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Sample records for antimicrobial resistance genes

  1. Identification of acquired antimicrobial resistance genes

    DEFF Research Database (Denmark)

    Zankari, Ea; Hasman, Henrik; Cosentino, Salvatore;

    2012-01-01

    antimicrobial resistance genes in whole-genome data. As input, the method can use both pre-assembled, complete or partial genomes, and short sequence reads from four different sequencing platforms. The method was evaluated on 1862 GenBank files containing 1411 different resistance genes, as well as on 23 de......-novo-sequenced isolates.ResultsWhen testing the 1862 GenBank files, the method identified the resistance genes with an ID = 100% (100% identity) to the genes in ResFinder. Agreement between in silico predictions and phenotypic testing was found when the method was further tested on 23 isolates of five different bacterial...

  2. Antimicrobial-Resistant Bacterial Populations and Antimicrobial Resistance Genes Obtained from Environments Impacted by Livestock and Municipal Waste.

    Directory of Open Access Journals (Sweden)

    Getahun E Agga

    Full Text Available This study compared the populations of antimicrobial-resistant bacteria and the repertoire of antimicrobial resistance genes in four environments: effluent of three municipal wastewater treatment facilities, three cattle feedlot runoff catchment ponds, three swine waste lagoons, and two "low impact" environments (an urban lake and a relict prairie. Multiple liquid and solid samples were collected from each environment. The prevalences and concentrations of antimicrobial-resistant (AMR Gram-negative (Escherichia coli and Salmonella enterica and Gram-positive (enterococci bacteria were determined from individual samples (n = 174. The prevalences of 84 antimicrobial resistance genes in metagenomic DNA isolated from samples pooled (n = 44 by collection date, location, and sample type were determined. The prevalences and concentrations of AMR E. coli and Salmonella were similar among the livestock and municipal sample sources. The levels of erythromycin-resistant enterococci were significantly higher in liquid samples from cattle catchment ponds and swine waste lagoons than in liquid samples from municipal wastewater treatment facilities, but solid samples from these environments did not differ significantly. Similarly, trimethoprim/sulfamethoxazole-resistant E. coli concentrations were significantly higher in swine liquid than in municipal liquid samples, but there was no difference in solid samples. Multivariate analysis of the distribution of antimicrobial resistance genes using principal coordinate analysis showed distinct clustering of samples with livestock (cattle and swine, low impact environment and municipal samples forming three separate clusters. The numbers of class A beta-lactamase, class C beta-lactamase, and fluoroquinolone resistance genes detected were significantly higher (P < 0.05 in municipal samples than in cattle runoff or swine lagoon samples. In conclusion, we report that AMR is a very widespread phenomenon and that similar

  3. Occurrence of antimicrobials and antimicrobial resistance genes in beef cattle storage ponds and swine treatment lagoons

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yuping; Zhang, Chiqian [Department of Civil Engineering, University of Nebraska-Lincoln, Lincoln, NE (United States); Parker, David B. [USDA Meat Animal Research Center, Clay Center, NE (United States); Snow, Daniel D. [Water Sciences Laboratory, University of Nebraska-Lincoln, Lincoln, NE (United States); Zhou, Zhi [Department of Civil and Environmental Engineering, National University of Singapore (Singapore); Li, Xu, E-mail: xuli@unl.edu [Department of Civil Engineering, University of Nebraska-Lincoln, Lincoln, NE (United States)

    2013-10-01

    Livestock manure treatment and storage structures are potential environmental sources of antimicrobials and antimicrobial resistance genes (ARGs). In this study, the occurrence of antimicrobials and ARGs was investigated in the water and the sludge compartments of beef cattle storage ponds and swine lagoons. Analysis was focused on two families of antimicrobials (sulfonamide and tetracycline) and the corresponding ARGs (sul1, sul2, tetO, tetQ and tetX). Results showed that the pseudo-partitioning coefficients of tetracyclines were higher than those of sulfonamides, suggesting different distributions of these two classes of antimicrobials between water and sludge. The ARGs tested were detected in nearly all ponds and lagoons, with the highest relative abundance in sul2 at 6.3 × 10{sup −1} copies per 16S rRNA gene. A positive correlation was observed between total sul genes and total sulfonamides in water while the correlation was negative in sludge. No significant correlation was found between total tet genes and total tetracyclines in either water or sludge, but significant correlations were observed for certain individual tet genes. Ammonia concentrations strongly correlated with all ARGs except tetX. This study provided quantitative information on the occurrence of antimicrobials and ARGs in the liquid and solid compartments of typical manure treatment and storage structures. - Highlights: • Partitioning of antimicrobials between water and sludge is compound specific. • Antimicrobial resistance genes occurred in both water and sludge. • The ARG abundance varied more substantially in swine lagoons than in cattle ponds. • Correlations between ARGs and antimicrobials are system dependent.

  4. Resistance of Antimicrobial Peptide Gene Transgenic Rice to Bacterial Blight

    Institute of Scientific and Technical Information of China (English)

    WANG Wei; WU Chao; LIU Mei; LIU Xu-ri; Hu Guo-cheng; SI Hua-min; SUN Zong-xiu; LIU Wen-zhen; Fu Ya-ping

    2011-01-01

    Antimierobial peptide is a polypeptide with antimicrobial activity.Antimicrobial peptide genes Np3 and Np5 from Chinese shrimp (Fenneropenaeus Chinensis) were integrated into Oryza sativa L.subsp.japonica cv.Aichi ashahi by Agrobacterium mediated transformation system.PCR analysis showed that the positive ratios of Np3 and Np5 were 36% and 45% in T0 generation,respectively.RT-PCR analysis showed that the antimicrobial peptide genes were expressed in T1 generation,and there was no obvious difference in agronomic traits between transgenic plants and non-transgenic plants.Four Np3 and Np5 transgenic lines in T1 generation were inoculated with ×anthomonas oryzae pv.oryzae strain CR4,and all the four transgenic lines had significantly enhanced resistance to bacterial blight caused by the strain CR4.The Np5 transgenic lines also showed higher resistance to bacterial blight caused by strains JS97-2,Zhe 173 and OS-225.It is suggested that transgenic lines with Np5 gene might possess broad spectrum resistance to rice bacterial blight.

  5. Occurrence of antimicrobials and antimicrobial resistance genes in beef cattle storage ponds and swine treatment lagoons.

    Science.gov (United States)

    Zhang, Yuping; Zhang, Chiqian; Parker, David B; Snow, Daniel D; Zhou, Zhi; Li, Xu

    2013-10-01

    Livestock manure treatment and storage structures are potential environmental sources of antimicrobials and antimicrobial resistance genes (ARGs). In this study, the occurrence of antimicrobials and ARGs was investigated in the water and the sludge compartments of beef cattle storage ponds and swine lagoons. Analysis was focused on two families of antimicrobials (sulfonamide and tetracycline) and the corresponding ARGs (sul1, sul2, tetO, tetQ and tetX). Results showed that the pseudo-partitioning coefficients of tetracyclines were higher than those of sulfonamides, suggesting different distributions of these two classes of antimicrobials between water and sludge. The ARGs tested were detected in nearly all ponds and lagoons, with the highest relative abundance in sul2 at 6.3×10(-1) copies per 16S rRNA gene. A positive correlation was observed between total sul genes and total sulfonamides in water while the correlation was negative in sludge. No significant correlation was found between total tet genes and total tetracyclines in either water or sludge, but significant correlations were observed for certain individual tet genes. Ammonia concentrations strongly correlated with all ARGs except tetX. This study provided quantitative information on the occurrence of antimicrobials and ARGs in the liquid and solid compartments of typical manure treatment and storage structures. PMID:23838056

  6. Antimicrobial-Resistant Bacterial Populations and Antimicrobial Resistance Genes Obtained from Environments Impacted by Livestock and Municipal Waste.

    Science.gov (United States)

    Agga, Getahun E; Arthur, Terrance M; Durso, Lisa M; Harhay, Dayna M; Schmidt, John W

    2015-01-01

    This study compared the populations of antimicrobial-resistant bacteria and the repertoire of antimicrobial resistance genes in four environments: effluent of three municipal wastewater treatment facilities, three cattle feedlot runoff catchment ponds, three swine waste lagoons, and two "low impact" environments (an urban lake and a relict prairie). Multiple liquid and solid samples were collected from each environment. The prevalences and concentrations of antimicrobial-resistant (AMR) Gram-negative (Escherichia coli and Salmonella enterica) and Gram-positive (enterococci) bacteria were determined from individual samples (n = 174). The prevalences of 84 antimicrobial resistance genes in metagenomic DNA isolated from samples pooled (n = 44) by collection date, location, and sample type were determined. The prevalences and concentrations of AMR E. coli and Salmonella were similar among the livestock and municipal sample sources. The levels of erythromycin-resistant enterococci were significantly higher in liquid samples from cattle catchment ponds and swine waste lagoons than in liquid samples from municipal wastewater treatment facilities, but solid samples from these environments did not differ significantly. Similarly, trimethoprim/sulfamethoxazole-resistant E. coli concentrations were significantly higher in swine liquid than in municipal liquid samples, but there was no difference in solid samples. Multivariate analysis of the distribution of antimicrobial resistance genes using principal coordinate analysis showed distinct clustering of samples with livestock (cattle and swine), low impact environment and municipal samples forming three separate clusters. The numbers of class A beta-lactamase, class C beta-lactamase, and fluoroquinolone resistance genes detected were significantly higher (P waste streams, but a higher diversity of antimicrobial resistance genes are present in treated human waste discharged from municipal wastewater treatment plants than in

  7. Antimicrobial resistance and antimicrobial resistance genes in marine bacteria from salmon aquaculture and non-aquaculture sites.

    Science.gov (United States)

    Shah, Syed Q A; Cabello, Felipe C; L'abée-Lund, Trine M; Tomova, Alexandra; Godfrey, Henry P; Buschmann, Alejandro H; Sørum, Henning

    2014-05-01

    Antimicrobial resistance (AR) detected by disc diffusion and antimicrobial resistance genes detected by DNA hybridization and polymerase chain reaction with amplicon sequencing were studied in 124 marine bacterial isolates from a Chilean salmon aquaculture site and 76 from a site without aquaculture 8 km distant. Resistance to one or more antimicrobials was present in 81% of the isolates regardless of site. Resistance to tetracycline was most commonly encoded by tetA and tetG; to trimethoprim, by dfrA1, dfrA5 and dfrA12; to sulfamethizole, by sul1 and sul2; to amoxicillin, by blaTEM ; and to streptomycin, by strA-strB. Integron integrase intl1 was detected in 14 sul1-positive isolates, associated with aad9 gene cassettes in two from the aquaculture site. intl2 Integrase was only detected in three dfrA1-positive isolates from the aquaculture site and was not associated with gene cassettes in any. Of nine isolates tested for conjugation, two from the aquaculture site transferred AR determinants to Escherichia coli. High levels of AR in marine sediments from aquaculture and non-aquaculture sites suggest that dispersion of the large amounts of antimicrobials used in Chilean salmon aquaculture has created selective pressure in areas of the marine environment far removed from the initial site of use of these agents.

  8. Antimicrobial resistance and prevalence of resistance genes in intestinal Bacteroidales strains

    Directory of Open Access Journals (Sweden)

    Viviane Nakano

    2011-01-01

    Full Text Available OBJECTIVE: This study examined the antimicrobial resistance profile and the prevalence of resistance genes in Bacteroides spp. and Parabacteroides distasonis strains isolated from children's intestinal microbiota. METHODS: The susceptibility of these bacteria to 10 antimicrobials was determined using an agar dilution method. β-lactamase activity was assessed by hydrolysis of the chromogenic cephalosporin of 114 Bacteriodales strains isolated from the fecal samples of 39 children, and the presence of resistance genes was tested using a PCR assay. RESULTS: All strains were susceptible to imipenem and metronidazole. The following resistance rates were observed: amoxicillin (93%, amoxicillin/clavulanic acid (47.3%, ampicillin (96.4%, cephalexin (99%, cefoxitin (23%, penicillin (99%, clindamycin (34.2% and tetracycline (53.5%. P-lactamase production was verified in 92% of the evaluated strains. The presence of the cfiA, cepA, ermF, tetQ and nim genes was observed in 62.3%, 76.3%, 27%, 79.8% and 7.8% of the strains, respectively. CONCLUSIONS: Our results indicate an increase in the resistance to several antibiotics in intestinal Bacteroides spp. and Parabacteroides distasonis and demonstrate that these microorganisms harbor antimicrobial resistance genes that may be transferred to other susceptible intestinal strains.

  9. Association between antimicrobial resistance and virulence genes in Escherichia coli obtained from blood and faeces

    DEFF Research Database (Denmark)

    Bagger-Skjøt, Line; Sandvang, Dorthe; Frimodt-Møller, Niels;

    2007-01-01

    Escherichia coli isolates obtained from faeces (n = 85) and blood (n = 123) were susceptibility tested against 17 antimicrobial agents and the presence of 9 virulence genes was determined by PCR. Positive associations between several antimicrobial resistances and 2 VF genes (iutA and traT) were...

