Noroviruses are the leading cause of acute gastroenteritis in humans. Real-time reverse transcription-polymerase chain reaction(real-time RT-PCR) is a promising molecular method for the detection of noroviruses. In th...Noroviruses are the leading cause of acute gastroenteritis in humans. Real-time reverse transcription-polymerase chain reaction(real-time RT-PCR) is a promising molecular method for the detection of noroviruses. In this study, the performance of three Taq Man real-time RT-PCR assays was assessed, which were one commercially available real-time RT-PCR kit(assay A:Norovirus Real Time RT-PCR kit) and two in-house real-time RT-PCR assays(assay B: Light Cycler RNA Master Hybprobe and assay C: Real Time ready RNA Virus Master). Assays A and B showed higher sensitivity than assay C for norovirus GI, while they all had the same sensitivity(103 DNA copies/m L) for GII DNA standard controls. Assay B had the highest efficiency for both genogroups.No cross-reactivity was observed among GI and GII noroviruses, rotavirus, hepatitis A virus, and poliovirus. The detection rates of these assays in GI and GII norovirus-positive fecal samples were not significantly different. However, the mean quantification cycle(Cq) value of assay B for GII was lower than assays A and C with statistical significance(P-value, 0.000). All three real-time RT-PCR assays could detect a variety of noroviruses including GI.2, GII.2, GII.3, GII.4, GII.6, GII.12, GII.17,and GII.21. This study suggests assay B as a suitable assay for the detection and quantification of noroviruses GI and GII due to good analytical sensitivity and higher performance to amplify norovirus on DNA standard controls and clinical samples.展开更多
Coxsackievirus A10(CVA10)is one of the major causative agents of hand,foot and mouth disease(HFMD).To investigate the epidemiological characteristics as well as genetic features of CVA10 currently circulating in Shang...Coxsackievirus A10(CVA10)is one of the major causative agents of hand,foot and mouth disease(HFMD).To investigate the epidemiological characteristics as well as genetic features of CVA10 currently circulating in Shanghai,China,we collected a total of 9,952 sporadic HFMD cases from January 2016 to December 2020.In the past five years,CVA10 was the fourth prevalent causatives associated with HFMD in Shanghai and the overall positive rate was 2.78%.The annual distribution experienced significant fluctuations over the past five years.In addition to entire VP1 sequencing,complete genome sequencing and recombination analysis of CVA10 isolates in Shanghai were further performed.A total of 64 near complete genomes and 11 entire VP1 sequences in this study combined with reference sequences publicly available were integrated into phylogenetic analysis.The CVA10sequences in this study mainly belonged to genogroup C and presented 91%-100%nucleotide identity with other Chinese isolates based on VP1 region.For the first time,our study reported the appearance of CVA10 genogroup D in Chinese mainland,which had led to large-scale outbreaks in Europe previously.The recombination analysis showed the recombination break point located between 5,100 nt and 6,700 nt,which suggesting intertypic recombination with CVA16 genogroup D.To conclusion,CVA10 genogroup C was the predominant genogroup in Shanghai during 2016-2020.CVA10 recombinant genogroup D was firstly reported in circulating in Chinese mainland.Continuous surveillance is needed to better understand the evolution relationships and transmission pathways of CVA10 to help to guide disease control and prevention.展开更多
目的了解浙江省湖州市急性胃肠炎病例中GⅠ型诺如病毒的感染状况及基因型别特征。方法收集2017年4月至2018年6月湖州市2家哨点医院诊断为急性胃肠炎病例的粪便标本1 259份。采用实时荧光定量反转录–聚合酶链式反应(real time RT-PCR)...目的了解浙江省湖州市急性胃肠炎病例中GⅠ型诺如病毒的感染状况及基因型别特征。方法收集2017年4月至2018年6月湖州市2家哨点医院诊断为急性胃肠炎病例的粪便标本1 259份。采用实时荧光定量反转录–聚合酶链式反应(real time RT-PCR)对提取的病毒RNA进行GⅠ和GⅡ型诺如病毒核酸检测。采用RT-PCR对GⅠ型阳性标本进行RdRp区和VP1区部分片段的扩增和测序。综合在线分型工具和系统进化分析的结果判定病毒基因型别。结果诺如病毒核酸阳性171份,阳性率13.58%。GⅡ型和GⅠ型诺如病毒的检出阳性率分别为11.83%(149/1 259)和2.70%(34/1 259),GⅡ型诺如病毒为检出的主要型别。GⅠ型诺如病毒主要检出于2018年上半年。2018年2-6月各月GⅠ型诺如病毒的检出阳性率均大于监测期间GⅠ型的平均检出阳性率。基因分型结果显示,2018年检出的GⅠ型诺如病毒包括GⅠ.P4-GⅠ.5、GⅠ.P2-GⅠ.2、GⅠ.P1-GⅠ.1、GⅠ.Pd-GⅠ.3、GⅠ.P4-GⅠ.4、GⅠ.P2-GⅠ.5。其中GⅠ.P4-GⅠ.5、GⅠ.P2-GⅠ.5和GⅠ.Pd-GⅠ.3重组型诺如病毒首次在湖州市检出。结论湖州市流行的GⅠ型诺如病毒基因型别多样,重组现象明显。应加强GⅠ型诺如病毒在当地的分子流行病学监测,以及时发现新的变异或重组株。展开更多
