[The fundamental role of stage control technology on the detectability for Salmonella networking laboratory].

Objective: To evaluated the fundamental role of stage control technology (SCT) on the detectability for Salmonella networking laboratories.

Methods: Appropriate Salmonella detection methods after key point control being evaluated, were establishment and optimized. Our training and evaluation networking laboratories participated in the World Health Organization-Global Salmonella Surveillance Project (WHO-GSS) and China-U.

[Molecular analysis on non-O1 and non-O139 Vibrio cholerae isolates].

Objective: According to results from the two-month consecutive surveillance program in Maanshan, six suspected cases of non-O1 non-O139 Vibrio (V.) cholerae infection, were found that called for identification of pathogens as well as molecular-epidemiological analysis to determine the aggregation of the epidemic situation.

Methods: Biochemical and serotype identification, hemolysis test, and drug sensitive test were used to detect the drug resistance spectrum.

[Design and implementation of Geographical Information System on prevention and control of cholera].

To build the Geographical Information System (GIS) database for prevention and control of cholera programs as well as using management analysis and function demonstration to show the spatial attribute of cholera. Data from case reporting system regarding diarrhoea, vibrio cholerae, serotypes of vibrio cholerae at the surveillance spots and seafoods, as well as surveillance data on ambient environment and climate were collected. All the data were imported to system database to show the incidence of vibrio cholerae in different provinces, regions and counties to support the spatial analysis through the spatial analysis of GIS.

Association between the incidence of typhoid and paratyphoid fever and meteorological variables in Guizhou, China.

Background: Typhoid/paratyphoid fever (TPF) is endemic in Guizhou. We conducted wavelet analysis and Spearman's rank correlation analysis to explore the impact of meteorological variations on TPF infection in Guizhou, in an attempt to assess the risk factors associated with TPF epidemics.

Methods: We examined the association between TPF incidence in Guizhou and temperature, precipitation and relative humidity using 24 years of data from 1984 to 2007.

[Surveillance program on and the distribution related to the virulence-associated genes of Vibrio cholerae in estuary of Pearl River].

Objective: To understand the distribution, molecular characteristics and virulence genes of the O1 and O139 Vibrio cholerae isolates from the Pearl River Estuary water.

Methods: Vibrio cholerae isolates collected from the Pearl River estuary waters from January 2009 to December 2010, were tested by PCR for eight virulence-related genes, including cholera toxin (ctxA), zonula occludens toxin (zot), accessory cholera enterotoxin (ace), hemolysin (hlyA), toxin-coregulated pilus (tcpA), outer membrane protein (ompU), and the regulatory protein genes (tcpI, toxR). Genetic relation was assessed by pulsed-field gel electrophoresis (PFGE) and the patterns were clustered by BioNumerics.

[Typhoid and paratyphoid fever in Yunnan province: distributional patterns and the related meteorological factors].

Objective: To characterize the spatial distribution of typhoid and paratyphoid fever (TPF) in Yunnan province, China and to determine the effectiveness of meteorological factors on the epidemics of TPF.

Methods: Data of reported TPF cases in Yunnan province (2001 - 2007) from the China Information System for Diseases Control and Prevention was applied to GIS-based spatial analyses to detect their spatial distribution and clustering of TPF incidence at the county level. Panel data analysis was used to identify the relationships between the TPF incidence and meteorological factors including monthly average temperature, monthly cumulative precipitation and monthly average relative humidity.

[Molecular subtyping of Vibrio cholerae isolates from outbreaks of cholera by pulsed-field gel electrophoresis in Hainan in 2008].

Objective: To analyze the molecular characteristics and genetic correlations of Vibrio cholerae isolates in Hainan in 2008, so as to provide pathogenic proof to diagnose the plague.

Methods: Seventy six cholera strains were isolated from this cholera epidemic.69 strains were obtained from patients, 7 were isolated from external environment, among which, one was from patient's toilet, one from water sample, three were isolated from fish pond near patient's home, one came from swab of the patient vomit on the ground of health center and one from swab of kitchen knife from Hainan University canteen respectively.

Phenotypic and genotypic characterization Vibrio cholerae O139 of clinical and aquatic isolates in China.

To enhance the understanding of epidemiological impact of environmental Vibrio cholerae O139 strains, we characterized 10 clinical and 20 environmental isolates collected from human clinical samples and Pear River estuary during 2006 to 2008. Isolates were tested by PCR for eight virulence genes: cholera toxin (ctxA), zonula occludens toxin (zot), accessory cholera enterotoxin (ace), hemolysin (hlyA), NAG-specific heat-stable toxin (st), toxin-coregulated pilus (tcpA), outer membrane protein (ompU), and regulatory protein genes (tcpI). Genetic relatedness was assessed by pulsed-field gel electrophoresis (PFGE), and antibiotic susceptibility was determined using disk diffusion.