  10. Bacteriophages Isolated from Chicken Meat and the Horizontal Transfer of Antimicrobial Resistance Genes

    Science.gov (United States)

    Shousha, Amira; Awaiwanont, Nattakarn; Sofka, Dmitrij; Smulders, Frans J. M.; Paulsen, Peter; Szostak, Michael P.; Humphrey, Tom

    2015-01-01

    Antimicrobial resistance in microbes poses a global and increasing threat to public health. The horizontal transfer of antimicrobial resistance genes was thought to be due largely to conjugative plasmids or transposons, with only a minor part being played by transduction through bacteriophages. However, whole-genome sequencing has recently shown that the latter mechanism could be highly important in the exchange of antimicrobial resistance genes between microorganisms and environments. The transfer of antimicrobial resistance genes by phages could underlie the origin of resistant bacteria found in food. We show that chicken meat carries a number of phages capable of transferring antimicrobial resistance. Of 243 phages randomly isolated from chicken meat, about a quarter (24.7%) were able to transduce resistance to one or more of the five antimicrobials tested into Escherichia coli ATCC 13706 (DSM 12242). Resistance to kanamycin was transduced the most often, followed by that to chloramphenicol, with four phages transducing tetracycline resistance and three transducing ampicillin resistance. Phages able to transduce antimicrobial resistance were isolated from 44% of the samples of chicken meat that we tested. The statistically significant (P = 0.01) relationship between the presence of phages transducing kanamycin resistance and E. coli isolates resistant to this antibiotic suggests that transduction may be an important mechanism for transferring kanamycin resistance to E. coli. It appears that the transduction of resistance to certain antimicrobials, e.g., kanamycin, not only is widely distributed in E. coli isolates found on meat but also could represent a major mechanism for resistance transfer. The result is of high importance for animal and human health. PMID:25934615

  11. Bacteriophages Isolated from Chicken Meat and the Horizontal Transfer of Antimicrobial Resistance Genes.

    Science.gov (United States)

    Shousha, Amira; Awaiwanont, Nattakarn; Sofka, Dmitrij; Smulders, Frans J M; Paulsen, Peter; Szostak, Michael P; Humphrey, Tom; Hilbert, Friederike

    2015-07-01

    Antimicrobial resistance in microbes poses a global and increasing threat to public health. The horizontal transfer of antimicrobial resistance genes was thought to be due largely to conjugative plasmids or transposons, with only a minor part being played by transduction through bacteriophages. However, whole-genome sequencing has recently shown that the latter mechanism could be highly important in the exchange of antimicrobial resistance genes between microorganisms and environments. The transfer of antimicrobial resistance genes by phages could underlie the origin of resistant bacteria found in food. We show that chicken meat carries a number of phages capable of transferring antimicrobial resistance. Of 243 phages randomly isolated from chicken meat, about a quarter (24.7%) were able to transduce resistance to one or more of the five antimicrobials tested into Escherichia coli ATCC 13706 (DSM 12242). Resistance to kanamycin was transduced the most often, followed by that to chloramphenicol, with four phages transducing tetracycline resistance and three transducing ampicillin resistance. Phages able to transduce antimicrobial resistance were isolated from 44% of the samples of chicken meat that we tested. The statistically significant (P = 0.01) relationship between the presence of phages transducing kanamycin resistance and E. coli isolates resistant to this antibiotic suggests that transduction may be an important mechanism for transferring kanamycin resistance to E. coli. It appears that the transduction of resistance to certain antimicrobials, e.g., kanamycin, not only is widely distributed in E. coli isolates found on meat but also could represent a major mechanism for resistance transfer. The result is of high importance for animal and human health.

  12. Antimicrobial Resistance and Resistance Genes in Aerobic Bacteria Isolated from Pork at Slaughter

    DEFF Research Database (Denmark)

    Li, Lili; Olsen, Rikke Heidemann; Ye, Lei;

    2016-01-01

    The aim of this study was to investigate the phenotypic and genotypic antimicrobial resistance, integrons, and transferability of resistance markers in 243 aerobic bacteria recovered from pork at slaughter in the People's Republic of China. The organisms belonged to 22 genera of gram-negative bac...... of aerobic bacteria from pork as reservoirs for antimicrobial resistance genes and mobile genetic elements that can readily be transferred intra- and interspecies.......The aim of this study was to investigate the phenotypic and genotypic antimicrobial resistance, integrons, and transferability of resistance markers in 243 aerobic bacteria recovered from pork at slaughter in the People's Republic of China. The organisms belonged to 22 genera of gram......-negative bacteria (92.2%) and gram-positive bacteria (7.8%). High levels of resistance were detected to tetracycline, trimethoprim-sulfamethoxazole, and ampicillin (36.2 to 54.3%), and lower levels were detected to nitrofurantoin, cefotaxime, gentamicin, ciprofloxacin, and chloramphenicol (7.8 to 29.2%). Across...

  13. Antimicrobial resistance

    DEFF Research Database (Denmark)

    Llor, Carl; Bjerrum, Lars

    2014-01-01

    Antimicrobial resistance is a global public health challenge, which has accelerated by the overuse of antibiotics worldwide. Increased antimicrobial resistance is the cause of severe infections, complications, longer hospital stays and increased mortality. Overprescribing of antibiotics...... is associated with an increased risk of adverse effects, more frequent re-attendance and increased medicalization of self-limiting conditions. Antibiotic overprescribing is a particular problem in primary care, where viruses cause most infections. About 90% of all antibiotic prescriptions are issued by general...... practitioners, and respiratory tract infections are the leading reason for prescribing. Multifaceted interventions to reduce overuse of antibiotics have been found to be effective and better than single initiatives. Interventions should encompass the enforcement of the policy of prohibiting the over...

  14. Antimicrobial Chemicals Are Associated with Elevated Antibiotic Resistance Genes in the Indoor Dust Microbiome.

    Science.gov (United States)

    Hartmann, Erica M; Hickey, Roxana; Hsu, Tiffany; Betancourt Román, Clarisse M; Chen, Jing; Schwager, Randall; Kline, Jeff; Brown, G Z; Halden, Rolf U; Huttenhower, Curtis; Green, Jessica L

    2016-09-20

    Antibiotic resistance is increasingly widespread, largely due to human influence. Here, we explore the relationship between antibiotic resistance genes and the antimicrobial chemicals triclosan, triclocarban, and methyl-, ethyl-, propyl-, and butylparaben in the dust microbiome. Dust samples from a mixed-use athletic and educational facility were subjected to microbial and chemical analyses using a combination of 16S rRNA amplicon sequencing, shotgun metagenome sequencing, and liquid chromatography tandem mass spectrometry. The dust resistome was characterized by identifying antibiotic resistance genes annotated in the Comprehensive Antibiotic Resistance Database (CARD) from the metagenomes of each sample using the Short, Better Representative Extract Data set (ShortBRED). The three most highly abundant antibiotic resistance genes were tet(W), blaSRT-1, and erm(B). The complete dust resistome was then compared against the measured concentrations of antimicrobial chemicals, which for triclosan ranged from 0.5 to 1970 ng/g dust. We observed six significant positive associations between the concentration of an antimicrobial chemical and the relative abundance of an antibiotic resistance gene, including one between the ubiquitous antimicrobial triclosan and erm(X), a 23S rRNA methyltransferase implicated in resistance to several antibiotics. This study is the first to look for an association between antibiotic resistance genes and antimicrobial chemicals in dust. PMID:27599587

  15. Incidence of antimicrobial-resistance genes and integrons in antibiotic-resistant bacteria isolated from eels and aquaculture ponds.

    Science.gov (United States)

    Lin, Mao; Wu, Xiaomei; Yan, Qingpi; Ma, Ying; Huang, Lixing; Qin, Yingxue; Xu, Xiaojin

    2016-07-01

    The overuse of antimicrobials in aquaculture has promoted the selection of antimicrobial-resistant bacteria. Here we investigated the abundance of antimicrobial-resistance genes and integrons in 108 strains of antibiotic-resistant bacteria isolated from eels and aquaculture ponds in China. Conventional PCR was implemented to examine common antibiotic-resistance genes, integrons, and their gene cassette arrays. The results showed that the antibiotic-resistance genes blaTEM, tetC, sulI, aadA, floR, and qnrB were detected at high percentages, as were a number of other resistance genes. Class I integrons were present in 79.63% of the strains, and 10 out of 108 isolates carried class II integrons. Class III integrons were not detected. Three strains carried both class I and class II integrons, and 73.26% of the class I integron-positive isolates contained the qacEΔ1/sul1 gene. Fourteen types of integron cassette arrays were found among class I integron-positive isolates. A new array, dfrB4-catB3-blaOXA-10-aadA1, was discovered in this study. The gene cassette array dfrA12-orfF-aadA2 was the most widely distributed. In summary, 23 different gene cassettes encoding resistance to 8 classes of antibiotics were identified in the class I integrons, and the main cassettes contained genes encoding resistance to aminoglycosides (aad) and trimethoprim (dfr). All class II integron-positive strains had only a single gene cassette array, viz. dfrA1-catB2-sat2-aadA1. High levels of antimicrobial-resistance genes and integrons in eels and auqauculture ponds suggest that the overuse of antimicrobials should be strictly controlled and that the levels of bacterial antimicrobial-resistance genes in aquaculture should be monitored. PMID:27409235

  16. Animation of Antimicrobial Resistance

    Science.gov (United States)

    ... Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it ... Veterinary Medicine is cited as the corporate author. Animation Animation of Antimicrobial Resistance (WMV - 19.2MB) 9: ...

  17. Animation of Antimicrobial Resistance

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    Full Text Available ... 08 Animation of Antimicrobial Resistance (text version) Arabic Translation - Animation of Antimicrobial Resistance (WMV - 19.2MB) Chinese Translation - Animation of Antimicrobial Resistance (WMV - 19.2MB) French ...

  18. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... More in Antimicrobial Resistance National Antimicrobial Resistance Monitoring System ... Note: If you need help accessing information in different file formats, see Instructions for Downloading ...

  19. Diversity of antimicrobial resistance and virulence genes in methicillin-resistant non-Staphylococcus aureus staphylococci from veal calves.

    Science.gov (United States)

    Argudín, M Angeles; Vanderhaeghen, Wannes; Butaye, Patrick

    2015-04-01

    In this study we determined whether methicillin-resistant non-Staphylococcus aureus (MRNAS) from veal calves may be a potential reservoir of antimicrobial-resistance and virulence genes. Fifty-eight MRNAS were studied by means of DNA-microarray and PCR for detection of antimicrobial resistance and virulence genes. The isolates carried a variety of antimicrobial-resistance genes [aacA-aphD, aadD, aph3, aadE, sat, spc, ampA, erm(A), erm(B), erm(C), erm(F), erm(T), lnu(A), msr(A)-msr(B), vga(A), mph(C), tet(K), tet(M), tet(L), cat, fexA, dfrA, dfrD, dfrG, dfrK, cfr, fusB, fosB, qacA, qacC, merA-merB]. Some isolates carried resistance genes without showing the corresponding resistance phenotype. Most MRNAS carried typical S. aureus virulence factors like proteases (sspP) and enterotoxins (seg) genes. Most Staphylococcus epidermidis isolates carried the arginine catabolic element, and nearly 40% of the Staphylococcus sciuri isolates carried leukocidins, and/or fibronectin-binding protein genes. MRNAS were highly multi-resistant and represent an important reservoir of antimicrobial resistance and virulence genes. PMID:25637268

  20. Antimicrobial Drugs in Fighting against Antimicrobial Resistance.

    Science.gov (United States)

    Cheng, Guyue; Dai, Menghong; Ahmed, Saeed; Hao, Haihong; Wang, Xu; Yuan, Zonghui

    2016-01-01

    The outbreak of antimicrobial resistance, together with the lack of newly developed antimicrobial drugs, represents an alarming signal for both human and animal healthcare worldwide. Selection of rational dosage regimens for traditional antimicrobial drugs based on pharmacokinetic/pharmacodynamic principles as well as development of novel antimicrobials targeting new bacterial targets or resistance mechanisms are key approaches in tackling AMR. In addition to the cellular level resistance (i.e., mutation and horizontal gene transfer of resistance determinants), the community level resistance (i.e., bilofilms and persisters) is also an issue causing antimicrobial therapy difficulties. Therefore, anti-resistance and antibiofilm strategies have currently become research hotspot to combat antimicrobial resistance. Although metallic nanoparticles can both kill bacteria and inhibit biofilm formation, the toxicity is still a big challenge for their clinical applications. In conclusion, rational use of the existing antimicrobials and combinational use of new strategies fighting against antimicrobial resistance are powerful warranties to preserve potent antimicrobial drugs for both humans and animals. PMID:27092125

  1. Antimicrobial Drugs in Fighting against Antimicrobial Resistance

    Directory of Open Access Journals (Sweden)

    Guyue eCheng

    2016-04-01

    Full Text Available The outbreak of antimicrobial resistance, together with the lack of newly developed antimicrobial drugs, represents an alarming signal for both human and animal healthcare worldwide. Selection of rational dosage regimens for traditional antimicrobial drugs based on pharmacokinetic/pharmacodynamic principles as well as development of novel antimicrobials targeting new bacterial targets or resistance mechanisms are key approaches in tackling AMR. In addition to the cellular level resistance (i.e., mutation and horizontal gene transfer of resistance determinants, the community level resistance (i.e., bilofilms and persisters is also an issue causing antimicrobial therapy difficulties. Therefore, anti-resistance and antibiofilm strategies have currently become research hotspot to combat antimicrobial resistance. Although metallic nanoparticles can both kill bacteria and inhibit biofilm formation, the toxicity is still a big challenge for their clinical applications. In conclusion, rational use of the existing antimicrobials and combinational use of new strategies fighting against antimicrobial resistance are powerful warranties to preserve potent antimicrobial drugs for both humans and animals.

  2. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... how antimicrobial resistance both emerges and proliferates among bacteria. Over time, the use of antimicrobial drugs will result in the development of resistant strains of bacteria, complicating clinician's efforts to select the appropriate antimicrobial ...

  3. Diversity of Plasmids and Antimicrobial Resistance Genes in Multidrug-Resistant Escherichia coli Isolated from Healthy Companion Animals.

    Science.gov (United States)

    Jackson, C R; Davis, J A; Frye, J G; Barrett, J B; Hiott, L M

    2015-09-01

    The presence and transfer of antimicrobial resistance genes from commensal bacteria in companion animals to more pathogenic bacteria may contribute to dissemination of antimicrobial resistance. The purpose of this study was to determine antimicrobial resistance gene content and the presence of genetic elements in antimicrobial resistant Escherichia coli from healthy companion animals. In our previous study, from May to August, 2007, healthy companion animals (155 dogs and 121 cats) from three veterinary clinics in the Athens, GA, USA area were sampled and multidrug-resistant E. coli (n = 36; MDR, resistance to ≥ 2 antimicrobial classes) were obtained. Of the 25 different plasmid replicon types tested by PCR, at least one plasmid replicon type was detected in 94% (34/36) of the MDR E. coli; four isolates contained as many as five different plasmid replicons. Nine replicon types (FIA, FIB, FII, I2, A/C, U, P, I1 and HI2) were identified with FIB, FII, I2 as the most common pattern. The presence of class I integrons (intI) was detected in 61% (22/36) of the isolates with eight isolates containing aminoglycoside- and/or trimethoprim-resistance genes in the variable cassette region of intI. Microarray analysis of a subset of the MDR E. coli (n = 9) identified the presence of genes conferring resistance to aminoglycosides (aac, aad, aph and strA/B), β-lactams (ampC, cmy, tem and vim), chloramphenicol (cat), sulfonamides (sulI and sulII), tetracycline [tet(A), tet(B), tet(C), tet(D) and regulator, tetR] and trimethoprim (dfrA). Antimicrobial resistance to eight antimicrobials (ampicillin, cefoxitin, ceftiofur, amoxicillin/clavulanic acid, streptomycin, gentamicin, sulfisoxazole and trimethoprim-sulfamethoxazole) and five plasmid replicons (FIA, FIB, FII, I1 and I2) were transferred via conjugation. The presence of antimicrobial resistance genes, intI and transferable plasmid replicons indicate that E. coli from companion animals may play an important role in the

  4. Development of a DNA microarray to detect antimicrobial resistance genes identified in the national center for biotechnology information database

    Science.gov (United States)

    High density genotyping techniques are needed for investigating antimicrobial resistance especially in the case of multi-drug resistant (MDR) isolates. To achieve this all antimicrobial resistance genes in the NCBI Genbank database were identified by key word searches of sequence annotations and the...

