Etiology And Clinical Characteristics Study On Norovirus Diarrhea In52Children

Objectives: The purpose of the study was to investigate the etiology characteristics ofNorovirus diarrhea in children, to analyze the molecular biology feature of Norovirus,to understand the clinical characteristics of Norovirus diarrhea in children and toprovide the scientific basis for prevention and treatment of Norovirus. Methods:311fecal specimens of acute viral diarrhea inpatients were collected from ChangchunChildren’s Hospital between January2013and January2014. The fecal specimenswere detected for Norovirus by the method of reverse transcription-polymerase chainreaction (RT-PCR). We used the primer P289/929. RNA was extracted by the methodof Trizol. Some of the positive samples were sequenced and compared with theclassical Norovirus sequences that were deposited in Genbank. The multiplesequences were aligned by using the software of Clustal W. The homology ofnucleotide sequence was evaluated with DNAMAN software and the phylogenetictree of partial polymerase region was generated by Mega6.0software. The clinicaldata were collected. The data was analyzed by using SPSS software version17.0．Results: Total311fecal specimens of acute viral diarrhea inpatients weredetected from Changchun Children’s Hospital between January2013and January2014. There were52positive specimens. The detection rate of Norovirus infectionwas16.72%(52/311).9of them were sequenced, out of which5were successful.5sequenced strains belonged to NoV GⅡ group.4sequenced strains clustered with theNorovirus GⅡ.4genotype. These4sequences had high identities to the strain Sakaiobtained from Japan.1sequenced strain clustered with the Norovirus GⅡ.6genotypewhich had high identity to the strains Saitama and Ehime obtained from Japan.Norovirus could be detected every month. Not seasonal obvious. The proportionbetween boys and girls was1.08:1. The difference of the detection rate of Noroviruswas not significant between different sexes. The detection rate of Norovirus in＜1year old group was32.35%(33/102), higher than＞1year old group. The clinicalsymptoms of Norovirus infection were diarrhea, fever, vomiting. Diarrhea was thecommon symptom in children of Norovirus infection. The proportion of fever and vomiting were69.23%(36/52) and61.54%(32/52). The dehydration was48.08%(25/52), the myocardial injury was44.23%(23/52) and the respiratory complicationwas48.08%(25/52). Finally, all the patients were clinically cured or improved afterthe treatment. Average day of hospital stay was5.5±1.45days. Conclusions:1.Norovirus was the important pathogen causing acute viral diarrhea in children.2.There were different genotypes circulated in children. Norovirus GⅡ.4was thepredominant genotype in this study. The GⅡ.6was first reported in Changchun area.3. The detection rate of Norovirus was mainly distributed in children under1year old.4. The symptoms were diarrhea, vomiting, fever.