Lee
- Division of Enteric Disease, Center for Infectious Disease, National Institute of Health, Korea Centers for Disease Control and Prevention, Osong, Republic of Korea
| | - Po-Hyun Park
- Division of Virology, Gyeonggi Provincial Research Institute of Public Health and Environment, Suwon, Republic of Korea
| | - Mi-Hye Yoon
- Division of Virology, Gyeonggi Provincial Research Institute of Public Health and Environment, Suwon, Republic of Korea
| | - Eek-Hoon Jho
- Department of Life Science, The University of Seoul, Seoul, Republic of Korea
| | - Jaehong Kim
- Department of Biochemistry, School of Medicine, Gachon University, Incheon, Republic of Korea.
| | - Soon-Young Paik
- Department of Microbiology, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
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Rooney BL, Pettipas J, Grudeski E, Mykytczuk O, Pang XL, Booth TF, Hatchette TF, LeBlanc JJ. Detection of circulating norovirus genotypes: hitting a moving target. Virol J 2014; 11:129. [PMID: 25037234 PMCID: PMC4112979 DOI: 10.1186/1743-422x-11-129] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 07/06/2014] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Although national surveillance programs are in place to monitor norovirus epidemiology, the emergence of new strains and the genetic diversity among genotypes can be challenging for clinical laboratories. This study evaluated the analytical and clinical performance characteristics of one real-time RT-PCR and two end-point RT-PCRs commonly used in microbiology laboratories. METHODS Lower limit of detection (LoD) was determined using 10-fold dilutions of noroviruses belonging to different genotypes. The clinical performance of the real-time and end-point RT-PCRs was assessed in parallel using nucleic acids extracted from 186 stool specimens. RESULTS The real-time RT-PCR was highly sensitive and specific for the detection of norovirus genotypes that are currently circulating in Canada. In contrast, the two end-point RT-PCRs displayed poor analytical sensitivity or complete failure to detect certain norovirus genotypes, which was correlated to sequence mismatches in the primer-binding sites. In an attempt to improve norovirus detection with the end-point RT-PCRs, both assays were processed concurrently and detection from either assay was considered a positive result. Concurrent testing resulted in only a modest increase in clinical sensitivity (75.0%) compared to each assay alone (62.5% and 71.9%). However, the false positivity rate increased from 1.98% and 3.36% for the assays alone to 5.47% with concurrent testing. CONCLUSIONS This study emphasizes the benefits of a real-time method and provides support for routine surveillance to monitor norovirus epidemiology and ongoing proficiency testing to ensure detection of circulating norovirus genotypes.
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Affiliation(s)
- Brenda-Lee Rooney
- Dalhousie University, Halifax, Nova Scotia, Canada
- Division of Microbiology, Department of Pathology and Laboratory Medicine, Capital District Health Authority (CDHA), Dalhousie University, Halifax, Nova Scotia, Canada
| | - Janice Pettipas
- Division of Microbiology, Department of Pathology and Laboratory Medicine, Capital District Health Authority (CDHA), Dalhousie University, Halifax, Nova Scotia, Canada
| | - Elsie Grudeski
- Enteroviruses and Enteric Viruses Laboratory, National Microbiology Laboratory (NML), Winnipeg, Manitoba, Canada
| | - Oksana Mykytczuk
- Food Virology Reference Centre, Bureau of Microbial Hazards, Health Canada, Ottawa, Ontario, Canada
| | - Xiao-Li Pang
- Provincial Laboratory for Public Health (ProvLab), Edmonton, Alberta, Canada
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, Canada
| | - Tim F Booth
- Enteroviruses and Enteric Viruses Laboratory, National Microbiology Laboratory (NML), Winnipeg, Manitoba, Canada
| | - Todd F Hatchette