  5. Comparative metagenomics reveals a diverse range of antimicrobial resistance genes in effluents entering a river catchment.

    Science.gov (United States)

    Rowe, Will; Verner-Jeffreys, David W; Baker-Austin, Craig; Ryan, Jim J; Maskell, Duncan J; Pearce, Gareth P

    2016-01-01

    The aquatic environment has been implicated as a reservoir for antimicrobial resistance genes (ARGs). In order to identify sources that are contributing to these gene reservoirs, it is crucial to assess effluents that are entering the aquatic environment. Here we describe a metagenomic assessment for two types of effluent entering a river catchment. We investigated the diversity and abundance of resistance genes, mobile genetic elements (MGEs) and pathogenic bacteria. Findings were normalised to a background sample of river source water. Our results show that effluent contributed an array of genes to the river catchment, the most abundant being tetracycline resistance genes tetC and tetW from farm effluents and the sulfonamide resistance gene sul2 from wastewater treatment plant (WWTP) effluents. In nine separate samples taken across 3 years, we found 53 different genes conferring resistance to seven classes of antimicrobial. Compared to the background sample taken up river from effluent entry, the average abundance of genes was three times greater in the farm effluent and two times greater in the WWTP effluent. We conclude that effluents disperse ARGs, MGEs and pathogenic bacteria within a river catchment, thereby contributing to environmental reservoirs of ARGs.

  6. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... More in Antimicrobial Resistance National Antimicrobial Resistance Monitoring System About NARMS Bacteria (NARMS) NARMS at Work Reports ... Emergency Preparedness International Programs News & Events Training & Continuing Education Inspections & Compliance Federal, State & Local Officials Consumers Health ...

  7. SSTAR, a Stand-Alone Easy-To-Use Antimicrobial Resistance Gene Predictor.

    Science.gov (United States)

    de Man, Tom J B; Limbago, Brandi M

    2016-01-01

    We present the easy-to-use Sequence Search Tool for Antimicrobial Resistance, SSTAR. It combines a locally executed BLASTN search against a customizable database with an intuitive graphical user interface for identifying antimicrobial resistance (AR) genes from genomic data. Although the database is initially populated from a public repository of acquired resistance determinants (i.e., ARG-ANNOT), it can be customized for particular pathogen groups and resistance mechanisms. For instance, outer membrane porin sequences associated with carbapenem resistance phenotypes can be added, and known intrinsic mechanisms can be included. Unique about this tool is the ability to easily detect putative new alleles and truncated versions of existing AR genes. Variants and potential new alleles are brought to the attention of the user for further investigation. For instance, SSTAR is able to identify modified or truncated versions of porins, which may be of great importance in carbapenemase-negative carbapenem-resistant Enterobacteriaceae. SSTAR is written in Java and is therefore platform independent and compatible with both Windows and Unix operating systems. SSTAR and its manual, which includes a simple installation guide, are freely available from https://github.com/tomdeman-bio/Sequence-Search-Tool-for-Antimicrobial-Resistance-SSTAR-. IMPORTANCE Whole-genome sequencing (WGS) is quickly becoming a routine method for identifying genes associated with antimicrobial resistance (AR). However, for many microbiologists, the use and analysis of WGS data present a substantial challenge. We developed SSTAR, software with a graphical user interface that enables the identification of known AR genes from WGS and has the unique capacity to easily detect new variants of known AR genes, including truncated protein variants. Current software solutions do not notify the user when genes are truncated and, therefore, likely nonfunctional, which makes phenotype predictions less accurate. SSTAR

  8. Metagenomic Evidence of the Prevalence and Distribution Patterns of Antimicrobial Resistance Genes in Dairy Agroecosystems.

    Science.gov (United States)

    Pitta, Dipti W; Dou, Zhengxia; Kumar, Sanjay; Indugu, Nagaraju; Toth, John Daniel; Vecchiarelli, Bonnie; Bhukya, Bhima

    2016-06-01

    Antimicrobial resistance (AR) is a global problem with serious implications for public health. AR genes are frequently detected on animal farms, but little is known about their origin and distribution patterns. We hypothesized that AR genes can transfer from animal feces to the environment through manure, and to this end, we characterized and compared the resistomes (collections of AR genes) of animal feces, manure, and soil samples collected from five dairy farms using a metagenomics approach. Resistomes constituted only up to 1% of the total gene content, but were variable by sector and also farm. Broadly, the identified AR genes were associated with 18 antibiotic resistances classes across all samples; however, the most abundant genes were classified under multidrug transporters (44.75%), followed by resistance to vancomycin (12.48%), tetracycline (10.52%), bacitracin (10.43%), beta-lactam resistance (7.12%), and MLS efflux pump (6.86%) antimicrobials. The AR gene profiles were variable between farms. Farm 09 was categorized as a high risk farm, as a greater proportion of AR genes were common to at least three sectors, suggesting possible horizontal transfer of AR genes. Taxonomic characterization of AR genes revealed that a majority of AR genes were associated with the phylum Proteobacteria. Nonetheless, there were several members of Bacteroidetes, particularly Bacteroides genus and several lineages from Firmicutes that carried similar AR genes in different sectors, suggesting a strong potential for horizontal transfer of AR genes between unrelated bacterial hosts in different sectors of the farms. Further studies are required to affirm the horizontal gene transfer mechanisms between microbiomes of different sectors in animal agroecosystems. PMID:27046731

  9. Antimicrobial Resistance

    Science.gov (United States)

    ... others. For example, the emergence of Plasmodium falciparum multidrug resistance, including resistance to ACTs in the Greater Mekong subregion is an urgent public health concern that is threatening global efforts to reduce the burden of malaria. Although MDR-TB is a growing concern, it is still ...

  10. Antimicrobial Susceptibility of Bordetella bronchiseptica Isolates from Swine and Companion Animals and Detection of Resistance Genes.

    Directory of Open Access Journals (Sweden)

    Sandra Prüller

    Full Text Available Bordetella bronchiseptica causes infections of the respiratory tract in swine and other mammals and is a precursor for secondary infections with Pasteurella multocida. Treatment of B. bronchiseptica infections is conducted primarily with antimicrobial agents. Therefore it is essential to get an overview of the susceptibility status of these bacteria. The aim of this study was to comparatively analyse broth microdilution susceptibility testing according to CLSI recommendations with an incubation time of 16 to 20 hours and a longer incubation time of 24 hours, as recently proposed to obtain more homogenous MICs. Susceptibility testing against a panel of 22 antimicrobial agents and two fixed combinations was performed with 107 porcine isolates from different farms and regions in Germany and 43 isolates obtained from companion animals in Germany and other European countries. Isolates with increased MICs were investigated by PCR assays for the presence of resistance genes. For ampicillin, all 107 porcine isolates were classified as resistant, whereas only a single isolate was resistant to florfenicol. All isolates obtained from companion animals showed elevated MICs for β-lactam antibiotics and demonstrated an overall low susceptibility to cephalosporines. Extension of the incubation time resulted in 1-2 dilution steps higher MIC50 values of porcine isolates for seven antimicrobial agents tested, while isolates from companion animals exhibited twofold higher MIC50/90 values only for tetracycline and cefotaxime. For three antimicrobial agents, lower MIC50 and MIC90 values were detected for both, porcine and companion animal isolates. Among the 150 isolates tested, the resistance genes blaBOR-1 (n = 147, blaOXA-2, (n = 4, strA and strB (n = 17, sul1 (n = 10, sul2 (n = 73, dfrA7 (n = 3 and tet(A (n = 8 were detected and a plasmid localisation was identified for several of the resistance genes.

  11. Relationship between antimicrobial resistance and aminoglycoside-modifying enzyme gene expressions in Acinetobacter baumannii

    Institute of Scientific and Technical Information of China (English)

    SHI Wei-feng; JIANG Jian-ping; MI Zu-huang

    2005-01-01

    Background Acinetobacter baumannii is one of the main gram-negative bacilli in clinical practice. Nosocomial infections caused by multi-drug resistance Acinetobacter baumannii is very difficult to treat. This study was designed to investigate the antimicrobial resistance characteristics and four resistant gene expressions of aminoglycoside-modifying enzymes including N-acetyltransferases and O-phosphotransferases in Acinetobacter baumannii. Methods Bacterial identification and antimicrobial susceptibility test were performed by PhoenixTM system in 247 strains of Acinetobacter baumannii. Minimal inhibitory concentrations (MICs) of seven aminoglycosides including gentamicin, amikacin, kanamycin, tobramycin, netilmicin, neomycin and streptomycin in 15 strains of multi-drug resistant Acinetobacter baumannii were detected by agar dilution. Four aminoglycoside-modifying enzyme genes were amplified by polymerase chain reaction (PCR) and verified by DNA sequencer.Results The resistance rates of 247 strains of Acinetobacter baumannii against cefotaxime, levofloxacin, piperacillin, aztreonam, tetracycline, ciprofloxacin and chloramphenicol were more than 50%. Imipenem and meropenem showed high antibacterial activities with resistance rates of 3.2% and 4.1%. MIC50 and MIC90 of gentamicin, amikacin, streptomycin and kanamycin in 15 strains of multi-drug resistant Acinetobacter baumanii were all more than 1024 mg/L, and the resistance rates were 100%, 100%, 100% and 93.3%, respectively. But their resistance rates to tobramycin, netilmicin and neomycin were 86.7%, 93.3% and 46.7%, respectively. Three modifying enzyme genes, including aacC1, aacC2 and aacA4 genes, were found in 15 strains, but aphA6 had not been detected. Their positive rates were 93.3%, 20.0% and 20.0%, respectively. These three genes existed simultaneously in No.19 strain. Nucleotide sequences of aacC1, aacC2 and aacA4 genes shared 100%, 97.9% and 99.7% identities with GenBank genes (AY307113, S68058 and AY

  12. Toxigenic genes, spoilage potential, and antimicrobial resistance of Bacillus cereus group strains from ice cream.

    Science.gov (United States)

    Arslan, Seza; Eyi, Ayla; Küçüksarı, Rümeysa

    2014-02-01

    Bacillus spp. can be recovered from almost every environment. It is also found readily in foods, where it may cause food spoilage and/or food poisoning due to its toxigenic and pathogenic nature, and extracellular enzymes. In this study, 29 Bacillus cereus group strains from ice cream were examined for the presence of following virulence genes hblC, nheA, cytK and ces genes, and tested for a range of the extracellular enzymes, and antimicrobial susceptibility. The strains were found to produce extracellular enzymes: proteolytic and lipolytic activity, gelatin hydrolysis and lecithinase production (100%), DNase production (93.1%) and amylase activity (93.1%). Of 29 strains examined, 24 (82.8%) showed hemolytic activity on blood agar. Beta-lactamase enzyme was only produced by 20.7% of B. cereus group. Among 29 B. cereus group from ice cream, nheA was the most common virulence gene detected in 44.8% of the strains, followed by hblC gene with 17.2%. Four (13.8%) of the 29 strains were positive for both hblC gene and nheA gene. Contrarily, cytK and ces genes were not detected in any of the strains. Antimicrobial susceptibility of ice cream isolates was tested to 14 different antimicrobial agents using the disc diffusion method. We detected resistance to penicillin and ampicillin with the same rate of 89.7%. Thirty-one percent of the strains were multiresistant to three or more antibiotics. This study emphasizes that the presence of natural isolates of Bacillus spp. harboring one or more enterotoxin genes, producing extracellular enzymes which may cause spoilage and acquiring antibiotic resistance might hold crucial importance in the food safety and quality. PMID:24309214

  13. Characterization of Antimicrobial Resistance Patterns and Detection of Virulence Genes in Campylobacter Isolates in Italy

    Directory of Open Access Journals (Sweden)

    Elisabetta Di Giannatale

    2014-02-01

    Full Text Available Campylobacter has developed resistance to several antimicrobial agents over the years, including macrolides, quinolones and fluoroquinolones, becoming a significant public health hazard. A total of 145 strains derived from raw milk, chicken faeces, chicken carcasses, cattle faeces and human faeces collected from various Italian regions, were screened for antimicrobial susceptibility, molecular characterization (SmaI pulsed-field gel electrophoresis and detection of virulence genes (sequencing and DNA microarray analysis. The prevalence of C. jejuni and C. coli was 62.75% and 37.24% respectively. Antimicrobial susceptibility revealed a high level of resistance for ciprofloxacin (62.76%, tetracycline (55.86% and nalidixic acid (55.17%. Genotyping of Campylobacter isolates using PFGE revealed a total of 86 unique SmaI patterns. Virulence gene profiles were determined using a new microbial diagnostic microarray composed of 70-mer oligonucleotide probes targeting genes implicated in Campylobacter pathogenicity. Correspondence between PFGE and microarray clusters was observed. Comparisons of PFGE and virulence profiles reflected the high genetic diversity of the strains examined, leading us to speculate different degrees of pathogenicity inside Campylobacter populations.

  14. Identification of antimicrobial resistance genes in multidrug-resistant clinical Bacteroides fragilis isolates by whole genome shotgun sequencing

    DEFF Research Database (Denmark)

    Sydenham, Thomas Vognbjerg; Sóki, József; Hasman, Henrik;

    2015-01-01

    Bacteroides fragilis constitutes the most frequent anaerobic bacterium causing bacteremia in humans. The genetic background for antimicrobial resistance in B. fragilis is diverse with some genes requiring insertion sequence (IS) elements inserted upstream for increased expression. To evaluate whole...... genetic data will most likely require complete or nearly complete genomes. Current approaches to this are laborious and/or costly. Emerging technologies such as nanopore based single DNA strand sensing could perhaps provide a solution in the future....

  15. Antimicrobial resistance of thermophilic Campylobacter

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Engberg, J.

