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Objective To analyze the serum typing, PFGE molecular typing, and drug-resistance of Shigella strains isolated from the active surveillance for foodborne diseases in Yunnan province from 2016 to 2022, the aim is to understand the pathogen characteristics of Shigella in this period and provide the data support for the control and treatment of Shigella infection. Methods Shigella strains were isolated from the feces of patients between January 2016 and December 2022. Serological typing of the strains was performed using the slide agglutination. Pulsed field gel electrophoresis (PFGE) was employed to detect the molecular typing of the strains. Drug resistance test was achieved by the broth microdilution method. Results A total of 89 Shigella strains were isolated, of which Shigella flexneri accounted for 52.81% and Shigella sonnei 47.19%. Both Shigella flexneri and Shigella sonnei were divided into A and B clusters in PFGE analysis, with B as the predominant cluster. The PFGE bands of 47 Shigella flexneri strains were categorized as 30 types with 3 dominant classes, while 42 Shigella sonnei strains contained 22 types PFGE bands with 4 dominant classes. Two suspected outbreaks were distinguished. Shigella displayed varying degrees of drug resistance to 13 antibiotics, with a 78.65% of multiple resistant strains. Conclusion The dominant PFGE bands of Shigella in Yunnan province were clear, partial of which appeared the clustering distribution. The drug resistance of Shigella was severe and the phenomena of multiple drug resistance were very serious. Drug resistance prototypes between Shigella flexneri and Shigella sonnei were different. [ABSTRACT FROM AUTHOR]

Objective To find out the causes and risk factors of this food-borne disease outbreak that occurred in November 2019 at four schools in Qinzhou, Guangxi, implement effective preventive and control measures to curb the spread and escalation of the outbreak, and provide a basis for the investigation and management of similar incidents in the future. Methods Descriptive epidemiological methods were used to analyze the cases' clinical characteristics, three-dimensional distribution, and related risk factors. The etiological food was determined by the method of analytical epidemiology. A food hygiene investigation was conducted to trace the process of food contamination, and biological samples from cases and workers, suspicious food, and environmental samples were collected for laboratory testing. The detected Salmonella strains were analyzed for homogeneity using pulsed-field gel electrophoresis (PFGE). Results The event involved four schools, with 69 suspected cases identified, resulting inan attack rate of 0.52% (69/13 307). The main clinical symptoms were abdominal pain, diarrhea, and fever, with an average incubation period of 20 hours. The epidemic curve indicated a point-source outbreak. Descriptive epidemiological methods inferred that bakery products distributed by Company F were the suspect foods. The case-control study indicated the risk of illness was increased among those who purchased and consumed food supplied by Company F (OR=37.67, 95%CI: 14.03-101.13), particularly those who consumed the delicious hamburger (OR=30.13, 95%CI: 13.22-68.67). Salmonella Enteritidis (SE) was detected in 12 anal swabsfrom patients, one patient's vomit, one flour sample used for bread-making, and one egg, with homogeneity of 100% achieved in PFGE molecular typing of the 15 positive Salmonella strains. Conclusions The outbreak is a food-borne disease outbreak caused by Salmonella contamination. It is recommended that regulatory authorities strengthen supervision and management of production and processing enterprises, standardize food processing processes, and establish and improve food safety management systems and long-term mechanisms for food safety knowledge promotion and education in schools to enhance students' hygiene awarenessand prevent similar incidents from occurring. [ABSTRACT FROM AUTHOR]

ObjectiveTo investigate the infection status， pathogenic types， antimicrobial resistance and molecular typing of diarrheagenic Escherichia coli （DEC） isolated from patients with foodborne diarrhea in Xi’an City in 2021.MethodsFecal samples from patients with diarrhea were collected from 5 sentinel hospitals for DEC isolation and the pathogenic types of DEC were confirmed via PCR to detect virulence genes. Antimicrobial susceptibility testing and molecular typing were performed using the broth microdilution method and pulsed field gel electrophoresis （PFGE）. The results were statistically analyzed using SPSS software 19.0.ResultsAmong the 389 fecal samples collected from patients with diarrhea， 40 were DEC-positive， with a positivity rate of 10.28%. A total of 41 DEC strains were identified in this study. Enterotoxigenic E. coli （ETEC） and enteroaggregative E. coli （EAEC） were predominant， accounting for 41.46% （17/41） and 39.02% （16/41） of cases， respectively. The gene types estIa/estIb （70.59%， 12/17） and astA/pic （87.50 %， 14/16） were dominant in ETEC and EAEC， respectively. Forty strains （97.56%， 40/41） were resistant to at least one antibiotic， and the resistance rates to ampicillin， tetracycline， cefotaxime， and nalidixic acid were greater than 50%. The multidrug resistance rate was 56.10% （23/41）. Cluster analysis revealed 40 PFGE patterns from the 41 DEC strains. The similarity of these patterns was 62.0%-100.0%.ConclusionThe detection rate of DEC in patients with foodborne diarrhea in Xi’an City in 2021 was relatively high， with the major pathotypes being ETEC and EAEC. The PFGE patterns of the strains were diverse. Finally， the antimicrobial and multidrug resistance of the strains was relatively severe.

Aim This study examined Listeria monocytogenes isolates from two slaughterhouses in Burdur province, southern Turkey, over four seasons for antibiotic resistance, serogroups, virulence genes, in vitro biofilm forming capacity, and genetic relatedness. Methods and results Carcass (540) and environment-equipment surface (180) samples were collected from two slaughterhouses (S1, S2) for 1 year (4 samplings). Of the 89 (12.4%) positive isolates, 48 (53.9%) were from animal carcasses, and 41 (46.1%) from the environment-equipment surfaces. Autumn was the peak season for Listeria monocytogenes compared to summer and spring (P  < 0.05). In addition, the most common serotype between seasons was 1/2c. Except for plcA and luxS genes, all isolates (100%) harbored inlA, inlC, inlJ, hlyA, actA, iap, flaA genes. Listeria monocytogenes isolates were identified as belonging to IIc (1/2c-3c; 68.5%), IVb (4b-4d-4e; 29.2%), and IIa (1/2a-3a; 2.2%) in the screening using multiplex polymerase chain reaction-based serogrouping test. A total of 65 pulsotypes and 13 clusters with at least 80% homology were determined by using pulsed field gel electrophoresis on samples that had been digested with ApaI. Thirty-four (38.2%) of the isolates were not resistant to any of the 14 antibiotics tested. The antibiotic to which the isolates showed the most resistance was rifampicin (44.9%). Serotype 1/2c was the most resistant serotype to antibiotics. Despite having biofilm-associated genes (inlA, inlB, actA, flaA , and luxS), a minority (11%) of isolates formed weak biofilm. Conclusion This study revealed seasonal changes prevalence of Listeria monocytogenes , particularly higher in autumn, posing a greater risk of meat contamination. Notably, Serotype 1/2c showed significant prevalence and antibiotic resistance. Indistinguishable isolates indicated cross-contamination, underscoring the importance of prioritized training for slaughterhouse personnel in sanitation and hygiene protocols. [ABSTRACT FROM AUTHOR]

