To understand the role of respiratory syncytial virus (RSV) in children with acute respiratory infections (ARI) in Tibet Autonomous Region and the contribution of two major groups of RSV, nasopharyngeal aspirates (NPA) were collected from hospitalized children with ARI in Department of Pediatrics, Tibet People's Hospital in Lasa, Tibet from April to July in 2011 and tested for seven common respiratory viruses and human metapneumovirus (hMPV) by direct immunofluorescence assay (DFA). Total RNAs were extracted from RSV positive samples by DFA and reverse transcripted to cDNA. Nested-PCR was employed to determine the genogroups of RSV, which were confirmed by real time-PCR and sequence analysis for G protein encoding gene. The Characteristics and variations of G genes from RSV in this project were identified by sequence comparison with those G genes in GenBank. Out of 167 samples, 65 were positive for respiratory viruses with a total positive rate of 38.9%, including 45 (69.2%, 45/65)positive samples for RSV. Among 42 samples that were positive for RSV and genotyped, 40 were identified as group A and 2 as group B. Sequence analysis of full-length G genes for 7 RSV of group A indicated that all of these belonged to subgroup GA2. The nucleotide identities between RSVs from Tibet and prototype A2 strain were 90.7%-91.8%, with 86.5%-87.2% identities of amino acid. The mutations of amino acids were mainly located in both ends of a highly conserved region in the ectodomain of the G proteins. The data indicated that RSV was the most important viral etiologic agent of ARI in spring of 2011 in Tibet and group A of RSV was predominant during the study period. High divergence existed in the ectodomain of G proteins of RSVs from Tibet.
Acute Disease ; Amino Acid Sequence ; Female ; Humans ; Infant ; Male ; Molecular Sequence Data ; Phylogeny ; Respiratory Syncytial Virus Infections ; virology ; Respiratory Syncytial Viruses ; chemistry ; classification ; genetics ; isolation & purification ; Respiratory Tract Infections ; virology ; Sequence Alignment ; Tibet ; Viral Proteins ; chemistry ; genetics

PURPOSE: Early identification of causative agents in lower respiratory infection of pediatric patients can reduce morbidity and prevent an overuse of antimicrobials. Two kinds of multiplex polymerase chain reaction (PCR) and a commercial shell vial viral culture were performed to identify causative agents in pediatric patients. MATERIALS AND METHODS: Nasopharyngeal aspirates of 220 children diagnosed with viral pneumonia were obtained. Two kinds of multiplex PCR (Seeplextrade mark RV detection kit, and Labopasstrade mark RV detection kit), and a shell vial culture by R-Mix were performed. RESULTS: Positive samples from 220 total samples by two multiplex PCRs were 52.7% and 46.4%, respectively. We also cultured 103 samples that showed positive results of the adenovirus, influenza virus, parainfluenza virus, and respiratory syncytial virus (RSV) by two multiplex PCR. The RSV was most frequently detected in 53.0% (Seeplex) and 51.7% (Labopass) of patients. The detection rate of adenovirus (AdV) was 10.3% and 12.1%, influenza virus (IFV) A and B was 12.5% and 3.4%, and parainfluenza virus (PIFV) 1, 2, and 3 were 2.9% and 2.6%. Shell vial cultures showed concordant results with each multiplex PCR by 96.1% and 77.7%, respectively. Sequencing results were 90% consistent with multiplex PCR. CONCLUSION: Multiplex PCR showed more positivity than the shell vial culture and it can be an effective primary test. Other complementary efforts such as viral cultures and sequencing analysis could be considered, according to clinical and laboratory conditions.
Adenoviridae/genetics/*isolation & purification ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Orthomyxoviridae/genetics/*isolation & purification ; Pneumonia, Viral/*virology ; Polymerase Chain Reaction/*methods ; Respiratory Syncytial Viruses/genetics/*isolation & purification ; Respirovirus/genetics/*isolation & purification

OBJECTIVETo understand the clinical characteristics and outcome associated with respiratory syncytial virus (RSV) infection in hematopoietic stem cell transplantation (HSCT) recipients with primary immunodeficiencies (PIDs).

