OBJECTIVETo analysis the etiological and epidemiological characteristics of the reported infectious diarrhea (other than cholera, dysentery, typhoid and paratyphoid) cases in China in 2011.

METHODSA total of 836 591 reported infectious diarrhea cases were collected from "China Information System for Disease Prevention and Control" since first week to fifty-second weeks in 2011, 59 929 out of which were laboratory-confirmed. The information of thirty public health emergencies relevant with infectious diarrhea was collected from "Emergency Public Reporting System" between first week and fifty-second weeks in 2011. The epidemiological characteristics of reported cases, confirmed cases and outbreaks, and the pathogenic spectrum of confirmed cases were then analyzed.

RESULTSIn 2011, 836 591 infectious diarrhea cases (other than cholera, dysentery, typhoid and paratyphoid) were reported, and the incidence rate was 62.39/100 000. More than half patients were children aged under 5 year-old, accounting for 52.13% (436 098/836 591) and the incidence rate was 447.06/100 000 (436 098 cases). Most of the ill children were scattered, accounting for 50.53% (422 752/836 591). Reported cases showed two incidence peaks, with a summer peak from twenty-third weeks to thirty-fifth weeks, accounting for 34.33% (287 231/836 591) and a winter peak from forty-third weeks to fifty-second weeks, accounting for 23.54% (196 939/836 591). Cases distributed all over China, the incidence in Beijing (253.00/100 000 (49 619 cases)), Tianjin (244.34/100 000 (31 614 cases)), Zhejiang (204.42/100 000 (111 257 cases)), Ningxia (132.16/100 000 (9328 cases)) and Guangdong (127.40/100 000 (132 880 cases)) ranked the top five. Among the 30 public health emergencies, 5 outbreaks had lab tested pathogenic results, including 4 were norovirus-induced. Laboratory-confirmed cases accounted for 7.16% (59 929/836 591) of the case reported, including 56 687 viral cases and 3242 bacterial cases. Rotavirus cases took the highest proportion of viral cases, at 97.35% (53 612/55 185); and 97.15% (53 612/55 185) of which were children aged under 5 year-old. 82.42% (45 480/55 185) of the cases distributed in Guangdong and Zhejiang province, with the incidence peak from fiftieth weeks to fifty-first weeks, accounting for 15.42% (8508/55 185) of the whole year cases. The main pathogens of bacterial diarrhea were Salmonella, Vibrio parahaemolyticus and Escherichia coli, accounting for 48.43% (1570/3242), 32.20% (1044/3242) and 8.57% (278/3242) respectively, with the incidence peak from thirty-first weeks to thirty-fifth weeks, accounting for 23.01% (746/3242). Salmonella infection patients were mainly from Shanghai, Guangdong and Zhejiang province (91.59% (1438/1570)), Vibrio parahaemolyticus patients were mainly from Shanghai (80.94% (845/1044)), and Escherichia coli patients were mainly from Guangdong province (84.17% (234/278)). Salmonella patients were concentrated in 0-9 years group, accounting for 42.36% (665/1570), while Vibrio parahaemolyticus patients in 20-39 years group, accounting for 81.99% (856/1044), and Escherichia coli patients in under 1 year old and 20-39 years group, accounting for 63.67% (177/278).

CONCLUSIONIn China, children aged under 5 year-old should be the priority population in surveillance of infectious diarrhea. Rotavirus is the main pathogen causing infectious diarrhea. The lab-testing and case-reporting capabilities differed greatly among areas.

Child, Preschool ; China ; epidemiology ; Cholera ; epidemiology ; Diarrhea ; epidemiology ; microbiology ; virology ; Dysentery ; epidemiology ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Rotavirus Infections ; epidemiology ; Typhoid Fever ; epidemiology

