OBJECTIVES: To study the molecular epidemiological characteristics of the virus in children with acute viral diarrhea in Changdu of Tibet, China. METHODS: Fecal specimens were collected from 96 children with acute diarrhea who visited the People's Hospital of Changdu, Tibet, from November 2018 to November 2020 and were tested for adenovirus, norovirus, astrovirus, sapovirus, and rotavirus. Gene sequencing was performed for the genotypes of these viruses. RESULTS: The overall positive rate of the five viruses was 39% (37/96), among which astrovirus had the highest positive rate of 17%, followed by norovirus (9%), rotavirus (8%), adenovirus (7%), and sapovirus (5%). There was no significant difference in the positive rate of the five viruses among different age groups (P>0.05). Only the positive rate of astrovirus was significantly different among the four seasons (P<0.05). For adenovirus, 6 children had F41 type and 1 had C2 type; for norovirus, 6 had GⅠ.3 type, 1 had GⅠ.7 type, 1 had GⅡ.3 type, and 2 had GⅡ.4 Sydney_2012 type; HAstrV-1 type was observed in all children with astrovirus infection; for sapovirus, 1 child each had sporadic GⅠ.2, GⅠ.6, and GⅡ.1 sapovirus and 2 children had unknown type; 6 children had rotavirus G9[P8]. CONCLUSIONS Astrovirus and norovirus are important pathogens in children with acute diarrhea in Changdu, Tibet. The positive rate of adenovirus, norovirus, astrovirus, sapovirus, and rotavirus is not associated with age, and only the positive rate of astrovirus has obvious seasonality. F41 type is the dominant genotype of adenovirus; GⅠ.3 is the dominant genotype of norovirus; HAstrV-1 is the dominant genotype of astrovirus; sporadic GⅠ.2, GⅠ.6, and GⅡ.1 are the dominant genotypes of sapovirus; G9[P8] is the dominant genotype of rotavirus.
Child ; China ; Diarrhea/epidemiology* ; Feces ; Gastroenteritis ; Humans ; Tibet/epidemiology* ; Viruses/genetics*

OBJECTIVES: To study the molecular epidemiological characteristics of norovirus in children with acute gastroenteritis from 2017 to 2019. METHODS: A retrospective analysis was performed on the medical data of children with acute gastroenteritis who were admitted to Children's Hospital of Chongqing Medical University from January 2017 to December 2019. A total of 1 458 stool samples were collected from the children, and viral RNA was extracted. Reverse transcription polymerase chain reaction was used for gene amplification, sequencing, and genotype identification of the VP1 region of capsid protein in norovirus. RESULTS: Among the 1 458 stool samples, 158 (10.8%) were positive for norovirus. There was no significant difference in the positive detection rate of norovirus between different years ( CONCLUSIONS Norovirus GII.4 Sydney 2012 was the major epidemic strain in the children with norovirus gastroenteritis from 2017 to 2019. Although norovirus infection can exist throughout the year, August to October is the peak period. During this period, norovirus surveillance and key population protection are strengthened to help prevent and control norovirus diarrhea.
Child ; Feces ; Female ; Gastroenteritis/epidemiology* ; Humans ; Male ; Norovirus/genetics* ; Phylogeny ; Retrospective Studies

