Application of oral fluid in SARS-CoV-2 nucleic acid and antibody detection / 中华预防医学杂志

This study aimed to explore the application value of new biological specimen oral fluid in SARS-CoV-2 nucleic acid and antibody detection. Oral fluid and paired respiratory and blood specimens from 7 confirmed cases of two COVID-19 cluster epidemic were collected in Beijing from October to November 2021. SARS-CoV-2 virus and IgG antibody were detected by real time PCR kits and serum antibody detection reagents, and SARS-CoV-2 IgG antibody in oral fluids was detected by a new established method of magnetic particle chemiluminescence. The results showed that the nucleic acid amplification test of SARS-CoV-2 on nasopharyngeal swabs, throat swabs and oral fluid specimens from 3 confirmed cases of COVID-19 was positive, among which the Ct value for ORF1a/b and N gene of oral fluid samples in 2 cases was close to that of throat swab, and the Ct value of oral fluid sample for 1 case was higher than that of throat swab. The complete genome sequence of one oral fluid specimen was obtained, which belonged to the VOC/Delta variant strain. The SARS-CoV-2 IgG antibodies of the paired oral fluid and serum were all positive, and the S/CO values of oral fluid were all lower than those of serum. The series of oral fluid results showed that SARS-CoV-2 IgG antibody level increased from 11 to 32 days after the onset of the disease.

Consideration on the emerging of severe acute hepatitis cases with of unknown etiology in children worldwide / 中华预防医学杂志

Since January 2022, severe acute hepatitis cases with unknown etiology in children have occurred in many countries in Europe and the United States, and 43.8% of the cases were positive for human adenovirus (HAdV), and some cases were identified as HAdV-41. However, more evidences including etiology, genomics, liver pathology, and immunohistochemistry are needed to determine the main cause of this outbreak. At present, due to the lack of systematic surveillance and research on hepatitis caused by HAdV infection, it is impossible to determine whether there are similar hepatitis cases occurred in China. It is urgent to carry out HAdV virolgocial surveillance based on clinical symptom, and potential risk of HAdV hepatitis should be studied as soon as possible according to the available relevant clinical, epidemiological and virological data, as well as risk factor information, which will provide scientific and technical support for the prevention and control of HAdV-related diseases.

Advances on molecular typing methods and evolution of human parainfluenza virus / 中华预防医学杂志

Human parainfluenza viruses (HPIVs) is one of the main causes of acute respiratory tract infections in children. HPIVs have been grouped into four serotypes (HPIV1~HPIV4) according to serological and genetic variation. Different serotypes of HPIVs have diverse clinical disease spectrum, epidemic characteristics and disease burden. Based on the nucleotide variation in structural protein genes, HPIVs can be further divided into distinct genotypes and subtypes with diverse temporal and spatial distribution features. The standard molecular typing methods are helpful to clarify the gene evolution and transmission patterns of HPIVs in the process of population transmission. However, the development of molecular epidemiology of HPIVs has been hindered by the lack of a standardized molecular typing method worldwide. Therefore, this study reviewed the viral characteristics, genome structure, existing genotyping methods and evolution of HPIVs, and screened the reference strains for molecular typing, so as to improve the understanding of gene characteristics and molecular typing of HPIVs, and provide an important scientific basis for the monitoring and research of molecular epidemiology of HPIVs in China.

Characterization of human rhinovirus in children with acute respiratory infections in Gansu Province during 2011 / 病毒学报

To study the epidemic characteristics of human rhinovirus (HRV) in children with acute respiratory infections in Gansu Province. 286 throat swabs were collected from children with acute respiratory in fections in Gansu Province during 2011. Multiplex reverse transcription-PCR (multiplex RT-PCR) assay was used to screen those specimens for detection of common respiratory tract pathogens. For HRV-positive samples, nested reverse transcription polymerase chain reaction (nested RT-PCR) was performed to amplify VP1 and VP4/VP2 gene fragments of HRV. The VP4/VP2 and VP1 regions of HRV-positive samples were sequenced and performed genotype analysis. Of 286 specimens fested, 27 were positive for HRV by multiplex RT-PCR and nested RT-PCR, of which 16 children were made (16/185), 8.64%) and 11 female (11/101,10.89%). The positive rate was 9.44% (27/286). The mean age of HRV-positive children was 3 years in this study, children less than one year old had the highest proportion 44.4% (12/ 27, 44.4%). The highest HRV positive rate fell on May, 2011 (6/27, 22.2%). Common cold accounted for the highest proportion, 12.24% (12/98) followed by pneumonia, 8.50% (13/153). The remaining 2 cases were bronchitis. Sequence analysis showed HRV A was the predominant genotype in Gansu Province in 2011, accounting for 84.62% (22/26) of positive cases, followed by HRV C (11.54%, 3/26) and only one HRV B was detected (3.85%, 1/26). HRV could be detected throughout the year in Gansu Province and primarily infected children under one year old. The group A was the epidemic genotype of HRV and move than one genotype existed in Gansu Province during 2011.