    2001-01-01

    Campylobacter has become the leading cause of zoonotic enteric infections in developed and developing countries world-wide. Antimicrobial resistance has emerged among Campylobacter mainly as a consequence of the use of antimicrobial agents in food animal production. Resistance to drugs of choice...... for the treatment of infections, macrolides and fluoroquinolones has emerged as a clinical problem and interventions to reduce this are recommended. Resistance to fluoroquinolones and macrolides is mediated by chromosomal mutations. Resistance to other relevant antimicrobial agents, mediated by...... acquired resistance genes, has not become widespread so far. However, resistance genes originating from both Gram-positive and Gram-negative bacterial species have been found, showing the potential for acquired resistance to emerge in Campylobacter....

  16. Unraveling Antimicrobial Resistance Genes and Phenotype Patterns among Enterococcus faecalis Isolated from Retail Chicken Products in Japan

    OpenAIRE

    Arata Hidano; Takehisa Yamamoto; Yoko Hayama; Norihiko Muroga; Sota Kobayashi; Takeshi Nishida; Toshiyuki Tsutsui

    2015-01-01

    Multidrug-resistant enterococci are considered crucial drivers for the dissemination of antimicrobial resistance determinants within and beyond a genus. These organisms may pass numerous resistance determinants to other harmful pathogens, whose multiple resistances would cause adverse consequences. Therefore, an understanding of the coexistence epidemiology of resistance genes is critical, but such information remains limited. In this study, our first objective was to determine the prevalence...

  17. Animation of Antimicrobial Resistance

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    Full Text Available ... Translation - Animation of Antimicrobial Resistance (WMV - 19.2MB) Chinese Translation - Animation of Antimicrobial Resistance (WMV - 19.2MB) ... FEAR Act Site Map Transparency Website Policies U.S. Food and Drug Administration 10903 New Hampshire Avenue Silver ...

  18. Prevalence, toxin gene profiles, and antimicrobial resistance of Staphylococcus aureus isolated from quick-frozen dumplings.

    Science.gov (United States)

    Hao, Dan; Xing, Xiaonan; Li, Guanghui; Wang, Xin; Zhang, Min; Zhang, Weisong; Xia, Xiaodong; Meng, Jianghong

    2015-01-01

    The aim of this study was to investigate the prevalence of Staphylococcus aureus in quick-frozen dumplings and to characterize these strains. A total of 120 dumpling samples, including lamb (n = 13), vegetarian (n = 14), seafood (n = 12), and pork (n = 81) stuffing, were collected in Shaanxi province in China and screened for S. aureus. All S. aureus isolates were characterized by antimicrobial susceptibility testing, and detection of genes encoding staphylococcal enterotoxins, exfoliative toxins A and B (eta and etb), toxic shock syndrome toxin 1 (tsst-1), and resistance to methicillin-oxacillin (mecA). In all, 60.0% of all samples were positive for S. aureus, and 117 S. aureus isolates, including seven mecA-positive strains, were recovered from these positive samples. In addition, all mecA-positive S. aureus isolates were recovered from products of animal origin. In these S. aureus isolates, resistance was observed most frequently to ampicillin (92.3%) and penicillin (86.3%), followed by clarithromycin, erythromycin, midecamycin, tetracycline, and kanahemycin (from 53.8 to 28.2%). All isolates were sensitive to cefoperazone, minocycline, vancomycin, and ofloxacin. The predominant toxin gene was sec (38.5%), followed by seg (19.7%), sej (16.2%), see (12.8%), sea (11.1%), and seb (10.3%), whereas eta, etb, and tsst-1 genes were not detected. These findings indicate that S. aureus was present commonly in quick-frozen dumplings, accompanied by multiple antimicrobial resistance and toxin genes. Our findings highlight the urgency for stricter hygiene strategies in food production and the prudent use of antibiotics in the breeding industry.

  19. Animation of Antimicrobial Resistance

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    Full Text Available ... use of antimicrobial drugs will result in the development of resistant strains of bacteria, complicating clinician's efforts to select the appropriate antimicrobial for treatment. Accordingly, efforts are underway in both veterinary and human medicine to preserve the effectiveness of these drugs. ...

  20. Animation of Antimicrobial Resistance

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    Full Text Available ... use of antimicrobial drugs will result in the development of resistant strains of bacteria, complicating clinician's efforts ... Emergency Preparedness International Programs News & Events Training & Continuing Education Inspections & Compliance Federal, State & Local Officials Consumers Health ...

  1. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... issue of antimicrobial resistance is that the subject material appears abstract and is complex. This video was ... can develop and spread. All FDA CVM produced material may be copied, reproduced, and distributed as long ...

  2. Antimicrobial resistance in wildlife

    OpenAIRE

    Vittecoq, M.; Godreuil, S.; Prugnolle, Franck; Durand, P.; Brazier, L; Renaud, N; Arnal, A.; Aberkane, S.; Jean-Pierre, H.; Gauthier-Clerc, M; Thomas, F.; Renaud, F.

    2016-01-01

    The spread of antimicrobial resistance is of major concern for human health and leads to growing economic costs. While it is increasingly hypothesized that wildlife could play an important role in antimicrobial-resistant bacteria dynamics, empirical data remain scarce. The present work builds on a systematic review of the available data in order to highlight the main information we have and to suggest research pathways that should be followed if we aim to fill the gaps in our current knowledg...

  3. Correlation between Group B Streptococcal Genotypes, Their Antimicrobial Resistance Profiles, and Virulence Genes among Pregnant Women in Lebanon

    Directory of Open Access Journals (Sweden)

    Antoine Hannoun

    2009-01-01

    Full Text Available The antimicrobial susceptibility profiles of 76 Streptococcus agalactiae (Group B Streptococci [GBS] isolates from vaginal specimens of pregnant women near term were correlated to their genotypes generated by Random Amplified Polymorphic DNA analysis and their virulence factors encoding genes cylE, lmb, scpB, rib, and bca by PCR. Based on the distribution of the susceptibility patterns, six profiles were generated. RAPD analysis detected 7 clusters of genotypes. The cylE gene was present in 99% of the isolates, the lmb in 96%, scpB in 94.7%, rib in 33%, and bca in 56.5% of isolates. The isolates demonstrated a significant correlation between antimicrobial resistance and genotype clusters denoting the distribution of particular clones with different antimicrobial resistance profiles, entailing the practice of caution in therapeutic options. All virulence factors encoding genes were detected in all seven genotypic clusters with rib and bca not coexisting in the same genome.

  4. Characterisation of antimicrobial resistance-associated integrons and mismatch repair gene mutations in Salmonella serotypes.

    Science.gov (United States)

    Yang, Baowei; Zheng, Jie; Brown, Eric W; Zhao, Shaohua; Meng, Jianghong

    2009-02-01

    In this study, we examined the presence of integrons and Salmonella genomic island 1 (SGI1) and assessed their contribution to antimicrobial resistance as well as determining the extent of the mutator phenotype in Salmonella isolates. A total of 81 Salmonella enterica serotype Typhimurium isolates were examined for the presence of integrons and SGI1 and for hypermutators using polymerase chain reaction (PCR) and the mutator assay, respectively. An additional 336 Salmonella isolates were also used to screen for hypermutators. Fourteen S. Typhimurium isolates carried class 1 integrons, of which six were shown to possess SGI1. Five putative mutators, S. Typhimurium ST20751, S. enterica serotype Heidelberg 22396 and S. enterica serotype Enteritidis 17929, 17929N and 17929R, were identified among the 417 Salmonella isolates. Complementation analysis with the wild-type mutH, mutL, mutS and uvrD genes indicated that none of the five mutators contained defective mismatch repair (MMR) system alleles. DNA sequence analysis revealed that single point mutations resulting in aspartic acid (codon 87) substitution in the gyrA gene conferred resistance to nalidixic acid and/or other fluoroquinolone drugs (ciprofloxacin and enrofloxacin) among four isolates. Our findings indicated that integrons and SGI1 play an important role in multidrug resistance in Salmonella. The incidence of hypermutators owing to defective MMR in Salmonella appears to be rare. PMID:19013057

  5. Lipopolysaccharide Biosynthesis Genes of Yersinia pseudotuberculosis Promote Resistance to Antimicrobial Chemokines

    Science.gov (United States)

    Erickson, David L.; Lew, Cynthia S.; Kartchner, Brittany; Porter, Nathan T.; McDaniel, S. Wade; Jones, Nathan M.; Mason, Sara; Wu, Erin; Wilson, Eric

    2016-01-01

    Antimicrobial chemokines (AMCs) are a recently described family of host defense peptides that play an important role in protecting a wide variety of organisms from bacterial infection. Very little is known about the bacterial targets of AMCs or factors that influence bacterial susceptibility to AMCs. In an effort to understand how bacterial pathogens resist killing by AMCs, we screened Yersinia pseudotuberculosis transposon mutants for those with increased binding to the AMCs CCL28 and CCL25. Mutants exhibiting increased binding to AMCs were subjected to AMC killing assays, which revealed their increased sensitivity to chemokine-mediated cell death. The majority of the mutants exhibiting increased binding to AMCs contained transposon insertions in genes related to lipopolysaccharide biosynthesis. A particularly strong effect on susceptibility to AMC mediated killing was observed by disruption of the hldD/waaF/waaC operon, necessary for ADP-L-glycero-D-manno-heptose synthesis and a complete lipopolysaccharide core oligosaccharide. Periodate oxidation of surface carbohydrates also enhanced AMC binding, whereas enzymatic removal of surface proteins significantly reduced binding. These results suggest that the structure of Y. pseudotuberculosis LPS greatly affects the antimicrobial activity of AMCs by shielding a protein ligand on the bacterial cell surface. PMID:27275606

  6. Lipopolysaccharide Biosynthesis Genes of Yersinia pseudotuberculosis Promote Resistance to Antimicrobial Chemokines.

    Directory of Open Access Journals (Sweden)

    David L Erickson

    Full Text Available Antimicrobial chemokines (AMCs are a recently described family of host defense peptides that play an important role in protecting a wide variety of organisms from bacterial infection. Very little is known about the bacterial targets of AMCs or factors that influence bacterial susceptibility to AMCs. In an effort to understand how bacterial pathogens resist killing by AMCs, we screened Yersinia pseudotuberculosis transposon mutants for those with increased binding to the AMCs CCL28 and CCL25. Mutants exhibiting increased binding to AMCs were subjected to AMC killing assays, which revealed their increased sensitivity to chemokine-mediated cell death. The majority of the mutants exhibiting increased binding to AMCs contained transposon insertions in genes related to lipopolysaccharide biosynthesis. A particularly strong effect on susceptibility to AMC mediated killing was observed by disruption of the hldD/waaF/waaC operon, necessary for ADP-L-glycero-D-manno-heptose synthesis and a complete lipopolysaccharide core oligosaccharide. Periodate oxidation of surface carbohydrates also enhanced AMC binding, whereas enzymatic removal of surface proteins significantly reduced binding. These results suggest that the structure of Y. pseudotuberculosis LPS greatly affects the antimicrobial activity of AMCs by shielding a protein ligand on the bacterial cell surface.

  7. High prevalence of multidrug-tolerant bacteria and associated antimicrobial resistance genes isolated from ornamental fish and their carriage water.

    Directory of Open Access Journals (Sweden)

    David W Verner-Jeffreys

    Full Text Available BACKGROUND: Antimicrobials are used to directly control bacterial infections in pet (ornamental fish and are routinely added to the water these fish are shipped in to suppress the growth of potential pathogens during transport. METHODOLOGY/PRINCIPAL FINDINGS: To assess the potential effects of this sustained selection pressure, 127 Aeromonas spp. isolated from warm and cold water ornamental fish species were screened for tolerance to 34 antimicrobials. Representative isolates were also examined for the presence of 54 resistance genes by a combination of miniaturized microarray and conventional PCR. Forty-seven of 94 Aeromonas spp. isolates recovered from tropical ornamental fish and their carriage water were tolerant to > or =15 antibiotics, representing seven or more different classes of antimicrobial. The quinolone and fluoroquinolone resistance gene, qnrS2, was detected at high frequency (37% tested recent isolates were positive by PCR. Class 1 integrons, IncA/C broad host range plasmids and a range of other antibiotic resistance genes, including floR, bla(TEM-1, tet(A, tet(D, tet(E, qacE2, sul1, and a number of different dihydrofolate reductase and aminoglycoside transferase coding genes were also detected in carriage water samples and bacterial isolates. CONCLUSIONS: These data suggest that ornamental fish and their carriage water act as a reservoir for both multi-resistant bacteria and resistance genes.

  8. CHARACTERIZATION OF VIRULENCE GENES AND ANTIMICROBIAL RESISTANCE OF LUNG PATHOGENIC ESCHERICHIA COLI ISOLATES IN FOREST MUSK DEER (MOSCHUS BEREZOVSKII).

    Science.gov (United States)

    Luo, Xi; Wang, Peng; Cheng, Jian-guo; Luo, Yan; Dai, Lei; Zhou, Xin; Zou, Li-kou; Li, Bei; Xiao, Jiu-Jin

    2016-06-01

    This study investigated genotypic diversity, 26 virulence genes, and antimicrobial susceptibility of lung pathogenic Escherichia coli (LPEC) isolated from forest musk deer. Associations between virulence factors (VFs) and phylogenetic group, between antimicrobial resistance (AMR) and phylogenetic group, and between AMR and VFs were subsequently assessed. The results showed 30 LPEC isolated were grouped into seven different clusters (A, B, C, D, E, F, and G). The detection rates of crl (90%), kpsMT II (76.67%), mat (76.67%), and ompA (80%) were over 75%. The most frequent types of resistance were to amoxicillin (100%), sulfafurazole (100%), ampicillin (96.67%), and tetracycline (96.67%), with 93.33% (n = 28) of isolates resistant to more than eight types of drugs. There were significant relationships between resistance to cefalotin and the presence of iucD(a) (P < 0.001), papC (P = 0.032), and kpsMT II (P = 0.028); between resistance to chloromycetin and the presence of irp2 (P = 0.004) and vat (P = 0.047); between resistance to nalidixic acid and the presence of crl (P = 0.002) and iucD(a) (P = 0.004); and between resistance to ampicillin/sulbactam and the presence of vat (P = 0.013). These results indicated there could be some association between resistance and VFs, and there is a great need for the prudent use of antimicrobial agents in LPEC.

  9. CHARACTERIZATION OF VIRULENCE GENES AND ANTIMICROBIAL RESISTANCE OF LUNG PATHOGENIC ESCHERICHIA COLI ISOLATES IN FOREST MUSK DEER (MOSCHUS BEREZOVSKII).

