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Shirai T, Phadungsombat J, Ushikai Y, Yoshikaie K, Shioda T, Sakon N. Epidemiological Features of Human Norovirus Genotypes before and after COVID-19 Countermeasures in Osaka, Japan. Viruses 2024; 16:654. [PMID: 38675994 PMCID: PMC11055107 DOI: 10.3390/v16040654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 04/19/2024] [Accepted: 04/19/2024] [Indexed: 04/28/2024] Open
Abstract
We investigated the molecular epidemiology of human norovirus (HuNoV) in all age groups using samples from April 2019 to March 2023, before and after the COVID-19 countermeasures were implemented. GII.2[P16] and GII.4[P31], the prevalent strains in Japan before COVID-19 countermeasures, remained prevalent during the COVID-19 pandemic, except from April to November 2020; in 2021, the prevalence of GII.2[P16] increased among children. Furthermore, there was an increase in the prevalence of GII.4[P16] after December 2022. Phylogenetic analysis of GII.P31 RdRp showed that some strains detected in 2022 belonged to a different cluster of other strains obtained during the present study period, suggesting that HuNoV strains will evolve differently even if they have the same type of RdRp. An analysis of the amino acid sequence of VP1 showed that some antigenic sites of GII.4[P16] were different from those of GII.4[P31]. The present study showed high infectivity of HuNoV despite the COVID-19 countermeasures and revealed changes in the prevalent genotypes and mutations of each genotype. In the future, we will investigate whether GII.4[P16] becomes more prevalent, providing new insights by comparing the new data with those analyzed in the present study.
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Affiliation(s)
- Tatsuya Shirai
- Department of Microbiology, Osaka Institute of Public Health, Osaka 537-0025, Japan; (T.S.)
| | | | - Yumi Ushikai
- Department of Microbiology, Osaka Institute of Public Health, Osaka 537-0025, Japan; (T.S.)
| | - Kunihito Yoshikaie
- Department of Microbiology, Osaka Institute of Public Health, Osaka 537-0025, Japan; (T.S.)
| | - Tatsuo Shioda
- Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan;
| | - Naomi Sakon
- Department of Microbiology, Osaka Institute of Public Health, Osaka 537-0025, Japan; (T.S.)
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Jacobsen S, Faber M, Altmann B, Mas Marques A, Bock CT, Niendorf S. Impact of the COVID-19 pandemic on norovirus circulation in Germany. Int J Med Microbiol 2024; 314:151600. [PMID: 38246091 DOI: 10.1016/j.ijmm.2024.151600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/14/2023] [Accepted: 01/15/2024] [Indexed: 01/23/2024] Open
Abstract
Human norovirus is a major cause of viral gastroenteritis in all age groups. The virus is constantly and rapidly changing, allowing mutations and recombination events to create great diversity of circulating viruses. With the start of the COVID-19 pandemic in 2020, a wide range of public health measures were introduced worldwide to control human-to-human transmission of SARS-CoV-2. In Germany, control measures such as distance rules, contact restrictions, personal protection equipment as well as intensive hand hygiene were introduced. To better understand the effect of the measures to control the COVID-19 pandemic on incidence and the molecular epidemiological dynamics of norovirus outbreaks in Germany, we analyzed national notification data between July 2017 and December 2022 and characterized norovirus sequences circulating between January 2018 and December 2022. Compared to a reference period before the pandemic, the incidence of notified norovirus gastroenteritis decreased by 89.7% to 9.6 per 100,000 during the 2020/2021 norovirus season, corresponding to an incidence rate ratio (IRR) of 0.10. Samples from 539 outbreaks were genotyped in two regions of the viral genome from pre-pandemic (January 2018 to February 2020) and samples from 208 outbreaks during pandemic time period (March 2020 to December 2022). As expected, norovirus outbreaks were mainly found in child care facilities and nursing homes. In total, 36 genotypes were detected in the study period. A high proportion of recombinant strains (86%) was found in patients, the proportion of detected recombinant viruses did not vary between the pre-pandemic and pandemic phase. The proportion of the predominant recombinant strain GII.4 Sydney[P16] was unchanged before pandemic and during pandemic at 37.5%. The diversity of most common genotypes in nursing homes and child care facilities showed a different proportion of genotypes causing outbreaks. In nursing homes as well as in child care facilities GII.4 Sydney[P16] was predominant during the whole study period. Compared to the nursing homes, a greater variety of genotypes at the expense of GII.4 Sydney[P16] was detected in child care facilities. Furthermore, the overall proportion of recombinant strain GII.3[P12] increased during the pandemic, due to outbreaks in child care facilities. The COVID-19 pandemic had a high impact on the occurrence of sporadic cases and norovirus outbreaks in Germany, leading to a near suppression of the typical norovirus winter season following the start of the pandemic. The number of norovirus-associated outbreak samples sent to the Consultant Laboratory dropped by 63% during the pandemic. We could not identify a clear influence on circulating norovirus genotypes. The dominance of GII.4 Sydney recombinant strains was independent from the pandemic. Further studies are needed to follow up on the diversity of less predominant genotypes to see if the pandemic could have acted as a bottleneck to the spread of previously minoritized genotypes like GII.3[P12].