When cholera was first detected in Papua New Guinea (PNG) in mid-2009, national diagnostic capacity faced many challenges. This was in part due to the non-endemic status of the outbreak, resulting in few local staff experienced in Vibrio cholerae detection and poor access to the required consumables. The PNG Institute of Medical Research conducted culture on specimens from suspected cholera patients in Madang Province, with presumptive V. cholerae isolates sent to Goroka for confirmation. Of 98 samples analysed 15 were culture positive, with V. cholerae detected by polymerase chain reaction (PCR) in an additional 3 samples. Further analyses were conducted to identify other pathogenic bacteria from thiosulphate citrate bile salt sucrose (TCBS) agar. Molecular-based assays detected enteropathogenic (n = 1) and enterotoxigenic (n = 1) strains of Escherichia coli. No other major enteric pathogens were detected. The low detection rate of V. cholerae at the provincial level reflects challenges in the laboratory diagnosis of cholera and in-country challenges in responding to an outbreak of a non-endemic disease, such as lack of in-country diagnostic expertise and available consumables in the early stages. It also suggests that full aetiological investigations are warranted in future outbreaks of acute watery diarrhoea in PNG to fully elucidate the potentially complex aetiology, which could in turn guide diagnostic, treatment and prevention measures.
Cholera/*epidemiology/*microbiology ; *Disease Outbreaks ; Enterobacteriaceae/isolation & purification ; Feces/microbiology ; Humans ; Immunoassay ; Papua New Guinea/epidemiology ; Polymerase Chain Reaction ; Vibrio cholerae/*isolation & purification

Corn, one of the most important forage crops worldwide, has proven to be a useful expression vehicle due to the availability of established transformation procedures for this well-studied plant. The exotoxin Apx, a major virulence factor, is recognized as a common antigen of Actinobacillus (A.) pleuropneumoniae, the causative agent of porcine pleuropneumonia. In this study, a cholera toxin B (CTB)-ApxIIA#5 fusion protein and full-size ApxIIA expressed in corn seed, as a subunit vaccine candidate, were observed to induce Apx-specific immune responses in mice. These results suggest that transgenic corn-derived ApxIIA and CTB-ApxIIA#5 proteins are potential vaccine candidates against A. pleuropneumoniae infection.
Actinobacillus Infections/microbiology/*prevention & control ; Actinobacillus pleuropneumoniae ; Animals ; Antigens, Bacterial/immunology ; Bacterial Proteins/*immunology ; Bacterial Vaccines/*immunology ; Cholera Toxin/*chemistry ; Female ; Hemolysin Proteins/*immunology ; Immunization, Secondary ; Mice ; Mice, Inbred ICR ; Plants, Genetically Modified ; Zea mays/*genetics

OBJECTIVETo understand the genetic structures and variations of the superintegron (SI) in Vibrio cholerae isolated in the seventh cholera pandemic.

METHODSPolymerase chain reaction scanning and fragment sequencing were used. Sixty toxigenic V. cholerae O1 El Tor strains isolated between 1961 and 2008 were analyzed.

RESULTSSome variations were found, including insertions, replacements, and deletions. Most of the deletions were probably the result of recombination between V. cholerae repeat sequences. The majority of the variations clustered together. The SIs of the strains isolated in the 1960s and 1970s showed more diversity, whereas SI cassette variations in strains isolated in the 1990s and after were lower, with ∼24 kb signature sequence deletion. This indicates the predominant SI in the host during the epidemic in the 1990s and after. The insertion cassettes suggested the mobilization from the SIs of other V. cholerae serogroups and Vibrio mimicus.

CONCLUSIONThe study revealed that structural variations of SIs were obvious in the strains isolated in epidemics in different decades, whereas the divergence was based on syntenic structure of SIs in these El Tor strains. Also, the continuing cassette flows in the SIs of the host strains during the seventh cholera pandemics were displayed.

Cholera ; epidemiology ; microbiology ; Chromosomes, Bacterial ; genetics ; ultrastructure ; Cluster Analysis ; DNA, Bacterial ; genetics ; Electrophoresis, Gel, Pulsed-Field ; Gene Deletion ; Gene Flow ; Genetic Variation ; Humans ; Integrons ; genetics ; Mutagenesis, Insertional ; Open Reading Frames ; genetics ; Polymerase Chain Reaction ; Tandem Repeat Sequences ; Vibrio cholerae O1 ; classification ; genetics ; isolation & purification ; ultrastructure

