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ABSTRACT: To explore the Fast Testing Sstrategy (FTS) for wild poliovirus I (WP1).
Epidemiological investigations were carried out on 671 students from WP1 epidemic areas in China. A set of real time RT-PCR assays, including panenterovirus testings (PE) assay, poliovirus serotypings (PS) assay and the assay distinguishing wild strain from vaccine strain of poliovirus I (DWV) were introduced into the screening program for WPV1 to replace the conventional RT-PCR, recommended by the China National Polio Laboratory (GNPL). Additionally, sensitivities of all the assays were assessed by poliovirus type I to III (Sabin stain) and the isolated WPV1.
(1) 33 non-poliovirus enterovirus (NPEV) cases were detected, with 16 polio vaccine-related cases including 5 polio I, 1 polio II, 3 polio III, 1 polio I + II, 4 polio I + III and 2 polio I + II + III. Three WPV1 cases were also detected in this study and confirmed by CNPL. (2) For polio virus vaccine strain, sensitivities of the set of real time RT-PCR assays ranged from 1 to 100 times than that of the in-house RT-PCR assay. The sensitivities of PE and PS assays for the detection of polio II were 100 times than that of the RT-PCR assay and the sensitivity of DWV assay used for the detection of polio I were 10 times than that of the RT-PCR assay. For WPV1, the sensitivity of three real time RT-PCR was 10 times hight than that of the RT-PCR assay.
The novel FTS for WPV1 suggested by this study would include PE, PS and DWV. It not only could greatly shorten the testing time but also more sensitive than the RT-PCR and suited for emergency detection for WPV1.
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 07/2012; 33(7):726-9.
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ABSTRACT: To compare the genetic characteristics of mumps virus strain circulating in Beijing with vaccine strain and to preliminarily analysis the reasons of vaccine ineffectiveness.
The following methods were used: Isolation and identification of the mumps virus which had been circulating in Beijing, immunization history analysis, SH gene sequence analysis and comparison genotype homology with reference strains and analysis of the key amino acid sites of HN variation.
In 38 mumps cases that virus had been isolated from, another seven cases were IgM negative. In 2007 and 2008, the positive rates on virus isolation, RT-PCR and IgM-decreased significantly, while the cases with immunization history had an increase. Cases without histories of vaccination had both higher positive rates on virus isolation and IgM. Thirty-eight strains belonged to F genotype virus, but vaccine strain was A genotype. The circulating viruses showed 5.6% sequence divergence on SH gene nucleotide and 16.0% - 18.1% from vaccine strain. Conservative hydrophobic amino acids on SH protein of some Beijing strains had changed. For example, there were 6 strains, from No.8: L-->F. The circulating viruses showed 2.3% sequence divergence on HN protein amino acid sequences and 4.2% - 5.3% from vaccine strain. Amino acids sites, which deciding the ability of cross-neutralization of the Beijing strains and vaccine strains were different. At the 354 and 356 sites, all the Beijing strains were different from the vaccine strains. The N-glycosylation sites on HN of Beijing strains were also different from those on vaccine strains. Locations 464 - 466 appeared to be NCS on Beijing strain, but locations 464 - 466 were NCR on the vaccine strains. Another 18 unknown function amino acids sites of all Beijing strains were different from those on vaccine strains.
In recent years, genotype F became the main genotype of circulating strains in Beijing without genotype variation, but larger difference was found between them. There was a big difference between SH and HN protein of Beijing strains and vaccine strain, which might explain the ineffectiveness of the vaccine.
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 11/2009; 30(11):1184-8.
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ABSTRACT: To identify the etiology of 8 human hand-foot-mouth disease (HFMD) outbreaks in Beijing, during May to July 2007.
Reverse transcription-polymerase chain reaction (RT-PCR) method was used to directly type the specimens including fluid from the herpes and throat swabs from the HFMD patients. Using RD cell lines, the collected stool specimens were cultured followed by typing. Partial VP1 region of selected EV positive specimens and cultures were sequenced and both nucleic acid sequence and predicted amino acid sequence were analyzed.
The two HFMD outbreaks in Daxing region in Beijing in 2007 were caused by enterovirus 71 type (EV71), and the others were caused by Coxsackie virus A16 (Cox A16). Two EV71 strains caused epidemics in Daxing region in 2007 belonged to C4 subgenotype but on different branches in VP1 gene phylogenetic tree. The differences on nucleic acid sequence and amino acid sequence were 3.7% and 0.8% between the two EV71 stains, respectively. The Cox A16 strain in Shunyi region and the other strains were on different branches in phylogenetic tree, and the difference on nucleic acid and amino acid sequence were 3.7% and 0% respectively between the two Cox A16 stains.