- Dalhousie University, Halifax, Nova Scotia, Canada
- Division of Microbiology, Department of Pathology and Laboratory Medicine, Capital District Health Authority (CDHA), Dalhousie University, Halifax, Nova Scotia, Canada
| | - Jason J LeBlanc
- Dalhousie University, Halifax, Nova Scotia, Canada
- Division of Microbiology, Department of Pathology and Laboratory Medicine, Capital District Health Authority (CDHA), Dalhousie University, Halifax, Nova Scotia, Canada
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Kim JE, Lee SG, Cho HG, Han SH, Kang LH, Lee YM, Park CJ, Paik SY. Genetic analysis of the capsid region of norovirus GII.4 variants isolated in South Korea. J Microbiol 2014; 52:427-34. [DOI: 10.1007/s12275-014-3538-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 11/08/2013] [Accepted: 11/11/2013] [Indexed: 12/26/2022]
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Structural analysis of determinants of histo-blood group antigen binding specificity in genogroup I noroviruses. J Virol 2014; 88:6168-80. [PMID: 24648450 DOI: 10.1128/jvi.00201-14] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
UNLABELLED Human noroviruses (NoVs) cause acute epidemic gastroenteritis. Susceptibility to the majority of NoV infections is determined by genetically controlled secretor-dependent expression of histo-blood group antigens (HBGAs), which are also critical for NoV attachment to host cells. Human NoVs are classified into two major genogroups (genogroup I [GI] and GII), with each genogroup further divided into several genotypes. GII NoVs are more prevalent and exhibit periodic emergence of new variants, suggested to be driven by altered HBGA binding specificities and antigenic drift. Recent epidemiological studies show increased activity among GI NoVs, with some members showing the ability to bind nonsecretor HBGAs. NoVs bind HBGAs through the protruding (P) domain of the major capsid protein VP1. GI NoVs, similar to GII, exhibit significant sequence variations in the P domain; it is unclear how these variations affect HBGA binding specificities. To understand the determinants of possible strain-specific HBGA binding among GI NoVs, we determined the structure of the P domain of a GI.7 clinical isolate and compared it to the previously determined P domain structures of GI.1 and GI.2 strains. Our crystallographic studies revealed significant structural differences, particularly in the loop regions of the GI.7 P domain, altering its surface topography and electrostatic landscape and potentially indicating antigenic variation. The GI.7 strain bound to H- and A-type, Lewis secretor, and Lewis nonsecretor families of HBGAs, allowing us to further elucidate the structural determinants of nonsecretor HBGA binding among GI NoVs and to infer several contrasting and generalizable features of HBGA binding in the GI NoVs. IMPORTANCE Human noroviruses (NoVs) cause acute epidemic gastroenteritis. Recent epidemiological studies have shown increased prevalence of genogroup I (GI) NoVs. Although secretor-positive status is strongly correlated with NoV infection, cases of NoV infection associated with secretor-negative individuals are reported. Biochemical studies have shown that GI NoVs exhibit genotype-dependent binding to nonsecretor histo-blood group antigens (HBGAs). From our crystallographic studies of a GI.7 NoV, in comparison with previous studies on GI.1 and GI.2 NoVs, we show that genotypic differences translate to extensive structural changes in the loop regions that significantly alter the surface topography and electrostatic landscape of the P domain; these features may be indicative of antigenic variations contributing to serotypic differentiation in GI NoVs and also differential modulation of the HBGA binding characteristics. A significant finding is that the threshold length and the structure of one of the loops are critical determinants in the binding of GI NoVs to nonsecretor HBGAs.
