Animals ; Humans ; Influenza, Human ; virology ; Orthomyxoviridae ; genetics ; isolation & purification ; Orthomyxoviridae Infections ; epidemiology ; veterinary ; virology ; Swine ; Swine Diseases ; virology ; Viral Proteins ; genetics

A novel H17N10 subtype of the influenza A viruses was found in bats in 2012. Protein sequence and structural analyses revealed that the HA17 and NA10 proteins of this strain are different from corresponding ones in known influenza A subtype viruses. Both HA17 and NA10 proteins cannot bind to sialic acid,which indicates that they may have novel functions. This article briefly describes the state of current research into the H17N10 subtype of bat influenza A virus.
Animals ; Chiroptera ; virology ; Influenza A virus ; classification ; genetics ; isolation & purification ; metabolism ; Orthomyxoviridae Infections ; veterinary ; virology ; Viral Proteins ; genetics ; metabolism

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

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

Animals ; Humans ; Influenza A Virus, H1N1 Subtype ; genetics ; isolation & purification ; Influenza, Human ; virology ; Orthomyxoviridae Infections ; veterinary ; virology ; Recombination, Genetic ; Swine ; Swine Diseases ; virology ; Terminology as Topic ; Viral Proteins ; genetics

OBJECTIVETo establish the DNA microarray to detect influenza viruses and avian influenza viruses, and identify their virulence.

METHODSHemagglutinin (HA), neuramidinase (NA) and nucleoprotein(NP) genes were chosen simultaneously as targets for designing a microarray used for detection of viruses and identification virulence. The nucleic acid were amplified by single primer amplication (SPA). And then its specificity,sensitivity and reproducibility were evaluated.

RESULTSThe microarray was able to specially detect H1N1, H3N2, B influenza viruses and H5N1, H9N2 avian influenza viruses. Their limits were 8HAU, 16HAU, 32HAU, and 8HAU, 8HAU respectively. The limit for virulence was 32HAU. When samples were analyzed by both RT-PCR and microarray in parallel, the results agreed in 83.9% (47/56).

CONCLUSIONThe microarray can detect and distinguish five tested viruses, and especially identify virulence. It not only supplies an assistant tool for clinical diagnosis and control of infectious disease, but also is valuable for controlling and preventing outbreak of avian influenza epidemic.

Animals ; Birds ; Humans ; Influenza A virus ; genetics ; isolation & purification ; pathogenicity ; Influenza in Birds ; virology ; Influenza, Human ; virology ; Microbiological Techniques ; Oligonucleotide Array Sequence Analysis ; methods ; Orthomyxoviridae ; genetics ; isolation & purification ; pathogenicity ; RNA, Viral ; analysis ; Reverse Transcriptase Polymerase Chain Reaction ; Sensitivity and Specificity ; Virulence ; genetics

In 2006, a swine influenza virus (SIV) isolate was isolated from 30 nasal swabs samples collected from pigs with clinical syndromes of swine influenza in a pig farm of Liaoning Province. The virus isolate was studied and identified by the growth in 9-11 days old chicken embryo, hemagglutination (HA) assay, hemagglutination inhibition (HI) assay, reverse transcription-polymerase chain reaction assays (RT-PCR) for its genetic subtype, whole gene sequence analysis and animal trial for its virulence. The virus isolate demonstrated the hemagglutination activity. Result of HI test against H1 subtype of SIV was positive, however, the results were negative when the HI studies were conducted using SIV H3 subtype virus and Newcastle Disease Virus (NDV). Eight gene segments of the virus isolate were amplified by RT-PCR. Phylogenetic analysis of the gene sequence of the virus isolate by using DNAstar software program revealed that the isolate have the H1 HA gene, by comparing to the sequences of H1-H16 in the GenBank. Furthermore, sequencing results also demonstrated that the virus isolate's NA gene belongs to N1 subtype. Therefore, the subtype of the SIV isolate is H1N1. The results of sequence analysis indicated that the genome of the SIV-H1N1 LN strain includes 8 fragments, among which only M protein gene is not swine originated. All other 7 fragments have close relationship with the domestic standard swine H1N1 strains. Results suggested that the SIV isolate LN strain might be created by a possible triple reassortants among the classic swine influenza virus, human influenza-like virus, and avian influenza-like virus. Piglets were inoculated with the SIV LN strain virus preparations and the virus caused the typical clinical symptoms of swine influenza in the inoculated piglets. This study, the isolation, identification and genetic analysis of the SIV LN strain provided useful information and basic data for the further investigation of epidemic principles and patterns of swine influenza virus in China.
Animals ; Hemagglutination Inhibition Tests ; Influenza A Virus, H1N1 Subtype ; classification ; genetics ; isolation & purification ; Lung ; virology ; Orthomyxoviridae Infections ; virology ; Phylogeny ; Swine ; Swine Diseases ; virology