    Science.gov (United States)

    Luo, Xi; Wang, Peng; Cheng, Jian-guo; Luo, Yan; Dai, Lei; Zhou, Xin; Zou, Li-kou; Li, Bei; Xiao, Jiu-Jin

    2016-06-01

    This study investigated genotypic diversity, 26 virulence genes, and antimicrobial susceptibility of lung pathogenic Escherichia coli (LPEC) isolated from forest musk deer. Associations between virulence factors (VFs) and phylogenetic group, between antimicrobial resistance (AMR) and phylogenetic group, and between AMR and VFs were subsequently assessed. The results showed 30 LPEC isolated were grouped into seven different clusters (A, B, C, D, E, F, and G). The detection rates of crl (90%), kpsMT II (76.67%), mat (76.67%), and ompA (80%) were over 75%. The most frequent types of resistance were to amoxicillin (100%), sulfafurazole (100%), ampicillin (96.67%), and tetracycline (96.67%), with 93.33% (n = 28) of isolates resistant to more than eight types of drugs. There were significant relationships between resistance to cefalotin and the presence of iucD(a) (P < 0.001), papC (P = 0.032), and kpsMT II (P = 0.028); between resistance to chloromycetin and the presence of irp2 (P = 0.004) and vat (P = 0.047); between resistance to nalidixic acid and the presence of crl (P = 0.002) and iucD(a) (P = 0.004); and between resistance to ampicillin/sulbactam and the presence of vat (P = 0.013). These results indicated there could be some association between resistance and VFs, and there is a great need for the prudent use of antimicrobial agents in LPEC. PMID:27468027

  10. Prevalence of virulence and antimicrobial resistance genes in Salmonella spp. isolated from commercial chickens and human clinical isolates from South Africa and Brazil

    Directory of Open Access Journals (Sweden)

    Oliver T. Zishiri

    2016-03-01

    Full Text Available Salmonellosis is a significant public health concern around the world. The injudicious use of antimicrobial agents in poultry production for treatment, growth promotion and prophylaxis has resulted in the emergence of drug resistant strains of Salmonella. The current study was conducted to investigate the prevalence of virulence and antimicrobial resistance genes from Salmonella isolated from South African and Brazilian broiler chickens as well as human clinical isolates. Out of a total of 200 chicken samples that were collected from South Africa 102 (51% tested positive for Salmonella using the InvA gene. Of the overall 146 Salmonella positive samples that were screened for the iroB gene most of them were confirmed to be Salmonella enterica with the following prevalence rates: 85% of human clinical samples, 68.6% of South African chicken isolates and 70.8% of Brazilian chicken samples. All Salmonella isolates obtained were subjected to antimicrobial susceptibility testing with 10 antibiotics. Salmonella isolates from South African chickens exhibited resistance to almost all antimicrobial agents used, such as tetracycline (93%, trimethoprim-sulfamthoxazole (84%, trimethoprim (78.4%, kanamycin (74%, gentamicin (48%, ampicillin (47%, amoxicillin (31%, chloramphenicol (31%, erythromycin (18% and streptomycin (12%. All samples were further subjected to PCR in order to screen some common antimicrobial and virulence genes of interest namely spiC, pipD, misL, orfL, pse-1, tet A, tet B, ant (3"-la, sul 1 and sul. All Salmonella positive isolates exhibited resistance to at least one antimicrobial agent; however, antimicrobial resistance patterns demonstrated that multiple drug resistance was prevalent. The findings provide evidence that broiler chickens are colonised by pathogenic Salmonella harbouring antimicrobial resistance genes. Therefore, it is evident that there is a need for prudent use of antimicrobial agents in poultry production systems in

  11. Animation of Antimicrobial Resistance

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    Full Text Available ... En Español Search FDA Submit search Popular Content Home Food Drugs Medical Devices Radiation-Emitting Products Vaccines, ... Biologics Animal & Veterinary Cosmetics Tobacco Products Animal & Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of ...

  12. Antimicrobial susceptibility and presence of resistance genes in staphylococci from poultry

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Agersø, Yvonne; Ahrens, Peter;

    2000-01-01

    to ciprofloxacin. Only six (7%) S. aureus isolates and one Staphylococcus saprophyticus were penicillin resistant. Resistance to sulphamethoxazole was observed among 16 (19%) of S. aureus isolates and two coagulase negative staphylococci (CNS). Twenty (24%) of the S. aureus isolates were resistant to erythromycin...... of conventional biochemical testing and 16S rDNA sequencing. The most common species were Staphylococcus aureus (83), Staphylococcus hyicus (11), Staphylococcus xylosus (9) and Staphylococcus cohnii (6). The isolates were susceptible to most antimicrobials tested. A high frequency of S. aureus (30%) was resistant...

  13. Comparison of antimicrobial resistance phenotypes and resistance genes in Enterococcus faecalis and Enterococcus faecium from humans in the community, broilers and pigs in Denmark

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Agersø, Yvonne; Gerner-Smidt, P.;

    2000-01-01

    Enterococcus faecalis and E. faecium isolated from humans in the community (98 and 65 isolates), broilers (126 and 122), and pigs (102 and 88) during 1998 were tested for susceptibility to 12 different antimicrobial agents and for the presence of selected genes encoding resistance using PCR...

  14. Unraveling antimicrobial resistance genes and phenotype patterns among Enterococcus faecalis isolated from retail chicken products in Japan.

    Science.gov (United States)

    Hidano, Arata; Yamamoto, Takehisa; Hayama, Yoko; Muroga, Norihiko; Kobayashi, Sota; Nishida, Takeshi; Tsutsui, Toshiyuki

    2015-01-01

    Multidrug-resistant enterococci are considered crucial drivers for the dissemination of antimicrobial resistance determinants within and beyond a genus. These organisms may pass numerous resistance determinants to other harmful pathogens, whose multiple resistances would cause adverse consequences. Therefore, an understanding of the coexistence epidemiology of resistance genes is critical, but such information remains limited. In this study, our first objective was to determine the prevalence of principal resistance phenotypes and genes among Enterococcus faecalis isolated from retail chicken domestic products collected throughout Japan. Subsequent analysis of these data by using an additive Bayesian network (ABN) model revealed the co-appearance patterns of resistance genes and identified the associations between resistance genes and phenotypes. The common phenotypes observed among E. faecalis isolated from the domestic products were the resistances to oxytetracycline (58.4%), dihydrostreptomycin (50.4%), and erythromycin (37.2%), and the gene tet(L) was detected in 46.0% of the isolates. The ABN model identified statistically significant associations between tet(L) and erm(B), tet(L) and ant(6)-Ia, ant(6)-Ia and aph(3')-IIIa, and aph(3')-IIIa and erm(B), which indicated that a multiple-resistance profile of tetracycline, erythromycin, streptomycin, and kanamycin is systematic rather than random. Conversely, the presence of tet(O) was only negatively associated with that of erm(B) and tet(M), which suggested that in the presence of tet(O), the aforementioned multiple resistance is unlikely to be observed. Such heterogeneity in linkages among genes that confer the same phenotypic resistance highlights the importance of incorporating genetic information when investigating the risk factors for the spread of resistance. The epidemiological factors that underlie the persistence of systematic multiple-resistance patterns warrant further investigations with appropriate

  15. Unraveling antimicrobial resistance genes and phenotype patterns among Enterococcus faecalis isolated from retail chicken products in Japan.

    Directory of Open Access Journals (Sweden)

    Arata Hidano

    Full Text Available Multidrug-resistant enterococci are considered crucial drivers for the dissemination of antimicrobial resistance determinants within and beyond a genus. These organisms may pass numerous resistance determinants to other harmful pathogens, whose multiple resistances would cause adverse consequences. Therefore, an understanding of the coexistence epidemiology of resistance genes is critical, but such information remains limited. In this study, our first objective was to determine the prevalence of principal resistance phenotypes and genes among Enterococcus faecalis isolated from retail chicken domestic products collected throughout Japan. Subsequent analysis of these data by using an additive Bayesian network (ABN model revealed the co-appearance patterns of resistance genes and identified the associations between resistance genes and phenotypes. The common phenotypes observed among E. faecalis isolated from the domestic products were the resistances to oxytetracycline (58.4%, dihydrostreptomycin (50.4%, and erythromycin (37.2%, and the gene tet(L was detected in 46.0% of the isolates. The ABN model identified statistically significant associations between tet(L and erm(B, tet(L and ant(6-Ia, ant(6-Ia and aph(3'-IIIa, and aph(3'-IIIa and erm(B, which indicated that a multiple-resistance profile of tetracycline, erythromycin, streptomycin, and kanamycin is systematic rather than random. Conversely, the presence of tet(O was only negatively associated with that of erm(B and tet(M, which suggested that in the presence of tet(O, the aforementioned multiple resistance is unlikely to be observed. Such heterogeneity in linkages among genes that confer the same phenotypic resistance highlights the importance of incorporating genetic information when investigating the risk factors for the spread of resistance. The epidemiological factors that underlie the persistence of systematic multiple-resistance patterns warrant further investigations with

  16. Genotypes, Virulence Factors and Antimicrobial Resistance Genes of Staphylococcus aureus Isolated in Bovine Subclinical Mastitis from Eastern China

    Directory of Open Access Journals (Sweden)

    Javed Memon§, Yongchun Yang§, Jam Kashifa, Muhammad Yaqoob, Rehana Buriroa, Jamila Soomroa, Wang Liping and Fan Hongjie*

    2013-11-01

    Full Text Available This study was carried out to determine the genotypes, virulence factors and antimicrobial resistance traits of 34 Staphylococcus aureus isolated from subclinical mastitis in Eastern China. Minimal inhibitory concentration (MIC results showed resistance to erythromycin in all isolates. A high frequency of Methicillin resistant S. aureus (MRSA; 29% was observed and these isolates were also highly resistant to penicillin, oxacillin, oxytetracycline and chloramphenicol than methicillin sensitive S. aureus (MSSA isolates. Thirteen pathogenic factors and seven resistance genes including mecA and blaZ gene were checked through PCR. The spaX gene was found in all isolates, whereas cna, spaIg, nuc, clfA, fnbpB, hlA, hlB and seA were present in 35, 79, 85, 59, 35, 85, 71 and 38% isolates, respectively. Nine isolates carried a group of 8 different virulence genes. Moreover, macrolide resistance genes ermB and ermC were present in all isolates. High resistance rate against methicillin was found but no isolate was positive for mecA gene, whereas blaZ and tetK were detected in 82 and 56% isolates, respectively. Genes; fnbpA, seB, seC, seD, dfrK and tetM were not found in any isolate. The statistical association between phenotypic resistance and virulence genes showed, clfA, fnbpB, hlB and seA, were potentially associated with penicillin G, ciprofloxacin, methicillin, chloramphenicol, trimethoprim and oxytetracycline resistance (P≤0.05. REP-PCR based genotyping showed seven distinct genotypes (A-G prevalent in this region. This study reports the presence of multidrug resistant S. aureus in sub-clinical mastitis which were also highly virulent that could be a major obstacle in the treatment of mastitis in this region of China.

  17. Prevalence of virulence and antimicrobial resistance genes in Salmonella spp. isolated from commercial chickens and human clinical isolates from South Africa and Brazil.

    Science.gov (United States)

    Zishiri, Oliver T; Mkhize, Nelisiwe; Mukaratirwa, Samson

    2016-01-01

    Salmonellosis is a significant public health concern around the world. The injudicious use of antimicrobial agents in poultry production for treatment, growth promotion and prophylaxis has resulted in the emergence of drug resistant strains of Salmonella. The current study was conducted to investigate the prevalence of virulence and antimicrobial resistance genes from Salmonella isolated from South African and Brazilian broiler chickens as well as human clinical isolates. Out of a total of 200 chicken samples that were collected from South Africa 102 (51%) tested positive for Salmonella using the InvA gene. Of the overall 146 Salmonella positive samples that were screened for the iroB gene most of them were confirmed to be Salmonella enterica with the following prevalence rates: 85% of human clinical samples, 68.6% of South African chicken isolates and 70.8% of Brazilian chicken samples. All Salmonella isolates obtained were subjected to antimicrobial susceptibility testing with 10 antibiotics. Salmonella isolates from South African chickens exhibited resistance to almost all antimicrobial agents used, such as tetracycline (93%), trimethoprim-sulfamthoxazole (84%), trimethoprim (78.4%), kanamycin (74%), gentamicin (48%), ampicillin (47%), amoxicillin (31%), chloramphenicol (31%), erythromycin (18%) and streptomycin (12%). All samples were further subjected to PCR in order to screen some common antimicrobial and virulence genes of interest namely spiC, pipD, misL, orfL, pse-1, tet A, tet B, ant (3")-la, sul 1 and sul. All Salmonella positive isolates exhibited resistance to at least one antimicrobial agent; however, antimicrobial resistance patterns demonstrated that multiple drug resistance was prevalent. The findings provide evidence that broiler chickens are colonised by pathogenic Salmonella harbouring antimicrobial resistance genes. Therefore, it is evident that there is a need for prudent use of antimicrobial agents in poultry production systems in order to

  18. Salmonella enterica serovar enteritidis antimicrobial peptide resistance genes aid in defense against chicken innate immunity, fecal shedding, and egg deposition.

    Science.gov (United States)

    McKelvey, Jessica A; Yang, Ming; Jiang, Yanhua; Zhang, Shuping

    2014-12-01

    Salmonella enterica serovar Enteritidis (S. Enteritidis) is a major etiologic agent of nontyphoid salmonellosis in the United States. S. Enteritidis persistently and silently colonizes the intestinal and reproductive tract of laying hens, resulting in contaminated poultry products. The consumption of contaminated poultry products has been identified as a significant risk factor for human salmonellosis. To understand the mechanisms S. Enteritidis utilizes to colonize and persist in laying hens, we used selective capture of transcribed sequences to identify genes overexpressed in the HD11 chicken macrophage cell line and in primary chicken oviduct epithelial cells. From the 15 genes found to be overexpressed in both cell types, we characterized the antimicrobial peptide resistance (AMPR) genes, virK and ybjX, in vitro and in vivo. In vitro, AMPR genes were required for natural morphology, motility, secretion, defense against detergents such as EDTA and bile salts, and resistance to antimicrobial peptides polymyxin B and avian β-defensins. From this, we inferred the AMPR genes play a role in outer membrane stability and/or modulation. In the intestinal tract, AMPR genes were involved in early intestinal colonization and fecal shedding. In the reproductive tract, virK was required in early colonization whereas a deletion of ybjX caused prolonged ovary colonization and egg deposition. Data from the present study indicate that AMPR genes are differentially utilized in various host environments, which may ultimately assist S. Enteritidis in persistent and silent colonization of chickens.