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Bruggink L, Dunbar N, Marshall J. Emergence of GII.e as a major ORF 1 norovirus genotype and its associated ORF 2 GII.4 variant forms. INFECTION GENETICS AND EVOLUTION 2014; 22:157-63. [DOI: 10.1016/j.meegid.2014.01.025] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 01/20/2014] [Accepted: 01/21/2014] [Indexed: 10/25/2022]
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Giammanco GM, De Grazia S, Terio V, Lanave G, Catella C, Bonura F, Saporito L, Medici MC, Tummolo F, Calderaro A, Bányai K, Hansman G, Martella V. Analysis of early strains of the norovirus pandemic variant GII.4 Sydney 2012 identifies mutations in adaptive sites of the capsid protein. Virology 2014; 450-451:355-8. [PMID: 24503099 DOI: 10.1016/j.virol.2013.12.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Revised: 11/18/2013] [Accepted: 12/08/2013] [Indexed: 01/14/2023]
Abstract
Global surveillance for norovirus identified in 2012 the emergence of a novel pandemic GII.4 variant, termed Sydney 2012. In Italy, the novel pandemic variant was identified as early as November 2011 but became predominant only in the winter season 2012-2013. Upon sequencing and comparison with strains of global origin, the early Sydney 2012 strains were found to differ from those spreading in 2012-2013 in the capsid (ORF2) putative epitopes B, C and D, segregating into a distinct phylogenetic clade. At least three residues (333, 340 and 393, in epitopes B, C and D, respectively) of the VP1 varied among Sydney 2012 strains of different clades. These findings suggest that the spread of the pandemic variant in Italy during the winter season 2012-2013 was due to the introduction of strains distinct from those circulating at low frequency in the former winter season and that similar strains were also circulating elsewhere worldwide.
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Affiliation(s)
- G M Giammanco
- Dipartimento di Scienze per la Promozione della Salute e Materno Infantile "G. D'Alessandro", Università di Palermo, Via del vespro 133, Palermo 90127, Italia.
| | - S De Grazia
- Dipartimento di Scienze per la Promozione della Salute e Materno Infantile "G. D'Alessandro", Università di Palermo, Via del vespro 133, Palermo 90127, Italia
| | - V Terio
- Dipartimento di Medicina Veterinaria, Università Aldo Moro di Bari, Valenzano, Italia
| | - G Lanave
- Dipartimento di Medicina Veterinaria, Università Aldo Moro di Bari, Valenzano, Italia
| | - C Catella
- Dipartimento di Medicina Veterinaria, Università Aldo Moro di Bari, Valenzano, Italia
| | - F Bonura
- Dipartimento di Scienze per la Promozione della Salute e Materno Infantile "G. D'Alessandro", Università di Palermo, Via del vespro 133, Palermo 90127, Italia
| | - L Saporito
- Dipartimento di Scienze per la Promozione della Salute e Materno Infantile "G. D'Alessandro", Università di Palermo, Via del vespro 133, Palermo 90127, Italia
| | - M C Medici
- Dipartimento di Medicina Clinica e Sperimentale, Unità di Microbiologia e Virologia, Università degli Studi di Parma, Parma, Italia
| | - F Tummolo
- Dipartimento di Medicina Clinica e Sperimentale, Unità di Microbiologia e Virologia, Università degli Studi di Parma, Parma, Italia
| | - A Calderaro
- Dipartimento di Medicina Clinica e Sperimentale, Unità di Microbiologia e Virologia, Università degli Studi di Parma, Parma, Italia
| | - K Bányai
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - G Hansman
- Schaller Research Group at the University of Heidelberg and the DKFZ, Heidelberg, Germany; Department of Infectious Diseases, Virology, University of Heidelberg, Germany
| | - V Martella
- Dipartimento di Medicina Clinica e Sperimentale, Unità di Microbiologia e Virologia, Università degli Studi di Parma, Parma, Italia
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Abstract
PURPOSE OF REVIEW Noroviruses (NoVs) are the most common cause of epidemic and sporadic cases of acute gastroenteritis worldwide. This review summarizes recent NoV disease burden estimates, epidemiology findings and provides an update on virus-like particle (VLP) vaccine studies. RECENT FINDINGS NoVs are the leading cause of food-borne gastroenteritis and are replacing rotavirus as the predominant gastrointestinal pathogen in pediatric populations. Genogroup II, genotype 4 NoVs (GII.4) remain the dominant genotype worldwide. Increased NoV activity reported in late 2012 was associated with the emergence of a new GII.4 variant called Sydney 2012. New studies suggest that human NoVs can bind a larger range of histoblood group antigens, a susceptibility factor for NoV illness, thus expanding the susceptible population pool for infection. Intranasal immunization with a monovalent GI NoV VLP vaccine showed proof-of-concept efficacy. Studies using intramuscular immunization with a bivalent formulation including GII.4 VLPs are now underway. SUMMARY The importance of NoVs as a major gastrointestinal pathogen underscores the need for well tolerated and effective vaccines. Results of VLP vaccine trials appear promising. However, the rapid evolution of NoV genotypes through antigenic drift and changing glycan specificities provide new challenges to epidemiology studies and vaccine trials.