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Affiliation(s)
- Sonja Jacobsen
- Consultant Laboratory for Norovirus, Department of Infectious Diseases, Robert Koch Institute, 13353 Berlin, Germany
| | - Mirko Faber
- Department of Infectious Disease Epidemiology, Robert Koch Institute, 13353 Berlin, Germany
| | - Britta Altmann
- Department of Infectious Disease, Robert Koch Institute, 13353 Berlin, Germany
| | - Andreas Mas Marques
- Consultant Laboratory for Norovirus, Department of Infectious Diseases, Robert Koch Institute, 13353 Berlin, Germany
| | - C-Thomas Bock
- Department of Infectious Disease, Robert Koch Institute, 13353 Berlin, Germany
| | - Sandra Niendorf
- Consultant Laboratory for Norovirus, Department of Infectious Diseases, Robert Koch Institute, 13353 Berlin, Germany.
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Khamrin P, Kumthip K, Yodmeeklin A, Okitsu S, Motomura K, Sato S, Ushijima H, Maneekarn N. Genetic recombination and genotype diversity of norovirus GI in children with acute gastroenteritis in Thailand, 2015-2021. J Infect Public Health 2024; 17:379-385. [PMID: 38237357 DOI: 10.1016/j.jiph.2024.01.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 01/02/2024] [Accepted: 01/08/2024] [Indexed: 02/19/2024] Open
Abstract
BACKGROUND Human norovirus is a predominant etiological agent responsible for acute gastroenteritis across all age groups. Recently, norovirus recombinant strains have been reported as the cause of norovirus outbreaks in several settings and the strains that cause outbreaks mostly belong to the norovirus GII. However, yet, the norovirus GI recombinant strains have never been reported previously in Thailand. The aims of this study were to investigate the genetic recombination and genotype diversity of norovirus GI strains in children hospitalized with acute gastroenteritis in Chiang Mai, Thailand during a period of seven years from 2015 to 2021. METHODS A total of 2829 stool specimens were screened for norovirus GI by real-time PCR, and the polymerase and capsid genes were sequenced and analyzed. RESULTS Of 2829 specimens tested, 12 (0.4%) were positive for norovirus GI. Of these, 7 out of 12 (58.3%) strains were identified as norovirus GI recombinant strains. Among 7 norovirus GI recombinant strains, 3, 3, and 1 were identified as GI.3[P13], GI.5[P4], and GI.6[P11], respectively. The remaining five strains were identified as non-recombinant strains of the GI.4[P4], GI.5[P5], and GI.6[P6] genotypes. CONCLUSIONS The findings highlight the genetic diversity and multiple intergenotype recombinant strains of norovirus GI circulating in children with acute gastroenteritis in Chiang Mai, Thailand from 2015 to 2021. The detection of multiple intergenotype norovirus GI recombinant strains further underscore the complexity of norovirus GI strains circulating in this region.
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Affiliation(s)
- Pattara Khamrin
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; Center of Excellence in Emerging and Re-emerging Diarrheal Viruses, Chiang Mai University, Chiang Mai, Thailand; Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, Japan
| | - Kattareeya Kumthip
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; Center of Excellence in Emerging and Re-emerging Diarrheal Viruses, Chiang Mai University, Chiang Mai, Thailand
| | - Arpaporn Yodmeeklin
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; Center of Excellence in Emerging and Re-emerging Diarrheal Viruses, Chiang Mai University, Chiang Mai, Thailand
| | - Shoko Okitsu
- Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, Japan
| | - Kazushi Motomura
- Epidemiology Section, Division of Public Health, Osaka Institute of Public Health, Osaka, Japan
| | - Shintaro Sato
- Department of Microbiology and Immunology, School of Pharmaceutical Sciences, Wakayama Medical University, Wakayama, Japan
| | - Hiroshi Ushijima
- Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, Japan
| | - Niwat Maneekarn
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; Center of Excellence in Emerging and Re-emerging Diarrheal Viruses, Chiang Mai University, Chiang Mai, Thailand.