  19. Lipopolysaccharide Biosynthesis Genes of Yersinia pseudotuberculosis Promote Resistance to Antimicrobial Chemokines

    OpenAIRE

    Erickson, David L.; Lew, Cynthia S.; Brittany Kartchner; Porter, Nathan T.; S Wade McDaniel; Jones, Nathan M.; Sara Mason; Erin Wu; Eric Wilson

    2016-01-01

    Antimicrobial chemokines (AMCs) are a recently described family of host defense peptides that play an important role in protecting a wide variety of organisms from bacterial infection. Very little is known about the bacterial targets of AMCs or factors that influence bacterial susceptibility to AMCs. In an effort to understand how bacterial pathogens resist killing by AMCs, we screened Yersinia pseudotuberculosis transposon mutants for those with increased binding to the AMCs CCL28 and CCL25....

  20. Presence of superantigen genes and antimicrobial resistance in Staphylococcus isolates obtained from the uteri of dairy cows with clinical endometritis.

    Science.gov (United States)

    Zhao, J-L; Ding, Y-X; Zhao, H-X; He, X-L; Li, P-F; Li, Z-F; Guan, H; Guo, X

    2014-10-11

    Clinical endometritis is an important disease of dairy cattle and results in decreased reproductive performance. This disease is caused by contamination of the uterus with a broad spectrum of microorganisms after calving. In this study, staphylococcal isolates from the uterus of dairy cows with clinical endometritis were tested for their distribution of superantigen (SAg) genes and antimicrobial resistance. Between the 127 staphylococcal isolates collected in this study, 10 species were identified. The predominant strain identified was Staphylococcus aureus (n=53), followed by Staphylococcus saprophyticus (n=38) and Staphylococcus chromogenes (n=22). PCR analysis demonstrated that most isolates (63.0 per cent) harboured at least one SAg gene. The most commonly observed SAg gene and genotype was selj (38.6 per cent) and sec-selj-seln (24.0 per cent), respectively. Most isolates were resistant to penicillin (79.5 per cent), ampicillin (71.7 per cent), erythromycin (56.7 per cent), and tetracycline (52.0 per cent). PCR analysis demonstrated that the antimicrobial resistance determinants ermA, ermB, ermC, tetK, tetM and blaZ were detected in 0 per cent, 44.4 per cent, 51.4 per cent, 68.2 per cent, 13.6 per cent and 86.1 per cent of the erythromycin, tetracycline and β-lactam resistant isolates, respectively. There were 22 (17.3 per cent of all isolates) coagulase-negative staphylococci shown to be methicillin resistant. In the methicillin-resistant isolates, significant resistances to ampicillin, erythromycin and penicillin were observed (P<0.01). The results of this study demonstrate that staphylococci recovered from dairy cows with clinical endometritis contain an extensive and complex prevalence of SAg genes. Significant resistances to antibiotics were also seen, highlighting the need for the rational appliance of antibiotics in veterinary medicine.

  1. Presence of superantigen genes and antimicrobial resistance in Staphylococcus isolates obtained from the uteri of dairy cows with clinical endometritis.

    Science.gov (United States)

    Zhao, J-L; Ding, Y-X; Zhao, H-X; He, X-L; Li, P-F; Li, Z-F; Guan, H; Guo, X

    2014-10-11

    Clinical endometritis is an important disease of dairy cattle and results in decreased reproductive performance. This disease is caused by contamination of the uterus with a broad spectrum of microorganisms after calving. In this study, staphylococcal isolates from the uterus of dairy cows with clinical endometritis were tested for their distribution of superantigen (SAg) genes and antimicrobial resistance. Between the 127 staphylococcal isolates collected in this study, 10 species were identified. The predominant strain identified was Staphylococcus aureus (n=53), followed by Staphylococcus saprophyticus (n=38) and Staphylococcus chromogenes (n=22). PCR analysis demonstrated that most isolates (63.0 per cent) harboured at least one SAg gene. The most commonly observed SAg gene and genotype was selj (38.6 per cent) and sec-selj-seln (24.0 per cent), respectively. Most isolates were resistant to penicillin (79.5 per cent), ampicillin (71.7 per cent), erythromycin (56.7 per cent), and tetracycline (52.0 per cent). PCR analysis demonstrated that the antimicrobial resistance determinants ermA, ermB, ermC, tetK, tetM and blaZ were detected in 0 per cent, 44.4 per cent, 51.4 per cent, 68.2 per cent, 13.6 per cent and 86.1 per cent of the erythromycin, tetracycline and β-lactam resistant isolates, respectively. There were 22 (17.3 per cent of all isolates) coagulase-negative staphylococci shown to be methicillin resistant. In the methicillin-resistant isolates, significant resistances to ampicillin, erythromycin and penicillin were observed (P<0.01). The results of this study demonstrate that staphylococci recovered from dairy cows with clinical endometritis contain an extensive and complex prevalence of SAg genes. Significant resistances to antibiotics were also seen, highlighting the need for the rational appliance of antibiotics in veterinary medicine. PMID:24989035

  2. Development of a miniaturised microarray-based assay for the rapid identification of antimicrobial resistance genes in Gram-negative bacteria

    NARCIS (Netherlands)

    Batchelor, M.; Hopkins, K.L.; Liebana, E.; Slickers, P.; Ehricht, R.; Mafura, M.; Aerestrup, F.; Mevius, D.J.; Clifton-Hadley, F.A.; Woodward, M.; Davies, R.; Threlfall, J.; Anjum, F.M.

    2008-01-01

    We describe the development of a miniaturised microarray for the detection of antimicrobial resistance genes in Gram-negative bacteria. Included on the array are genes encoding resistance to aminoglycosides, trimethoprim, sulphonamides, tetracyclines and ß-lactams, including extended-spectrum ß-lact

  3. [Neruda and antimicrobial resistance].

    Science.gov (United States)

    Cotera, Alejandro

    2011-07-01

    Antimicrobial resistance has been a problem in medicine, since their incorporation to clinical practice. Numerous papers have been written on the subject. The analysis of two poems by Pablo Neruda "How much does a man live" and "Larynx", included in the volume "Estravagario" and published for the first time in 1957 and 1958, give us an incredible revelation about the concept of resistance. In these poems aureomycin, the first antimicrobial of the family of tetracyclines, was included as a poetic figure and the therapeutic action of antimicrobials was described. "Never so much bugs died I tons of them fell I but the few that remained olive I manifested their perversity". These writings incorporated novel concepts, even for physicians of that time and described the closeness of death that a patient may perceive during the course of a given disease. The capacity of Pablo Neruda to extract the essence of situations and to anticipate to conditions that only years later became clinically relevant problems, is noteworthy.

  4. Characterization of antimicrobial resistance and virulence genes in Enterococcus spp. isolated from retail meats in Alberta, Canada.

    Science.gov (United States)

    Aslam, Mueen; Diarra, Moussa S; Checkley, Sylvia; Bohaychuk, Valerie; Masson, Luke

    2012-06-01

    The objective of this study was to characterize antimicrobial resistance (AMR) and virulence genotypes of Enterococcus spp. particularly Enterococcus faecalis isolated from retail meats purchased (2007-2008) in Alberta, Canada. Unconditional statistical associations between AMR pheno- and genotypes and virulence genotypes were determined. A total of 532 enterococci comprising one isolate from each positive sample were analyzed for antimicrobial susceptibility. A customized enterococcal microarray was used for species identification and the detection of AMR and virulence genes. E. faecalis was found in >94% of poultry samples and in about 73% of beef and 86% of pork samples. Enterococcus faecium was not found in turkey meat and its prevalence was 2% in beef and pork and 4% in chicken samples. None of the enterococci isolates were resistant to the clinically important drugs ciprofloxacin, daptomycin, linezolid and vancomycin. Multiresistance (≥3 antimicrobials) was more common in E. faecalis (91%) isolated from chicken and turkey (91%) than those isolated from beef (14%) or pork (45%). Resistance to aminoglycosides was also noted at varying degrees. The most common resistance genes found in E. faecalis were aminoglycosides (aac, aphA3, aadE, sat4, aadA), macrolides (ermB, ermA), tetracyclines (tetM, tetL, tetO), streptogramin (vatE), bacitracin (bcrR) and lincosamide (linB). Virulence genes expressing aggregation substances (agg) and cytolysin (cylA, cylB, cylL, cylM) were found more frequently in poultry E. faecalis and were unconditionally associated with tetM, linB and bcrR resistance genes. Other virulence genes coding for adhesion (ace, efaAfs), gelatinase (gelE) were also found in the majority of E. faecalis. Significant statistical associations were found between resistance and virulence genotypes, suggesting their possible physical link on a common genetic element. This study underscores the importance of E. faecalis as a reservoir of resistance and

  5. Antimicrobial susceptibility and occurrence of resistance genes among Salmonella enterica serovar Weltevreden from different countries

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Lertworapreecha, M.; Evans, M.C.;

    2003-01-01

    towards ampicillin (1.8%), chloramphenicol (1.6%), florphenicol (0.4%), nalidixic acid (1.6%), neomycin (0.6%), streptomycin (4.4%), sulfamethoxazole (4.2%), tetracycline (4.0%) and trimethoprim (1.4%), whereas all isolates were susceptible to co-amoxiclav, ceftiofur, ciprofloxacin, colistin...... and gentamicin. All nine ampicillin-resistant isolates contained a sequence similar to the bla(TEM-1b) gene, one of the eight chloramphenicol-resistant isolates a sequence similar to the catA1 gene, all three neomycin-resistant isolates a sequence similar to the aphA-2 gene, 16 (73%) of the 22 streptomycin...

  6. Antimicrobial Resistance in the Food Chain: A Review

    Directory of Open Access Journals (Sweden)

    Lieve Herman

    2013-06-01

    Full Text Available Antimicrobial resistant zoonotic pathogens present on food constitute a direct risk to public health. Antimicrobial resistance genes in commensal or pathogenic strains form an indirect risk to public health, as they increase the gene pool from which pathogenic bacteria can pick up resistance traits. Food can be contaminated with antimicrobial resistant bacteria and/or antimicrobial resistance genes in several ways. A first way is the presence of antibiotic resistant bacteria on food selected by the use of antibiotics during agricultural production. A second route is the possible presence of resistance genes in bacteria that are intentionally added during the processing of food (starter cultures, probiotics, bioconserving microorganisms and bacteriophages. A last way is through cross-contamination with antimicrobial resistant bacteria during food processing. Raw food products can be consumed without having undergone prior processing or preservation and therefore hold a substantial risk for transfer of antimicrobial resistance to humans, as the eventually present resistant bacteria are not killed. As a consequence, transfer of antimicrobial resistance genes between bacteria after ingestion by humans may occur. Under minimal processing or preservation treatment conditions, sublethally damaged or stressed cells can be maintained in the food, inducing antimicrobial resistance build-up and enhancing the risk of resistance transfer. Food processes that kill bacteria in food products, decrease the risk of transmission of antimicrobial resistance.

  7. Antimicrobial Resistance in the Food Chain: A Review

    Science.gov (United States)

    Verraes, Claire; Van Boxstael, Sigrid; Van Meervenne, Eva; Van Coillie, Els; Butaye, Patrick; Catry, Boudewijn; de Schaetzen, Marie-Athénaïs; Van Huffel, Xavier; Imberechts, Hein; Dierick, Katelijne; Daube, George; Saegerman, Claude; De Block, Jan; Dewulf, Jeroen; Herman, Lieve

    2013-01-01

    Antimicrobial resistant zoonotic pathogens present on food constitute a direct risk to public health. Antimicrobial resistance genes in commensal or pathogenic strains form an indirect risk to public health, as they increase the gene pool from which pathogenic bacteria can pick up resistance traits. Food can be contaminated with antimicrobial resistant bacteria and/or antimicrobial resistance genes in several ways. A first way is the presence of antibiotic resistant bacteria on food selected by the use of antibiotics during agricultural production. A second route is the possible presence of resistance genes in bacteria that are intentionally added during the processing of food (starter cultures, probiotics, bioconserving microorganisms and bacteriophages). A last way is through cross-contamination with antimicrobial resistant bacteria during food processing. Raw food products can be consumed without having undergone prior processing or preservation and therefore hold a substantial risk for transfer of antimicrobial resistance to humans, as the eventually present resistant bacteria are not killed. As a consequence, transfer of antimicrobial resistance genes between bacteria after ingestion by humans may occur. Under minimal processing or preservation treatment conditions, sublethally damaged or stressed cells can be maintained in the food, inducing antimicrobial resistance build-up and enhancing the risk of resistance transfer. Food processes that kill bacteria in food products, decrease the risk of transmission of antimicrobial resistance. PMID:23812024

  8. Antimicrobial resistance in the food chain: a review.

    Science.gov (United States)

    Verraes, Claire; Van Boxstael, Sigrid; Van Meervenne, Eva; Van Coillie, Els; Butaye, Patrick; Catry, Boudewijn; de Schaetzen, Marie-Athénaïs; Van Huffel, Xavier; Imberechts, Hein; Dierick, Katelijne; Daube, George; Saegerman, Claude; De Block, Jan; Dewulf, Jeroen; Herman, Lieve

    2013-06-28

    Antimicrobial resistant zoonotic pathogens present on food constitute a direct risk to public health. Antimicrobial resistance genes in commensal or pathogenic strains form an indirect risk to public health, as they increase the gene pool from which pathogenic bacteria can pick up resistance traits. Food can be contaminated with antimicrobial resistant bacteria and/or antimicrobial resistance genes in several ways. A first way is the presence of antibiotic resistant bacteria on food selected by the use of antibiotics during agricultural production. A second route is the possible presence of resistance genes in bacteria that are intentionally added during the processing of food (starter cultures, probiotics, bioconserving microorganisms and bacteriophages). A last way is through cross-contamination with antimicrobial resistant bacteria during food processing. Raw food products can be consumed without having undergone prior processing or preservation and therefore hold a substantial risk for transfer of antimicrobial resistance to humans, as the eventually present resistant bacteria are not killed. As a consequence, transfer of antimicrobial resistance genes between bacteria after ingestion by humans may occur. Under minimal processing or preservation treatment conditions, sublethally damaged or stressed cells can be maintained in the food, inducing antimicrobial resistance build-up and enhancing the risk of resistance transfer. Food processes that kill bacteria in food products, decrease the risk of transmission of antimicrobial resistance.

