The Genomic Characterization of Enterovirus D68 from 2011 to 2015 in Beijing, China / 生物医学与环境科学（英文）

A retrospective surveillance study on enterovirus D68 was performed in Beijing, China, following the largest and most widespread EV-D68 infection, which occurred in the USA. From January 2011 to July 2015, EV-D68 was identified in 12 individuals with respiratory infections in Beijing, China. The phylogenetic relationships based on the genomic sequence alignment showed that there were two lineages circulating in Beijing from 2011 to 2015. Eight EV-D68 strains belonged to group 1 and four belonged to group 3. All EV-D68 strains from Beijing in 2014 were separately clustered into subgroup II of group 1. Based on these results, we concluded that the Beijing EV-D68 strains had little association with the EV-D68 strains circulating in the 2014 USA outbreak.

Rapid identification of Beijing measles vaccine virus and wild virus by multiplex real-time fluorescent PCR / 中华预防医学杂志

<p><b>OBJECTIVE</b>To identify wild measles virus and vaccine virus by detection nucleic acid of clinical samples from measles patients with immunization history circulating in Beijing through multiplex real-time fluorescent PCR technology.</p><p><b>METHODS</b>From July 2011 to February 2012, 10 throat swabs and 15 urine specimens were collected from 16 suspected measles patients who were 8 - 9 months old infants with immunization history in Beijing. The specificity of multiplex real-time fluorescent PCR was firstly tested by measles vaccine virus, wild virus and other respiratory virus. Then the vaccine virus and wild virus were titrated and diluted to test the sensitivity of the PCR method. The result was then compared with it analyzed by PCR-RFLP method. Meanwhile, the clinical sample of the measles patients were tested and confirmed by sequencing method.</p><p><b>RESULTS</b>The primer-probe sets of Fam, Joe and Cy5 showed great specificity of measles virus, and could distinguish the measles vaccine virus and wild virus well. The sensitivity of this method to detect measles vaccine virus reached 0.1 CCID(50)/0.1 ml; and the sensitivity to wild virus reached 0.006 CCID(50)/0.1 ml; which were both higher than the sensitivity of PCR-RFLP method. Out of the 16 measles patients with vaccination history, 3 were negative and the other 13 all belonged to measles virus genotype A, and were confirmed to be vaccine virus by sequencing method.</p><p><b>CONCLUSION</b>Multiplex real-time PCR method is accurate, rapid and sensitive to identify measles vaccine virus and wild virus. The method could greatly help us to find measles patients and to identify the vaccine-related cases.</p>

Study on the Fast Testing Strategy for identifying the wild poliovirus Ⅰ / 中华流行病学杂志

Objective To explore the Fast Testing Sstrategy (FTS) for wild poliovirus Ⅰ (WP1).Methods 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 WPV I.Results ( 1 ) 33 non-poliovirus enterovirus (NPEV) cases were detected,with 16 polio vaccinerelated 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 WPV 1 cases were also detected in this study and confirmed by GNPL.(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-housc 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 higher than that of the RT-PCR assay.Conclusion The novel FTS for WPV I 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.

Study on the prevalence of acute flaccid paralysis and hand foot mouth disease in Beijing 2006-2008 / 中华流行病学杂志

Objective To study the prevalence of acute flaccid paralysis(AFP)and hand foot mouth disease(HFMD)in Beijing,from 2006-2008.Methods Data on AFP and HFMD was analyzed epidemiologically,during 2006-2008 in Beijing.All the specimens from AFP cases were isolated and identified by RD and L20B cell and all of non-polio enterovirus(NPEV)cases were assayed by HFMD real-time PCR kit.The relationship between AFP and HFMD was analyzed.Results During 2006-2008,the number of AFP case in Beijing increased from 108 to 177 while the NPEV isolation rate increased from 11.11%to 20.34%and the positive rate of enterovirus 71(EV71)and/or coxsackie virus A16(Cox A16)increased from 0.93%to 10.17%.Conclusion The prevalence of HFMD caused by EV71 and/or Cox A16 might have contributed to the increase of AFP cases in Beijing.

Comparison of genotype characteristics between the circulating mumps virus strain in Beijing area and the vaccine strain / 中华流行病学杂志

Objective To compare the genetic characteristics of mumps virus strain circulating in Beijing with vaccine strain and to preliminarily analysis the reasons of vaccine ineffectiveness. Methods 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. Results 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 IgMdecreased 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. Conclusion 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.

Molecular typing of Neisseria meningitidis serogroup C strains with pulsed field gel electrophoresis in China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the characteristics of epidemiology and molecular typing on Neisseria meningitidis serogroup C strains associated with outbreaks of Anhui province and sporadic cases in China, using pulsed field gel electrophoresis (PFGE).</p><p><b>METHODS</b>212 Neisseria meningitidis serogroup C strains were isolated from invasive meningococcal cases, close contacts and healthy carriers, including 48 strains from Anhui province with 38 strains associated with serogroup C outbreaks. PFGE were performed by genomic DNA digestion with Nhe I restriction enzyme. The results of PFGE were analyzed by BioNumerics software (Version 4.0, Applied Maths BVBA, Belgium).</p><p><b>RESULTS</b>A total number of 212 Neisseria meningitidis serogroup C isolates were typed by 43 patterns, named AH1 to AH43. In China, AH1 pattern was the major PFGE pattern with 69.3% (n = 147) of all strains, distributed in 11 provinces. Three types of PFGE patterns (AH1 to AH3) were found in 48 strains from Anhui province, in which, 93.8% (n = 45) belonged to AH1. 97.4% (n = 37) of 38 strains associated with serogroup C outbreaks in Anhui province showed AH1 pattern. A total of 53 serogroup C strains were isolated from invasive meningococcal cases with 67.9% (36/53) of AH pattern. 71.9% (87/121) of serogroup C strains isolated from contacts of invasive meningococcal cases was AH1 pattern and 63.2% (24/38) of the strains from healthy carriers showed AH1 pattern.</p><p><b>CONCLUSION</b>By PFGE typing and analysis, AH1 pattern of Neisseria meningitidis serogroup C strains was proved to be the main clone which causing the outbreaks in Anhui province and might be responsible for the sporadic serogroup C meningococcal disease epidemics else where in the country.</p>

Surveillance on pathogens of meningococcal meningitis in Beijing, 2005 / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the pathogens of meningococcal meningitis (MM) in Beijing, 2005.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSION</b>Patients suffered from meningococcal meningitis were caused by serogroup A (ST7) and C (ST4821) Neisseria meningitides in Beijing, 2005.</p>