Epidemiological and etiological analysis of two infantile cases of serogroup B epidemic cerebrospinal meningitis epidemics in Shandong Province, 2021 / 中华预防医学杂志

Two cases of epidemic situation of serogroup B meningitis in infants in Shandong Province in 2021 were investigated. Samples of cases and their close contacts were collected for isolation, culture and identification of Neisseria meningitides (Nm). The isolates were subjected to multi-locus sequence typing, outer membrane protein porA and fetA genotyping and drug sensitivity test. Two laboratory-confirmed outbreaks of serogroup B meningitis were reported from Yantai city and Linyi city. The indicated cases were infants aged 5 months and 2 months old respectively. They were not vaccinated with meningitis vaccine. Their epidemiological characteristics and clinical manifestations were similar and the prognosis was good. The same sequence type (ST) of serogroup B Nm strains as the indicated cases was detected in the samples of close family contacts, but without subsequent cases. Among them, Yantai strain was were identified as the type ST-8920, belonging to CC4821 clonal complex, and the genotypes of porA and fetA were p1.21-2, 23 and F3-1. Linyi strain was a new type, belonging to CC4821 clonal complex and the genotypes of porA and fetA were p1.20, 23 and F1-91. The above strains were resistant to penicillin, ciprofloxacin, levofloxacin and Chemitrim, and their sensitivity to cephalosporin decreased. Two cases of infant serogroup B epidemic were relatively rare in China, which were different from the epidemiological and pathogenic characteristics of other Nm serogroups in the past.

Genetic characterization of echovirus 6 isolated from meningitis and encephalitis cases in Shandong Province, China / 病毒学报

To analyze the genetic characteristics of echovirus 6 (E6) isolated from meningitis and encephalitis cases in Shandong Province, China, we collected cerebrospinal fluid samples from meningitis and encephalitis cases in Shandong Province from 2007 to 2012 for virus isolation. Viral RNAs were extracted from positive isolates, and complete VP1 coding regions were amplified by RT-PCR and sequenced. Homology comparison and phylogenetic analysis were performed. Six isolates were identified as E6 by microneutralization assay and molecular typing. The homology analysis showed that the six isolates had 78. 6%-99. 8% nucleotide and 95. 5%-100. 0% amino acid identities with each other, as well as 76. 9%-78. 4% nucleotide and 92. 3%-95. 1% amino acid identities with the prototype strain (D' Amori). The phylogenetic analysis based on the integrated VP1 sequences indicated that all Shandong E6 isolates could be separated into four clusters, designated as A, B, C, and D. The six E6 isolates belonged to clusters A, B, and D. Our study reveals high genetic differences between Shandong E6 isolates and suggests different transmission lineages of E6 co-circulated in Shandong Province.

Identification and genetic characterization of coxsackieviruses A2, 6, 8 and 12 isolated in Shandong Province / 病毒学报

In previous study, molecular typing method was performed to identify human enteroviruses (HEVs) isolates collected from acute flaccid paralysis (AFP) cases from 1989 to 2011 and hand, foot and mouth disease (HFMD) patients, and 8 HEV-A serotypes were identified. In order to explore the genotypes and molecular evolution characteristics of HEV-A in Shandong province, viral RNA of the remaining isolates was extracted and entire VP1 coding region was amplified, sequenced and identified with HEV-A primers. Another 7 HEV-A Shandong isolates were obtained, and identified as Coxsackievirus A (CVA) 2, 6, 8 and 12 by molecular typing method. Homologous comparison showed that the nucleotide acid identities of Shandong strains ranged from 80.8% to 85.0% with prototype strains. Phylogenetic analysis based on VP1 sequences indicated that CVA8 and CVA12 strains were genetically related with domestic strains. However, CVA2 and CVA6 strains were distinct from both domestic and foreign strains. In addition, multiple transmission chains of CVA2 and CVA6 existed within Shandong province. So far, a total of 12 HEV-A serotypes were identified in Shandong province. This study enriched the distribution of serotypes and genetic evolution characteristics of HEV-A isolates in Shandong, and revealed different transmission chains of CVA2, 6, 8, 12 serotypes co-circulated in Shandong province or in China.

Study on the genetic characterization and molecular epidemiology of echovirus 11 strains isolated in Shandong province, China / 中华流行病学杂志

Objective To analyze the evolution and genetic characterization of echovirus 11 (Echo11 ) from the acute flaccid paralysis (AFP) cases in Shandong province. Methods Isolation of Enterovirus was performed from stool samples of AFP cases from 1994 to 2009. All positive strains were sero-typed by neutralization test. Entire VP1 coding region from 27 strains typed as Echo 11 was amplified by reverse transcription-polymerase chain reaction(RT-PCR), and subsequently phylogenetic analyse on VP1 sequences from these strains and others published in GenBank were conducted. Results From 1994 to 2009, altogether 915 non-polio enterovirus (NPEV) strains were isolated with 79(8.6% ) isolates serotyped as Echo11. There were 876 nucleotides (nt) in the complete VP1 genes, encoding 292 amino acids (aa). The nt identities were 76.4%-100.0% among those Echo11 Shandong strains with the aa identities as 91.4% -100.0%. The nt and aa identities were 77.7%-80.7% and 90.7%-94.8% between Shandong strains and prototype strains, respectively.Conclusion All Echo11 strains could be divided into four genotypes. Shandong strains that forming three (A1, A2 and C1) new sub-genotypes, with every sub-genotype had several brands.Sub-genotype A1 appeared to be the lately circulating one.

