R229I substitution from oseltamivir induction in HA1 region significantly increased the fitness of a H7N9 virus bearing NA 292K.

The proportion of human isolates with reduced neuraminidase inhibitors (NAIs) susceptibility in highly pathogenic avian influenza (HPAI) H7N9 virus was high. These drug-resistant strains showed good replication capacity without serious loss of fitness. In the presence of oseltamivir, R229I substitution were found in HA1 region of the HPAI H7N9 virus before NA R292K appeared.

The Epidemiological Pattern and Co-infection of Influenza A and B by Surveillance Network From 2009 to 2014 in Anhui Province, China.

Influenza-like illness (ILI) is one of the most important public health problems globally, causing an enormous disease burden. Influenza infections are the most common cause of ILI. Bacterial and virus co-infection is common yet the data of co-infection with influenza A and B viruses are scarce.

Interferon-induced Transmembrane Protein 3 Prevents Acute Influenza Pathogenesis in Mice.

Objective: Interferon-induced transmembrane protein 3 (IFITM3) is an important member of the IFITM family. However, the molecular mechanisms underlying its antiviral action have not been completely elucidated. Recent studies on IFITM3, particularly those focused on innate antiviral defense mechanisms, have shown that IFITM3 affects the body's adaptive immune response.

Features of Ebola Virus Disease at the Late Outbreak Stage in Sierra Leone: Clinical, Virological, Immunological, and Evolutionary Analyses.

We performed Ebola virus disease diagnosis and viral load estimation for Ebola cases in Sierra Leone during the late stage of the 2014-2015 outbreak (January-March 2015) and analyzed antibody and cytokine levels and the viral genome sequences. Ebola virus disease was confirmed in 86 of 1001 (9.7%) patients, with an overall case fatality rate of 46.

Detection of reassortant avian influenza A (H11N9) virus in environmental samples from live poultry markets in China.

Background: Avian influenza viruses have caused human infection and posed the pandemic potential. Live poultry markets are considered as a source of human infection with avian influenza viruses. Avian influenza routine surveillance of live poultry markets is taken annually in China.

H5N1 Avian Influenza Pre-pandemic Vaccine Strains in China.

Objective: To prepare the 4 candidate vaccine strains of H5N1 avian influenza virus isolated in China.

Methods: Recombinant viruses were rescued using reverse genetics. Neuraminidase (NA) and hemagglutinin (HA) segments of the A/Xinjiang/1/2006, A/Guangxi/1/2009, A/Hubei/1/2010, and A/Guangdong/1/2011 viruses were amplified by RT-PCR.

[Complete genome phylogenetic analysis of five H9N2 avian influenza viruses isolated from poultry flocks in Qinghai lake region].

Five H9N2 avian influenza virus strains were isolated from the environmental samples in live poultry market in Qinghai Lake region from July to September, 2012. To evaluate the phylogenetic characteristics of these H9N2 isolates, the eight gene segments were amplified by RT-PCR and sequenced. The phylogenetic and molecular characteristics of the five strains were analyzed.

A novel reassortant H2N3 influenza virus isolated from China.

Objective: To analyze the genetic composition of a novel H2N3 virus isolate identified from a duck cage swab in a live poultry market (LPM) in 2009 in Guangdong province of China.

Methods: PCR-positive specimens were inoculated into embryonated chicken eggs and subtyped by conventional RT-PCR. All segments of the virus A/environment/Guangdong/2/2009 were sequenced, and phylogenetic trees were constructed and analyzed.

[A review of H7 subtype avian influenza virus].

Since 2002, H7 subtype avian influenza viruses (AIVs) have caused more than 100 human infection cases in the Netherlands, Italy, Canada, the United States, and the United Kingdom, with clinical illness ranging from conjunctivitis to mild upper respiratory illness to pneumonia. On March 31st, three fatal cases caused by infection of a novel reassortant H7N9 subtype were reported in Shanghai City and Anhui Province in China. With the ability of H7 subtype to cause severe human disease and the increasing isolation of subtype H7 AIVs, we highlighted the need for continuous surveillance in both humans and animals and characterization of these viruses for the development of vaccines and anti-viral drugs.

A novel reassortant H3N8 influenza virus isolated from drinking water for duck in a domestic duck farm in Poyang Lake area.

Objective: To conduct a full genome sequence analysis for genetic characterization of an H3N8 influenza virus isolated from drinking water of a domestic duck farm in Poyang Lake area in 2011.

Methods: The virus was cultivated by specific pathogen free (SPF) chicken embryo eggs and was subtyped into hemagglutinin (HA) and neuraminidase (NA) by real-time PCR method. Eight gene segments were sequenced and phylogenetic analysis was conducted.