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Sarmento SK, de Andrade JDSR, Malta FC, Fialho AM, Mello MDS, Burlandy FM, Fumian TM. Norovirus Epidemiology and Genotype Circulation during the COVID-19 Pandemic in Brazil, 2019-2022. Pathogens 2023; 13:3. [PMID: 38276149 PMCID: PMC10818385 DOI: 10.3390/pathogens13010003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 12/07/2023] [Accepted: 12/11/2023] [Indexed: 01/27/2024] Open
Abstract
Norovirus stands out as a leading cause of acute gastroenteritis (AGE) worldwide, affecting all age groups. In the present study, we investigated fecal samples from medically attended AGE patients received from nine Brazilian states, from 2019 to 2022, including the COVID-19 pandemic period. Norovirus GI and GII were detected and quantified using RT-qPCR, and norovirus-positive samples underwent genotyping through sequencing the ORF1/2 junction region. During the four-year period, norovirus prevalence was 37.2%, varying from 20.1% in 2020 to 55.4% in 2021. GII genotypes dominated, being detected in 92.9% of samples. GII-infected patients had significantly higher viral concentrations compared to GI-infected patients (median of 3.8 × 107 GC/g and 6.7 × 105 GC/g, respectively); and patients aged >12-24 months showed a higher median viral load (8 × 107 GC/g) compared to other age groups. Norovirus sequencing revealed 20 genotypes by phylogenetic analysis of RdRp and VP1 partial regions. GII.4 Sydney[P16] was the dominant genotype (57.3%), especially in 2019 and 2021, followed by GII.2[P16] (14.8%) and GII.6[P7] (6.3%). The intergenogroup recombinant genotype, GIX.1[GII.P15], was detected in five samples. Our study is the first to explore norovirus epidemiology and genotype distribution in Brazil during COVID-19, and contributes to understanding the epidemiological dynamics of norovirus and highlighting the importance of continuing to follow norovirus surveillance programs in Brazil.
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Affiliation(s)
| | | | | | | | | | | | - Tulio Machado Fumian
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro 21045-900, RJ, Brazil (F.M.B.)
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Sá R, Roque J, Marques Mendes P, Gonçalves I, Sousa J, Matos C, Júnior Á, Coelho A, Belo Correia C, Manageiro V, Minetti C, de Sousa R, Horta Correia F. Prevention, protocols, and lab capacity: lessons from a norovirus outbreak in the Algarve. Arch Virol 2023; 168:299. [PMID: 38015274 DOI: 10.1007/s00705-023-05926-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 10/16/2023] [Indexed: 11/29/2023]
Abstract
This brief report presents the findings of an epidemiological investigation into a large-scale outbreak of norovirus gastroenteritis that occurred in a hotel in Algarve, Portugal, in August 2022. A total of 244 cases were reported, primarily affecting Portuguese families, with the parents aged 40-50 years and the children aged 0-19 years. Reported symptoms included vomiting, nausea, abdominal pain, and diarrhoea. Norovirus genotype GI.3 [P3] was detected in stool samples from eight probable cases, while food samples tested negative for norovirus and common pathogenic bacteria. The investigation data collected suggest that the source of the outbreak was likely in the hotel's common areas, with subsequent person-to-person transmission in other areas. The final report emphasizes the importance of improving outbreak prevention and control measures, including the development of a foodborne outbreak investigation protocol, the establishment of an outbreak response team, and the enhancement of regional laboratory capacity.
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Affiliation(s)
- Regina Sá
- Public Health Unit, Algarve Central Health Centre Grouping, Regional Health Administration of Algarve, Faro, Portugal.