Vibrio cholerae is an important foodborne pathogen, mainly causes acute intestinal infectious disease. The development of rapid method for detecting Vibrio cholerae is critical for early diagnosis of its infection. In this study, two pairs of specific primers were designed according to housekeeping gene mdh of Vibrio cholerae. Following optimization of the reaction, DNA loop-mediated isothermal amplification (LAMP) for rapidly detecting Vibrio cholerae was successfully established. The optimal reaction for the LAMP assay is 65 degrees C for 60 min, with detection limit for cultivated Vibrio cholerae of 25 CFU/mL and for its contaminated food of 32 CFU/g. The specificity of the assay was determined using thirty-three kinds of same species or closely related bacteria, only Vibrio cholerae strains were specifically amplified. In practice, 85 pieces of positive samples were detected from 1057 pieces of shrimps, crabs, oysters, meat and human diarrhea complex using the LAMP method, which accorded with the detection result by ISO TS 21872-1-2007. Thus, the LAMP assay established in this study is a sensitive, rapid and simple tool for detecting Vibrio cholerae and will facilitate the surveillance for its control.
Cholera ; microbiology ; Food Microbiology ; methods ; Meat ; microbiology ; Nucleic Acid Amplification Techniques ; methods ; Seafood ; microbiology ; Sensitivity and Specificity ; Vibrio cholerae ; genetics ; isolation & purification

OBJECTIVETo understand the epidemic condition, distribution and biological characteristics of non-O1/non-O139 Vibrio cholerae from 2001 to 2009 in Haizhu District, to provide a scientific basis for the prevention and control of acute diarrhea.

METHODSReferring to the detecting method written in "Cholera control handbook" in the fifth edition, 764 specimens from outside environment (including the water in the Pearl River, drinking water, water for breeding fish, aquatic products and delicatessen foods), 189 specimens of healthy population and 3398 intestinal samples of patients with diarrhea, summing up to 4351 specimens for non-O1/non-O139 Vibrio cholerae test.

RESULTS4,351 specimens were detected of 101 strains of non O1/non O139 Vibrio cholerae, the total detection rate was 2.32%; 66 strains were identified by serotyping and grouped into 26 different serotypes, the typing rate was 65.3%. The strains VBO9, VBO38 and VBO76 were the dominant bacteria.Nine strains of the same type of non-O1/non-O139 Vibrio cholerae were found from external environments also from patients with diarrhea, suggesting that there might be a correlation between the two.

CONCLUSIONNon-O1/non-O139 Vibrio cholerae have diversified serotypes, causing certain infection rate among the population in this region. These bacteria exist extensively in external environment and they are the potential hazard to the citizens.

China ; epidemiology ; Cholera ; epidemiology ; microbiology ; Humans ; Serotyping ; Vibrio cholerae ; classification ; isolation & purification

OBJECTIVETo 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.

METHODSSeventy 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. With conventional aetiological methods, pulse-field gel electrophoresis was conducted and the patterns of the 76 isolates were analyzed. The PFGE image was analyzed using BioNumerics (Version4.0, Applied Maths BVBA, Belium). Image bands were identified and similarity coefficient was automatically generated.

RESULTSSeventy six strains were isolated from Vibrio cholerae outbreaks in Hainan in 2008.5 PFGE patterns of patient's isolates in June were the same, sharing a similarity coefficient of 100%. 70 PFGE patterns of patients and water in October and November were completely same, the similarity coefficient being 100%. But they were not same as that of June. 1 PFGE pattern of isolate from the sample in Hainan University was different, only sharing a similarity coefficient of 79.7%, which showed no correlation with the outbreak.

CONCLUSIONDifferent outbreaks of Vibrio cholera occurred in Hainan in 2008. The epidemic in October and November at different counties was one outbreak. The pollution of water in environment was an important factor for outbreak.

Bacterial Typing Techniques ; methods ; China ; epidemiology ; Cholera ; epidemiology ; microbiology ; DNA, Bacterial ; Disease Outbreaks ; Electrophoresis, Gel, Pulsed-Field ; methods ; Humans ; Vibrio cholerae ; classification ; isolation & purification

INTRODUCTIONWe carried out an epidemiological review of cholera in Singapore to determine its trends and the factors contributing to its occurrence.