Development and validation of a commercial real-time NASBA assay for the rapid confirmation of influenza A H5N1 virus in clinical samples.

A real-time NASBA assay for the specific confirmation of influenza A H5N1 infection was developed and evaluated using proficiency panels distributed to the UK influenza network of laboratories and clinical samples received through the Chinese National Influenza Centre in Beijing. The aim of the proficiency panels was to determine the sensitivity and specificity of the assay on a range of influenza virus types and subtypes including different clades of influenza A H5 viruses. The assay was then evaluated using 19 clinical samples obtained from seven confirmed human cases of influenza A H5N1 infection in China.

[The virus isolation analysis of the H5N1 subtype human avain influenza cases in mainland China from 2005 to 2009].

Objective: To analyse the correlation between the virus isolation and the specimen collection of the H5N1 human high pathogenic avain influenza cases in Mainland China.

Methods: The specimens were collected in Mainland China from 2005.10 to 2009.

[Characterization of pseudotyped viruses coated with hemagglutinin of H5N1 avian influenza].

Objective: To construct pseudovirus bearing H5N1 HA based on a lentivirus vector system. Then we study the biological feature of the pseudovirus. With the newly established viral particles, we performed the serological tests.

[Colorimetric detection of human influenza A H1N1 virus by reverse transcription loop mediated isothermal amplification].

A simple, rapid and sensitive colorimetric Reverse Transcription Loop Mediated Isothermal Amplification (RT-LAMP) method was established to detect human influenza A H1N1 virus. The method employed a set of six specially designed primers that recognized eight distinct sequences of the HA gene for amplification of nucleic acid under isothermal conditions at 65 degrees C for one and half hour. The amplification process of RT-LAMP was monitored by the addition of HNB (Hydroxy naphthol blue) dye prior to amplification.

Visual detection of pandemic influenza A H1N1 Virus 2009 by reverse-transcription loop-mediated isothermal amplification with hydroxynaphthol blue dye.

A sensitive reverse-transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed for rapid visual detection of pandemic influenza A H1N1 virus infection. The reaction was performed in one step in a single tube at 65 degrees C for 60 min with the addition of hydroxynaphthol blue (HNB) dye prior to amplification. The detection limit of the RT-LAMP assay was approximately 60 copies, and no cross-detection was observed.

[Laboratory confirmation of the first influenza A (H1N1) imported case in Mainland China].

The clinical throat swab specimen of an imported suspected case of influenza A (H1N1) was detec ted with real-time PCR, RT-PCR and subsequently confirmed by gene sequencing. The presence of influ enza A (H1N1) virus confirmed the first case with A (H1N1) infection in Mainland China.

[Establishment of a method for rapid detection of the nucleic acid of the novel A (H1N1) influenza virus].

A new flu caused by a novel influenza A(H1N1) virus has spread over the United States, Mexico and more than 40 other countries. And because of the immediate global concern, WHO has announced that the current level of influenza pandemic alert is raised to phase 5, indicating approaching of an influenza pandemic. As patients suffering from the influenza A (H1N1) have the similar symptoms as patients with seasonal influenza, differential detection and identification of the influenza virus have to depend on specific laboratory tests.

[Detection of influenza viruses/avian influenza viruses and identification of virulence using a microarray].

Objective: To establish the DNA microarray to detect influenza viruses and avian influenza viruses, and identify their virulence.

Methods: Hemagglutinin (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).

[Laboratory diagnosis and molecular characterization analysis of the H5N1 influenza virus isolated from the first human case in Shenzhen, China].

The tracheal aspirates and serum samples of a suspected human case of high-pathogenic avian influenza (firstly found in Shenzhen, China) were collected and tested by a series of assays. The results showed that the RNA extracted from the tracheal aspirate specimens of the patient was confirmed positive for H5N1 avian influenza virus by Real-time PCR. The H5N1 avian influenza virus was isolated from patient's tracheal aspirates on MDCK cell and was named A/Guangdong/2/06(H5N1).

[Construction and transfection of eucaryotic expression recombinant vector containing truncated region of UL83 gene of human cytomegalovirus and it's sheltered effect as DNA vaccine].

To construct eucaryotic expression recombinant vector containing vivo truncated region of UL83 gene of human cytomegalovirus, realize its steady expression in Hep-2 cell, and study sheltered effect of the eucaryotic expression recombinant vector as DNA vaccine. A vivo truncated UL83 gene fragment encoding for truncated HCMV pp65 was obtained by PCR from human cytomegalovirus AD169 stock genome. By gene recombinant ways, the truncated UL83 gene fragment was cloned into eucaryotic expression vector pEGFP-C1 with reported gene coding GFP to construct recombinant vector pEGFP-C1-UL83.