Distribution of avian influenza viruses according to environmental surveillance during 2014-2018, China.

Background: Recurrent infections of animal hosts with avian influenza viruses (AIVs) have posted a persistent threat. It is very important to understand the avian influenza virus distribution and characteristics in environment associated with poultry and wild bird. The aim of this study was to analyze the geographic and seasonal distributions of AIVs in the 31 provinces, municipalities and autonomous region (PMA) of China, compare the AIVs prevalence in different collecting sites and sampling types, analyze the diversity of AIVs subtypes in environment.

Viral mimic polyinosine-polycytidylic acid potentiates liver injury in trichloroethylene-sensitized mice - Viral-chemical interaction as a novel mechanism.

Occupational trichloroethylene (TCE) exposure can induce hypersensitivity dermatitis and severe liver injury. Recently, several clinical investigations indicate that viral infection, such as human herpesvirus-6, is associated with hepatic dysfunction in patients with TCE-related generalized skin disorders. However, whether viral infection potentiates TCE-induced liver injury remains unknown.

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.

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.

[Molecular characterization of highly pathogenic avian influenza A (H5N1) viruses isolated from humans in Hunan province, 2006 - 2009].

Objective: To understand the possible origins, genetic re-assortment and molecular characterization of 4 highly pathogenic avian influenza A (H5N1) viruses isolated from humans in Hunan province, between 2006 and 2009.

Methods: H5N1 PCR test-positive specimens were inoculated in embryonated eggs while H5N1 virus was isolated and genomes sequenced. Genome homology and genetic molecular characterization were analyzed by BLAST and MEGA 4.

[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.

[Construction and characterization of reverse genetic system for H9N2 avian influenza].

Objective: To provide a technology platform for vaccine development as well as the research on transmission and pathogenesis, the reverse genetic system for H9N2 avian influenza virus was established.

Methods: Eight full-length cDNAs of avian influenza virus A/Guangzhou/333/99 (H9N2) were amplified by RT-PCR and separately cloned into the transcription/expression vector, pCI-polI. The 8 plasmids DNA was cotransfected into 293T cell, the cell supernatant was collected and inoculated into embryonated eggs, the rescued virus from the allantoic fluid was identified by hemagglutinination assay.

[Characteristic analysis of NA gene of human influenza viruses (H3N2) isolated from 1996 to 2005 in China].

The NA genes of 395 strains of human H3N2 influenza virus isolated from 1996 to 2005 in China were sequenced, analyzed with bioinformatics tools. The NA nucleotide sequence of phylogenetic tree showed a main evolution branch with multiple short side branches. The strains in the same year may be divided into several branches.

[Study on the correlation of human influenza A/H3N2 hemagglutinin gene variation and the epidemic from 1995 to 2005 in China].

To study the correlation of human influenza A/H3N2 hemagglutinin gene variation and the epidemic from 1995 to 2005 in China, 550 HA1 sequences of H3N2 viruses isolated in China were analyzed with phylogenetic tree. The results showed that the evolution of HA1 represented a long trunk with short side branches. The animo acid changes of HA1 mostly located at the antigenic sites or aside of them, but also may occur at the other sites simultaneously.

[Adamantane resistance among influenza A (H3N2) viruses isolated from the mainland of China].

Background: To study the incidence of adamantane resistance among influenza A (H3N2) viruses isolated from the mainland of China since 1989 through our influenza surveillance system, and to provide more information for the clinical usage of adamantane drugs.

Methods: Totally 584 influenza A (H3N2) virus strains were randomly selected from our surveillance network since 1989, the adamantane drug resistance related gene M2 of all 584 strains was sequenced, and the drug sensitivity of viruses was also assayed by using biological methods in cells.

Results: No adamantane resistant strains were detected among the strains isolated from 1989 to 1999, but there was a surprisingly increased resistance rate of 56% in 2003 compared with 3.