[Isolation and characterization of Shewanella spp. from patients of food poisoning].

Objective: To identify the isolates of Shewanella spp. from specimens of food poisoning based on biological and biochemical analysis.

Methods: Strains were obtained from the investigation on two food poisoning episodes in September and October, 2007 in Ma'anshan city, Anhui province.

[A duplex nested PCR assay detecting of Vibrio cholerae and its application on environmental specimens].

Objective: To establish a duplex nested PCR assay system which is capable for detecting O1 and O139 groups of Vibrio cholerae simultaneously, and is applicable to environmental specimens from routine cholera surveillance.

Methods: Based on nucleic acid sequences available in GenBank, six sets of primers were designed by PrimerSelect program of DNAStar, targeting the rfb gene that encodes the O antigens of O1 and O139 V. cholerae, respectively.

[Development of TaqMan real-time PCR in detection of Aeromonas hydrophila].

Objective: To develop a TaqMan real-time PCR for the detection of Aeromonas hydrophila.

Methods: The conserved region of major adhesion gene of Aeromonas hydrophila (aha) was used to design primers and TaqMan probe. A total of six concentration gradients for forward and reverse primers ranging from 200 -700 nmol/L were chosen, and four concentration gradients for probe ranging from 100 - 400 nmol/L were chosen.

[Isolation, identification and 16S rDNA phylogenetic analysis of Klebsiella pneumonia from diarrhea specimens].

Objective: To understand the biochemical characteristics and 16S rDNA genetic sequence evolution of strains isolated from diarrhea specimens so as to provide basis for classification and identification of Klebsiella pneumoniae.

Methods: Specimens were cultured using MacConkey and SS medium. All isolates were identified as K.

[The etiologic characteristics of Vibrio cholerae in Guangdong province in 2007].

Objective: To analyze the etiologic characteristics of Vibrio cholerae in Guangdong province in 2007. Genetic relationship was observed including among predominated biotype isolates from different areas within the province and among same biotypes isolates from cholera cases and regular surveillance.

Methods: Isolates from cholera cases and through environmental surveillance were typed by sero- and phage- typings.

[Distribution and molecular characteristics of Vibrio cholerae serogroups O1 and O139 isolates in estuary of Pearl River].

Objective: Through systematic monitoring of the number and strain types of O1 and O139 Vibrio cholerae in the Pearl River estuary waters to analyze it's relevance with the temperature of environment, and the relevance between strains in water and isolates during outbreaks and epidemics as well as to estimate the methods used for environmental water detection and the potential role in cholera surveillance program.

Methods: Twenty-four stations along the Pearl River were selected and the water samples were collected monthly from March 2006 to February 2007. V.

[Development and application of real-time polymerase chain reaction to detect Vibrio cholerae O1 and O139 in river water].

Objective: To develop a real-time SYBR Green polymerase chain reaction (PCR) for detection of Vibrio cholerae serogroups O1 and O139, and to evaluate its reliability through detection of estuary water samples.

Methods: O antigen rfb genes specific for O1 and O139 were used for the design of PCR primers. The real-time SYBR Green PCR system in detecting O1 and O139 specific rfb genes in one tube was developed, and its sensitivity, specificity and reproducibility were evaluated.

[Identification and molecular study on vibrio cholerae in sea products].

Objective: To investigate the serologic type, phage-biotype and toxic factor of Vibrio cholerae isolated from different sea products, analyze the relation between the Vibrio cholerae in sea products and cholera epidemiology, and provide references for forecasting cholera epidemic situation and drawing out a preventing plan.

Method: The biotype of strains isolated was analyzed by using type and phage-biotype serological methods. The toxic gene was detected by PCR.

[Investigation on status of pollution of vibrio cholera in seafood and aquatic products in 12 provinces of China in 2005].

Objective: To understand the pollution rates of vibrio cholera (V. cholera) in different seafood, aquatic products and their circulatory processes, so as to help making measures for cholera control and prevention.

Methods: Different seafood, aquatic products and breed water specimen collected from 12 provinces of China were tested from July to September in 2005.

[Sequencing and analysis of Vibrio cholerae typing phage VP3 genome].

DNA sequence and the genome of phage VP3 (a typing phage of V. cholera) were analyzed. A random library of VP3 DNA was constructed by shot-gun library method.

[Functional analysis of promoters of Vibrio cholerea typing phage VP1 with reporter system].

Phage VP1 infects and lyses Vibrio cholerae. The VP1 genome is a circular double-strand DNA and its size is 32176 base pairs. Analysis of the sequence of the VP1 genome revealed the presence of 15 putative promoter sequence.