Genetic characterization of human parainfluenza virus 3 circulating in Gansu and Shaanxi Provinces from 2009 to 2011 / 病毒学报

To investigate the genetic characterization of Human parainfluenza virus-3 (HPIV-3) circulating in Gansu and Shaanxi Provinces of China, 719 throat swabs were collected from pediatric patients with acute respiratory infections from 2009-2011. Multiplex RT-PCR was used to screen common respiratory viral pathogens. For HPIV-3-positive specimens, nested RT-PCR was used to amplify the HN gene of HPIV-3. The nucleotides of Hemagglutinin-neuraminidase(HN)gene of 13 HPIV-3 positive strains identified in Gansu and Shaanxi Provinces were successfully sequenced and compared with those downloaded from GenBank. The phylogenetic analysis based on the nucleotides sequence of HN gene showed that 13 HPIV-3 strains belonged to sub-cluster C3 with little sequence variation (overall nucleotide divergence of 0.2%-2.3% and amino acid divergence at 0-1.1%). Compared with the complete gene of HPIV-3 strains from U.S.A., Canada, and Australia, the biggest divergence of the nucleotide and amino acid lovels was 6.0% and 3.4%, respectively. The nucleotide divergence between shaanxi09-2 and shaanxi10-H0091 was 0.9%, while the nucleotide divergence between shaanxi10-H005 and gansull-62110372 was 0.5%, between shaanxi09-2 and BJ/291/09 was 0.6%. However, there was no amino acid divergence among them. It is likely that HPIV-3 virus had been transmitting in Gansu and Shaanxi Provinces for several years. Human parainfluenza virus-3 (HPIV-3) circulated in Gansu and Shaanxi Provinces from 2009 to 2011 belonged to sub-cluster C3.

Simultaneous detection of human parainfluenza viruses 1, 2, 3 by multiplex real-time reverse transcription-polymerase chain reaction with LNA probes / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>Human parainfluenza virus (HPIV) types 1, 2 and 3 are major viral pathogens responsible for upper and lower respiratory tract infections. In this study, a real-time RT-PCR was developed using multiplex primers-probe (HPIV-1, 2, 3) for the simultaneous detection of both HPIV1, HPIV2 and HPIV3 genomes.</p><p><b>METHODS</b>Optimal primers and probes were designed using specialized software. The conditions for multiplex real-time RT-PCR had been optimized. The synthesis of RNA standards of HPIV1, 2, 3 were used a T7 RNA polymerase. Check the specificity sensitivities and stability of one step RT-PCR assay.</p><p><b>RESULTS</b>Obtained in a 10-fold dilution series assay demonstrate a high sensitivity of the assay with a lowest detection limit of 10 copies for HPIV1, 100 copies for HPIV2 and 100 copies for HPIV3.</p><p><b>CONCLUSION</b>The assays demonstrates an improved sensitivity and scope of detecting HPIV1, 2, 3 viruses relative to routine antigen detection assays while the quantitative utility may facilitate investigation of the pre-diagnosis and respiratory virus pathogenesis.</p>

Seroepidemical study of Coxsackievirus A 16, in four provinces, China, 2005 / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To study the situation of 1- 5-years-old children's antibody against Coxsackievirus A group 16 strain (CVA16) in Guangdong, Heilongjiang,Yunnan Province and Xinjiang Uygur Autonomous Regions, China, 2005, it can offer scientific evidences for preventing and controlling CVA16 causative hand-food and mouth disease.</p><p><b>METHODS</b>Using microneutrilization test, to study 503 serum samples randomly selected from sera collected in 2005.</p><p><b>RESULTS</b>Positive rate of anti-CVA16 antibody were 41.90%, 9.40%, 40.00% and 34.40% in Guangdong, Heilongjiang,Yunnan and Xinjiang, respectively. Antibody titer was relative low (average, 1: 6.1) and there was no statistical difference of geometry mean of antibody titer (GMT) among Guangdong, Heilongjiang, Yunnan (F = 0.97, 0.40, 1.06, respectively; P > 0.05), while there had statistical difference of GMT between Heilongjiang and other three regions( F = 10.61, P < 0.00).</p><p><b>CONCLUSIONS</b>There had probably existed local epidemic in some regions of Guangdong, Heilongjiang, Yunnan Province and Xinjiang Uygur Autonomous Regions, China, 2005 or even before, but the area and degree of transmission and epidemic had difference. Children aged from 1- 5-years-old were relatively susceptible population of CVA16 infection.</p>

Application of a simple method for the detection of measles virus genome by loop-mediated isothermal amplification (LAMP) / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>A new simple RT-LAMP method was applied to detect measles virus nucleic acid and compared with nest-RT-PCR.</p><p><b>METHODS</b>Compare the detection rate of the RT-LAMP method with that of nest-RT-PCR by detecting measles virus nucleic acid from measles virus and clinical samples.</p><p><b>RESULTS</b>The nucleic acid positive rates of all 23 strains of measles virus are all 100% by the two methods. But to the detection of 18 clinical samples which are negative in measles isolation, the nest-RT-LAMP showed 56.52% positive rate of nucleic acid of measles virus and nest-RT-PCR showed 47.83%.</p><p><b>CONCLUSION</b>RT-LAMP is more sensitive than nest-RT-PCR.</p>