The HFMD outbreaks occurred in Beijing in 2007 were caused mainly by EV71 and Cox A16, and there were two individual epidemic virus strains. Cox A16 seemed to spread more widely than EV71 in Beijing, 2007.
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 08/2009; 30(8):784-7.
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Chinese medical journal 04/2009; 122(5):584-7. · 0.86 Impact Factor
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ABSTRACT: OBJECTIVE To sequence and analyze the VP1 region of isolated enterovirus from different sources in Beijing, 2006-2008.
9 EV71 were selected from the isolates identified through the specimen of human hand foot mouth disease (HFMD), acute flaccid paralysis (AFP) and healthy children in Beijing, 2006-2008. Reverse transcription-polymerase chain reaction (RT-PCR) method was used to amplify and sequence the whole VP1 gene of enterovirus. Phylogenetic tree was constructed, with the means of nucleotide homology and distance between/within groups analyzed.
The 9 selected strains were clustered with C4 subgenotype reference strains in Phylogenetic tree and showed high nucleotide acid identity (92.1%-93.9% ) in nucleotide homology analysis, and had higher homology than C1, C2, C3 subgenotype reference strains (88.8%-89.5%, 89.4%-90.0% and 88.4%-89.3%, respectively). High homologous (95.9%-100.0%) was noticed between the isolated stains from three different sources, but low homologous (93.3% -93.9%, 92.1%-92.9%, respectively) showed between the isolated stains and C4 reference strains isolated in 1998. There appeared larger variations between groups in C4 subgenotype when analyzing the distance between groups means, especially between the reference strains and isolated strains (D = 0.052-0.071).
The EV71 isolated in Beijing, from 2006 to 2008 also appeared to be C4 subgenotype and there was no significant difference found in the whole sequence of VP1 gene of the strains isolated from different regions, sources, or under different diseases occurred in the same period. There were more nucleotide variations and more chances for the presence of new subgenotype, suggesting that it is necessary to strengthen the surveillance program on EV71 isolates.
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 02/2009; 30(1):45-9.
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ABSTRACT: Analyzing and identifying the type of enterovirus of human Hand Foot Mouth Disease (HFMD) outbreak in Daxing district in Beijing at the end of May in 2007.
The liquid of Herpes, throat swab and stool specimen were collected. Using reverse transcription-polymerase chain reaction (RT-PCR) method to amplify the enterovirus specific nucleotide acid fragment from specimens and virus positive cultures, the sensitivity of two methods was compared. Then identifying and typing of the enterovirus of HFMD through analyzing the results of nucleotide sequencing of the virus positive cultures.
In 10 specimens from 5 HFMD children patients, enterovirus specific nucleotide acid fragment was detected in 8 patients, the RT-PCR positive ratio (80%) was higher than enterovirus isolation positive ratio (30%). In 5 enteroviruses isolated from 5 patients and 9 close contacts, 4 isolated from 2 patients and 1 close contact were Enterovirus 71.1 isolated from close contact was Coxsackievirus A16.
Enterovirus 71 was the pathogen of HFMD outbreak in Daxing district at the end of May in 2007.
Zhongguo ji hua mian yi = Chinese journal of vaccines and immunization 02/2009; 15(1):41-4.
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Chinese medical journal 05/2008; 121(7):664-6. · 0.86 Impact Factor
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Hua-qing Wang,
Xin Guo, Li-juan Chen,
Jie Yang,
Jing-guo He,
Ming Luo,
Xiong He,
Yu-qing Zhou,
Ling-sheng Cao,
Yong Lu,
Da-peng Yin,
Yuan-sheng Chen,
Wei Xia,
Xiao-feng Liang
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ABSTRACT: To investigate the immunity level of diphtheria antibody among children living in the areas where different coverage rates of 4-vaccines stratified by results of national immunization program (NIP) reviewed in 2004.
According to data from 4-vaccine coverage rates of NIP reviewed in 2004, 3 levels could be set. We randomly selected 2 counties at each level and then 10 villages from each county with 42 children involved who were born between 1992 and 2003. ELISA quantitative method was used to test IgG of diphtheria antitoxin.
