3.Study on the genotype and epidemic characteristics of diarrheagenic Escherichia coli isolated from diarrheal patients in Beijing.
Mei QU ; Xin ZHANG ; Haikun QIAN ; Bing LYU ; Ying HUANG ; Hanqiu YAN ; Zhichao LIANG ; Lei JIA ; Quanyi WANG
Chinese Journal of Epidemiology 2014;35(10):1123-1126
OBJECTIVETo understand the distribution of virulence gene and the epidemiological characteristics of diarrheagenic Escherichia(E.) coli (DEC) from diarrheal patients in Beijing.
METHODSStool specimens from diarrheal patients were cultured which were collected from the hospitals under sentinel surveillance program, during 2012-2013. DNA was examined by real-time PCR.
RESULTS253 out of 6 370 specimens were positive for DEC detection with the rate as 4.0%. A total number of 262 DEC strains were isolated. Two different pathotypes of DEC strains with mixed infection, were isolated from 9 specimens. Different pathotypes would show the following profiles: 42.8% for enteropathogenic E. coli (EPEC) including 42.0% atypical and 0.8% typical; 38.9% for enterotoxigenic E. coli (ETEC) including 24.8% st positive, 9.9% lt positive and 4.2% st and lt both positive;15.3% for enteroaggregative E. coli(EAEC);2.7% for enteroinvasive E. coli (EIEC); one strain STEC with serotype O26:K60. ETEC had obvious characteristics on age. All kinds of DEC were isolated throughout the year with seasonal fluctuation.
CONCLUSIONDEC isolates from diarrheal patients in Beijing were dominated by EPEC and ETEC, with atypical ones accounted for the majority of EPEC. One specimen was found under mixed infection. Pathotypes DEC were found to have different age and seasonal distributions.
China ; epidemiology ; Diarrhea ; microbiology ; Enteropathogenic Escherichia coli ; genetics ; isolation & purification ; Enterotoxigenic Escherichia coli ; genetics ; isolation & purification ; Epidemics ; Escherichia coli ; genetics ; isolation & purification ; Escherichia coli Infections ; epidemiology ; microbiology ; Genotype ; Humans ; Virulence
4.Discovery of new strain of E coli O157: H7 with K antigen.
Xiao-yan ZHEN ; Zhi-yang SHI ; Hua WANG ; Yu-qing LI ; Ling GU ; Xi-ling GUO ; Xian LI ; Zheng-shi YANG
Chinese Journal of Epidemiology 2004;25(8):732-732
5.Risk Factors for Prevalence of EnterotoxigenicEscherichia coli (ETEC) in Diarrheic and Non-diarrheic Neonatal and Weaner Pigs, South Africa.
Samuel T OGUNDARE ; Olubunmi G FASANMI ; Folorunso O FASINA
Biomedical and Environmental Sciences 2018;31(2):149-154
Enterotoxigenic Escherichia coli (ETEC) causes neonatal and post-weaning diarrhea in pigs. In order to determine the risk factors, rectal/fecal swabs and visceral organs obtained from pig farms in two regions of South Africa were analyzed microbiologically against risk variables. Seventy-two percent of young pigs were found to be positive for ETEC toxin genes; estB (38.9%), estB/STAP (25%), and estB/LT (13.9%) were dominant. Risk factors for ETEC-diarrhea in pigs include: leaving sick piglets in a pen with healthy piglets [odds ratio (OR) = 33.52; P < 0.0001]; water spillage in pen (OR = 42.87; P < 0.0001); hypothermic piglets (OR = 7.29; P < 0.0001); runt piglets in pen with healthy littermates (OR = 3.65; P < 0.0001); and prolonged use of antibiotics (OR = 3.05; P = 0.05).
Animals
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Animals, Newborn
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Diarrhea
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epidemiology
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microbiology
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Escherichia coli
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genetics
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isolation & purification
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Escherichia coli Infections
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epidemiology
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microbiology
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veterinary
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Genes, Bacterial
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Prevalence
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Rectum
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microbiology
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Risk Factors
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South Africa
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Swine
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Swine Diseases
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epidemiology
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microbiology
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Weaning
7.Changes of pathogens for nosocomial infection of patients with hematological diseases.