Identification and phylogenic analysis of Coxsackie-virus B5 during an outbreak of aseptic meningitis in Shandong / 中华流行病学杂志

Objective To identify the pathogen that caused an outbreak of aseptic meningitis in Shandong province in 2005. Phylogenic analysis was carried out on Coxsackie-virus B5 (CVB5) which was isolated during this outbreak. Methods 78 stool and 58 cerebrospinal fluids (CSF) specimens were collected from some inpatients during this outbreak. Virus isolation and reverse transcription-polymerase chain reaction (RT-PCR) was then performed. Phylo-genetic trees based on entire and partial VP1 sequences were constructed among CVB5 isolates and others published in GenBank. Results The isolation rates of stool and CSF specimens were 38.5% (30/78) and 48.3% (28/58) respectively. Among the results of serotype identification and molecular typing of 58 positive isolates, 54 were identified as CVB5, 2 as ECHO24, 1 as CVB3 and 1 as CVA9. Results from viral investigation showed that CVB5 was the main pathogen causing this outbreak. Data from homological comparisons indicated that Shandong strains had the highest nucleotide acid identity with the Zhejiang/ 12/02 strain (97.5%-97.8%), and lower identity (78.3%-78.6%) with the prototype strain (Faulkner strain). Phylogenic tree in VP1 region showed that CVB5 could be separated into four genotypes. Isolates of this outbreak belonged to genotype D. Conclusion CVB5 was the major etiological agent correlated with this outbreak. The shift of predominant genotype might serve as one of the causes that associated with the outbreaks of aseptic meningitis.

Genotype distribution of enterovirus group B isolated in Shandong Province, China / 病毒学报

In order to explore the genotype distribution of human enterovirus group B (HEV-B) in Shandong Province and to study the correlation between HEV-B serotypes and disease outbreaks, we sequenced and analyzed the entire VP1 coding region of HEV-B isolated from acute flaccid parolysis (AFP) system and disease outbreaks in Shandong province during 1998-2008. All together twenty nine HEV-B serotypes were identified, including twenty Echovirus (ECHO) serotypes, five Coxsackievirus B (CVB1-5) serotypes, one Coxsackievirus A9(CVA9) serotype, and newer enteroviruses EV73, EV75, and EV97. E11, CVB3, E6, E14 and E25 were the five frequently isolated serotypes from AFP surveillance system. CVB3, CVB5 and ECHO30 were the major causative agent of aseptic meningitis in Shandong province. Comparison of nucleotide sequence homology showed 75.4%-99.6% inter-typic identities within Shandong strains, and 73.8%-85.2% identities with prototype strains. Amino acid sequence comparison showed the differentiation was not much. Our research showed different serotypes possessed distinct time-cycling pattern, and different sub-genotypes could be further classified according to the inter-typic genetic distance. Thereby the route and range of transmission of HEV could be determined.

Genotype distribution of enterovirus group C in Shandong Province, China / 病毒学报

Human Enterovirus C group (HEV-C) includes 17 serotypes, which can not be serotype-identified by neutralization test using antiserum pool for NPEV. In order to elucidate the genotypes and molecular evolution of HEV-C in Shandong Province, We selected the strains isolated from AFP cases between 1994-2009 to perform reverse transcriptase-polymerase chain reactions (RT-PCR) by the primers specific for entire VP1 coding gene of HEV-C and sequencing. The phylogenetic tree was then constructed among these VP1 nucleotide sequences and other prototype strains. Totally 12 Shandong local strains were obtained and separated into 4 genotypes, CVA20, CVA21,CVA24 and EV 96. The homologous comparison and phylogenetic analysis showed Shandong strains were distinct from prototype strains in each genotype. This report showed that different genotype HEV-C strains spread widely in Shandong Province.

Identification and genetic characterization of human enterovirus type 73, 75, and 97 strains of specie B isolated in Shandong province / 病毒学报

Molecular typing was conducted for three human enteroviruses (HEV) isolated from acute flaccid paralysis (AFP) cases in Shandong province, China. RNAs from virus supernatants were extracted and complete VP1 genes were amplified by RT-PCR and sequenced. Genotypes of these isolates were identified as HEV type 73, 75 and 97, respectively by BLAST program. Homology and phylogenetic tree analyses were performed. Sequence analysis of VP1 gene showed significant variation compared with prototype strains. This study presents the genetic characteristics of HEV 73, 75 and 97 of specie B in Shandong Province, and the first report of HEV97 in China.

