Transmission risk of avian influenza virus along poultry supply chains in Guangdong, China.

Objectives: Avian influenza viruses (AIVs) poise significant risk to human health and the poultry industry. We evaluated the transmission risk along the poultry supply chain.

Methods: During October 2015 and July 2016, four rounds of cross-sectional surveys were performed to characterize AIV spread in farms, transport vehicles, slaughterhouses, wholesale and retail live poultry markets (LPMs).

[Evaluation on the risks of H5, H7 and H9 avian influenza infections in Guangzhou: using data from the 2006-2012 avian influenza surveillance program].

Objective: To analyze the results of avian influenza surveillance program in Guangzhou from 2006 to 2012 and to evaluate the risk of infections with H5, H7 and H9 subtypes avian influenza viruses.

Methods: Avian influenza surveillance system in Guangzhou consisted five components:serum surveillance on occupational population, environmental specimen surveillance of avian influenza virus, avian flu emergency surveillance, influenza viruses surveillance on ILI patient and surveillance on pneumonia of unknown causes. Hemagglutination inhibition test was conducted to detect the antibodies against H5, H7 and H9 while RT-PCR was used to test the nucleic acid of H5, H7 and H9 viruses.

[Risk evaluation on H7N9 avian influenza in Guangzhou, China].

Objective: We conducted both quick surveillance and evaluation programs within one week after the novel H7N9 influenza cases had been released by the Ministry of Health (MOH), to get the basic information on H7N9 virus in Guangzhou.

Methods: We sampled live birds from food markets and the natural habitat of birds to detect H7N9, H5 and H9 viruses. We interviewed workers from both markets and natural habitats.

[Investigation on the source of infection regarding an avian influenza (H5N1) case in Hong Kong that returning from Guangzhou].

Objective: We conducted an epidemiologic investigation to determine the source of infection on an avian influenza (H5N1) case who returned from Guangzhou, in Hong Kong.

Methods: Data related to epidemiologic investigation, medical observation on close contacts, Syndromic Surveillance on poultry salesmen, emergency monitoring, detection of the samples, source tracing on potential Avian influenza virus (H5, H7, H9) infected people, situation on environment pollution by avian influenza virus in the markets etc. were gathered.

[Study on immunogenicity of a recombinant adenovirus vaccine containing neuraminidase gene of H5N1 influenza virus (A/Anhui/1/2005) in mice].

Objective: To investigate immunity of a recombinant adenovirus vaccine (rAdV) containing codon-modified neuraminidase (Mod. NA) gene of H5N1 influenza virus in BALB/c mice and to screen for appropriate dose.

Methods: BALB/c mice were immunized with the rAdV-Mod.

[Study on the immunogenicity of adeno-vector vaccine against H5N1 influenza A virus].

Objective: To construct adenovirus vector vaccine against H5N1 influenza virus and study on the immunogenicity.

Methods: In this study, we amplified hemagglutinin (HA) gene sequence of H5N1 influenza virus (A/Anhui/1/2005), then constructed an adenovirus vector vaccine (Adv-HA), followed by tests in BALB/c mice for the immunogenicity with the vaccine and immunization strategies.

Results: The recombinate Adv-HA vaccine could effectively induce both humoral and cellular immunity against human H5N1 influenza virus.

[Epidemiological characteristic of first case of locally identified A/H1N1 secondary cases caused by imported source of infection in China].

Objective: To study the first locally identifed A/H1N1 secondary cases outbreak in China.

Methods: Interview and field investigation were integrated to describe the whole process of transmission on each case and to illustrate the relationships between the onset of the disease and the retated factors.

Results: Two contact persons appearanced fever and whose throat swabs were tested positive to H1N1 viral nucleic acid.

[Two recombinant adenovirus vaccine candidates containing neuraminidase Gene of H5N1 influenza virus (A/Anhui/1/2005) elicited effective cell-mediated immunity in mice].

The aim of this study is to develop the recombinant adenovirus vaccine (rAdV) candidates containing neuraminidase (NA) gene of H5N1 influenza virus and test in BALB/c mice the effect of cell-mediated immunity. In this study, two kind of NA gene (WtNA gene, the wild type; Mod. NA gene, the codon-modified type) derived from H5N1 influenza virus (A/Anhui/1/2005) were cloned and inserted respectively into plasmid of adenovirus vector, then the rAdV vaccines candidates (rAdV-WtNA and rAdV-Mod.

[Influence of avian influenza virus NS1 protein on the expression of IP-10 in BEAS-2B cells].

Objective: To investigate the influence of avian influenza virus (AIV) NS1 protein on the expression of interferon-inducible protein 10 (IP-10).

Methods: NSI gene from virus A/Anhui/1/2005 (H5N1), NS1 gene inserted with 80-84 amino acids from virus A/Anhui/1/2005 (H5N1) and NS1 gene from virus A/Puerto Rico/8/1934 (H1N1) were cloned into the eukaryotic expression vector pEGFP-N1, and transfected into BEAS-2B cells, IP-10 expression level in transfected cells was detected by flow cytometry.

Results: Compared with the control group pEGFP-N1, expression of these three different NS1 genes can down-regulate the expression of IP-10 in BEAS-2B cells, but there is no significant difference as to the lower level among them.

[Codon optimization of the H5N1 influenza virus HA gene gets high expression in mammalian cells].

In order to improve the expression of human avian influenza virus hemagglutinin (HA) and meet the pandemic influenza vaccine needs, we optimized and synthesized the whole length of HA gene of H5N1 (A/Anhui/1/2005) influenza virus in accordance with the human's codon preference, and inserted it to the eukaryotic expression vector pDC315 to construct a eukaryotic expression vector pDC315-Mod. HA. This plasmid and the eukaryotic expression vector pDC315-Wt.