Communicable Disease Control ; Humans ; Research

Animals ; China ; epidemiology ; Humans ; Risk ; Streptococcal Infections ; epidemiology ; microbiology ; pathology ; prevention & control ; Streptococcus suis ; classification ; isolation & purification ; metabolism ; pathogenicity ; Virulence Factors ; metabolism

OBJECTIVE To strengthen the management of earthquake victims with nosocomial infection,in order to prevent and control the multidrug-resistance transmission,and the nosocomial infection outbreak. METHODS All 77 earthquake victims were under real-time monitoring. RESULTS Of 77 cases,53 were infected (69.74%). From 83 samples,83 pathogenic bacteria were isolated. The Gram-positive cocci were 19 (meticillin-resistant Staphylococcus aureus 3,Meticillin-resistant S. epidermidis 7),58 were Gram-negative bacilli (Acinetobacter baumannii 21,multi-drug resistant strains 10,ESBLs positive Escherichia coli 10,Pseudomonas aeruginosa 9) and the fungi were 6 strains,The resistance rates of Gram-positive cocci to penicillin,ampicillin/sulbactam and cefazolin were 89.47%,68.42% and 89.47%; the resistance rates of Gram-negative bacillis to imipenem,cefoperazone/sulbactam,piperacillin/tazobactam,azithromycin,tobramycin,and cefoxitin were 37.93%,60.34%,48.83%,98.28%,98.28% and 70.69%,respectively. CONCLUSIONS Under the situation of higher infection rate and a serious drug resistance in earthquake area,there are no multidrug-resistance transmissionm and the spread of nosocomiol infection outbreak happened in hospital due to strictly enforced prevention meassures and access real-time monitoring and management,

OBJECTIVETo conduct an etiological molecular epidemiological survey and laboratory test on a foodborne disease epidemic outbreak to make clear of the cause and implement effective prevention and control on it.

METHODSOn May 12th 2012, 135 kindergarten children were sent to Xuzhou City People's Hospital and Children's Hospital with gastrointestinal infection disease. A total of 34 anus swab samples and 4 vomit samples were collected from the patients. Real-time PCR rapid detection, strains separation and cultivation, phage lysis experiments, ATB automated identification system were used to make etiological detection and identification. The genomic DNA of salmonella enteritidis were typed with the pulsed-field gel electrophoresis (PFGE), cluster analysis were carried out together with the patterns of local Salmonella infections.

RESULTSChildren in 20 classes were suffered from the gastrointestinal infection among the 21 classes. There were no significant aggregation of class distribution. Among the 135 patients, 76 were boys (56.3%) and 59 were girls (43.7%). The main symptoms were fever (above 38°C), diarrhea and bellyache. Through real-time PCR detection and strains separation, 19 salmonella enteritidis were isolated from 34 anus swab samples of suspected cases and the detection rate was 56%. There were no strains detected from vomit samples. All of the 19 salmonella enteritidis showed the same serological subtype, biochemical reaction, drug sensitivity and phage lysis pattern. The salmonella enteritidis had the identical PFGE pattern (100% similarity), and were different from the pattern of local sporadic infection cases.

CONCLUSIONIt was confirmed that this was an epidemic outbreak of foodborne disease caused by homologous salmonella enteritidis by epidemiological survey, clinical information, lab etiological test and molecular typing.

Bacteriophage Typing ; Child, Preschool ; China ; epidemiology ; Disease Outbreaks ; Electrophoresis, Gel, Pulsed-Field ; Female ; Humans ; Male ; Molecular Epidemiology ; Salmonella Food Poisoning ; epidemiology ; microbiology ; Salmonella enteritidis ; classification ; isolation & purification

OBJECTIVETo understand the variation of Shiga toxin (stx) genes of Escherichia coli O157:H7 strains isolated in China.

METHODSPolymerase chain reaction (PCR) was used to identity the types of stx genes and the nucleotide sequences of the amplified stex variants genes were determined. Compare to the cytotoxicity of Stx,variants were tested by HeLa cell assay.