| | - Joana Roque
- Public Health Unit, Algarve Central Health Centre Grouping, Regional Health Administration of Algarve, Faro, Portugal
| | - Pedro Marques Mendes
- Public Health Unit, Algarve Central Health Centre Grouping, Regional Health Administration of Algarve, Faro, Portugal
| | - Inês Gonçalves
- Public Health Unit, Algarve Barlavento Health Centre Grouping, Regional Health Administration of Algarve, Portimão, Portugal
| | - Judite Sousa
- Personalized Health Care Unit (UCSP) Albufeira, Algarve Central Health Centre Grouping, Regional Health Administration of Algarve, Albufeira, Portugal
| | - Cátia Matos
- Personalized Health Care Unit (UCSP) Albufeira, Algarve Central Health Centre Grouping, Regional Health Administration of Algarve, Albufeira, Portugal
| | | | - Anabela Coelho
- Department of Food and Nutrition, National Institute of Health Doutor Ricardo Jorge, Lisbon, Portugal
| | - Cristina Belo Correia
- Department of Food and Nutrition, National Institute of Health Doutor Ricardo Jorge, Lisbon, Portugal
| | - Vera Manageiro
- Department of Infectious Diseases, National Institute of Health Doutor Ricardo Jorge, Lisbon, Portugal
- European Public Health Microbiology Training Programme (EUPHEM), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
| | - Corrado Minetti
- Department of Infectious Diseases, National Institute of Health Doutor Ricardo Jorge, Lisbon, Portugal
- European Public Health Microbiology Training Programme (EUPHEM), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
| | - Rita de Sousa
- Department of Infectious Diseases, National Institute of Health Doutor Ricardo Jorge, Lisbon, Portugal
| | - Filomena Horta Correia
- Public Health Unit, Algarve Central Health Centre Grouping, Regional Health Administration of Algarve, Faro, Portugal
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Qi Y, Dong X, Cheng X, Xu H, Wang J, Wang B, Chen Y, Sun B, Zhang L, Yao Y. Epidemiological Characteristics of Norovirus Outbreaks in Shenyang from 2017 to 2021. J Microbiol 2023; 61:471-478. [PMID: 36972002 DOI: 10.1007/s12275-023-00033-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 02/17/2023] [Accepted: 02/17/2023] [Indexed: 03/29/2023]
Abstract
Norovirus is one of the leading causes of acute gastroenteritis outbreaks worldwide. This study aimed to identify the epidemiological characteristics of norovirus outbreaks and to provide evidence for public health entities. Specimens and epidemiological survey data were collected to determine if there were differences in the attack rate of norovirus in terms of the year, season, transmission route, exposure setting, and region and to determine whether there were relationships between the reporting interval, the number of illnesses in a single outbreak and the duration of the outbreak. Norovirus outbreaks were reported throughout the year, with seasonal characteristics (i.e., high rates in spring and winter). Among all regions in Shenyang with the exception of Huanggu and Liaozhong, norovirus outbreaks had been reported, and the primary genotype was GII.2[P16]. Vomiting was the most common symptom. The main places of occurrence were childcare institutions and schools. The person-to-person route was the main transmission route. The median duration of norovirus was 3 days (IQR [interquartile range]: 2-6 days), the median reporting interval was 2 days (IQR: 1-4 days), the median number of illnesses in a single outbreak was 16 (IQR: 10-25); there was a positive correlation between these parameters. Norovirus surveillance and genotyping studies still need to be further strengthened to increase knowledge regarding the pathogens and their variant characteristics, to better characterize the patterns of norovirus outbreaks and to provide information for outbreak prevention. Norovirus outbreaks should be detected, reported and handled early. Public health entities and the government should develop corresponding measures for different seasons, transmission routes, exposure settings, and regions.
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Affiliation(s)
- Ying Qi
- Shenyang Center for Disease Control and Prevention, Shenyang, 110102, Liaoning, People's Republic of China
| | - Xinxin Dong
- Department of Epidemiology and Biostatistics, School of Public Health, Jilin University, Changchun, 130021, Jilin, People's Republic of China
| | - Xiaowei Cheng
- Department of Epidemiology and Biostatistics, School of Public Health, Jilin University, Changchun, 130021, Jilin, People's Republic of China
| | - Han Xu
- Department of Epidemiology and Biostatistics, School of Public Health, Jilin University, Changchun, 130021, Jilin, People's Republic of China
| | - Jin Wang
- Department of Epidemiology and Biostatistics, School of Public Health, Jilin University, Changchun, 130021, Jilin, People's Republic of China
| | - Bing Wang
- Shenyang Center for Disease Control and Prevention, Shenyang, 110102, Liaoning, People's Republic of China
| | - Ye Chen
- Shenyang Center for Disease Control and Prevention, Shenyang, 110102, Liaoning, People's Republic of China
| | - Baijun Sun
- Shenyang Center for Disease Control and Prevention, Shenyang, 110102, Liaoning, People's Republic of China
| | - Linlin Zhang
- Shenyang Center for Disease Control and Prevention, Shenyang, 110102, Liaoning, People's Republic of China
| | - Yan Yao
- Department of Epidemiology and Biostatistics, School of Public Health, Jilin University, Changchun, 130021, Jilin, People's Republic of China.