Copyright of China Tropical Medicine is the property of China Tropical Medicine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ObjectiveThis study aimed to investigate the distribution of virulence genes， antibiotic resistance， and molecular types of diarrheagenic Escherichia coli （DEC） in Wuhan， Hubei Province， China.MethodsDEC strains identified through biochemical means and a time-of-flight mass spectrometer were routinely collected from five medical institutions. Multiple polymerase chain reactions and drug sensitivity tests were carried out. The molecular characteristics of DEC strains were determined using pulsed field gel electrophoresis （PFGE） and multi-locus sequence typing. Homology analysis was carried out based on clustering analogy and the minimum spanning tree.ResultsA total of 59 DEC strains were collected， including 29 strains of enterotoxigenic Escherichia coli （ETEC， 49.15%）， 15 strains of enteroaggregative Escherichia coli （EAEC， 25.42%）， and 15 strains of enteropathogenic Escherichia coli （EPEC， 25.42%）. The resistance rates of DECs to the 11 antibiotics （except polymyxin E） varied， and were especially high for the following： ampicillin （67.80%）， nalidixic acid （61.02%）， tetracycline （45.76%）， cotrimoxazole （37.29%）， cefotaxime （30.51%）， and chloramphenicol （13.56%）. As determined by PFGE， both EAEC and EPEC had 14 different bands， belonging to 11 different sequence types （STs）； whereas ETEC had 28 different bands belonging to 10 different STs. In addition， more than 50% of STs from ETEC were classified as clonal complexes （CC）-10.ConclusionThe contamination of DECs persists in Wuhan， and antimicrobial resistance is at a critical level. The genotypes from EAEC and EPEC are relatively scattered based on molecular detection and typing of DECs. CC-10， the dominant clone complex of ETEC， is widely distributed in Wuhan.

ObjectiveThis study aimed to analyze the relevance ratio and molecular biological characteristics of Listeria monocytogenes （L. monocytogenes） in raw meat sold in Xuzhou city in both 2018 and 2020.MethodsRetail fresh and frozen raw poultry， as well as prepared meat， were randomly sampled from urban areas， and L. monocytogenes were isolated and identified following the guidelines of GB 4789.30-2016. The study analyzed serotypes， drug resistance patterns， virulence genotypes， and molecular typing through pulsed field gel electrophoresis （PFGE）.ResultsOut of 142 raw meat samples collected from the market， 40 tested positive for L. monocytogenes， resulting in a prevalence rate of 28.2% （40/142）. The predominant serotype was 1/2a， accounting for 47.5% （19/40） of the isolates. Molecular typing using PFGE revealed 15 distinct PFGE types among the 40 L. monocytogenes strains. Additionally， 4 strains exhibited resistance to ampicillin， and 2 strains were resistant to penicillin. All strains carried multiple virulence genes.ConclusionThis study highlighted the relatively high contamination of L. monocytogenes in raw meat sold in urban Xuzhou. The presence of small-scale homologous strains emphasizes the importance of enhanced monitoring and management to prevent foodborne diseases.

ObjectiveTo investigate the contamination， molecular typing characteristics， and drug resistance of Cronobacter in cereal-based infant food in Taizhou.MethodsAll samples were detected qualitatively and quantitatively according to GB 4789.40—2016. Isolated strains were typed using pulse field gel electrophoresis （PFGE）， and antibiotic susceptibility tests were performed using the micro-broth dilution method.ResultsForty-one strains were isolated from 335 samples. The total detection rate was 12.2%， and the quantitative results were 0.36-7.5 MPN/100 g. The cooked sample （46.9%） had the highest detection rate among edible samples， and the sample purchased online （24.0%） had the highest detection rate among purchased samples. Forty-one strains were divided into 34 PFGE patterns with similarity rates of 45.1%-100.0%， and some strains from different enterprises or different branches of one enterprise belonged to the same clone. Their insensitivity rates to cefazolin and nitrofurantoin were 48.8% and 39.0%， respectively， and 9 strains were insensitive to both.ConclusionSome cereal-based supplementary foods for infants were contaminated with Cronobacter in Taizhou. It is necessary to pay attention to the risk of Cronobacter infection in infants caused by cooked food and food purchased online.

ObjectiveTo provide basic data for modification of laboratory testing for outbreaks caused by Clostridium perfringens （C. perfringens）， a diarrhea outbreak that may have been caused by polyclonal infection of C. perfringens was analyzed.MethodsAnal swab samples of 4 patients with diarrhea were collected. cpa and cpe genes and C. perfringens in original swab samples and enriched samples were detected via real time PCR. Toxin gene test and pulsed field gel electrophoresis （PFGE） were performed for some C. perfringens isolates.Resultscpa and cpe genes were positive in samples of 4 patients. One cpe+ isolate was obtained from 18 isolates of C. perfringens from patient 1， and the composition ratio was 5.56% （1/18）. One cpe+ isolate was obtained from 6 isolates of C. perfringens in patient 2， and the composition ratio was 16.7% （1/6）. No cpe+ isolate was obtained from patient 3， and C. perfringens was not isolated from patient 4. Two types （A type and C type） and 5 PFGE patterns were identified in 11 isolates of C. perfringens. Two cpe+ isolates from patient 1 and patient 2 had identical PFGE patterns.ConclusionThis outbreak might have been caused by C. perfringens. Considering the delays caused by the implementation of diagnostic standards， comprehensive use of laboratory detection methods can improve the response time of outbreak analysis.

ObjectiveTo analyze the pathogenic characteristics of Salmonella senftenberg isolate causing food poisoning in Xinxiang in 2021.MethodsEpidemiological investigation of food poisoning event was performed. Pathogenic bacteria were separated and identified from 11 samples. Ten Salmonella isolates were subjected to serotyping， drug susceptibility testing， detection of characteristic gene fragments （mogA， sseL， mgtC， bcfA， araB） of 5 virulence island （SPIs） and pulsed field gel electrophoresis （PFGE） typing analysis.ResultsSerum antigenic formulas of all Salmonella isolates were 1，3，19；g，s，t Salmonella senftenberg. All Salmonella isolates were resistant to cefazolin， kanamycin， gentamicin and amikacin. Among them， two isolates from the patient feces were also resistant to ampicillin， tetracycline，doxycycline，chloramphenicol，trimethoprim/sulfamethoxazole. PFGE clustering analysis showed that there was no difference in the bands among the 10 strains （2 cases strains， 5 food strains， and 3 environmental strains）， suggesting that they were highly homologous. Five Salmonella pathogenicity island characteristic gene fragments were detected among 10 isolates.ConclusionSalmonella senftenberg caused the food poisoning event. The isolates carried 5 Salmonella pathogenicity island characteristic gene fragments and 2 isolates exhibited multi-drug resistance. Relevant departments should pay more attention to this issue.