METHODNasopharyngeal aspirate samples were collected consecutively before and after HSCT from 9 recipients from Apr. 2009 to Sep. 2010 and analyzed for the presence of RSV using real-time polymerase chain reaction assay. To further verify the presence of the virus, positive samples for PCR were isolated for RSV. RSV G gene was amplified, sequenced and used for phylogenetic analysis.

RESULTThe presence of RSV was detected in 3 out of 9 children. The viral replication in all the patients was prolonged for months. All the 3 patients with RSV infection were treated with intravenous immune globulin (IVIG) and one was treated with antiviral medication. All patients survived and achieved successful immune reconstitution.

CONCLUSIONThis study indicates that the HSCT recipients with PID are at increased risk for RSV infection. RSV can shed for months after the initial infection and the patients recover with the course of immune reconstitution.

Child, Preschool ; Female ; Hematopoietic Stem Cell Transplantation ; adverse effects ; Humans ; Immunologic Deficiency Syndromes ; surgery ; virology ; Infant ; Prognosis ; Respiratory Syncytial Virus Infections ; diagnosis ; drug therapy ; Respiratory Syncytial Viruses ; genetics ; isolation & purification ; physiology ; Virus Replication ; Virus Shedding

Child ; Child, Preschool ; Computer Systems ; Humans ; Phylogeny ; Polymerase Chain Reaction ; methods ; Respiratory Syncytial Viruses ; genetics ; isolation & purification ; Reverse Transcriptase Polymerase Chain Reaction ; methods

OBJECTIVEThe present study was designed to explore the practical application of the rapid etiological diagnosis by detecting specific IgM antibody against common respiratory viruses in children with acute lower respiratory infections (ALRI).

METHODClinical specimens including nasopharyngeal aspirates and serum of acute phase from hospitalized children were collected from 207 infants and children with acute lower respiratory infections from March 2009 to September 2010. Seven common respiratory virus antigens were identified from the collected nasopharyngeal aspirates by direct immunofluorescence assay (DFA). ELISA was used to detect specific IgM antibody against RSV, ADV, IFVA, IFVB and PIV, while indirect immunofluorescence assay (IFA) was used to detect specific IgM antibody against RSV, ADV, IFVA, IFVB, PIV1, PIV2 and PIV3 in collected acute phase serum.

RESULTThe overall positive rates to detect viral antigen by using DFA, ELISA and IFA was 67.6%, 57.5% and 39.6%, respectively. The consistent rate of ELISA and IFA versus accepted DFA were 21.7% and 31.4%, respectively. The average days from onset of the symptoms to blood sample collection for those with the consistent results by ELISA and DFA were 12.0 d for ADV, 9.6 d for PIV2, 9.5 d for IFV, and 5.3 d for RSV, respectively, and by IFA and DFA were 15.0 d for PIV3, 9.2 d for ADV, and 7.4 d for RSV, respectively. Among all age groups, the consistent rate of serum viral IgM and antigen detections was highest in children younger than 3 years old.

CONCLUSIONAlthough there were differences between serum IgM antibody and viral antigen detections, specific IgM antibody detection was of value in early and rapid etiological diagnosis of pediatric ALRI, especially for young children. It could provide serologic evidence of respiratory virus infection. The diagnostic rate of pathogen could be improved if it was used in combination with viral antigen diagnostic methods.

Antibodies, Viral ; analysis ; blood ; Antibody Specificity ; Antigens, Viral ; analysis ; Child ; Child, Preschool ; Enzyme-Linked Immunosorbent Assay ; Female ; Fluorescent Antibody Technique ; Humans ; Immunoglobulin M ; analysis ; blood ; Infant ; Male ; Nasopharynx ; virology ; RNA Viruses ; genetics ; isolation & purification ; Respiratory Syncytial Virus Infections ; diagnosis ; virology ; Respiratory Syncytial Viruses ; genetics ; isolation & purification ; Respiratory Tract Infections ; diagnosis ; immunology ; virology ; Sensitivity and Specificity