Ji-Jun WANG ; Kai HU ; Zheng-Hui WANG ; Jing WANG ; Hong-Mei JING ; Wei ZHAO ; Yan LIU ; Yu-Ping CHEN ; Xiao-Yan KE
Journal of Experimental Hematology 2010;18(4):1031-1035
In order to investigate the distribution of nosocomial infection in patients with hematological diseases in our hospital, and to explore the changes of the pathogens isolated. The method of retrospective investigation and analysis was employed. 1164 strain pathogens were isolated from the patients with hematological diseases during the period of 1997-2009. The results showed that the Gram-positive cocci infection increased gradually during the 13 years, but has been stable in the last 4 years. The Gram-negative bacteria showed a trend decrease. The fungi increased during these years. The rates of infection with gram-positive cocci, gram-negative bacteria and fungus were 28.2%, 59.8% and 12.0% respectively. For the details, Escherichia coli infection rate was the highest: 12.1%, followed by Pseudomonas aeruginosa (9.1%), Enterobacter (8.4%), Klebsiella pneumoniae (7.4%), Staphylococcus epidermidis (6.3%) and Enterococci (6.6%). The distribution of G(+)- and G⁻ pathogens showed obvious change on end of 1990's and beginning of this century, but it was tending towards stability on recent years; the incidence of fungus was tending towards increase, which was related to wide application of strong broad-spectrum antibiotics. In conclusion, the patients with hematological diseases, as the high-risk group of nosocomial infection, should be monitored strictly. Infection is related to many factors, and the main factor is dysfunction of autoimmunity. The strategies should be explored to strengthen the immune protection and set up a reasonable scheme of antibiotics.
Adult
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Bacterial Infections
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epidemiology
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Cross Infection
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epidemiology
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microbiology
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Escherichia coli
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isolation & purification
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Female
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Gram-Negative Bacterial Infections
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epidemiology
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microbiology
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Gram-Positive Bacterial Infections
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epidemiology
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microbiology
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Hematologic Diseases
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epidemiology
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microbiology
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Humans
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Incidence
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Male
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Middle Aged
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Young Adult
8.All blood, No stool: enterohemorrhagic Escherichia coli O157:H7 infection.
Journal of Veterinary Science 2008;9(3):219-231
Enterohemorrhagic Escherichia coli serotype O157:H7 is a pathotype of diarrheagenic E. coli that produces one or more Shiga toxins, forms a characteristic histopathology described as attaching and effacing lesions, and possesses the large virulence plasmid pO157. The bacterium is recognized worldwide, especially in developed countries, as an emerging food-borne bacterial pathogen, which causes disease in humans and in some animals. Healthy cattle are the principal and natural reservoir of E. coli O157:H7, and most disease outbreaks are, therefore, due to consumption of fecally contaminated bovine foods or dairy products. In this review, we provide a general overview of E. coli O157:H7 infection, especially focusing on the bacterial characteristics rather than on the host responses during infection.
Animals
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Cattle
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Cattle Diseases/blood/epidemiology
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Developing Countries
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*Enterohemorrhagic Escherichia coli
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Escherichia coli Infections/blood/*epidemiology/veterinary
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*Escherichia coli O157/genetics/pathogenicity
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Feces/microbiology
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Hemolytic-Uremic Syndrome/blood/epidemiology/veterinary
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Operon
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Shiga Toxins/analysis
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Shigella dysenteriae
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Virulence
9.Epidemiologic surveillance for bacterial meningitis in 140 000 children under 5 years of age in Nanning district, Guangxi province.
Bai-qing DONG ; Zhen-zhu TANG ; Mei LIN ; Cui-yun LI ; Dong-mei TAN ; Da-bin LIANG ; He-zhuang LIAO ; Xian-zhi LIU ; Yi QUAN ; Jin-song FANG ; Xing-hua WU ; Wei-wen QIN ; P E KILGORE ; W A KENNEDY ; Zhi-yi XU ; J D CLEMENS
Chinese Journal of Epidemiology 2004;25(5):391-395
OBJECTIVETo characterize the incidence, epidemiologic features, etiologic agents and sequelae of bacterial meningitis in children under 5 years of age in Nanning, Guangxi.