ObjectiveTo investigate the serotype， cholera toxin encoding gene （ctxAB） carying rate， antibiotic resistance and molecular typing of Vibrio cholerae in Shaoxing from 2020 to 2021.MethodsSixty-eight strains were isolated from aquatic products and feces of patients with diarrhea from 2020 to 2021， and serologically classified by glass agglutination method. The ctxAB gene was detected by real-time fluorescence polymerase chain reaction. Microbroth dilution method and pulsed field gel electrophoresis （PFGE） were used for antibiotic sensitivity test and molecular typing of strains， respectively.ResultsOnly three of the 68 strains were O1 serotype Ogawa， and the other 65 strains were non-O1/O139 serogroup. All strains did not detected ctxAB gene. The antibiotic resistance rates to ceftazidime， ceftazidime/avibactam and cotrimoxazole were 45.6%， 38.2% and 36.8%， respectively. All strains were sensitive to tetracycline， tigecycline， azithromycin and amikacin， and 17 strains were resistant to 3 or more antibiotics. PFGE molecular typing of strains digested by Not I showed diversity， and there was a great difference between the aquatic product isolates and the case isolates.ConclusionThe main serogroup of Vibrio cholerae was non-O1/O139 in Shaoxing from 2020 to 2021. The strains did not carry ctxAB gene and were resistant to multiple antibiotics. The molecular characteristics of strains were complex and diverse.

Objective: To explore the carrying status and homology of carbapenem resistant Acinetobacter baumannii (CRAB) in our hospital. Methods: From January 2015 to December 2017, 52 strains of acinetobacter baumannii isolated from the bacteria room of the clinical laboratory of Baogang hospital in Inner Mongolia were selected as the research object. KB disk diffusion method and Vitek-2 were used to determine the drug sensitivity of Acinetobacter baumannii. The drug resistance gene was detected by polymerase chain reaction (PCR) and its homology was analyzed by pulsed field gel electrophoresis (PFGE). Results: Except for Cefoperazone/sulbactam, other antibiotics were resistant to ab. The detection rate of drug resistance gene class C b-lactamases (ADC) was 100%, and the higher detection rates of other drug resistance genes were class D b-lactamases (OXA)-51 (36 strains, 90.0%), disinfectant gene qacE1-sull (32 strains, 80.0%), and klebsiella pneumoniae carbapenemase (KPC) gene was not detected. 2-8 drug resistance genes were detected in each CRAB strain, and the strains with 6 drug resistance genes were the most (15 strains, 37.5%); Among the detected drug-resistant gene combinations, ADC+OXA-23 + OXA-51 gene was detected at the same time (29 strains, 72.5%), followed by ADC+ intl1 + qacE1-sull gene (26 strains, 65.0%), ADC + qacE 1-sull + ant (3") -i gene (19 strains, 47.5%), and 11 strains (27.5%). There were 19 different types in PFGE homology test, each type was 1-9 strains, including 9 strains of A5 type and 8 strains of A18 type, mainly from intensive care unit. Conclusion: CRAB in the hospital is highly resistant to common clinical antibiotics. OXA-23 and OXA-51 genes are most likely to be the main factors causing drug resistance of Acinetobacter baumannii in the hospital. Homology analysis showed that there was CRAB nosocomial infection transmission in different wards of the hospital. [ABSTRACT FROM AUTHOR]

ObjectiveTo determine the drug resistance， main virulence genes and molecular typing of Vibrio parahaemolyticus from multiple sources in Fengxian District， Shanghai.MethodsA total of 210 strains of Vibrio parahaemolyticus were isolated in Fengxian District， Shanghai， from 2018 to 2020. Then drug susceptibility tests of 17 antibiotics， virulence gene detection of thermolabilehemolysin （tlh）， thermostable direct hemolysin （tdh） and thermostable direct hemolysin-relatedhemolysin （trh）， and pulsed-field gel electrophoresis （PFGE） were conducted.ResultsA total of 147 drug-resistant strains were detected， with the drug resistance of 70.00%. Among them， 126 strains were resistant to single antibiotic， mainly resistant to CFZ； 15 strains were resistant to two antibiotics， mainly resistant to CFZ and AMP； and 6 strains of MDR， mainly resistant to AMP， SXT， CFZ， CTX， CAZ and FEP. The AMP resistance of food-borne strains was higher than that of human-derived strains （P

Understanding the plasticity of genomes has been greatly aided by assays for recombination, repair and mutagenesis. These assays have been developed in microbial systems that provide the advantages of genetic and molecular reporters that can readily be manipulated. Cellular assays comprise genetic, molecular, and cytological reporters. The assays are powerful tools but each comes with its particular advantages and limitations. Here the most commonly used assays are reviewed, discussed, and presented as the guidelines for future studies.

ObjectiveTo determine the pathogenic cause in a foodborne diseases outbreak of Salmonella enteritidis in a company in Suzhou City， and provide evidence for epidemiological investigation and guidance for clinical treatment.MethodsRelevant specimens were examined for Salmonella， Shigella， Staphylococcus aureus and Vibrio parahaemolyticus. Furthermore， for the isolated Salmonella enteritidis， a micro broth dilution method was used for antimicrobial susceptibility testing， and pulsed field gel electrophoresis （PFGE） was used for molecular typing.ResultsA total of 44 strains of Salmonella enteritidis were detected from 43 anal swabs of the patients in the outbreak， 7 anal swabs of canteen employees， 31 retained food specimens and 6 environmental specimens. A total of 15 antimicrobial susceptibility testings showed that the 44 strains had the same antimicrobial resistance spectrum， which was 100% resistant to cefazolin， ampicillin， ampicillin/sulbactam， polymyxin E and nalidixic acid， suggesting a multi-drug resistance to more than three antibiotics. PFGE cluster analysis showed that the 44 strains had a 100% of genetic similarity.ConclusionThe outbreak is caused by the consumption of food contaminated with Salmonella enteritidis. The isolated strains have multi-drug resistance， which could guide appropriate antimicrobial treatment based on the antimicrobial susceptibility testing.

ObjectiveTo explore the carrying status and homology of carbapenem resistant Acinetobacter baumannii (CRAB) in our hospital.MethodsFrom January 2015 to December 2017, 52 strains of acinetobacter baumannii isolated from the bacteria room of the clinical laboratory of Baogang hospital in Inner Mongolia were selected as the research object. K-B disk diffusion method and Vitek-2 were used to determine the drug sensitivity of Acinetobacter baumannii. The drug resistance gene was detected by polymerase chain reaction (PCR) and its homology was analyzed by pulsed field gel electrophoresis (PFGE).ResultsExcept for Cefoperazone/sulbactam, other antibiotics were resistant to ab. The detection rate of drug resistance gene class C β-lactamases (ADC) was 100%, and the higher detection rates of other drug resistance genes were class D β-lactamases (OXA)-51 (36 strains, 90.0%),disinfectant gene qacE△1-sull (32 strains, 80.0%), and klebsiella pneumoniae carbapenemase (KPC) gene was not detected. 2-8 drug resistance genes were detected in each CRAB strain, and the strains with 6 drug resistance genes were the most (15 strains, 37.5%); Among the detected drug-resistant gene combinations, ADC+OXA-23 + OXA-51 gene was detected at the same time (29 strains, 72.5%), followed by ADC+ intl1 + qacE △ 1-sull gene (26 strains, 65.0%), ADC + qacE △ 1-sull + ant (3 ‘‘) -i gene (19 strains, 47.5%), and 11 strains (27.5%). There were 19 different types in PFGE homology test, each type was 1-9 strains, including 9 strains of A5 type and 8 strains of A18 type, mainly from intensive care unit.ConclusionCRAB in the hospital is highly resistant to common clinical antibiotics. OXA-23 and OXA-51 genes are most likely to be the main factors causing drug resistance of Acinetobacter baumannii in the hospital. Homology analysis showed that there was CRAB nosocomial infection transmission in different wards of the hospital.