Measles pathogenic surveillance from 2005 to 2007 in Guangdong Province / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To develop pathogenic surveillance on measles and to effectively isolate measles virus. To know the genetic characterizations and molecular epidemiology of wildtype measles viruses from 2005 to 2007 in Guangdong Province, and provide the scientific basis for measles control and eradication.</p><p><b>METHODS</b>Vero/Slam cell line were used, measles viruses were isolated from throat swabs or urine specimens collected from uspected measles patients in outbreaks and sporadic patients. A 450 nucleotides fragment of the C-terminal of the nucleoprotein (N) gene was amplified and by RT-PCR and subjected to sequence and phylogenetic analysis using Bio-Edit software.</p><p><b>RESULTS</b>82 wild-type measels virus were obtained from 377 throat swabs and urine specimens from 2005 to 2007 in Guangdong Province measles lab. The measles isolation rate was 23.58% in 2005, 17.11% in 2006, 39.13% in 2007. The succeed rate of virus isolation is related to the quality of specimens collected and the days after rash occurrence.</p><p><b>CONCLUSIONS</b>We have grasped the technicalability of measles virus isolation and confirm action, and got higher isolation ratio. The wild-type measles virus isolated from Guangdong Province is of H1 genotype from 2005 to 2007, which is the same as the dominant genotype circulation.</p>

Genotype and gene charactrization of wild-type measles viruses circulated in Jilin Province / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To study the genotype and gene characterization of measles wild viruses circulated in Jilin provinces, and to provide scientific evidences for setting down controlling and preventing strategy and measures.</p><p><b>METHODS</b>38 strains of measles virus isolated in 2001-2006 were genotyped by RT-PCR-RFLP, some strains of measles virus in Jilin province were chosen for the phylogenetic analysis and for the homology analysis of nucleotide and amino acid sequences.</p><p><b>RESULTS</b>All the 38 strains of measles virus were identified as H1 genotype by RT-PCR-RFLP, and 29 strains of them were identified further as H1 a by sequence analysis. The homology of nucleotide was 88.0%-89.4% and the homology of amino acid was 91.8%-92.7% .The average diversity was less than 1.4%.</p><p><b>CONCLUSION</b>The measles virus of H1a genotype was the circulating virus within recent years in Jilin province. There were the same measles virus strains circulating and transmitting at different years and also the different H1a measles virus strains co-circulating at the same year. There were the same transmission chain caused by the same measles virus with other provinces.</p>

Human bocavirus in children suffering from acute lower respiratory tract infection in Beijing Children's Hospital / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Human bocavirus (HBoV) is a parvovirus recently found to possibly cause respiratory tract disease in children and adults. This study investigated HBoV infection and its clinical characteristics in children younger than five years of age suffering from acute lower respiratory tract infection in Beijing Children's Hospital.</p><p><b>METHODS</b>Nasopharyngeal aspirates were collected from children suffering from acute lower respiratory tract infection during the winters of 2004 to 2006 (from November through the following February). HBoV was detected by polymerase chain reaction amplification and virus isolation and the amplification products were sequenced for identification.</p><p><b>RESULTS</b>HBoV infection was detected in 16 of 333 study subjects. Coinfections with respiratory syncytial virus were detected in 3 of 16 HBoV positive patients with acute lower respiratory tract infection. The median age for HBoV positive children was 8 months (mean age, 17 months; range, 3 to 57 months). Among the HBoV positive children, 14 were younger than 3 years old, 9 were younger than 1 year old and 7 were younger than 6 months. These 16 positive HBoV children exhibited coughing and abnormal chest radiography findings and more than 60% of these children had wheezing and fever. Ten children were clinically diagnosed with pneumonia, 2 bronchiolitis, 2 acute bronchitis and 2 asthma. One child died.</p><p><b>CONCLUSIONS</b>HBoV was detected in about 5% of children with acute lower respiratory infection seen in Beijing Children's Hospital. Further investigations regarding clinical and epidemiologic characteristics of HBoV infection are needed.</p>

Genotype of wild-type measles viruses circulating in Beijing in 2003 / 中华儿科杂志

<p><b>OBJECTIVE</b>To investigate genotype of wild-type measles viruses circulated in Beijing in 2003.</p><p><b>METHODS</b>Throat swabs specimens were collected from patients seen during an outbreak of measles and from clinically suspected sporadic measles patients in 2003. Vero/SLAM cell lines recommended by WHO were used to isolate measles virus. Four hundreds and fifty nucleotides of COOH-terminal of nucleoprotein (N) genes were amplified by using PR-PCR. The amplified products were sequenced and the sequences were compared with references viruses from GeneBank.</p><p><b>RESULTS</b>Eight strains of measles viruses were isolated from throat swabs of patients who came from seven districts and counties of Beijing. Sequence analysis of the 450 nucleotides of COOH-terminal of nucleoprotein (N) genes indicated that these 8 strains belonged to H1a genotype. The average genetic distances of these 8 strains to H1a genotype, Chin9322, H1b genotype, Chin9475 and H1c genotype, Chin9427, were 0.004 - 0.011, 0.026 - 0.031 and 0.015 - 0.022, respectively. The average genetic distances of these 8 strains to H1a genotype, Anhui 01 - 1/Anhui 02 - 2, were 0.000 - 0.009 (0 - 5 nucleotide variation).</p><p><b>CONCLUSIONS</b>Major genotypes of wild-type measles viruses circulated in Beijing in 2003 were H1a genotype. The genotypes H1c, H1b and H2 may have disappeared in Beijing.</p>