Objective: To understand the epidemiological and etiological characteristics of outbreaks on acute gastroenteritis caused by sapovirus (SaV) worldwide. Methods: Literature about the outbreaks on acute gastroenteritis caused by SaV were retrieved from the databases including WanFang, CNKI, PubMed and Web of Science after evaluation. Time, geography, setting and population distributions of outbreaks, transmission mode, SaV genotype and clinical characteristics of the patients were analyzed. Results: A total of 34 papers about SaV were included, involving 146 outbreaks occurred between October 1976 and April 2016. In these papers, 138 outbreaks were reported on the related months. All these outbreaks occurred in northern hemisphere. SaV outbreaks occurred all year around, but mainly in cold season, the incidence was highest in December (25 outbreaks) and lowest in in August (2 outbreaks). Most outbreaks were reported by Japan, followed by Canada, the United States of America and the Netherlands. There were 141 outbreaks for which the occurring settings were reported, child-care settings were most commonly reported setting (48/141, 34.04%), followed by long-term care facility (41/141, 29.08%) and hospital (16/141, 11.35%). Clinical symptoms of 1 704 cases in 31 outbreaks were reported, with the most common symptom was diarrhea (1 331/1 704, 78.12%), followed by nausea (829/1 198, 69.20%), abdominal pain (840/1 328, 63.25%), vomiting (824/1 704, 48.36%) and fever (529/1 531, 34.53%). Genotypes of SaV were determined for 119 outbreaks. GⅠ(51/119, 42.86%) and GⅣ (45/119, 37.82%) were predominant. The outbreaks of GⅣ SaV increased suddenly in 2007, and the outbreaks of GⅠ SaV mainly occurred in 2008 and during 2011-2013. Conclusions: SaV outbreaks were reported mainly by developed countries, with most outbreaks occurred in cold season, in child-care settings and long term care facility. GⅠ and GⅣ were the most common genotypes of SaV. Prevention and control of SaV outbreak in China seemed relatively weak, and it is necessary to conduct related training and to strengthen the SaV outbreak surveillance in areas where service is in need.
Caliciviridae Infections/virology* ; Child ; China/epidemiology* ; Disease Outbreaks ; Feces/virology* ; Gastroenteritis/virology* ; Genotype ; Humans ; Phylogeny ; RNA, Viral/genetics* ; Sapovirus/isolation & purification* ; Sequence Analysis, DNA

Acute Disease ; epidemiology ; Adenovirus Infections, Human ; epidemiology ; virology ; Adenoviruses, Human ; genetics ; physiology ; Child, Preschool ; China ; epidemiology ; Feces ; virology ; Female ; Gastroenteritis ; epidemiology ; virology ; Genotype ; Humans ; Infant ; Infant, Newborn ; Male ; Prevalence ; Rotavirus ; genetics ; physiology ; Rotavirus Infections ; epidemiology ; virology

Objective: To analyze the genetic characterization of norovirus isolated in an outbreak of gastroenteritis in Jiangsu province. Methods: Extracted viral RNA from the swab samples of cases of acute gastroenteritis outbreak in Jiangsu province on December 16-27, 2016 was reversely transcribed to cDNA, and partial RNA-dependent RNA polymerase sequence and complete capsid sequence (VP1) were amplified by RT-PCR. Amplification products were sequenced for the analysis of genetic characteristics. Results: Based on sequence alignment, the variant shared a high level of identity with the strain GⅡ.g isolated in Spain and Finland (98.7%) in the RNA-dependent RNA polymerase region, and with the strain GⅡ.1 isolated in American (99.4%) in the VP1. The recombination was determined by using software Simplot, and the breakpoint of recombination was located in the ORF1/2 overlap region at position 5 106 of VP1. The result of amino acids alignment in capsid region showed that there were no mutations in the amino acids of the predicted epitopes and receptor binding site Ⅰ-Ⅲ, but a unique amino acid change was detected at position 132 (N-S). Conclusion: The norovirus isolated in the outbreak of gastroenteritis in Jiangsu province was a rare recombinant norovirus variant GⅡ.g-GⅡ.1.
Caliciviridae Infections/epidemiology* ; Capsid Proteins ; Disease Outbreaks ; Gastroenteritis/epidemiology* ; Genotype ; Humans ; Norovirus/isolation & purification* ; Phylogeny ; RNA, Viral/genetics* ; Reverse Transcriptase Polymerase Chain Reaction ; Sequence Analysis, DNA