In this study, Salmonella Enteritidis strains isolated from dust and environmental materials from different flocks located in Turkey’s Western Black Sea region were examined by pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). A total of 59 S. Enteritidis strains isolated from broiler breeder and hatchery flocks, and one S. Enteritidis strain isolated from a stool sample of a farm worker were examined. PFGE analysis revealed two major PFGE groups and nine different macro restriction profiles. It was determined that 85% (51/60) of the strains were close to each other and comprised Group I. All S. Enteritidis strains had the same sequence type (ST): ST11. Isolation of strains with a single genotype suggests that there may be a cross transmission between the flocks.

Copyright of Saudi Medical Journal is the property of Saudi Medical Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ObjectiveEstablishing the database of food-borne Salmonella typhimurium 1, 4, [5], 12∶i∶- and monophasic variant in Guangxi Zhuang Autonomous Region by investigating the drug resistance and molecular typing characteristics of the isolates in 2018.Methods124 strains of S. 1, 4, [5], 12∶i∶- from clinic samples and food samples were tested for drug sensitivity by minimum inhibitory concentration (MIC), and molecular typing by pulsed field gel electrophoresis (PFGE).ResultsOne hundred and twenty four strains of S. 1, 4, [5], 12∶i∶- were all sensitive to imipenem, but resistant to the other 13 antibiotics at different levels. The resistance rate to tetracycline was the highest (96.8%, 120/124), followed by ampicillin (95.2%, 118/124). Multidrug resistant (MDR) rate was 26.6% (33/124), and 47.1% S. 1, 4, [5], 12∶i∶- isolates were multi-resistant to ACSuT. The S. 1, 4, [5], 12∶i∶- strains were differentiated into 104 Xba I PFGE patterns with similarity of 72.9%-100%, and the dominant patterns were JPXX01.GX0114 (5 isolates) and JPXX01.GX0294 (4 isolates), all of which came from foodborne disease surveillance.ConclusionThe result indicated that the S. 1, 4, [5], 12∶i∶- isolates in Guangxi were highly resistant to penicillins and tetracyclines and drug resistance situation was not optimistic, S. 1, 4, [5], 12∶i∶- PFGE pattern were highly sporadic. It is necessary to trace the molecular origin of the isolated strains on time, which can improve ability to identify potential food-borne S. 1, 4, [5], 12∶i∶- outbreak events in sporadic cases.

ObjectiveTo identify the suspected food, pathogenic factors and risk factors of the foodborne disease outbreak in a school, and to provide reference for the prevention, control and investigation of similar events in the future.MethodsDescriptive epidemiological method were used to analyze the clinical characteristics, epidemiological characteristics and related risk factors of the cases. Suspicious meals and food were identified by case-control study. Samples such as anal swabs of cases and kitchen workers, reserved food and environment were collected for etiological detection. Salmonella isolates were classified by pulsed field gel electrophoresis.ResultsA total of 74 cases were found, with an incidence rate of 1.9%. The main clinical symptoms were diarrhea (83.8%), abdominal pain (78.4%) and fever (63.5%). The prevalence curve showed intermittent homologous exposure, and the distribution of cases in classes and dormitories showed no obvious aggregation. Results of a case-control study showed the risk factor was the rice with scrambled egg from the second dining hall (October 8 OR=7.00, 95% CI: 1.51~32.48; October 9 OR=262.50, 95% CI: 22.21~3 102.06). A total of 76 samples were collected, 12 of which were isolated and cultured for Salmonella enteritidis. There are two zonal types with similarity of 95.7% by PFGE analysis.ConclusionThis incident was a foodborne disease outbreak caused by Salmonella enteritidis, and suspected food was the rice with scrambled egg. Food hygiene supervision should be strengthen in schools and other collective units, and food with eggs should be thoroughly cooked.

ObjectiveTo understand the molecular epidemiology and antimicrobial resistance pattern of clinically isolated Salmonella in Shaoxing city from 2017 to 2019.MethodsThe 245 Salmonella strains that were isolated from foodborne disease and diarrhea cases in Shaoxing were collected and serotyped. Broth microdilution method was performed to carry out drug resistance testing. Pulsed field gel electrophoresis (PFGE) and BioNumerics V7.1 software were applied to clustering analysis.ResultsThe 245 isolates of Salmonella were composed of sixty serotypes. The predominant serovars were Salmonella typhimurium (32.24%), Salmonella enteritidis (10.20%) and Salmonella london (6.94%). The 225 strains were resistant to 25 antibiotics at different degrees. Among these isolates, higher rates of resistance to ampicillin (77.14%), tetracycline (73.88%) and streptomycin (66.53%) were found and the multiple drug resistance rate reached 76.33%. On the other hand, the predominant serovars were digested with Xba Ⅰ, which contained 48, 11 and 12 different PFGE fingerprints, respectively.ConclusionSalmonella serotypes and PFGE fingerprints were highly diverse. Antibiotic resistance was concentrated in AMP-TET-STR.

ObjectiveTo investigate and trace the source of Salmonella enteritidis food poisoning in a welfare institution, so as to provide reference for the study of similar foodborne disease.MethodsEpidemiology, food hygiene and pulsed field gel electrophoresis (PFGE) technology were used to investigate and analyze the incident.ResultsThere were 23 confirmed cases of foodborne disease, and the incidence rate was 5.65% (23/407); 15 anal swabs were collected from patients, as well as 3 anal swabs from kitchen staff, 3 preserved dishes, 2 fruits and 1 cold drink. Salmonella enteritidis was detected from 11 anal swabs. PFGE typing result showed that the similarity of 11 strains of Salmonella enteritidis was 96.4%, and cluster analysis showed that they were the same type. It was preliminarily determined that the strain was from the same clone line.ConclusionBased on the analysis of epidemiology, food hygiene and laboratory test result, it was confirmed that the foodborne disease was caused by Salmonella enteritidis. Welfare institutions should strengthen the management of food safety for special groups, and formulate corresponding emergency response plans for food poisoning emergencies to prevent the recurrence of such accidents.