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.
Humans ; Influenza A Virus, H1N1 Subtype ; genetics ; isolation & purification ; Orthomyxoviridae ; genetics ; isolation & purification ; Orthomyxoviridae Infections ; virology ; RNA Viruses ; genetics ; isolation & purification ; Real-Time Polymerase Chain Reaction ; instrumentation ; methods ; Respiratory Syncytial Viruses ; genetics ; isolation & purification ; Respiratory Tract Infections ; virology ; Reverse Transcriptase Polymerase Chain Reaction ; instrumentation ; methods ; Rhinovirus ; genetics ; isolation & purification ; Sensitivity and Specificity

This study was performed to characterize respiratory viral infections in pediatric patients undergoing hematopoietic stem cell transplantation (HSCT). Study samples included 402 respiratory specimens obtained from 358 clinical episodes that occurred in the 116 children of the 175 consecutive HSCT cohort at Seoul National University Children's Hospital, Korea from 2007 to 2010. Multiplex reverse-transcription polymerase chain reactions were performed for rhinovirus, respiratory syncytial virus (RSV), parainfluenza viruses (PIVs), adenovirus, human coronavirus (hCoV), influenza viruses and human metapneumovirus. Viruses were identified in 89 clinical episodes that occurred in 58 patients. Among the 89 clinical episodes, frequently detected viruses were rhinovirus in 25 (28.1%), RSV in 23 (25.8%), PIV-3 in 16 (18.0%), adenovirus in 12 (13.5%), and hCoV in 10 (11.2%). Lower respiratory tract infections were diagnosed in 34 (38.2%). Neutropenia was present in 24 (27.0%) episodes and lymphopenia was in 31 (34.8%) episodes. Sixty-three percent of the clinical episodes were hospital-acquired. Three patients died of respiratory failure caused by respiratory viral infections. Respiratory viral infections in pediatric patients who have undergone HSCT are common and are frequently acquired during hospitalization. Continuous monitoring is required to determine the role of respiratory viruses in immunocompromised children and the importance of preventive strategies.
Adenoviridae/genetics/isolation & purification ; Adolescent ; Adult ; Child ; Child, Preschool ; Cohort Studies ; Coronavirus/genetics/isolation & purification ; Female ; *Hematopoietic Stem Cell Transplantation ; Hematopoietic Stem Cells/cytology ; Hospitalization ; Humans ; Infant ; Lymphopenia/epidemiology ; Male ; Neutropenia/epidemiology ; Parainfluenza Virus 3, Human/genetics/isolation & purification ; Prevalence ; Respiratory Syncytial Viruses/genetics/isolation & purification ; Respiratory Tract Infections/epidemiology/therapy/*virology ; Reverse Transcriptase Polymerase Chain Reaction ; Rhinovirus/genetics/isolation & purification ; Seasons ; Young Adult

OBJECTIVETo establish a convenient and high-throughput respiratory virus detection method to facilitate epidemiological viral monitoring.

METHODSWe used high-throughput microsphere-based flexible multi-analyte profiling technology (xMAP) coupled with signal amplification molecules to simultaneously detect RNAs of 8 viruses including influenza viruses A and B, parainfluenza viruses type 1, 2 and 3, respiratory syncytial viruses A and B, and metapneumovirus in a 96-well plate format. The sensitivity and specificity of the method for the synthetic viral RNAs were evaluated.

RESULTSThere was no cross-reactivity among the 8 respiratory viral target RNAs. The detection limits for the 8 viral in intro-transcribed RNAs ranged from 1204 to 4695 RNA copies.

CONCLUSIONWe establish a sensitive, specific, convenient, and high-throughput multiplex detection method suitable for detecting multiple respiratory viral RNAs for epidemiological viral monitoring.