Noroviruses are the leading cause of epidemic gastroenteritis, including foodborne outbreak, in Korea. The prevalence of human noroviruses was studied in diarrheal stool samples of patients with acute gastroenteritis by conventional duplex reverse transcription (RT)-PCR. Diarrheal stool samples were collected from 1,685 patients from the local hospitals in Seoul. The prevalence of the noroviruses was 22.8% (222/972 patients) in 2012 and 11.2% (80/713 patients) in 2013, with a total of 17.9% (302/1,685 patients). Genotyping was performed on 302 norovirus-positive stool samples to reveal 5.6% prevalence of genogroup I (GI) (17/302) and 94.4% prevalence of genogroup II (GII) (285/302). The patients with norovirus-associated acute gastroenteritis mostly showed prevalence of GII norovirus, especially GII.4 (64.6%; 195/302).
Acute Disease ; Feces/virology ; Gastroenteritis/*diagnosis/epidemiology/virology ; Genotype ; Humans ; Norovirus/*genetics/isolation & purification ; Prevalence ; RNA, Viral/genetics/metabolism ; Real-Time Polymerase Chain Reaction

The prevalence of human astroviruses was tested in patients with acute gastroenteritis by using conventional duplex reverse transcription (RT)-PCR and electrophoresis. Diarrheal fecal samples were collected from 9,597 patients at local hospitals in Seoul. The prevalence of astroviruses was 1.0% (94/9,597 patients; mostly infants), and that of sapoviruses was 0.1% (14/9,597 patients). Age- and gender-wise analyses were carried out on 29 astrovirus-positive patients having complete information on file regarding their age, gender, and other particulars. The results were higher in patients of ages 0 to 14 yr, and 69.0% of the astrovirus-positive patients were females, of which 69.2% were infants (0 to 12 months), and 61.5% were 1-4 yr old. Notably, in the case of 5 to 78-yr-old acute gastroenteritis patients, 100% were females.
Acute Disease ; Adolescent ; Adult ; Age Factors ; Aged ; Astroviridae Infections/complications/*epidemiology/virology ; Child ; Child, Preschool ; DNA, Viral/analysis ; Feces/virology ; Female ; Gastroenteritis/complications/*diagnosis ; Humans ; Infant ; Male ; Mamastrovirus/genetics/*isolation & purification ; Middle Aged ; Prevalence ; Reverse Transcriptase Polymerase Chain Reaction ; Sapovirus/genetics/isolation & purification ; Sex Factors ; Young Adult

OBJECTIVETo monitor the epidemiology of norovirus infection in diarrheal children in Shanghai between 2009 and 2011 and characterize the genotypes of norovirus strains.

METHODThe stool samples were collected from children visiting outpatient clinic for acute non-dysenteric diarrhea between 2009 and 2011.One step real-time RT-PCR was used for screening norovirus genogroups GI and GII. The genotypes of norovirus genogroup GII were classified based on the nucleotide sequences of both partial capsid and polymerase fragments.

RESULTA total of 2 288 outpatient children with acute diarrhea were included in this study, out of whom, 531 (23.1%) were positive for norovirus in the fecal specimens based on real-time RT-PCR test.Norovirus was prevalent throughout the year and an increased activity of norovirus infection was usually observed between July and October. Children <4 years of age accounted for 95.2% of norovirus-infected cases, and the detection rate of norovirus was significantly higher in diarrheal children <4 years than in those ≥ 4 years (24.4% vs. 10.7%,χ(2) = 10.66, P < 0.05).Of 531 norovirus-positive specimens, 4 (1.7%) were positive for genogroup GI and 527 (98.3%) positive for genogroup GII. Seven distinct capsid genotypes were identified in 234 norovirus strains, including 153 (64.4%) GII.4 (9 belonging to 2010 variants and 145 belonging to 2006b variants), 66 (27.6%) GII.3, 7 (2.9%) GII.2, 6 (2.5%) GII.6, 4 (1.7%) GII.12, 1 (0.4%) GII.7 and GII.14 in each. Seven polymerase genotypes were identified in 244 norovirus strains, including 189 (77.5%) GII.4 (14 belonging to 2010 variants and 175 belonging to 2006b variants), 47 (19.3%) GII.12, 2 (0.8%) GII.16, GII.b and GII.g in each, 1 (0.4%) GII.2 and GII.6 in each. A new GII.4-2010 (New Orleans) variant was first detected in June 2010 and sporadically circulated afterwards.Of 198 norovirus strains in which both polymerase and capsid genotypes were determined, 56 showed discordant results, indicating potential norovirus recombinants. The common discordant combinations of the polymerase and capsid genotypes were GII.12/GII.3 (69.6%) and GII.4/GII.3 (8.9%).