ObjectiveIn order to discover the pulsed field gel electrophoresis (PFGE) serotypes and drug resistance of Salmonella agona (S. agona) in Sichuan Province during 2008 to 2018, so as to understand the contamination status of S. agona and provide reference data for outbreak warning, traceability investigation and antibiotic use strategy.MethodsA total of 61 S. agona strains after the serological and biochemical identification were analyzed by PFGE and tested for minimal inhibitory concentration of 14 antibiotics.ResultsThe isolates of S. agona were divided into 41 PFGE types, some strains isolated from clinical cases in different years and regions had the same PFGE type, one pork isolate had the same PFGE type as some clinical isolates. The antibiotic resistance test indicated 28 of the isolates were sensitive to 14 kinds of antibiotics, the other 33 strains showed different degrees of drug resistance, nearly half of the strains were insensitive to tetracycline; and there were 16 multidrug-resistant strains. All of the isolates were sensitive to imipenem.ConclusionThe PFGE types of S. agona isolated in Sichuan from 2008 to 2018 showed diversity, and they were sporadic prevalent in Sichuan Province. The drug resistance was serious with an increasing trend.

ObjectiveTo analyze the etiological characteristics of strains isolated from Vibrio parahaemolyticus food poisoning incidents occurred in Zibo in 2019.MethodsSerotyping and virulent genes (tlh, tdh, trh)were detected by real-time fluorescent polymerase chain reaction, antibiotic sensitivity was examined by broth microdilution method and pulsed field gel electrophoresis (PFGE) were applied to Vibrio parahaemolyticus.ResultsThe 9 strains collected from patients were all pandemic O3∶K6, and the virulence genes were tlh+ tdh+ trh-. The 2 strains collected from environmental samples were O8∶K22 and O1∶K32, and the virulence genes were all tlh+ tdh-trh-. All strains were resistant to cefazolin, and partially resistant to ampicillin and trimethoprim/sulfametho-xazole. There were 2 strains even showed multiple resistance to these three antibiotics, while all strains were sensitive to the other antibiotics. The PFGE homology from the same incident was high.ConclusionThe strains collected from patients in the 4 incidents were all pandemic O3∶K6 and the virulence genes were tdh+, some of which showed multi-antibiotic resistance, and the isolates from the same outbreak had high homology suggesting that they had been exposed to the same pollution source. The supervision of pollution sources should be strengthened to reduce the occurrence of foodborne diseases.

ObjectiveTo investigate the etiology of a small outbreak of gastroenteritis caused by Vibrio parahaemolyticus in Guangzhou, 2017.MethodsSerotype identification, antimicrobial susceptibility test, polymerase chain reaction (PCR) test of virulence genes (tdh, trh, tlh), toxRS/new gene, orf8 gene, pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were analyzed.ResultsThe serotype O8∶K21 was identified. All isolates were sensitive to ceftriaxone, ciprofloxacin, chloramphenicol, cotrimoxazole, sulfonamide complex, amikacin, nalidixic acid, streptomycin, tetracycline and gentamicin, and resistant to ampicillin and trimethoprim. The PCR detection of virulence gene showed that all the strains were positive for tdh (thermostable direct hemolysin) and tlh (themolabile hemolysin), but negative for trh (tdh-related hemolysin), and carried toxRS/new and orf8 genes. According to PFGE cluster analysis, they were considered to be a highly related strains. According to MLST analysis, the results were all ST479 type.ConclusionThe reason for the small outbreak of gastroenteritis was due to Vibrio parahaemolyticus O8∶K21, which shared common genetic characteristics. It harbored the tdh gene which was the key characteristic of pandemic strains, and additional surveillance should be conducted to facilitate control of the transmission of this pathogen.

Objective To put forward preventive and control measures for the quality control of pre-packed cooked meat products by investigating the contamination of Listeria monocytogenes during the food processing chain, analyzing of the molecular characteristics and antibiotic susceptibility of Listeria monocytogenes isolates. Methods Four hundred and sixty samples of raw materials, intermediate products, finished products, final products and environmental samples were collected from a pre-packed cooked meat factory in Dezhou during 2015 to 2017. All samples were tested for Listeria monocytogenes based on GB 4789.30-2016. Pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were applied to identify molecular types of Listeria monocytogenes isolates. The antibiotic resistance test on 8 antibiotics was performed by broth microdilution susceptibility test. Results The detection rate of Listeria monocytogenes in 460 samples was 17.61% (81/460) . The detection rate in 2016 was the highest(22.40%, 41/183) and that from different years was statistically different (χ2=7.28, P

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To understand the drug resistance and molecular typing characteristics of 54 strains of Salmonella Typhimurium in Xindu District from 2014 to 2019. Methods The 54 strains of Salmonella Typhimurium isolated from case monitoring, food poisoning and food surveillance were tested for drug susceptibility using micro-broth dilution method, and pulsed field gel electrophoresis(PFGE) was used for molecular typing. Results The drug resistance rate of 54 strains of Salmonella Typhimurium was 98.15%(53/54), and that of multi-drug resistance(triple and above) was 46.30% (25/54). The multi-drug resistance rates of the case monitoring and food surveillance strains were 56. 00%(14/25) and 91.67%(11/12), respectively, which were much higher than the food poisoning strains 0.00%(0/17). The PFGE results could be divided into 31 pattern, with a similarity of 64.9%-100%. Among them, the dominant pattern was XD005, which contains 7 strains isolated from case monitoring and food surveillance. The results of drug resistance and molecular typing of strains from food poisoning were significantly different from those from case monitoring and food surveillance(P

Objective To analyze the serotypes and molecular type of Listeria monocytogenes strains isolated from food, clinical case and environment in Fujian Province, so as to provide reference for the outbreak identification and traceability of foodborne diseases. Methods Using multiplex polymerase chain reaction (PCR) serotyping, immune serum agglutination and pulsed field gel electrophoresis (PFGE) to classify the strains. Results The 117 strains of Listeria monocytogenes strains were divided into 4 PCR serotypes, 67.5% (79/117) of which were 1/2a (3a), 23.1% (27/117) were 1/2b (3b), 5.1% (6/117) were 1/2c (3c) and 4.3% (5/117) were 4b (4d, 4e). Among the 9 strains isolated from cases, 6 strains were 1/2a, 2 strains were 4b and 1 strain was 1/2b. 117 Listeria monocytogenes strains were divided into 83 different PFGE types by Asc I restriction endonucleases, and 10 strains of which had unique and single types. Nine clinical case isolates were divided into 8 different PFGE types. Conclusion 1/2a serotype was dominant in Listeria monocytogenes isolated from food and clinical specimens in Fujian Province, and 4b serotype should be concerned.