Swine influenza viruses (SIVs) are respiratory pathogens of pigs. They cause both economic bur den in livestock-dependent industries and serious global public health concerns in humans. Because of their dual susceptibility to human and avian influenza viruses, pigs are recognized as intermediate hosts for genetic reassortment and interspecies transmission. Subtypes H1N1, H1N2, and H3N2 circulate in swine populations around the world, with varied origin and genetic characteristics among different continents and regions. In this review, the role of pigs in evolution of influenza A viruses, the genetic evolution of SIVs and interspecies transmission of SIVs are described. Considering the possibility that pigs might produce novel influenza viruses causing more outbreaks and pandemics, routine epidemiological surveillance of influenza viruses in pig populations is highly recommended.
Animals ; Humans ; Influenza A virus ; genetics ; isolation & purification ; physiology ; Influenza, Human ; epidemiology ; transmission ; virology ; Orthomyxoviridae Infections ; epidemiology ; transmission ; veterinary ; virology ; Swine ; Swine Diseases ; epidemiology ; transmission ; virology

Animals ; Global Health ; History, 20th Century ; Humans ; Influenza A virus ; genetics ; isolation & purification ; Influenza, Human ; epidemiology ; history ; mortality ; virology ; Orthomyxoviridae Infections ; epidemiology ; veterinary ; virology ; Swine ; Swine Diseases ; epidemiology ; virology

OBJECTIVETo understand the epidemics and antigenic drift of influenza viruses in China from 2000 to 2001.

METHODSThe viruses were grown in embryonated hen eggs with 9 - 10 days old. The egg allantoic fluids with influenza viruses were used. Virion RNA was transcribed into cDNA by reverse transcriptase while cDNA amplified by PCR. Products of PCR were purified. RNA sequence analysis was then performed. Finally, phylogenetic analysis of the sequencing data was performed with MegAlign (Version 1.03) and Editseq (Version 3.69) software.

RESULTSData from comparison of amino acid sequence on HA1 domain of HA protein molecule between H1N1 viruses isolated in 2001 and A/Shanghai/7/99 (H1N1) strain indicated that there was only one difference of amino acid located at 190 position (antigenic determinant D). However, phylogenetic analysis showed that there were two distinguishable genetically lineages of H1N1 viruses co-circulating in men in China in 2001. Two antigenically distinct genetic lineages of influenza B viruses were still existing in men in China. Most of influenza B viruses were Yamagata-like strain and there were two different amino acid sequences located at 197 and 199 position on HA1 domain of HA protein molecule, between Victoria-like virus isolated and B/Shandong/7/97 strain. When comparing amino acid sequences on HA1 protein domain of H3N2 viruses isolated in 2000 with those of A/Sydeney/5/97 (H3N2) virus, it was revealed that there were 7 - 8 differences of amino acid sequences between them. However, there were four differences related to amino acid sequences on HA1 protein domain between H3N2 viruses isolated in 2000 and in 2001. These results were further demonstrated by analysis of phylogenic tree.

CONCLUSIONSInfluenza was not prevalent in China from 2000 to 2001. The antigenic drifts of H3N2 and B/Victoria-like viruses occurred. Two antigenically distinct genetic lineages of influenza B viruses were still co-circulating in men in China. Two genetically distinct lineages of influenza A (H1N1) virus were also co-circulating in men in China.

Antigens, Viral ; genetics ; China ; epidemiology ; DNA, Viral ; genetics ; Female ; Genes, Viral ; genetics ; Genetic Variation ; Hemagglutinin Glycoproteins, Influenza Virus ; genetics ; Humans ; Influenza A virus ; classification ; genetics ; immunology ; isolation & purification ; Influenza B virus ; classification ; genetics ; immunology ; isolation & purification ; Influenza, Human ; epidemiology ; virology ; Male ; Orthomyxoviridae ; classification ; genetics ; Phylogeny ; Reverse Transcriptase Polymerase Chain Reaction ; Sentinel Surveillance ; Sequence Analysis, RNA