High-Throughput Screening Assays ; methods ; Influenza A virus ; genetics ; isolation & purification ; Influenza B virus ; genetics ; isolation & purification ; Limit of Detection ; Metapneumovirus ; genetics ; isolation & purification ; Nucleic Acid Amplification Techniques ; methods ; RNA, Viral ; analysis ; Respiratory Syncytial Viruses ; genetics ; isolation & purification ; Respiratory System ; virology ; Respirovirus ; genetics ; isolation & purification ; Reverse Transcription ; Sensitivity and Specificity

OBJECTIVENucleic acid amplification (PCR) fluorogenic quantitative assay is used for the diagnosis of respiratory syncytial virus (RSV) infection. This study was designed to explore the sensitivity of PCR fluorogenic quantitative assay for ascertaining respiratory RSV infection and RSV infection conditions by detecting the presence of RSV-RNA related sequences in children.

METHODSBronchial and nasopharyngeal secretions specimens from 261 hospitalized children with respiratory tract infections from January 2007 to October 2008 were collected. Respiratory syncytial virus nucleic acid (RNA) in the specimens was measuredby PCR fluorogenic quantitative assay. Blood RSV-IgM was detected by enzyme linked immunosorbent assay (ELISA). The sensitivity for ascertaining respiratory RSV infection was compared between the two assays.

RESULTSThe RSV-RNA positive rate ascertained by PCR fluorogenic quantitative assay (38.7%) was significantly higher than blood RSV-IgM positive rate (21.1%) (p<0.01). The RSV-RNA positive rate (43.6%) in children at ages of less than 6 months was significantly higher than that in children at ages of 1 to three years (32.1%) (p<0.01). The RSV-RNA positive rate in children with bronchiolitis (58.5%) was the highest, followed by bronchopneumonia (38.2%) and acute bronchitis (20.0%).

CONCLUSIONSThe sensitivity of PCR fluorogenic quantitative assay for ascertaining respiratory RSV infection is higher. RSV is a major pathogen of lower respiratory tract infections in infants and young children. A higher rate of RSV infection is associated with a younger age. RSV infection is the most common in children with bronchiolitis.

Antibodies, Viral ; blood ; Child ; Child, Preschool ; Enzyme-Linked Immunosorbent Assay ; Female ; Fluorescence ; Humans ; Immunoglobulin M ; blood ; Infant ; Male ; Polymerase Chain Reaction ; methods ; RNA, Viral ; analysis ; Respiratory Syncytial Viruses ; genetics ; immunology ; isolation & purification ; Respiratory Tract Infections ; virology ; Sensitivity and Specificity ; Sputum ; virology

OBJECTIVES: An outbreak of acute febrile illness occurred in the Republic of Korea Air Force boot camp from May to July 2011. An epidemiological investigation of the causative agent, which was of a highly infective nature, was conducted. METHODS: Throat swabs were carried out and a multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) assay was performed to identify possible causative factors. RESULTS: The mean age of patients who had febrile illness during the study period was 20.24 years. The multiplex RT-PCR assay identified respiratory syncytial virus (RSV) as the causative agent. The main symptoms were sore throat (76.0%), sputum (72.8%), cough (72.1%), tonsillar hypertrophy (67.9%), and rhinorrhea (55.9%). The mean temperature was 38.75degreesC and the attack rate among the recruits was 15.7% (588 out of 3750 recruits), while the mean duration of fever was 2.3 days. The prognosis was generally favorable with supportive care but recurrent fever occurred in 10.1% of the patients within a month. CONCLUSIONS: This is the first epidemiological study of an RSV outbreak that developed in a healthy young adult group. In the event of an outbreak of an acute febrile illness of a highly infective nature in facilities used by a young adult group, RSV should be considered among the possible causative agents.
Adolescent ; Adult ; Antiviral Agents/therapeutic use ; Body Temperature ; Disease Outbreaks ; Humans ; Male ; Military Personnel ; Multiplex Polymerase Chain Reaction ; Oseltamivir/therapeutic use ; Pharynx/virology ; RNA, Viral/chemistry/genetics/metabolism ; Republic of Korea/epidemiology ; Respiratory Syncytial Virus Infections/drug therapy/*epidemiology/virology ; Respiratory Syncytial Viruses/*genetics/isolation & purification ; Sputum/virology ; Young Adult