AIM:To report an acute gastroenteritis outbreak caused by a genogroup 2 genotype 6(GII.6) strain norovirus in Shanghai,China.METHODS:Noroviruses are responsible for approximately half of all reported gastroenteritis o...AIM:To report an acute gastroenteritis outbreak caused by a genogroup 2 genotype 6(GII.6) strain norovirus in Shanghai,China.METHODS:Noroviruses are responsible for approximately half of all reported gastroenteritis outbreaks in many countries.Genogroup 2 genotype 4 strains are the most prevalent.Rare outbreaks caused by GII.6 strains have been reported.An acute gastroenteritis outbreak occurred in an elementary school in Shanghai in December of 2013.Field and molecular epidemiologic investigations were conducted.RESULTS:The outbreak was limited to one class in an elementary school located in southwest Shanghai.The age of the students ranged from 9 to 10 years.The first case emerged on December 10,2013,and the last case emerged on December 14,2013.The cases peaked on December 11,2013,with 21 new cases.Of 45 students in the class,32 were affected.The main symptom was gastroenteritis,and 15.6%(5/32) of the cases exhibited a fever.A field epidemiologic investigation showed the pathogen may have been transmitted to the elementary school from employees in a delicatessen via the first case student,who had eaten food from the delicatessen one day before the gastroenteritis episodes began.A molecular epidemiologic investigation identified the cause of the gastroenteritis as norovirus strain GII.6;the viral sequence of the student cases showed 100% homology with that of the shop employees.Genetic relatedness analyses showed that the new viral strain is closely related to previously reported GII.6 sequences,especially to a strain reported in Japan.CONCLUSION:This is the first report to show that norovirus strain GII.6 can cause a gastroenteritis outbreak.Thus,the prevalence of GII.6 noroviruses requires attention.展开更多
基金supported by research grant from the Thailand Research Fund (TRF) through the Royal Golden Jubilee Ph.D. program (Grant No. PHD/0085/2554)the Thai Government Budget through Mahidol University, fiscal year 2015-2017
文摘Noroviruses are the leading cause of acute gastroenteritis in humans. Real-time reverse transcription-polymerase chain reaction(real-time RT-PCR) is a promising molecular method for the detection of noroviruses. In this study, the performance of three Taq Man real-time RT-PCR assays was assessed, which were one commercially available real-time RT-PCR kit(assay A:Norovirus Real Time RT-PCR kit) and two in-house real-time RT-PCR assays(assay B: Light Cycler RNA Master Hybprobe and assay C: Real Time ready RNA Virus Master). Assays A and B showed higher sensitivity than assay C for norovirus GI, while they all had the same sensitivity(103 DNA copies/m L) for GII DNA standard controls. Assay B had the highest efficiency for both genogroups.No cross-reactivity was observed among GI and GII noroviruses, rotavirus, hepatitis A virus, and poliovirus. The detection rates of these assays in GI and GII norovirus-positive fecal samples were not significantly different. However, the mean quantification cycle(Cq) value of assay B for GII was lower than assays A and C with statistical significance(P-value, 0.000). All three real-time RT-PCR assays could detect a variety of noroviruses including GI.2, GII.2, GII.3, GII.4, GII.6, GII.12, GII.17,and GII.21. This study suggests assay B as a suitable assay for the detection and quantification of noroviruses GI and GII due to good analytical sensitivity and higher performance to amplify norovirus on DNA standard controls and clinical samples.