Analysis the viral etiology of fever and respiratory tract infection syndrome in Shaanxi province / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>Analysis the viral pathogenic spectrum for patients with fever and respiratory tract infection syndrome in Shaanxi province during 2010 and investigate the molecular epidemiology characteristics of respiratory syncytial virus.</p><p><b>METHODS</b>A total of 208 patients' pharyngeal swabs were collected based on surveillance definition from January 2010 to January 2011 and screened for sixteen human respiratory virus types/subtypes by Qiaxcel-based multiplex reverse transcription-PCR assay, including HRV,HCoV, Flu, HPIV, ADV, HRSV, HMPV and HBoV and investigate molecular epidemiology of HRSV by sequencing and phylogenetic analysis of the C-terminal second hypervariable region of the G gene.</p><p><b>RESULTS</b>109 out of 208 specimens (53%) were positive for one or more viruses. HRSV(42. 2%) was the dominant pathogen detected, followed by Flu(24. 5%), PIV(20%), HRV(13.6%) and ADV( 10.9%),there were also 8 strains of HCoV, 5 strains of HMPV and 3 strains of HBoV detected. The results showed that 22 specimens were positive for two or more viruses, PIV (14/22) was the most frequently detected viral agent among co-infection specimens, and the highest incidence of mixed infection is aged 15-39 years group (P < 0.05). The overall viral detection rate was no related to age. In addition to Flu, HMPV and PIV, other viruses (HRV, HBoV, HCoV, ADV, RSV) mainly infected 0 to 4 years old children. Among 46 HRSV positive specimens, 42 HRSV-A strains clustered into NA1 genotype and two HRSV-B strains clustered into two genotypes, BA9 and GB2.</p><p><b>CONCLUSION</b>HRSV is the dominate pathogen collected from patients with fever and respiratory tract infection syndrome in Shaanxi and HRSV A is the predominant subtype. For most viruses, infection was most prevalent among children aged <4 years. PIV was the most common pathogen in co-infection.</p>

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>

Transmission and prevalence patterns of C4a evolutionary lineage of human enterovirus 71 circulating in mainland China, 2008-2010 / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To understand the evolutionary relationship between the C4a evolutionary lineage of human enterovirus 71 (HEV71) strains circulating in mainland of China during 2008-2010 and 2008 Fuyang strains and study the prevalence and transmission patterns of 2008 Fuyang strains.</p><p><b>METHODS</b>Download all the complete VP1 ( > or = 891 bp) or approximate complete VP1 (> or = 876 bp) gene nucleotide sequences from GenBank of HEV71 strains circulating in Mainland of China during 2008-2010. And analyze the phylogenetic relationship between Fuyang strains and other provinces' strains using the MEGA software, version 5.0.</p><p><b>RESULTS</b>All of the HEV71 isolates circulating in Mainland of China during 2008-2010 were clustered into evolutionary lineage C4a except for eight strains grouped in the genotype A and one isolate belongs to evolutionary lineage C4b; the homology analysis showed there were 96.5%-100% identity between C4a viruses circulating in mainland China during 2008-2010 and 2008 Fuyang strains, and they were evolved from C4b viruses of 1998. The transmission chains of Fuyang strains were mainly transmitted in Guangdong, Jiangsu, Shanghai, Hunan, Shandong provinces.</p><p><b>CONCLUSION</b>The predominant viruses circulating in Mainland of China during 2008-2010 were evolutionary lineage C4a of human Enterovirus 71; Fuyang transmission chains mainly distributed in southern of China and the Central China around Anhui provinces.</p>

A GeXP based multiplex RT-PCR assay for simultaneous detection of twelve human respiratory viruses / 病毒学报

A GeXP based multiplex RT-PCR assay was developed to simultaneously detect twelve different respiratory viruses types/subtypes including influenza A virus, influenza B virus, influenza A virus sH1N1, parainfluenza virus type 1, parainfluenza virus type 2, parainfluenza virus type 3, human rhinovirus, human metapneumovirus, adenovirus, respiratory syncytial virus A, respiratory syncytial virus B and human bocavirus. Twelve sets of specific primers were designed based on the conserved sequences of available respiratory-virus sequence database. The specificity of the multiplex system was examined by positive specimens confirmed previously. The sensitivity to detect twelve respiratory viruses simultaneously was 10(3) copies/microL. Twenty four clinical specimens were further detected by this novel assay and the results were compared with that of the real-time RT-PCR. These results showed that this novel assay based on GeXP is a fast, sensitive, and high throughput test for the detection of respiratory virus infections.