  9. How to fight antimicrobial resistance.

    Science.gov (United States)

    Foucault, Cédric; Brouqui, Philippe

    2007-03-01

    Antimicrobial misuse results in the development of resistance and superbugs. Over recent decades, resistance has been increasing despite continuing efforts to control it, resulting in increased mortality and cost. Many authorities have proposed local, regional and national guidelines to fight against this phenomenon, and the usefulness of these programmes has been evaluated. Multifaceted intervention seems to be the most efficient method to control antimicrobial resistance. Monitoring of bacterial resistance and antibiotic use is essential, and the methodology has now been homogenized. The implementation of guidelines and infection control measures does not control antimicrobial resistance and needs to be reinforced by associated measures. Educational programmes and rotation policies have not been evaluated sufficiently in the literature. Combination antimicrobial therapy is inefficient in controlling antimicrobial resistance.

  10. Analysis of Antimicrobial Resistance Genes in Multiple Drug Resistant (MDR) Salmonella enterica Isolated from Animals and Humans

    Science.gov (United States)

    Background: Multiple Drug Resistant (MDR) foodborne bacteria are a concern in animal and human health. Identification of resistance genes in foodborne pathogens is necessary to determine similarities of resistance mechanisms in animal, food and human clinical isolates. This information will help us ...

  11. Benchmarking of methods for identification of antimicrobial resistance genes in bacterial whole genome data

    DEFF Research Database (Denmark)

    Clausen, Philip T. L. C.; Zankari, Ea; Aarestrup, Frank Møller;

    2016-01-01

    was compared with the observed phenotypes for all isolates. To challenge further the sensitivity of the in silico methods, the datasets were also down-sampled to 1% of the reads and reanalysed. The best results were obtained by identification of resistance genes by mapping directly against the raw reads......Next generation sequencing (NGS) may be an alternative to phenotypic susceptibility testing for surveillance and clinical diagnosis. However, current bioinformatics methods may be associated with false positives and negatives. In this study, a novel mapping method was developed and benchmarked...... to two different methods in current use for identification of antibiotic resistance genes in bacterial WGS data. A novel method, KmerResistance, which examines the co-occurrence of k-mers between the WGS data and a database of resistance genes, was developed. The performance of this method was compared...

  12. [Enhanced resistance to phytopathogenic bacteria in transgenic tobacco plants with synthetic gene of antimicrobial peptide cecropin P1].

    Science.gov (United States)

    Zakharchenko, N S; Rukavtsova, E B; Gudkov, A T; Bur'ianov, Ia I

    2005-11-01

    Plasmids with a synthetic gene of the mammalian antimicrobial peptide cecropin P1 (cecP1) controlled by the constitutive promoter 35S RNA of cauliflower mosaic virus were constructed. Agrobacterial transformation of tobacco plants was conducted using the obtained recombinant binary vector. The presence of gene cecP1 in the plant genome was confirmed by PCR. The expression of gene cecP1 in transgenic plants was shown by Northern blot analysis. The obtained transgenic plants exhibit enhanced resistance to phytopathogenic bacteria Pseudomonas syringae, P. marginata, and Erwinia carotovora. The ability of transgenic plants to express cecropin P1 was transmitted to the progeny. F1 and F2 plants had the normal phenotype (except for a changed coloration of flowers) and retained the ability to produce normal viable seeds upon self-pollination. Lines of F1 plants with Mendelian segregation of transgenic traits were selected.

  13. Pathogen-induced expression of a cecropin A-melittin antimicrobial peptide gene confers antifungal resistance in transgenic tobacco.

    Science.gov (United States)

    Yevtushenko, Dmytro P; Romero, Rafael; Forward, Benjamin S; Hancock, Robert E; Kay, William W; Misra, Santosh

    2005-06-01

    Expression of defensive genes from a promoter that is specifically activated in response to pathogen invasion is highly desirable for engineering disease-resistant plants. A plant transformation vector was constructed with transcriptional fusion between the pathogen-responsive win3.12T promoter from poplar and the gene encoding the novel cecropin A-melittin hybrid peptide (CEMA) with strong antimicrobial activity. This promoter-transgene combination was evaluated in transgenic tobacco (Nicotiana tabacum L. cv. Xanthi) for enhanced plant resistance against a highly virulent pathogenic fungus Fusarium solani. Transgene expression in leaves was strongly increased after fungal infection or mechanical wounding, and the accumulation of CEMA transcripts was found to be systemic and positively correlated with the number of transgene insertions. A simple and efficient in vitro regeneration bioassay for preliminary screening of transgenic lines against pathogenic fungi was developed. CEMA had strong antifungal activity in vitro, inhibiting conidia germination at concentrations that were non-toxic to tobacco protoplasts. Most importantly, the expression level of the CEMA peptide in vivo, regulated by the win3.12T promoter, was sufficient to confer resistance against F. solani in transgenic tobacco. The antifungal resistance of plants with high CEMA expression was strong and reproducible. In addition, leaf tissue extracts from transgenic plants significantly reduced the number of fungal colonies arising from germinated conidia. Accumulation of CEMA peptide in transgenic tobacco had no deleterious effect on plant growth and development. This is the first report showing the application of a heterologous pathogen-inducible promoter to direct the expression of an antimicrobial peptide in plants, and the feasibility of this approach to provide disease resistance in tobacco and, possibly, other crops. PMID:15863447

  14. Antimicrobial resistance in bacteria from horses: Epidemiology of antimicrobial resistance.

    Science.gov (United States)

    Maddox, T W; Clegg, P D; Williams, N J; Pinchbeck, G L

    2015-11-01

    Antimicrobial resistance poses a significant threat to the continued successful use of antimicrobial agents for the treatment of bacterial infections. While the epidemiology of antimicrobial resistance in bacteria from man has been studied extensively, less work has been undertaken in companion animals, particularly horses. Methicillin-resistant Staphylococcus aureus has been identified as a cause of infections, with a low prevalence of nasal carriage by horses in the community but higher for hospitalised horses. Molecular characterisation has shown methicillin-resistant Staphylococcus aureus strains either to be predominantly of types associated with horses or of sequence type ST398. Antimicrobial-resistant Escherichia coli (including multidrug-resistant and extended spectrum β-lactamase-producing isolates) have caused infections and been documented in faecal carriage by horses, with many significant resistance mechanisms identified. More sporadic reports and molecular characterisation exist for resistance in other bacteria such as enterococci, Salmonella, Acinetobacter and Pseudomonas species. Limited work has been undertaken evaluating risk factors and much of the epidemiology of antimicrobial resistance in bacteria from horses remains to be determined.

  15. Antimicrobial resistance in bacteria from horses: Epidemiology of antimicrobial resistance.

    Science.gov (United States)

    Maddox, T W; Clegg, P D; Williams, N J; Pinchbeck, G L

    2015-11-01

    Antimicrobial resistance poses a significant threat to the continued successful use of antimicrobial agents for the treatment of bacterial infections. While the epidemiology of antimicrobial resistance in bacteria from man has been studied extensively, less work has been undertaken in companion animals, particularly horses. Methicillin-resistant Staphylococcus aureus has been identified as a cause of infections, with a low prevalence of nasal carriage by horses in the community but higher for hospitalised horses. Molecular characterisation has shown methicillin-resistant Staphylococcus aureus strains either to be predominantly of types associated with horses or of sequence type ST398. Antimicrobial-resistant Escherichia coli (including multidrug-resistant and extended spectrum β-lactamase-producing isolates) have caused infections and been documented in faecal carriage by horses, with many significant resistance mechanisms identified. More sporadic reports and molecular characterisation exist for resistance in other bacteria such as enterococci, Salmonella, Acinetobacter and Pseudomonas species. Limited work has been undertaken evaluating risk factors and much of the epidemiology of antimicrobial resistance in bacteria from horses remains to be determined. PMID:26084443

  16. Antimicrobial susceptibility and macrolide resistance genes in Streptococcus pyogenes collected in Austria and Hungary.

    Science.gov (United States)

    Gattringer, Rainer; Sauermann, Robert; Lagler, Heimo; Stich, Karin; Buxbaum, Astrid; Graninger, Wolfgang; Georgopoulos, Apostolos

    2004-09-01

    A total of 341 clinical isolates of Streptococcus pyogenes from Vienna, Austria and three Hungarian cities were tested for susceptibility to four macrolides and 12 other antibiotics. All isolates were fully susceptible to penicillin and the other beta-lactams tested. A high level of tetracycline resistance was found in Austria (26.7%) and in Hungary (30.5%). The rate of resistance to erythromycin, clarithromycin and azithromycin was 4.7% in Vienna and 3.7% in the Hungarian communities. In both countries, the MIC(90) values of erythromycin and clarithromycin were 0.12 mg/L and the MIC(90) of josamycin was 0.5mg/L. The M phenotype of resistance conferred by the mefA genes was predominant (n = 9) among the macrolide-resistant isolates (n = 14).

  17. Antimicrobial resistance and virulence-associated genes of Salmonella enterica subsp. enterica serotypes Muenster, Florian, Omuna, and Noya strains isolated from clinically diarrheic humans in Egypt.

    Science.gov (United States)

    Osman, Kamelia M; Marouf, Sherif H; Alatfeehy, Nayerah

    2013-10-01

    Four serotypes recovered from clinically diarrheic human faecal samples (Salmonella Muenster, Salmonella Florian, Salmonella Omuna and Salmonella Noya) were investigated for the presence of 11 virulence genes (invA, avrA, ssaQ, mgtC, siiD, sopB, gipA, sodC1, sopE1, spvC, and bcfC) and their association with antibiotic resistance. The 4 Salmonella serotypes lacked virulence genes gipA and spvC. Resistance to 7 of the 14 antimicrobials was detected. The frequency of resistance, to lincomycin and streptomycin (100% of the Salmonella Muenster [2/5], Salmonella Florian [1/5], Salmonella Omuna [1/5], and Salmonella Noya [1/5] isolates), chloramphenicol (100% of the Salmonella Muenster [2/5] and Salmonella Florian [1/5] isolates) and trimethoprim-sulfamethoxazole (100% of the Salmonella Florian [1/5] and Salmonella Omuna [1/5] isolates) was an outstanding feature. With the rest of the antibiotics, the four Salmonella serotypes exhibited a great diversity in their resistance patterns. Overall, the four Salmonella serotypes were resistant to more than one antimicrobial. The antimicrobials to which the Salmonella Muenster, Salmonella Florian, and Salmonella Omuna isolates were resistant, contributed to five different antimicrobial resistance profiles. The virulence associated genes invA, ssaQ, siiD, sopB, and bcfC genes were 100% associated with certain antimicrobial resistance phenotypes (streptomycin and lincosamide) not recorded previously, and secondly, the presence of invA, avrA, ssaQ, mgtC, siiD, sopB, and bcfC was associated with resistance to chloramphenicol. The results of this study will help in understanding the spread of virulence genotypes and antibiotic resistance in Salmonella in the region of study.

  18. Engineering Antimicrobials Refractory to Resistance

    Science.gov (United States)

    Multi-drug resistant superbugs are a persistent problem in modern health care, demonstrating the need for a new class of antimicrobials that can address this concern. Triple-acting peptidoglycan hydrolase fusions are a novel class of antimicrobials which have qualities well suited to avoiding resis...

  19. Heterogeneity among Virulence and Antimicrobial Resistance Gene Profiles of Extraintestinal Escherichia coli Isolates of Animal and Human Origin

    OpenAIRE

    Maynard, Christine; Bekal, Sadjia; Sanschagrin, François; Levesque, Roger C.; Brousseau, Roland; Masson, Luke; Larivière, Serge; Harel, Josée

    2004-01-01

    Extraintestinal pathogenic Escherichia coli (ExPEC) isolates collected from different infected animals and from human patients with extraintestinal infections in 2001 were characterized for their phenotypic and genotypic antimicrobial resistance profiles, genotypes, and key virulence factors. Among the 10 antimicrobial agents tested, resistance to ampicillin, tetracycline, and sulfonamides was most frequent. Multiresistant strains were found in both the animal and the human groups of isolates...

  20. Virulence Genes and Antimicrobial Resistance Profiles of Pasteurella multocida Strains Isolated from Rabbits in Brazil

    Directory of Open Access Journals (Sweden)

    Thais Sebastiana Porfida Ferreira

    2012-01-01

    Full Text Available Pasteurella multocida is responsible for a wide range of diseases in domestic animals. In rabbits, the agent is related to nasal discharge, pneumonia, otitis media, pyometra, orchitis, abscess, and septicemia. One hundred and forty rabbits with respiratory diseases from four rabbitries in São Paulo State, Brazil were evaluated for the detection of P. multocida in their nasal cavities. A total of twenty-nine animals were positive to P. multocida isolation, and 46 strains were selected and characterized by means of biochemical tests and PCR. P. multocida strains were tested for capsular type, virulence genes, and resistance profile. A total of 45.6% (21/46 of isolates belonged to capsular type A, and 54.34% (25/46 of the isolates were untypeable. None of the strains harboured toxA or pfhA genes. The frequency of the other twenty genes tested was variable, and the data generated was used to build a dendrogram, showing the relatedness of strains, which were clustered according to origin. Resistance revealed to be more common against sulfonamides and cotrimoxazole, followed by erythromycin, penicillin, and amoxicillin.

  1. Antimicrobial resistance and virulence gene profiles in P. multocida strains isolated from cats

    Directory of Open Access Journals (Sweden)

    Thais Sebastiana Porfida Ferreira

    2015-03-01

    Full Text Available Cats are often described as carriers of Pasteurella multocida in their oral microbiota. This agent is thought to cause pneumonia, conjunctivitis, rhinitis, gingivostomatitis, abscess and osteonecrosis in cats. Human infection with P. multocida has been described in several cases affecting cat owners or after cat bites. In Brazil, the cat population is approximately 21 million animals and is increasing, but there are no studies of the presence of P. multocida in the feline population or of human cases of infection associated with cats. In this study, one hundred and ninety-one healthy cats from owners and shelters in São Paulo State, Brazil, were evaluated for the presence of P. multocida in their oral cavities. Twenty animals were positive for P. multocida, and forty-one strains were selected and characterized by means of biochemical tests and PCR. The P. multocida strains were tested for capsular type, virulence genes and resistance profile. A total of 75.6% (31/41 of isolates belonged to capsular type A, and 24.4% (10/41 of the isolates were untypeable. None of the strains harboured toxA, tbpA or pfhA genes. The frequencies of the other genes tested were variable, and the data generated were used to build a dendrogram showing the relatedness of strains, which were clustered according to origin. The most common resistance profile observed was against sulfizoxazole and trimethoprim-sulphamethoxazole.

  2. Severe sepsis facilitates intestinal colonization by extended-spectrum-β-lactamase-producing Klebsiella pneumoniae and transfer of the SHV-18 resistance gene to Escherichia coli during antimicrobial treatment.