Molecular characterization of full-length genome of Japanese encephalitis virus (SD08-10) newly isolated in Shandong province / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>Sequence and analysis the complete nucleotide of the Japanese encephalitis virus (JEV) newly strain SD08-10, isolated in 2008 in Shandong, China in order to understand the characterization of the virus.</p><p><b>METHODS</b>Overlapping primers were designed according to the full-length genomes in GenBank. RT-PCR was used to amplify the fragments and the full-length genome was obtained by sequencing and splicing. Using the computer software to analysis the nucleic acid data, deduced amino acid sequence and phylogenetic tree, including Clustal X (1.8), DNASTAR, GENEDOC (3.2).</p><p><b>RESULTS</b>The result of sequence analysis shows that the genome of SD08-10 strain was 10 965 nucleotides long. An open reading frame from 96 to 10 392 including 10 296 nucleotides is capable of coding for a 3432 amino acid polyprotein. Compared with the live attenuated vaccine strain SA-14-14-2 in China, there was 1253 nucleotide difference and 82 amino acid divergence. Comparison of the complete genome sequences with 59 different JEV isolates showed a 0.7%-18.9% nucleotide sequence divergence among them, which resulted in 0.1%-5.2% amino acid sequence divergence. Phylogenetic analysis of full-length genome showed that the SD08-10 strain was belonging to genotype I.</p><p><b>CONCLUSION</b>Analysis based on the complete genome sequences of different JEV isolates showed that the SD08-10 strain isolated in 2008 in Shandong was belonging to genotype I and close to SH17M-07 isolated in 2007 in China.</p>

Molecular characterization of coxsackievirus B3 isolated from an outbreak of aseptic meningitis in Shandong Province, China / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To identify the pathogen caused an outbreak of aseptic meningitis in Tancheng county of Shandong province in 2008, and to analyze the molecular characterization of VP1 gene of the Coxsackievirus B3(CVB3) isolates.</p><p><b>METHODS</b>Stool and cerebrospinal fluid(CSF) specimens were collected from this outbreak for virus isolation with RD and Hep-2 cell. After typing by neutralization test, the VP1 gene of the isolates were amplified by RT-PCR and sequenced. Homologous comparison and phylogenetic analysis were performed.</p><p><b>RESULTS</b>35 strains of enteviruse were isolated from 22 stools and 120 CSFs(7 from stools and 28 from CSFs), 34 strains identified as CVB3 and 1 as Echovirus 30(ECHO30) by neutralization test. The nucleotide homologies were 90.5%-100.0% in the partial VP1 gene (381 bp) among 34 CVB3 isolates. Homology comparisons indicated that Shandong strains have the identity of 79.5%-81.6% with the CVB3 prototype strain Nancy. 012/2008TC/SD/CHN and 177/2008TC/SD/CHN showed the highest nucleotides homologies (98.2% and 91.0% respectively) with Fuyang19 strain of Anhui province in 2008 in complete VP1 gene. The phylogenetic tree based on complete VP1 genes showed that all the CVB3 correlated with aseptic meningitis in China recently came from the same evolution linkage and formed a monophyletic cluster.</p><p><b>CONCLUSION</b>The causative agent of this outbreak of aseptic meningitis was CVB3. CVB3 circulated in China was genetically different from other countries.</p>

Genotype distribution of enterovirus A species isolated in Shandong Province, China / 病毒学报

In order to study the genotypes and molecular evolution of human enterovirus (HEV) A species in Shandong Province, Stool samples were collected from AFP and HFMD patients in Shandong Province and virus isolation was performed. Reverse Transcription-Polymerase Chain Reactions (RT-PCR) specific for EV71 and CVA16 were performed with the virus isolates from HFMD patients. Positive isolates were selected for entire VP1 coding gene amplification and sequencing. Isolates with negative PCR results and isolates from AFP patients were selected for entire VP1 coding gene amplification and sequencing using primers specific for HEV A species. Phylogenetic tree was constructed among these VP1 nucleotide sequences and of other strains. Altogether 293 strains classified into 8 genotypes were isolated. The homologous comparison and phylogenetic analysis showed Shandong strains were distinct with prototype strains in every genotype. This report presents an overview of HEV-A in Shandong Province.

Study on the causes and risk factors on vertigo and balance disorders in 118 elderly patients / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the various factors causing vertigo and balance disorders in the elderly.</p><p><b>METHODS</b>118 elderly patients (aged equal or older than 60 years of age) with vertigo or balance disorders were retrospectively analyzed through clinical symptoms, audio-vestibular function tests, X-ray, CT scan or MRI in cervical vertebras, brain and inner ears, ultrasonography, transcranial doppler (TCD) or magnetic resonance angiography (MRA) in blood vessels on head and neck.</p><p><b>RESULTS</b>Of 118 patients, 70 (23%) of them suffered perip heral vestibular disorders while 29 (58%) having cerebral vertigo or dizzness, leaving 19 cases (16%) as unclassified.</p><p><b>CONCLUSION</b>For elderly patients, vertigo and balance disorders were commonly caused by many kinds of peripheral and cerebral vestibular pathological disfunctions while the functional weakness of vestibular organs and systems affected by the physiological process of ageing and different concommitant diseases as well as environmental, psychogenic factors should also be considered.</p>