Objective To investigate a food poisoning events occurred in multiple schools at the same time, and analyze pathogenic factor, contaminated food and source, in order to guide clinical treatment and preventive measures. Methods Based on the investigation of clinical characteristics and epidemiological distribution of patients, homology analysis of Salmonella from different sources was carried out with the combination of pulsed field gel electrophoresis (PFGE) in the laboratory. Results Totally 37 suspected cases were found from 4 school in different districts, 19 cases were diagnosed. The main clinical features of the patients were diarrhea (70.27%, 26/37), fever (54.05%, 20/37), abdominal pain (51.35%,19/37) and vomiting (37.84%, 17/37). A total of 24 strains of Salmonella Enteritidis were isolated in the laboratory, of which 19 strains were from cases and 5 strains were from sandwiches and their dried meat floss. According to PFGE, 24 strains of Salmonella Enteritidis were clustered to 100.00%. The drug resistance rate of 19 cases was 100.00% to nalidixic acid and 5.26% (1/19) to cefoxitin and imipenem. Conclusion Combined with the clinical feature, epidemiological investigation and laboratory test results, it was confirmed that the main cause of the incident was the raw material of the sandwich which was contaminated by Salmonella Enteritidis. It is suggested that the regulatory department should strengthen the supervision of the school catering company, improve the food safety awareness and prevent the foodborne disease.

Objective To investigate the infectious status, virulence gene, molecular typing and antibiotic resistance of diarrheogenic Escherichia coli (DEC) in sentinel hospitals of Fujian Province in 2019. Methods Fluorescent polymerase chain reaction (PCR) was used to identify 210 fecal samples of diarrhea patients after isolation of E. coli according to GB 4789. 6-2016, and then pulsed field gel electrophoresis (PFGE) molecular traceability and antibiotic resistance test were conducted on the isolated DEC. Results Thirty two strains of bacteria were detected, with a detection rate of 15.2% (32/210). Among them, enteropathogenic E. coli (EPEC) accounted for 37.5% (12/32), enteroaggregative E. coli (EAEC) for 37.5% (12/32), and enterotoxigenic E. coli (ETEC) for 25.0% (8/32). The results of antibiotic resistance test showed that these 32 strains of bacteria were most resistant to ampicillin, with a resistance rate of 78.1% (25/32), followed by tetracycline and trimethoprim/sulfamethoxazole, with resistance rates of 62.5% (20/32) and 59.4% (19/32), respectively. The multiple antibiotic resistance rate was 50.0% (16/32). The results of PFGE showed that 32 strains of bacteria causing diarrhea were divided into 28 PFGE banding patterns. Among them, 12 strains of EPEC and 12 strains of EAEC were divided into 10 PFGE banding patterns, respectively, and 8 strains of ETEC were divided into 8 PFGE banding patterns. The results of cluster analysis showed that two groups of EPEC strains had 100.0% similar banding patterns, one group of EAEC strains had 100.0% similar banding patterns, and ETEC strains did not have completely consistent banding pattern. Conclusion EPEC and EAEC were the main pathogens of diarrhea in surveillance points of Fujian Province in 2019. The genetic diversity of the strains showed that the genetic relationship between them was relatively distant. The antibiotic resistance of DEC was severe, and the rate of multiple antibiotic resistance was high.

The article describes the occurrence and phylogenetic relationship of Salmonella isolates found in subcutaneous abscesses of leopard geckos. The aim of the study was to determine the cause of the abscesses and to characterise isolated Salmonella strains.

Objective To investigate the pathogenic characteristics of Clostridium perfringens isolated from two diarrhea outbreaks. Methods Samples and specimens of patients, chefs, cooking utensils and suspicious foods involved in 2 diarrhea outbreaks were collected. The real-time polymerase chain reaction (PCR), bacteria isolation and culture were performed on the samples. The number of CPs in the specimens was counted. Toxicity genes, pulsed-field gel electrophoresis (PFGE) and drug resistance detection were performed on the isolated CP strains. Results After real-time PCR and bacterial isolation, CP was detected in some patients specimens, food and smear samples, and other common viruses and bacteria were negative. In most cases, the CP count of the specimens exceeded 1.0 × 106 CFU/g. The 10 strains of CP isolated were all carrying toxin-producing genes. The PFGE fingerprints of the 10 strains were divided into 7 bands, of which 3 were the same band in the first outbreak, and 2 bands were the same in the second outbreak. Those strains were sensitive to imipenem, metronidazole, ceftriaxone and penicillin. Six strains were resistant to clindamycin, one strain was intermediated, and six strains were intermediated to chloramphenicol. Conclusion PCR could be used for rapid screening of CP virulence genes. PFGE could also help determine food poisoning events caused by CP. At the same time, the daily monitoring of CP and the prevention of its drug resistance should be strengthened.

Objective To study the distribution, virulence genes, drug sensitivity and molecular characteristic of Bacillus cereus in five foods in Haikou area. Methods The Bacillus cereus strains were isolated from different foods including pastries, milk powder, fast food, Hainan rice noodles and its ingredients, collected from Haikou area, according to the standard GB 4789.14-2014. The specific gene groEL and 10 virulence genes were detected by general polymerase chain reaction (PCR) method. The sensitivity to antibiotics of isolates was performed with minimum inhibitory concentration (MIC). The pulsed field gel electrophoresis (PFGE) patterns of strains were analyzed. Results 197 strains of B. cereus were isolated from 626 food samples and the positive rate of B. cereus was 31.5%. In particular, most of B. cereus strains were isolated from Hainan rice noodles, accounting for 63.1% (140/222). All isolates carried at least one virulence gene, the rate of entFMgene was the highest, up to 99.0% (195/197). On the contrary, ces gene was the lowest at 2.5% (5/197) only. There were 175 (88.8%) strains that carried genes of nheA, nheB and nheC simultaneously. There were 27 (13.7%) strains that carried genes of hblA, hblC and hblD simultaneously. The sensitive rate of strains towards gentamicin, chloramphenicol, vancomycin and ciprofloxacin were 100.0% (197/197), 100.0% (197/197), 99.5% (196/197) and 92.9% (183/197), respectively. And the resistance rate of strains towards penicillin and trimethoprim-sulfamethoxazole were 100.0% (197/197) and 90.9% (179/197), respectively. The PFGE result showed 30 clusters and 117 genotypes. Conclusion The positive rate of Bacillus cereus in five foods in Haikou area was relatively high, especially in Hainan rice noodles, which should arouse attention and close observation. Targeted prevention and control measures can be carried out according to the characteristics of virulence genes, molecular typing and antibiotic sensitivity of the strains.