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Alarcón-Linares ME, Moreno-Docón A, Pérez-Serna L, Camacho J, Rodriguez DS, Gutiérrez-Martín ML, Broncano-Lavado A, Echevarria JE, Cabrerizo M, Fernández-García MD. Rare Recombinant GI.5[P4] Norovirus That Caused a Large Foodborne Outbreak of Gastroenteritis in a Hotel in Spain in 2021. Microbiol Spectr 2023; 11:e0485722. [PMID: 36809021 PMCID: PMC10100975 DOI: 10.1128/spectrum.04857-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Accepted: 01/25/2023] [Indexed: 02/23/2023] Open
Abstract
Noroviruses are among the most important causes of acute gastroenteritis (AGE). In summer 2021, a large outbreak of norovirus infections affecting 163 patients, including 15 norovirus-confirmed food handlers, occurred in a hotel in Murcia in southeast Spain. A rare GI.5[P4] norovirus strain was identified as the cause of the outbreak. The epidemiological investigation determined that norovirus transmission might have been initiated through an infected food handler. The food safety inspection found that some symptomatic food handlers continued working during illness. Molecular investigation with whole-genome and ORF1 sequencing provided enhanced genetic discrimination over ORF2 sequencing alone and enabled differentiation of the GI.5[P4] strains into separate subclusters, suggesting different chains of transmission. These recombinant viruses have been identified circulating globally over the last 5 years, warranting further global surveillance. IMPORTANCE Due to the large genetic diversity of noroviruses, it is important to enhance the discriminatory power of typing techniques to differentiate strains when investigating outbreaks and elucidating transmission chains. This study highlights the importance of (i) using whole-genome sequencing to ensure genetic differentiation of GI noroviruses to track chains of transmission during outbreak investigations and (ii) the adherence of symptomatic food handlers to work exclusion rules and strict hand hygiene practices. To our knowledge, this study provides the first full-length genome sequences of GI.5[P4] strains apart from the prototype strain.
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Affiliation(s)
| | - Antonio Moreno-Docón
- Hospital Universitario Virgen de la Arrixaca, Murcia, Spain
- IMIB—Arrixaca, Universidad de Murcia, Murcia, Spain
| | | | - Juan Camacho
- Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Spain
| | | | | | - Antonio Broncano-Lavado
- Instituto de Investigación Sanitaria—Fundación Jiménez Díaz Hospital Universitario, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
| | - Juan-Emilio Echevarria
- Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Spain
- CIBER de Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - María Cabrerizo
- Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Spain
- CIBER de Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - María D. Fernández-García
- Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Spain
- CIBER de Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
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Zhou N, Huang Y, Zhou L, Li M, Jin H. Molecular Evolution of RNA-Dependent RNA Polymerase Region in Norovirus Genogroup I. Viruses 2023; 15:166. [PMID: 36680206 PMCID: PMC9861054 DOI: 10.3390/v15010166] [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: 11/17/2022] [Revised: 01/03/2023] [Accepted: 01/04/2023] [Indexed: 01/06/2023] Open
Abstract
Norovirus is the leading viral agent of gastroenteritis in humans. RNA-dependent RNA polymerase (RdRp) is essential in the replication of norovirus RNA. Here, we present a comprehensive evolutionary analysis of the norovirus GI RdRp gene. Our results show that the norovirus GI RdRp gene can be divided into three groups, and that the most recent common ancestor was 1484. The overall evolutionary rate of GI RdRp is 1.821 × 10-3 substitutions/site/year. Most of the amino acids of the GI RdRp gene were under negative selection, and only a few positively selected sites were recognized. Amino acid substitutions in the GI RdRp gene accumulated slowly over time. GI.P1, GI.P3 and GI.P6 owned the higher evolutionary rates. GI.P11 and GI.P13 had the faster accumulation rate of amino acid substitutions. GI.P2, GI.P3, GI.P4, GI.P6 and GI.P13 presented a strong linear evolution. These results reveal that the norovirus GI RdRp gene evolves conservatively, and that the molecular evolutionary characteristics of each P-genotype are diverse. Sequencing in RdRp and VP1 of norovirus should be advocated in the surveillance system to explore the effect of RdRp on norovirus activity.
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Affiliation(s)
- Nan Zhou
- Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, Department of Epidemiology and Health Statistics, School of Public Health, Southeast University, Nanjing 210009, China
| | - Yue Huang
- Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, Department of Epidemiology and Health Statistics, School of Public Health, Southeast University, Nanjing 210009, China
| | - Lu Zhou
- Department of Acute Infectious Diseases, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing 210009, China
| | - Mingma Li
- Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, Department of Epidemiology and Health Statistics, School of Public Health, Southeast University, Nanjing 210009, China
| | - Hui Jin
- Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, Department of Epidemiology and Health Statistics, School of Public Health, Southeast University, Nanjing 210009, China
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