基金supported by Shanghai Sailing Program(Grant no:19YF1441500)Shanghai Municipal Commission of Health and Family Planning(Grant no:20184Y0101)Three-Year Action Plan of Shanghai Public Health System Construction(Grant no:GWV-2,GWV10.1-XK03)。
文摘Coxsackievirus A10(CVA10)is one of the major causative agents of hand,foot and mouth disease(HFMD).To investigate the epidemiological characteristics as well as genetic features of CVA10 currently circulating in Shanghai,China,we collected a total of 9,952 sporadic HFMD cases from January 2016 to December 2020.In the past five years,CVA10 was the fourth prevalent causatives associated with HFMD in Shanghai and the overall positive rate was 2.78%.The annual distribution experienced significant fluctuations over the past five years.In addition to entire VP1 sequencing,complete genome sequencing and recombination analysis of CVA10 isolates in Shanghai were further performed.A total of 64 near complete genomes and 11 entire VP1 sequences in this study combined with reference sequences publicly available were integrated into phylogenetic analysis.The CVA10sequences in this study mainly belonged to genogroup C and presented 91%-100%nucleotide identity with other Chinese isolates based on VP1 region.For the first time,our study reported the appearance of CVA10 genogroup D in Chinese mainland,which had led to large-scale outbreaks in Europe previously.The recombination analysis showed the recombination break point located between 5,100 nt and 6,700 nt,which suggesting intertypic recombination with CVA16 genogroup D.To conclusion,CVA10 genogroup C was the predominant genogroup in Shanghai during 2016-2020.CVA10 recombinant genogroup D was firstly reported in circulating in Chinese mainland.Continuous surveillance is needed to better understand the evolution relationships and transmission pathways of CVA10 to help to guide disease control and prevention.
文摘AIM:To report an acute gastroenteritis outbreak caused by a genogroup 2 genotype 6(GII.6) strain norovirus in Shanghai,China.METHODS:Noroviruses are responsible for approximately half of all reported gastroenteritis outbreaks in many countries.Genogroup 2 genotype 4 strains are the most prevalent.Rare outbreaks caused by GII.6 strains have been reported.An acute gastroenteritis outbreak occurred in an elementary school in Shanghai in December of 2013.Field and molecular epidemiologic investigations were conducted.RESULTS:The outbreak was limited to one class in an elementary school located in southwest Shanghai.The age of the students ranged from 9 to 10 years.The first case emerged on December 10,2013,and the last case emerged on December 14,2013.The cases peaked on December 11,2013,with 21 new cases.Of 45 students in the class,32 were affected.The main symptom was gastroenteritis,and 15.6%(5/32) of the cases exhibited a fever.A field epidemiologic investigation showed the pathogen may have been transmitted to the elementary school from employees in a delicatessen via the first case student,who had eaten food from the delicatessen one day before the gastroenteritis episodes began.A molecular epidemiologic investigation identified the cause of the gastroenteritis as norovirus strain GII.6;the viral sequence of the student cases showed 100% homology with that of the shop employees.Genetic relatedness analyses showed that the new viral strain is closely related to previously reported GII.6 sequences,especially to a strain reported in Japan.CONCLUSION:This is the first report to show that norovirus strain GII.6 can cause a gastroenteritis outbreak.Thus,the prevalence of GII.6 noroviruses requires attention.