CONCLUSIONNorovirus is a common causative agent responsible for diarrhea in Shanghai children over the three years and norovirus-associated diarrhea was epidemic year round with high activity in late summer and autumn in Shanghai.Infants and young children are susceptible to norovirus infection. The circulating norovirus showed genetic diversity. The GII.4-2006b variant continued to predominate in Shanghai during the period of 2009-2011 despite the emergence of the novel GII.4-2010 (New Orleans) variant.

Adolescent ; Caliciviridae Infections ; epidemiology ; virology ; Capsid Proteins ; genetics ; Child ; Child, Preschool ; China ; epidemiology ; Diarrhea ; epidemiology ; virology ; Feces ; virology ; Female ; Gastroenteritis ; epidemiology ; virology ; Genetic Variation ; Genotype ; Humans ; Infant ; Male ; Molecular Epidemiology ; Norovirus ; classification ; genetics ; isolation & purification ; Prevalence ; RNA, Viral ; genetics ; isolation & purification ; Reverse Transcriptase Polymerase Chain Reaction ; Sequence Analysis, DNA

To describe the epidemiological characteristics of norovirus (NOV) associated acute gastroenteritis in Shanghai and characterize the evolution pattern of circulating strains. From March 2012 to February 2013, 502 stool specimens were collected from adult (> or = 16 years) outpatients who visited either of the two sentinel hospitals in Shanghai for acute gastroenteritis. Molecular detection and genotyping of NoV were performed and the phylogenetic relationship of the circulating strains has also been comprehensively analyzed. The epidemics level of GI NoV was low throughout the surveillance period, with the positive rate of 3.78% (19 cases), and no seasonality of GI NoV infection could be distinguished. For GII genogroup, higher epidemics in adults in Shanghai, with the detection rate of 17.13% (86 cases), were observed. And relatively high epidemics of GII NoV infection were spotted between October and December in 2012. The frequency of NoV associated acute gastroenteritis in older people is significantly higher than that in young individuals (P < 0.05). Sequencing and genotyping analysis revealed that the high epidemics of GII NoV infection between October and December in 2012 is associated with the emergence of a novel GII.4 norovirus strain, termed Sydney_2012. Sequence analysis also demonstrated that this was a recombinant virus between a GII.e polymerase and GII.4 capsid, which has also been the dominant circulating strain in Shanghai. In 2012, a new GII.4 variant, termed Sydney_2012, emerged in Shanghai and caused high epidemics of acute gastroenteritis during late autumn and winter.
Adolescent ; Adult ; Aged ; Caliciviridae Infections ; epidemiology ; virology ; China ; epidemiology ; Disease Outbreaks ; Female ; Gastroenteritis ; epidemiology ; virology ; Genotype ; Humans ; Male ; Middle Aged ; Norovirus ; chemistry ; classification ; genetics ; isolation & purification ; Phylogeny ; Viral Envelope Proteins ; chemistry ; genetics ; Young Adult

Caliciviridae Infections ; epidemiology ; virology ; Gastroenteritis ; virology ; Genetic Variation ; Genotype ; Humans ; Norovirus ; classification ; genetics