Hospital infections are of great relevance in human and animal health, and fomites are important in the spread of pathogens in hospital units. The aim of this study was to investigate the frequency of enterobacteria in the operating room of a veterinary hospital, the potential cross-contamination of samples, and to characterise the susceptibility profile of the isolates to antimicrobials. Sixty-five samples were collected from five different surgical procedures. These samples came from the hands and cell phones of the surgical team and pet owners, operating tables, and patients. Species detection was performed through polymerase chain reaction, genetic diversity by pulsed-field gel electrophoresis (PFGE), and susceptibility to antimicrobials through an antibiogram. Escherichia coli and Proteus mirabilis isolates were obtained from eight samples, from the hands of the anaesthesiologist, the pet owner, and the surgeon; the surgeon's, the nurse's and the anaesthesiologist's cell phones, and two surgical tables. Furthermore, PFGE showed high genetic diversity among the isolates, which showed multidrug resistance. The identification of multidrug-resistant E. coli and P. mirabilis on cell phones of the surgical team is a major concern and, although no direct correlation was found, the isolation of these bacteria inside the clean area of the operating room shows the possibility of nosocomial transmission from cell phones to susceptible patients. [ABSTRACT FROM AUTHOR]

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Objective: To study and analyze the drug resistance spectrum and molecular typing of Stenotrophomonas maltophilia in hospital infection, so as to provide basis for making reasonable infection control plan. Method: 42 strains of clinical isolates of Stenotrophomonas maltophilia were identified by mass spectrometer and their drug resistance phenotypes were analyzed. According to the different groups of drug sensitivity results of five antibiotics, ceftazidime, compound neoformamine, levofloxacin, minocycline and cefepime, the strains with the same drug sensitivity results were divided into one type and the strains with different drug sensitivity results were divided into another type; PFGE was used for molecular typing Analysis. Results: 42 strains of Stenotrophomonas maltophilia were divided into 6 types. 42 strains of Stenotrophomonas maltophilia were analyzed by PFGE and 4 genotypes of A-D were obtained. Conclusion: The characteristics of drug resistance spectrum and PFGE typing of Stenotrophomonas maltophilia are very useful for the selective treatment of antibiotics. [ABSTRACT FROM AUTHOR]

Zeqiang Zhan,1 Xuebin Xu,2 Zhen Gu,3 Jianghong Meng,4 Xiayidan Wufuer,5 Mingliu Wang,6 Meilian Huang,7 Jianhui Chen,8 Chunmei Jing,9 Zhiying Xiong,1 Mei Zeng,10 Ming Liao,1 Jianmin Zhang1 1National and Regional Joint Engineering Laboratory for Medicament of Zoonoses Prevention and Control, Key Laboratory of Zoonoses, Ministry of Agriculture, Key Laboratory of Zoonoses Prevention and Control of Guangdong Province, Animal Infectious Diseases Laboratory, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China; 2Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China; 3Emerging Infections Program China Office, Beijing, 102206, China; 4Department of Food Science and Nutrition, University of Maryland, College Park, Maryland 20742, USA; 5Xinjiang Uygur Autonomous Region Center for Disease Control and Prevention, Urumchi 830001, China; 6Guangxi Zhuang Autonomous Region Disease Prevention and Control Center, Nanning 530028, China; 7Xiamen City Children’s Hospital, Xiamen 361006, China; 8Fujian Provincial Center for Disease Control and Prevention, Fuzhou 350001, China; 9Chongqing City Children’s Hospital, Chongqing 400014, China; 10Department of Infectious Diseases, Children’s Hospital of Fudan University, Shanghai 200336, ChinaCorrespondence: Mei ZengDepartment of Infectious Diseases, Children’s Hospital of Fudan University, 399 Wanyuan Road, Shanghai 201102, ChinaEmail zengmeigao@aliyun.comJianmin ZhangCollege of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, ChinaTel +86 20 8528 0240Fax +86 20 8528 5282Email junfeng-v@163.comPurpose: Human infections caused by invasive non-typhoidal Salmonella (iNTS) are highly prevalent worldwide. However, data for such infections in China are scarce. This study reports the epidemiology of iNTS in China.Methods: INTS isolates were recovered from blood and other clinical specimens collected during 2007–2016 across five provinces (Shanghai, Xinjiang, Fujian, Guangxi, and Chongqing) in China. Antimicrobial susceptibility was performed using the agar dilution method and molecular epidemiology was performed using standard microbiological techniques.Results: A total of 178 iNTS isolates were recovered from approximately 9700 patient specimens during 2007–2016. The predominant serovars were Salmonella Enteritidis (57/178, 32%), Salmonella Choleraesuis (47/178, 26.4%), and Salmonella Typhimurium (24/178, 13.5%). Up to 50 isolates (28.1%) were from patients who were ≤1 year of age, while 28 (15.7%) were from patients who were ≥60 years. Among these isolates, high rates of resistance to nalidixic acid (114/178, 64%), sulfisoxazole (59%), ciprofloxacin (15.2%), and cefotaxime (8.4%) were found. Moreover, 53.4% (95/178) exhibited multidrug resistance, and 3.9% (7/178) showed co-resistance to third-generation cephalosporins and ciprofloxacin. Steadily increasing numbers of nalidixic acid, cefotaxime, and ciprofloxacin-resistant isolates, but decreasing numbers of multidrug resistance isolates were detected during the study period. Detection of quinolone genes in 114 nalidixic acid-resistant isolates showed that 58.3% (67/114) harbored plasmid-mediated quinolone resistance (PMQR) genes [aac(6´)-Ib-cr, qnrA, qnrB, oqxAB, qepA, qnrS, and qnrD] and 98.2% (112/114) exhibited mutations in quinolone resistance determining regions [gyrA, parC, and parE]. Furthermore, we detected beta-lactamases genes in the ceftriaxone-resistant isolates. The most common were blaTEM-1 (93.3%), followed by blaCTX-M-55 (40%), blaCMY-2 (33.3%), and blaOXA-1 (33.3%). Finally, a range of pulsed-field gel electrophoresis patterns were detected among the Salmonella Enteritidis and Salmonella Typhimurium isolates.Conclusion: High rates of multidrug resistance and steadily increasing cefotaxime and ciprofloxacin-resistant iNTS could pose a significant challenge for the effective treatment of salmonellosis in China.Keywords: invasive non-typhoidal Salmonella, fluoroquinolones, multidrug resistant, beta-lactamases, pulsed field gel electrophoresis, China

Abstract Background Multidrug-resistant (MDR) Acinetobacter baumannii infections are considered as emerging nosocomial infections particularly in patients hospitalized in intensive care units (ICUs). Therefore, reliable detection of MDR strains is crucial for management of treatment but also for epidemiological data collections. The purpose of this study was to compare antimicrobial resistance and the clonal distribution of MDR clinical and environmental A. baumannii isolates obtained from the ICUs of 10 different hospitals from five geographical regions of Turkey in the context of the demographic and clinical characteristics of the patients. Methods A multicenter-prospective study was conducted in 10 medical centers of Turkey over a 6 month period. A total of 164 clinical and 12 environmental MDR A. baumannii isolates were included in the study. Antimicrobial susceptibility testing was performed for amikacin (AN), ampicillin–sulbactam (SAM), ceftazidime (CAZ), ciprofloxacin (CIP), imipenem (IMP) and colistin (COL) by microdilution method and by antibiotic gradient test for tigecycline (TIG). Pulsed-field gel electrophoresis (PFGE) was performed to determine the clonal relationship between the isolates. The detection of the resistance genes, bla OXA-23, bla OXA-24, bla OXA-51, bla OXA-58, bla IMP, bla NDM, bla KPC, bla OXA-48 and bla PER-1 was carried out using the PCR method. Results The mortality rate of the 164 patients was 58.5%. The risk factors for mortality included diabetes mellitus, liv1er failure, the use of chemotherapy and previous use of quinolones. Antimicrobial resistance rates for AN, SAM, CAZ, CIP, IMP, COL and TIG were 91.8%, 99.4%, 99.4%, 100%, 99.4%, 1.2% and 1.7% respectively. Colistin showed the highest susceptibility rate. Four isolates did not grow on the culture and were excluded from the analyses. Of 172 isolates, 166 (96.5%) carried bla OXA-23, 5 (2.9%) bla OXA-58 and one isolate (0.6%) was positive for both genes. The frequency of bla PER-1 was found to be 2.9%. None of the isolates had bla IMP, bla KPC, bla NDM and bla OXA-48 genes. PFGE analysis showed 88 pulsotypes. Fifteen isolates were clonally unrelated. One hundred fifty-seven (91.2%) of the isolates were involved in 14 different clusters. Conclusions Colistin is still the most effective antibiotic for A. baumannii infections. The gene bla OXA-23 has become the most prevalent carbapenemase in Turkey. The distribution of invasive A. baumannii isolates from different regions of Turkey is not diverse so, infection control measures at medical centers should be revised to decrease the MDR A. baumannii infections across the country. The results of this study are expected to provide an important baseline to assess the future prophylactic and therapeutic options.

