The Clinical Analysis And Genotyping Of Child Intestinal Virus Meningitis/Encephalitis In Zhejiang Area

Viral meningitis/encephalitis is one of common central nervous system diseases which is caused by a variety of viruses.Among these viruses,Enterovirus(EV)has become the main pathogen.And children are widely susceptible to this disease.In recent years,the local outbreaks of intestinal virus meningitis/encephalitis(EVME)caused by enterovirus(EV)have been repeatedly in our country and caused severe symptoms and even death which poses a serious threat to children's health.Objectives:1.Investigating children with EVME infections from 2013 to 2015 in Zhejiang area and understanding the epidemiological characteristics of this disease which provide reliable basis for surveillance and precaution of this disease.2.Understanding the clinical features of this disease and finding the factors affecting the hospitalization days by analyzing the clinical data of EVME cases,this may help assess the severity and outcome of the disease.3.Studying the genotyping through sequencing the virus VP1 gene which help us know the distribution of EV genotyping and prevalence rule of the disease in Zhejiang area.Methods:Selecting the children diagnosed with intracranial infection in the children's hospital Zhejiang university school of medicine from January 2013 to December 2015.Extracting and reversely translating enterovirus RNA from the cerebrospinal fluid samples.After the reverse transcription,amplify the intestinal virus VP1 gene through nested PCR reaction.The PCR products were subjected to gel electrophoresis detection and sequencing.Analyze the sequencing results by using Sequencher software and BLAST analysis when compared with GenBank database.Then construct the evolutionary tree through Mega 5.1 software.Collect and analyze the clinical data of children with intestinal virus through PCR examination.And summarize prevalence rule and clinical features of EVME children.For normal distribution data,analyze the influence factors of EVME children hospitalization days by using multiple linear regression analysis through SPSS 19.0 statistical software,and P<0.05 was considered as statistically significant.Results:1.Epidemiological characteristics:in this study,120 cases were confirmed as EVME with 70 boys(58.3%),50 girls(41.7%),and the male/female ratio was 1.4:1.The age distribution showed 43 under 1 month(35.8%),15 cases 1 month?1 year old children(12.5%),9 cases 1-3 years old children(7.5%),25 cases 3 years old to 6 years old children(20.8%),28 cases(23.3%)>6 years old children.The incidence peaks were June to August 2013,June to July and September to October2014,June to November 2015.2.Clinical characteristic:the main clinical symptoms of the disease in children were headache,emesis,fever,symptoms of other systems were rare.Among laboratory examinations,myocardial enzymes were often elevated.White blood cells were at normal levels in blood routine examination.However,in cerebrospinal fluid examination,leukocytes slightly increased and proteins increased obviously.3.Statistical analysis of clinical data:by analyzing the clinical data,the factors affecting hospitalization days were myocardial enzymes,protein concentration in the cerebrospinal fluid,spasm.4.The genotyping,homology and evolutionary tree analysis:30 cases(10 cases per year)were randomly selected,and then extracted EV nucleic acid,amplified and sequenced VP1 gene.Sequencing results showed that 18 Echo 30,4 Echo 16,3 CVB2,3 Echo5,2 CVB3.The homology between strains were greater than 85%.Echo 30 was close to Zhejiang reported strains,Echo 16 and CVB3 were similar to reported strains in Yunnan province,CVB3 type was related to reported strains in Shanghai.Echo 5 was close to Iran reported stains.Conclusion:1.The incidence peak was June to October by analyzing EVME cases from 2013 to 2015 in Zhejiang area,Main clinical symptoms were fever,headache,emesis,often accompanied by myocardial damage.Cerebrospinal fluid protein level were often higher than other VME.2.The main factors affecting the hospitalization days were myocardial enzyme spectrum values,protein content in the cerebrospinal fluid,and spasms.3.The main strain of the patients' samples was Echo 30.The sporadic strains were Echo 16,CVB B2,Echo5,CVB B3.According to the analysis of the evolutionary tree,Echo 30 may be another outbreak of isolates in Zhejiang province,other sporadic EV strains were far away from Zhejiang isolates,this may be because of a long-distance move.EV have many types,different types may outbreak in different periods.