The study of human rhinovirus in infants with lower respiratory tract infections / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>We want to explore the harm degree of human rhinovirus in infants in Beijing area.</p><p><b>METHODS</b>From May 2008 to September 2009, 240 nasopharyngeal aspirates were collected from the children and infants who were hospitalized and with lower respiratory tract infections. These specimens were screened for HRV by real-time reverse transcription PCR (RT-PCR) and statistically analysised.</p><p><b>RESULT</b>In all of 240 hospitalized children, 208 cases were admission diagnosis of pneumonia, accounting for 86.67% (208/240), no deaths, the ratio of male and female patients was 1.93 : 1, and the collected samples reached to a maximum number in February 2009. Real-time PCR used to detect human rhinovirus, positive samples number is 71, positive rate is 29.58% (71/240), and the main symptoms and clinical diagnosis was pneumonia. Most cases were less than 2 years old, making up 81.69% (58/71), amony them, 13 months-18 months age and > or = 24 months groups have the highest incidence rates, the incidence rate is 33.33%.</p><p><b>CONCLUSION</b>Human rhinovirus happened in spring and winter seasons, especially the infants who were under 2 years are the main infection groups, the important symptoms are lower respiratory infections such as pneumonia, bronchitis and bronchiolitis et al. Human rhinovirus is seasonal and contagious, spreads fast, so protective measures in hospitals should be prepared to avoid cross-infection.</p>

Genetic characterization of measles virus caused the measles outbreak in Xinjiang / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To analyze the genetic characterizations of wild type measles viruses caused the measles outbreak in Xinjiang.</p><p><b>METHODS</b>Vero/Slam cell were used for measles viruses isolation from the specimens collected from measles outbreaks patients. Fragment of 676 nucleotide acids of the carboxylend of nucleoprotein gene were amplified using reverse transcription-polymerase chain reaction (RT-PCR) method and then the PCR products were directly sequenced and analyzed. Phylogenetic tree was constructed based on 450 nucleotide acids of the N-terminus of nucleoprotein gene, and homological analysis was performed at nucleotide acid level.</p><p><b>RESULTS</b>11 measles viruses were sequenced and all belonged to H1a subgenotype. The nucleotide difference was 0-0.2% between 11 Xinjiang isolates. And the nucleotide difference was 2.2%-2.4% between Xinjiang isolates and H1 genotype reference strain.</p><p><b>CONCLUSION</b>The Measles viruses causing the measles outbreak in Xinjiang were H1a subgenotype.</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>

Genetic characterization of Chinese rubella virus isolates from 2003 to 2007 / 病毒学报

57 rubella virus strains were isolated using Vero cell line or Vero/SLAM cell line from patients' throat swabs during rubella outbreaks and sporadics in 10 provinces of China from 2003 to 2007. Fragments of 1107 nucleotides of E1 genes of the isolates were amplified by RT-PCR, the PCR products were directly sequenced and analyzed. The phylogenetic analysis based on 739 nucleotides showed that out of 57 Chinese rubella virus strains, 55 belong to a distinguish branch of 1E genotype when comparing with 1E genotype rubella strains from other countries, and the other 2 Chinese rubella virus strains belong to 2B genotype. Most of the nucleotide mutations of 57 rubella viruses were silent mutations, and the amino acid sequences were highly conserved. Except one amino acid change (Thr212 --> Ser212) in two rubella viruses at the hemagglutination inhibition and neutralization epitopes, there had no change found at the important antigenic epitope sites of the other rubella viruses. 1E genotype rubella viruses isolated from 10 provinces of China from 2003 to 2007, and two imported 2B genotype rubella viruses from Vietnam suggested that 1E genotype was the predominant genotype in this period of time. The rubella virus genotypes circulated during 2003 to 2007 were different from that circulating during 1979 to 1984 and 1999 to 2002, the rubella prevailed in recent years was mainly caused by 1E genotype rubella viruses with multi-transmission routes.

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>

A serological survey of Epstein-Barr virus infection in children in Beijing / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To understand the prevalence of Epstein-Barr virus (EBV) infection in urban and rural areas of Beijing using the serological method.</p><p><b>METHODS</b>Totally 589 serum samples were collected from children in Beijing urban and rural areas who were 0--14 years old and tested with Viron-Seron ELISA classic EBV virus capsid antigen IgG antibody (EBV VCA IgG) kit. Optical density of serum samples was obtained at the wavelength of 405 nanometers. Sero-positive or negative samples were determined according to standard curve and cut-off attached in ELISA classic EBV VCA IgG kits. The activity of EBV VCA IgG was calculated by using special formula. The percentage and activity of EBV VCA IgG from Beijing children were compared with SPSS 13.0 between the urban and rural areas.</p><p><b>RESULTS</b>The percentage of EBV VCA IgG seropositive samples was 83.6%, and 80.8% in those from urban and 86.2% in those from rural areas. The peak value of EBV infection was 71% seen among children under the age of 3 years, and in urban area the rate was 67.7%, which was lower than that in the rural area (75.3%), and was 82.5% by the age of 6, which was lower than the data (up to 90%) reported 30 years ago. There was a significant difference in EBV infection rate and VCA IgG activities in children at different ages between urban and rural areas (P < 0.05).</p><p><b>CONCLUSION</b>The rate of EBV infection in children living in urban area was lower by the age of 6 years. The primary infection of EBV occurred late in part of children lived in urban area.</p>