ABSTRACT Introduction: Bacterial tonsillitis is an upper respiratory tract infection that occurs primarily in children and adolescents. Staphylococcus aureus is one of the most frequent pathogens in the etiology of tonsillitis and its relevance is due to its antimicrobial resistance and persistence in the internal tissues of the tonsils. Tonsillectomy is indicated in cases of recurrent tonsillitis after several failures of antibiotic therapy. Material and methods: In this study we evaluated 123 surgically removed tonsils from patients who had history of recurrent tonsillitis. The tonsils were submitted to microbiological analysis for detection of S. aureus. The isolates were identified by PCR for femA gene. Antimicrobial susceptibility of the isolates was determined by disk diffusion tests. All isolates were submitted to PCR to detect mecA and Panton-Valentine leucocidin (PVL) genes. The genetic similarity among all isolates was determined by pulsed field gel electrophoresis. Results: Sixty-one S. aureus isolates were obtained from 50 patients (40.7%) with mean age of 11.7 years. The isolates showed high level resistance to penicillin (83.6%), 9.8% had inducible MLSb phenotype, and 18.0% were considered multidrug resistant (MDR). mecA gene was detected in two isolates and the gene coding for PVL was identified in one isolate. The genetic similarity analysis showed high diversity among the isolates. More than one genetically different isolate was identified from the same patient, and identical isolates were obtained from different patients. Conclusions: MDR isolates colonizing tonsils even without infection, demonstrate persistence of the bacterium and possibility of antimicrobial resistance dissemination and recurrence of infection. A specific clone in patients colonized by S. aureus was not demonstrated.

Understanding the plasticity of genomes has been greatly aided by assays for recombination, repair and mutagenesis. These assays have been developed in microbial systems that provide the advantages of genetic and molecular reporters that can readily be manipulated. Cellular assays comprise genetic, molecular, and cytological reporters. The assays are powerful tools but each comes with its particular advantages and limitations. Here the most commonly used assays are reviewed, discussed, and presented as the guidelines for future studies.

ABSTRACT Brazil is the largest exporter of chicken meat and poultry farming is one of the most important productive segments, despite major losses due to the bacterium Escherichia coli, which is also a zoonotic microorganism. The objetive of this study was to isolate E. coli and to evaluate its transmissibility potential from the field to chicken meat using the Pulsed Field Gel Electrophoresis (PFGE) technique. Environmental samples (poultry litter, soil and water) were collected from broiler farms located in the South of Brazil where the majority of the Brazilian poultry production occurs. In addition, chicken meat (gizzard, heart, drumette and tulip) samples were collected from local supermarkets. As results, 47.36% of the samples were positives for E. coli. Furthermore, 10 pairs of clones of E. coli were found always in the same substrate (two water-water pairs; three soil-soil pairs and five meat-meat pairs) using PFGE. These findings suggest that certain strains of E. coli may have habitat preferences, making the transfer from one substrate type to another more difficult to occur. Moreover, since no clones were found between environmental samples and chicken meat, it is possible to imply a low risk of E. coli transmissibility throughout the chicken meat production chain.

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Stenotrophomonas maltophilia isolates are responsible for various hospitalacquired infections and are particularly increasing in the immunocompromised patients. The aim of this study was to determine the clonal relatedness between S. maltophilia isolates originating from the clinic and environment. A total of 150 S. maltophilia isolates from patients and 1108 environmental samples obtained in three hospitals from Tehran. Following molecular identification targeting 23S rRNA gene, the clonal relatedness of the environmental and clinical isolates was determined using pulsed field gel electrophoresis (PFGE). Of the 150 clinical and 18 environmental isolates identified using phenotypic tests, the speciation of 120 and 15 was confirmed by targeting the 23S rRNA gene. The 24 common pulsotypes (PTs) and 32 single PTs were identified by PFGE. Only a small cluster was shared among the clinic and environment within a hospital; therefore, the intra-hospital dissemination of certain isolates of S. maltophilia among the clinic and environment was demonstrated. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chlorhexidine and mupirocin are used in health care facilities to eradicate methicillin-resistant Staphylococcus aureus (MRSA) carriage. The objective of this study was to assess the frequency of chlorhexidine and mupirocin resistance in isolates from nares carriers in multiple nursing homes and to examine characteristics associated with resistance. Nasal swab samples were collected from approximately 100 new admissions and 100 current residents in 26 nursing homes in Orange County, CA, from October 2008 to May 2011. MRSA isolates were tested for susceptibility by using broth microdilution, disk diffusion, and Etest; for genetic relatedness using pulsed-field gel electrophoresis; and for qac gene carriage by PCR. Characteristics of the nursing homes and their residents were collected from the Medicare Minimum Data Set and Long-Term Care Focus. A total of 829 MRSA isolates were obtained from swabbing 3,806 residents in 26 nursing homes. All isolates had a chlorhexidine MIC of ≤4 μg/ml. Five (0.6%) isolates harbored the qacA and/or qacB gene loci. Mupirocin resistance was identified in 101 (12%) isolates, with 78 (9%) isolates exhibiting high-level mupirocin resistance (HLMR). HLMR rates per facility ranged from 0 to 31%. None of the isolates with HLMR displayed qacA or qacB, while two isolates carried qacA and exhibited low-level mupirocin resistance. Detection of HLMR was associated with having a multidrug-resistant MRSA isolate (odds ratio [OR], 2.69; P = 0.004), a history of MRSA (OR, 2.34; P < 0.001), and dependency in activities of daily living (OR, 1.25; P = 0.004). In some facilities, HLMR was found in nearly one-third of MRSA isolates. These findings may have implications for the increasingly widespread practice of MRSA decolonization using intranasal mupirocin.

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Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)