(1) The positive rate of diphtheria antitoxin was only 49.6% with the highest as 78.1% and lowest as 33.0%. There was a significant decreasing trend of this positive rate with the increase of age. The highest (61.2%) fell in the group that were born in 2003 and the lowest (37.6%) was seen among children born in 1992 to 1995. (2) Geometric mean concentrations (GMCs) was only 0.48 IU/ml with a trend of decrease when age was increasing. There was no GMCs peak seen in children who were at the age of boosting, as expected. (3) Positive rates of children born between 2001 and 2003 were lower than 62% while the diphtheria-pertussis-tetanus (DPT) vaccine coverage rates were all higher than 90%. (4) There was no significant difference of diphtheria antitoxin positive rates between children with eligible routine immunization (58.1%) and those were ineligible (59.6%).
Other than some specific ones, children from most of the investigated counties had a low level of antibody against diphtheria. The coverage rate of DPT vaccine did not necessarily reflect the immunity against diphtheria, suggesting the increase of immunity against diphtheria an urgent task to be taken care of.
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 06/2007; 28(5):433-6.
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ABSTRACT: The aim of this study was to characterize the molecular features of serogroup C Neisseria meningitidis strains circulating in Beijing, China. Twenty out of 23 strains belonged to ST 4821. The causative serosubtype for meningococcal meningitis was P1.12-1,16-8. All of the strains expressed class 3 PorB protein. Among the five pulsed-field gel electrophoresis patterns observed, pattern III predominated.
The Journal of Microbiology 01/2007; 44(6):685-8. · 1.10 Impact Factor
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ABSTRACT: A suspicious meningococcal meningitis death case was reported to the Beijing CDC. The blood specimen was analyzed via multi-PCR and MLST. 6 isolates from close contacts were analyzed via PFGE and MLST. According to the results of the above analyses, the cause of this case was identified as a serogroup A Neisseria meningitidis, which, in terms of sequence typing, belonged the ST7 group.
The Journal of Microbiology 09/2006; 44(4):457-60. · 1.10 Impact Factor
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ABSTRACT: To study the pathogens of meningococcal meningitis (MM) in Beijing, 2005.
Blood and cerebrospinal fluid specimens from MM patients were detected by polymerase chain reaction. Bacterial strains were analyzed by pulsed-field gel electrophoresis and multilocus sequence typing.
7 of the blood and 5 of cerebrospinal fluid specimens showed positive results. 105 of the Neisseria meningitides strains were isolated from the specimens of patients, close contacts and healthy carriers. Serogroup A and C Neisseria meningitides strains shared the same patterns of pulsed-fieldgel electrophoresis, respectively. The sequence type of serogroup A Neisseria meningitides belonged to ST7 while the sequence type of serogroup C Neisseria meningitides belonged to ST4821.
Patients suffered from meningococcal meningitis were caused by serogroup A (ST7) and C (ST4821) Neisseria meningitides in Beijing, 2005.
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 06/2006; 27(5):396-8.
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Xiao-feng Liang,
Yuan-sheng Chen,
Xiao-jun Wang,
Xiong He, Li-juan Chen,
Jun Wang,
Chang-ying Lin,
Hu-qun Bai,
Jun Yan,
Gang Cui,
Jing-jin Yu
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ABSTRACT: To better understand and measure the impact from immunization activities over the last 10-years, we conducted a sero-epidemiological study using the remaining blood samples of a nationwide survey on Nutrition and Health in Chinese residents, in 2002.
HBsAg, anti-HBs and anti-HBc in blood samples were tested using enzyme-linked immunosorbent assay(ELISA) reagents and revised by solid phase radioimmunoassay and Abbott ELISA reagents.
Among population older than 3 years, the prevalence rates of HBsAg, anti-HBs and hepatitis B virus(HBV) infection were 9.09%, 37.48% and 50.04% but for children between 3 and 12 year olds, they were 5.03%, 45.33% and 29.10% respectively. Among population older than 3 years, the rates of HBsAg and HBV infection in urban area were 4.61% and 43.51%, but the rates in rural area were 9.41% and 56.77% respectively while for children from 3-years to 12-years old, they rates were 2.10%, 20.45% in urban area and 8.25%, 39.22% in rural areas, respectively.
Results revealed that since the hepatitis B vaccine was introduced into the expanded program on immunization(EPI) from 1992, the prevalence rates of HBsAg and HBV infection, especially in the children from 3 to 12 years of age, had obviously declined, suggesting that some changes had happened in the epidemic characters of hepatitis B in China.
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 09/2005; 26(9):655-8.