METHODSA population-based surveillance was conducted to evaluate children with signs and symptoms of meningitis. All hospitals, township health centers and village clinics in the surveillance area were structured to participate in the case referral and evaluation. Cerebrospinal fluid (CSF) and blood specimens were obtained and processed using standardized microbiologic methods.
RESULTSDuring the 26-month surveillance period, among the children under 5 years old, a total of 1272 cases who met the screening criteria of meningitis were studied. 265 of 1272 cases were identified as clinically diagnosed meningitis, with an incidence rate of 86.36 per 100 000 population. The annual incidence rate under the 38 cases of confirmed bacterial meningitis appeared to be 12.38/100 000. Staphylococcus species accounted for the largest proportion of laboratory-confirmed bacterial meningitis, followed by E. coli and S. pneumoniae. The highest attack rate occurred in neonates < 1 month, followed by children aged 1 - 12 months in the confirmed patients. Meningitis caused by Sp and Hi mainly occurred in children aged 1 - 12 months. All cases of meningitis due to Hi and Sp were children aged 1 - 24 months. 13.16% and 0.00% of the cases survived with complications and sequelae, and the case-fatality rate was 18.42%. 40 bacterial isolates were identified from 1193 blood cultures and 23 from 1211 cerebrospinal fluid samples, but no Neisseria meningitidis was found.
CONCLUSIONMeningitis due to Hi was first confirmed in Guangxi with the incidence of 0.98 per 100 000 population. The annual incidence rate of confirmed bacterial meningitis was 12.38 per 100 000, which was considered an important public health problem in children. Staphylococci was the predominant pathogen in confirmed bacterial meningitis.
Child, Preschool ; China ; epidemiology ; Female ; Humans ; Incidence ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial ; epidemiology ; microbiology ; Meningitis, Escherichia coli ; epidemiology ; Meningitis, Haemophilus ; epidemiology ; Population Surveillance ; Staphylococcal Infections ; epidemiology
10.Pathotyping avian pathogenic Escherichia coli strains in Korea.
Yong Wun JEONG ; Tae Eun KIM ; Jae Hong KIM ; Hyuk Joon KWON
Journal of Veterinary Science 2012;13(2):145-152
To examine the genetic background of avian pathogenic Escherichia coli (APEC) that affects virulence of this microorganism, we characterized the virulence genes of 101 APEC strains isolated from infected chickens between 1985~2005. Serotypes were determined with available anti-sera and median lethal doses were determined in subcutaneously inoculated chicks. The virulence genes we tested included ones encoding type 1 fimbriae (fimC), iron uptake-related (iroN, irp2, iucD, and fyuA), toxins (lt, st, stx1, stx2, and vat), and other factors (tsh, hlyF, ompT, and iss). Twenty-eight strains were found to be O1 (2.0%), O18 (3.0%), O20 (1.0%), O78 (19.8%), and O115 (2.0%) serotypes. The iroN (100%) gene was observed most frequently followed by ompT (94.1%), fimC (90.1%), hlyF (87.1%), iss (78.2%), iucD (73.3%), tsh (61.4%), fyuA (44.6%), and irp2 (43.6%). The strains were negative for all toxin genes except for vat (10.9%). All the strains were classified into 27 molecular pathotypes (MPs). The MP25, MP19, and MP10 pathotypes possessing iroN-fimC-ompT-hlyF-iucD-tsh-iss-irp2-fyuA (22.8%), iroN-fimC-ompT-hlyF-iucD-tsh-iss (21.8%), and iroN-fimC-ompT-hlyF-iss (11.9%) genotypes, respectively, were predominant. Redundancy of iron uptake-related genes was clearly observed and some strains were associated with higher mortality than others. Therefore, strains with the predominant genotypes can be used for diagnosis and vaccine.
Animals
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Bacterial Proteins/genetics/metabolism
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Chickens
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Escherichia coli/*classification/genetics/*pathogenicity
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Escherichia coli Infections/epidemiology/microbiology/*veterinary
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Gene Expression Regulation, Bacterial/physiology
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Phylogeny
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Poultry Diseases/epidemiology/*microbiology
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Republic of Korea/epidemiology
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Virulence