MATERIALS AND METHODSEpidemiological data of all notified cases of cholera maintained by the Communicable Diseases Division, Ministry of Health, for the period 1992 to 2007 were collated and analysed. Case-control studies were carried out in outbreaks to determine the source of infection and mode of transmission. Linear patterns in age and ethnic distribution of cholera cases were assessed using chi2 test for trend.

RESULTSThere were a total of 210 cholera cases reported between 1992 and 2007. The incidence of cholera declined from 17 cases in 1992 to 7 cases in 2007. About a quarter of the cases were imported from endemic countries in the region. Between 76% and 95% of the reported cases were local residents. Four elderly patients with comorbidities and who sought medical treatment late died, giving a case-fatality rate of 1.9%. Vibrio cholerae 01, biotype El Tor, serotype Ogawa, accounted for 83.8% of the cases. The vehicles of transmission identified in outbreaks included raw fi sh, undercooked seafood and iced drinks cross-contaminated with raw seafood.

CONCLUSIONWith the high standard of environmental hygiene and sanitation, a comprehensive epidemiological surveillance system and licensing and control of food establishments, cholera could not gain a foothold in Singapore despite it being situated in an endemic region. However, health education of the public on the importance of personal and food hygiene is of paramount importance in preventing foodborne outbreaks. Physicians should also maintain a high level of suspicion of cholera in patients presenting with severe gastroenteritis, especially those with a recent travel history to endemic countries.

Adolescent ; Child ; Child, Preschool ; Cholera ; microbiology ; mortality ; Disease Outbreaks ; statistics & numerical data ; Female ; Foodborne Diseases ; epidemiology ; prevention & control ; Humans ; Incidence ; Infant ; Infant, Newborn ; Male ; Middle Aged ; Population Surveillance ; Singapore ; epidemiology ; Vibrio cholerae O1 ; isolation & purification ; Young Adult

OBJECTIVETo establish a loop-mediated isothermal amplification (LAMP) method for rapid diagnosis of Vibrio cholerae.

METHODSBased on the ompW nucleic sequence of Vibrio cholerae, a pair of primers was designed for LAMP. The reaction conditions were optimized, and the specificity, sensitivity, and practicability of LAMP were tested using 47 bacterial strains and simulated contaminated sites.

RESULTSThe results of viable bacterium count showed that LAMP was capable of detecting Vibrio cholerae at a level as low as 1.6x10(2) cfu/ml. The minimal detectable concentration was 1.6+10(3) cfu/ml for simulated contaminated samples such as feces and seawater, and 1.6+10(4) cfu/ml for contaminated milk. All the 21 strains of Vibrio cholerae yielded positive results in LAMP, and the 26 strains of other bacteria all showed negative results, with a detection specificity of 100%.

CONCLUSIONThe established LAMP method has high specificity and sensitivity for detecting Vibrio cholerae and is applicable in field monitoring and epidemiological study of Vibrio cholerae.

Bacterial Proteins ; genetics ; Cholera ; diagnosis ; microbiology ; Clinical Laboratory Techniques ; methods ; Humans ; Nucleic Acid Amplification Techniques ; methods ; Sensitivity and Specificity ; Vibrio cholerae ; genetics ; isolation & purification

OBJECTIVETo investigate the molecular characteristics of phage-type 6b isolates emerging in 1998-2001 cholera epidemics in Sichuan province.

METHODSIsolates were analyzed by phage-typing, pulsed field gel electrophoresis (PFGE) and ompW gene sequencing.

RESULTSAll phage-type 1b and 6b isolates in Sichuan province from 1998 to 2001 were toxigenic. A total of 24 patterns were identified after PFGE analysis, and one predominant pattern consisted of 13 isolates. Several 1b and 6b isolates from Sichuan and isolates of the 1b from other provinces showed the same PFGE pattern. Mutation in ompW gene was found in 6b isolates.

CONCLUSIONV.cholerae O1 6b isolates in Sichuan province from 1998 to 2001 have special genetic markers, and might genetically correlate with contemporaneous 1b isolates.

Bacterial Typing Techniques ; Bacteriophage Typing ; China ; epidemiology ; Cholera ; epidemiology ; microbiology ; DNA, Bacterial ; genetics ; Electrophoresis, Gel, Pulsed-Field ; Genes, Bacterial ; Genotype ; Vibrio cholerae ; classification ; genetics ; isolation & purification