RESULTSWe found novel stx2 genes in 3 of 289 strains of Shiga toxin-producing E. coli O157:H7 isolated from 1999 to 2002 in China. The novel stx2 genes were inserted by a 1.3-kb insertion sequence (IS) and the nucleotide sequences of IS showed 100% homology with that of IS1203 variant (IS1203v). The IS1203v inserted in the stx2 genes of three E. coli O157:H7 strains at different sites and the direction of the open reading frames (ORFs) of IS1203v of each strain was different. In addition to the above mentioned findings, the nucleotide sequences of three stx2 genes were completely identical and the type of the three Stx2 was Stx2 prototype. Compare to the cytotoxicity of Stx2 prototype, the novel Stx2 was found to be obviously lower.

CONCLUSIONE. coli O157:H7 strains harboring stx2::IS1203v genes were isolated in China. Consequently, the results of HeLa cell assay showed that the insertion of IS1203v could lead to low cytotoxicity of Stx2.

Base Sequence ; China ; DNA, Bacterial ; genetics ; Escherichia coli O157 ; genetics ; isolation & purification ; Genes, Bacterial ; HeLa Cells ; Humans ; Molecular Sequence Data ; Mutagenesis, Insertional ; Polymerase Chain Reaction ; Sequence Analysis, DNA ; Shiga Toxin 2 ; genetics

OBJECTIVETo carry out epidemiological study on an outbreak caused by E. coli O157:H7 infection in Jiangsu province in 1999.

METHODSEpidemiological, microbiological and moleculebiological methods were used to find out the source, route of transmission and risk factors.

RESULTS95 severe O157:H7 infected patients with acute renal failure in 9 counties and districts of 2 municipalities were reported in Jiangsu province, 1999 while 83 of the patients died with a death rate of 87.37%. Most patients were seen in mid or late June. The ratio of male to female was 1 to 1.44 and 88.42% of the patients were over 50 years old. 38 patients occurred in 2000 with 34 deaths. Major factors contributing to the outbreak would include without drinking tap water, eating leftover food, poor sanitary status in kitchen, not washing hands before meal and after bowl movement. 2 strain of O157:H7 was isolated from severe patients and 3 from diarrhea cases. Carrier rate among animals was up to 9.62% and 99.41% of the strains carried toxic gene. Strains isolated from feces of patients and animals belonged to the same colonies.

CONCLUSIONThis outbreak was severe which caused by O157:H7 and was first seen in China, which was closely related to the high carrier rate of O157:H7 in animals and to the positive rate of high toxic gene of the strains. There were various routes of transmission and the main factors of infection would include poor personal health habits and poor sanitation of the household.

Acute Kidney Injury ; epidemiology ; etiology ; Adolescent ; Adult ; Aged ; Aged, 80 and over ; Antibodies, Bacterial ; immunology ; Case-Control Studies ; Child ; Child, Preschool ; China ; epidemiology ; Diarrhea ; epidemiology ; microbiology ; Disease Outbreaks ; Escherichia coli Infections ; complications ; epidemiology ; Escherichia coli O157 ; isolation & purification ; Escherichia coli Proteins ; immunology ; Female ; Hemolysin Proteins ; immunology ; Humans ; Infant ; Male ; Middle Aged ; Seroepidemiologic Studies

OBJECTIVETo analyze the genetic evolution and bacterial type changes of Yersinia enterocolitica in the Ningxia area between year 1984 and 2011.

METHODSA total of 296 strains of Yersinia enterocolitica was collected from diarrhea patients, pig, rodents, sheep and dogs between year 1984 and 2011. The serotype, biotype, ail, ystA, ystB, yadA, virF and other toxic genes were detected. The PFGE subtypes of serotype O:3 and O:9 strains and the cluster features were analyzed.

RESULTSOut of 296 Yersinia enterocolitica strains, pig was the main host, accounting for 65.20% (193/296), followed by rodents, accounting for 32.43% (96/296). Serotype and biotype had their own respective dominant types in different periods. During 1984 and 1985, 2 strains of serotype O:3 and 3 strains of serotype O:9 were isolated, all belonged to biotype 3. Because of lack of strains, there were no obvious dominant types found. Between 1997 and 1999, 177 strains of serotype O:9 Yersinia enterocolitica were isolated as the dominant strain; and there were 178 strains of biotype 2 Yersinia enterocolitica were found. During 2007 and 2011, 54 strains of serotype O:3 Yersinia enterocolitica were isolated as dominant strain; followed by 26 strains of serotype O:5. There were separately 44 and 59 strains of biotype 1A and biotype 3. The PCR test divided the 248 strains into 4 types, including pathogenic strains as type I (ail(+), ystA(+), ystB(-), yadA(+), virF(+)). The PFGE divided the serotype O:3 into 12 types, in which K6GN11C30021 and K6GN11C30012 were the dominant types, accounting for 63.64% (42/66). The serotype O:9 were divided into 14 types, in which K6GN11C90010, K6GN11C90008, K6GN11C30018 and K6GN11C90003 were the dominant types, accounting for 89.01% (162/182).