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Eden JS, Hewitt J, Lim KL, Boni MF, Merif J, Greening G, Ratcliff RM, Holmes EC, Tanaka MM, Rawlinson WD, White PA. The emergence and evolution of the novel epidemic norovirus GII.4 variant Sydney 2012. Virology 2013; 450-451:106-13. [PMID: 24503072 DOI: 10.1016/j.virol.2013.12.005] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 12/04/2013] [Accepted: 12/06/2013] [Indexed: 12/15/2022]
Abstract
Norovirus is the leading cause of acute gastroenteritis with most infections caused by GII.4 variants. To understand the evolutionary processes that contribute to the emergence of GII.4 variants, we examined the molecular epidemiology of norovirus-associated acute gastroenteritis in Australia and New Zealand from 893 outbreaks between 2009 and 2012. Throughout the study GII.4 New Orleans 2009 was predominant; however, during 2012 it was replaced by an emergent GII.4 variant, Sydney 2012. An evolutionary analysis of capsid gene sequences was performed to determine the origins and selective pressures driving the emergence of these recently circulating GII.4 variants. This revealed that both New Orleans 2009 and Sydney 2012 share a common ancestor with GII.4 Apeldoorn 2007. Furthermore, pre-epidemic ancestral variants of each virus were identified up to two years before their pandemic emergence. Adaptive changes at known blockade epitopes in the viral capsid were also identified that likely contributed to their emergence.
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Affiliation(s)
- John-Sebastian Eden
- Marie Bashir Institute for Infectious Diseases and Biosecurity, School of Biological Sciences and Sydney Medical School, The University of Sydney, Sydney, NSW 2006, Australia; School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney, NSW 2052, Australia
| | - Joanne Hewitt
- The Institute of Environmental Science and Research Ltd (ESR), Porirua, New Zealand
| | - Kun Lee Lim
- School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney, NSW 2052, Australia; Molecular Laboratory, Department of Pathology, Singapore General Hospital, Singapore
| | - Maciej F Boni
- Oxford University Clinical Research Unit, Wellcome Trust Major Overseas Programme, Ho Chi Minh City, Vietnam; Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - Juan Merif
- Virology Division, Department of Microbiology, SEALS, Prince of Wales Hospital, Randwick, NSW, Australia
| | - Gail Greening
- The Institute of Environmental Science and Research Ltd (ESR), Porirua, New Zealand
| | - Rodney M Ratcliff
- Microbiology and Infectious Diseases, SA Pathology, Adelaide, SA, Australia
| | - Edward C Holmes
- Marie Bashir Institute for Infectious Diseases and Biosecurity, School of Biological Sciences and Sydney Medical School, The University of Sydney, Sydney, NSW 2006, Australia
| | - Mark M Tanaka
- School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney, NSW 2052, Australia
| | - William D Rawlinson
- School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney, NSW 2052, Australia; Virology Division, Department of Microbiology, SEALS, Prince of Wales Hospital, Randwick, NSW, Australia; School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
| | - Peter A White
- School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney, NSW 2052, Australia.
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Lee BE, Pang XL. New strains of norovirus and the mystery of viral gastroenteritis epidemics. CMAJ 2013; 185:1381-2. [PMID: 24003105 DOI: 10.1503/cmaj.130426] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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