CONCLUSIONThe different serotypes of isolated strains in Ningxia district showed different dominant bacteria in different periods; while the biotypes also changed with serotypes. The Yersinia enterocolitica isolated from different years showed great variation.

Animals ; DNA, Bacterial ; genetics ; Dogs ; Electrophoresis, Gel, Pulsed-Field ; Genes, Bacterial ; Genetic Variation ; Humans ; Rodentia ; Sheep ; Swine ; Yersinia Infections ; microbiology ; Yersinia enterocolitica ; classification ; genetics ; isolation & purification

OBJECTIVETo analyze the impact of depletion of the twin arginine translocation (TAT) system on virulence and physiology of Yersinia enterocolitica for a better understanding of its pathogenicity.

METHODSWe constructed a DeltatatC::SpR mutant of Yersinia enterocolitica by P1 phage mediated transduction using Escherichia coli K-12 DeltatatC::SpR strain as a donor.

RESULTSA P1-mediated genetic material transfer was found between the two species of enterobacteria, indicating a great potential of acquisition of antibiotic resistance in emergency of a new threatening pathogen by genetic material exchanges. Periplasmic trimethylamine N-oxidase reductase activity was detected in the wild type Y. enterocolitica strain and translocation of this enzyme was completely abolished by the DeltatatC::SpR mutation. In addition, the DeltatatC::SpR mutation showed a pleiotropic effect on the metabolism of Y. enterocolitica. However, the tat mutation did not seem to affect the mobility and virulence of Y. enterocolitica under the conditions used.

CONCLUSIONUnlike other pathogenic bacteria studied, the TAT system of Y. enterocolitica might play an important role in the pathogenic process, which is distinct from other pathogens, such as Pseudomonas aeruginosa and enterohemorrhagic E. coli O157:H7.

Drug Resistance, Microbial ; genetics ; Genes, Bacterial ; Mutation ; Oxidoreductases Acting on CH-NH Group Donors ; metabolism ; Transduction, Genetic ; Virulence ; Yersinia enterocolitica ; enzymology ; genetics ; metabolism ; pathogenicity

OBJECTIVETo identify antigenic proteins secreted by Streptococcus suis (S. suis) type 2 strain SC84.

METHODSTwo-dimensional electrophoresis (2-DE), western-blot assay and matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) analysis were performed to search and identify antigenic proteins secreted by S. suis strain SC84, which triggered an outbreak of the disease in Sichuan province,China, in 2005.

RESULTSA total number of 14 western blot spots were found on PVDF membrane. 11 spots which could be found the existence of matching protein on coomassie G-250-stained 2-DE gel were identified by MALDI-TOF MS. The 11 proteins, all located at extra-cellular or cell wall, were classified into 8 kinds of proteins. Among of them, muramidase-released protein (MRP), suilysin (Sly) and extra-cellular factor (EF) were the known antigenic proteins, but several proteins such as putative 5'-nucleotidase, ribo-nucleases G and E, and predicted metal-loendo-peptidase were newly found antigenic proteins. All the identified protein were found to have had the coding gene in genomic of S. suis strain 05ZYH33, isolated from patients in Sichuan province, China in 2005.

CONCLUSIONThe newly found proteins could be used as voluntary antigens for detection and vaccination of S. suis.

Bacterial Proteins ; analysis ; immunology ; Humans ; Proteomics ; Streptococcal Infections ; Streptococcus suis ; immunology ; isolation & purification ; metabolism

Adult ; Embolism, Paradoxical ; diagnosis ; therapy ; Humans ; Male ; Pulmonary Embolism ; diagnosis ; therapy