    Science.gov (United States)

    Guan, Jun; Liu, Shaoze; Lin, Zhaofen; Li, Wenfang; Liu, Xuefeng; Chen, Dechang

    2014-01-01

    Infections caused by multidrug-resistant pathogens are frequent and life threatening in critically ill patients. To investigate whether severe sepsis affects gut colonization by resistant pathogens and genetic exchange between opportunistic pathogens, we tested the intestinal-colonization ability of an extended-spectrum beta-lactamase-producing Klebsiella pneumoniae strain carrying the SHV-18 resistance gene and the transfer ability of the resistance gene to endogenous Escherichia coli under ceftriaxone treatment in rats with burn injury only or severe sepsis induced by burns plus endotoxin exposure. Without ceftriaxone treatment, the K. pneumoniae strain colonized the intestine in both septic and burned rats for a short time, with clearance occurring earlier in burn-only rats but never in sham burn rats. In both burned and septic rats, the colonization level of the challenge strain dropped at the beginning and then later increased during ceftriaxone treatment, after which it declined gradually. This pattern coincided with the change in resistance of K. pneumoniae to ceftriaxone during and after ceftriaxone treatment. Compared with burn-only injury, severe sepsis had a more significant effect on the change in antimicrobial resistance to ceftriaxone. Only in septic rats was the resistance gene successfully transferred from the challenge strain to endogenous E. coli during ceftriaxone treatment; the gene persisted for at least 4 weeks after ceftriaxone treatment. We concluded that severe sepsis can facilitate intestinal colonization by an exogenous resistant pathogen and the transfer of the resistance gene to a potential endogenous pathogen during antimicrobial treatment. PMID:24277046

  3. Prevalence of enterotoxin-encoding genes and antimicrobial resistance in coagulase-negative and coagulase-positive Staphylococcus isolates from black pudding

    Directory of Open Access Journals (Sweden)

    Tiane Martin de Moura

    2012-10-01

    Full Text Available INTRODUCTION: Staphylococcal species are pathogens that are responsible for outbreaks of foodborne diseases. The aim of this study was to investigate the prevalence of enterotoxin-genes and the antimicrobial resistance profile in staphylococcus coagulase-negative (CoNS and coagulasepositive (CoPS isolates from black pudding in southern Brazil. METHODS: Two hundred typical and atypical colonies from Baird-Parker agar were inoculated on mannitol salt agar. Eighty-two mannitol-positive staphylococci were submitted to conventional biochemical tests and antimicrobial susceptibility profiling. The presence of coagulase (coa and enterotoxin (se genes was investigated by polymerase chain reaction. RESULTS: The isolates were divided into 2 groups: 75.6% (62/82 were CoNS and 24.4% (20/82 were CoPS. The biochemical tests identified 9 species, of which Staphylococcus saprophyticus (37.8% and Staphylococcus carnosus (15.9% were the most prevalent. Antimicrobial susceptibility tests showed resistance phenotypes to antibiotics widely administered in humans, such as gentamicin, tetracycline, chloramphenicol, and erythromycin. The coa gene was detected in 19.5% (16/82 of the strains and 4 polymorphic DNA fragments were observed. Five CoNS isolates carrying the coa gene were submitted for 16S rRNA sequencing and 3 showed similarity with CoNS. Forty strains were positive for at least 1 enterotoxin-encoding gene, the genes most frequently detected were sea (28.6% and seb (27.5%. CONCLUSIONS: The presence of antimicrobial resistant and enterotoxin-encoding genes in staphylococci isolates from black pudding indicated that this fermented food may represent a potential health risk, since staphylococci present in food could cause foodborne diseases or be a possible route for the transfer of antimicrobial resistance to humans.

  4. Characterization of Virulence-Associated Genes, Antimicrobial Resistance Genes, and Class 1 Integrons in Salmonella enterica serovar Typhimurium Isolates from Chicken Meat and Humans in Egypt.

    Science.gov (United States)

    Ahmed, Heba A; El-Hofy, Fatma I; Shafik, Saleh M; Abdelrahman, Mahmoud A; Elsaid, Gamilat A

    2016-06-01

    Foodborne pathogens are leading causes of illness especially in developing countries. The current study aimed to characterize virulence-associated genes and antimicrobial resistance in 30 Salmonella Typhimurium isolates of chicken and human origin at Mansoura, Egypt. The results showed that invA, avrA, mgtC, stn, and bcfC genes were identified in all the examined isolates, while 96.7% and 6.7% were positive for sopB and pef genes, respectively. The highest resistance frequencies of the isolates were to chloramphenicol and trimethoprim-sulfamethoxazole (73.3%, each), followed by streptomycin (56.7%), tetracycline and ampicillin (53.3%, each), and gentamicin (30%). However, only 2.7% of the isolates were resistant to cefotaxime and ceftriaxone each. Different resistance-associated genes, including blaTEM, aadB, aadC, aadA1, aadA2, floR, tetA(A), tetA(B), and sul1, were identified in Salmonella Typhimurium isolates with the respective frequencies of 53.3%, 6.7%, 23.3%, 46.7%, 63.3%, 73.3%, 60%, 20%, and 96.7%. None of the isolates was positive for blaSHV, blaOXA, and blaCMY genes. The results showed that the intI1 gene was detected in 24 (80%) of the examined Salmonella Typhimurium isolates. Class 1 integrons were found in 19 (79.2%) isolates that were intI1 positive. Seven integron profiles (namely: P-I to P-VII) were identified with P-V (gene cassette dfrA15, aadA2), the most prevalent profile. To the best of our knowledge, this is the first study to characterize the unusual gene cassette array dfrA12-OrfF-aadA27 from Salmonella Typhimurium isolates in Egypt. PMID:26977940

  5. Antimicrobial resistance and resistance genes of pathogenic Salmonella recently isolated from chicken%鸡源致病性沙门氏菌新近分离株的耐药性与耐药基因

    Institute of Scientific and Technical Information of China (English)

    廖成水; 程相朝; 张春杰; 李银聚; 吴庭才; 李小康; 王晓利; 胡阿勇

    2011-01-01

    The aim of this study was to study antimicrobial susceptibility and resistance gene of the clinical isolates of Salmonella recently isolated from chicken and to provide materials for further studies on the molecular mechanisms of bacterial resistance and development of the new antimicrobial agents.The isolates were evaluated for antimicrobial sensitivity by K-B disc diffusion method against 22 antimicrobial drugs.Then,13 resistance genes of the isolates were detected by PCR.All isolates were resistance to erythromycin and penicillin,among them resistance to azithromycin and ampicillin was found from 60% to 70%,but susceptible to polymyxin B,amikacin,gentamicin and nalidixic acid.96.94% of the isolates were resis-tant to 3 or more antimicrobial agents,56.12% of them were resistant to 7 or more antimicrobial agents and 2 isolates were resistant to 18 of the 22 antimicrobial agents.A total of 11 different antimicrobial resistance genes were amplified.The above results showed that Salmonella was easy to form the resistance to drug,and resistance genes were widely existed in these resistant strains,but there was no correlation between resistant phenotype and resistance genes.%为了了解河南省鸡源沙门氏菌新近分离株的药物敏感性和耐药基因的存在情况,为进一步研究细菌耐药的分子机制和新型抗菌药物的研制提供资料,利用K-B法检测了98株鸡源沙门氏菌对22种药物的敏感性,采用PCR方法检测了13种常见耐药基因在分离株中的分布情况。结果显示,所有菌株对红霉素、青霉素、阿齐霉素和氨苄西林的耐药率均在60%~100%之间。三重以上耐药的菌株高达96.94%,七重以上耐药的菌株为56.12%,耐药最多的菌株可耐受18种抗生素。从13种常见耐药基因中扩增到3种四环素类、2种氨基糖苷类、2种β-内酰

  6. Trends in antimicrobial susceptibility in relation to antimicrobial usage and presence of resistance genes in Staphylococcus hyicus isolated from exudative epidermitis in pigs

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Jensen, Lars Bogø

    2002-01-01

    From 1996 to 2001 a total of 467 Staphylococcus hyicus isolates from exudative epidermitis (EE) in pigs in Denmark were examined for susceptibility to 13 different antimicrobial agents. The presence of selected genes encoding macrolide (erm(A), erm(B) and erm(C)), penicillin (blaZ), streptogramin...

  7. Development of a miniaturised microarray-based assay for the rapid identification of antimicrobial resistance genes in Gram-negative bacteria

    DEFF Research Database (Denmark)

    Batchelor, Miranda; Hopkins, Katie L; Liebana, Ernesto;

    2008-01-01

    We describe the development of a miniaturised microarray for the detection of antimicrobial resistance genes in Gram-negative bacteria. Included on the array are genes encoding resistance to aminoglycosides, trimethoprim, sulphonamides, tetracyclines and beta-lactams, including extended......-spectrum beta-lactamases. Validation of the array with control strains demonstrated a 99% correlation between polymerase chain reaction and array results. There was also good correlation between phenotypic and genotypic results for a large panel of Escherichia coli and Salmonella isolates. Some differences were...... also seen in the number and type of resistance genes harboured by E. coli and Salmonella strains. The array provides an effective, fast and simple method for detection of resistance genes in clinical isolates suitable for use in diagnostic laboratories, which in future will help to understand...

  8. Occurrence of integrons and antimicrobial resistance genes among Salmonella enterica from Brazil

    DEFF Research Database (Denmark)

    Peirano, G.; Agersø, Yvonne; Aarestrup, Frank Møller;

    2006-01-01

    . The genetic location of class 1 integrons was determined in 25 isolates by hybridization and plasmid transfer experiments. Results: Fifty-five of the isolates were positive for class I integrons. Integron-positive isolates represented 17 different serovars and were mainly from human (n = 28) and animal (n...... resistance was primarily mediated by sul2 and sul3, tetracycline resistance by tet(B) and tet(A), chloramphenicol resistance by catA1, streptomycin resistance by strA and ampicillin resistance by bla(TEM). bla(CTX) and bla(CMY-2) were found in cephalosporin-resistant isolates. Mating and hybridization...

  9. Antibiotic / Antimicrobial Resistance Glossary

    Science.gov (United States)

    ... Recommendations Pediatric Treatment Recommendations Inpatient Healthcare Professionals Community Pharmacists Continuing Education & Curriculum Opportunities Weighing in on Antibiotic Resistance Improving Prescribing Outpatient Antibiotic Stewardship Interventions That Work Systematic Reviews ...

  10. Trends in antimicrobial susceptibility and presence of resistance genes in Staphylococcus hyicus isolated from exudative epidermitis in pigs

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Jensen, L. B.

    2002-01-01

    From 1996 to 2001 a total of 467 Staphylococcus hyicus isolates from exudative epidermitis (EE) in pigs in Denmark were examined for susceptibility to 13 different antimicrobial agents. The presence of selected genes encoding macrolide (erm(A), erm(B) and erm(C)), penicillin (blaZ), streptogramin...

  11. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... resistance more real and understandable to veterinarians, livestock producers, lawmakers, consumer representatives and other key audiences. We ... Regulatory Information Safety Emergency Preparedness International Programs News & ... Training & Continuing Education Inspections & Compliance Federal, State & Local ...

  12. Antimicrobial (Drug) Resistance: Gonorrhea

    Science.gov (United States)

    ... Marketing Share this: Main Content Area Multidrug-Resistant Neisseria gonorrhoeae (Gonorrhea) During the past 50 years, the use ... Gonorrhea is a sexually transmitted disease caused by Neisseria gonorrhoeae , a bacterium that can infect areas of the ...

  13. Salmon aquaculture and antimicrobial resistance in the marine environment.

    Science.gov (United States)

    Buschmann, Alejandro H; Tomova, Alexandra; López, Alejandra; Maldonado, Miguel A; Henríquez, Luis A; Ivanova, Larisa; Moy, Fred; Godfrey, Henry P; Cabello, Felipe C

    2012-01-01

    Antimicrobials used in salmon aquaculture pass into the marine environment. This could have negative impacts on marine environmental biodiversity, and on terrestrial animal and human health as a result of selection for bacteria containing antimicrobial resistance genes. We therefore measured the numbers of culturable bacteria and antimicrobial-resistant bacteria in marine sediments in the Calbuco Archipelago, Chile, over 12-month period at a salmon aquaculture site approximately 20 m from a salmon farm and at a control site 8 km distant without observable aquaculture activities. Three antimicrobials extensively used in Chilean salmon aquaculture (oxytetracycline, oxolinic acid, and florfenicol) were studied. Although none of these antimicrobials was detected in sediments from either site, traces of flumequine, a fluoroquinolone antimicrobial also widely used in Chile, were present in sediments from both sites during this period. There were significant increases in bacterial numbers and antimicrobial-resistant fractions to oxytetracycline, oxolinic acid, and florfenicol in sediments from the aquaculture site compared to those from the control site. Interestingly, there were similar numbers of presumably plasmid-mediated resistance genes for oxytetracycline, oxolinic acid and florfenicol in unselected marine bacteria isolated from both aquaculture and control sites. These preliminary findings in one location may suggest that the current use of large amounts of antimicrobials in Chilean aquaculture has the potential to select for antimicrobial-resistant bacteria in marine sediments.

  14. Antimicrobial resistance in Dschang, Cameroon

    Directory of Open Access Journals (Sweden)

    Fusi-Ngwa Catherine Kesah

    2013-01-01

    Full Text Available Background: Health-care-associated and community infections remain problematic in most of Africa where the increasing incidences of diseases, wars, poverty, malnutrition, and general environmental deterioration have led to the gradual collapse of the health-care system. Detection of antimicrobial resistance (AMR remains imperative for the surveillance purposes and optimal management of infectious diseases. This study reports the status of AMR in pathogens in Dschang. Materials and Methods: From May 2009 to March 2010, the clinical specimens collected at two hospitals were processed accorded to the standard procedures. Antibiotic testing was performed by E test, and antimycotics by disc-agar diffusion, as recommended by the Clinical and Laboratory Standards Institute on pathogens comprising Staphylococcus aureus (100 strains, Enterococcus faecalis (35, Klebsiella pneumoniae (75, Escherichia coli (50, Proteus mirabilis (30, Pseudomonas aruginosa (50, Acinetobacter species (20, and Candida albicans (150 against common antimicrobials. Results: There was no vancomycin resistance in the cocci, the minimum inhibitory concentration for 90% of these strains MIC 90 was 3 μg/ml, methicillin-resistant S. aureus (MRSA was 43%, benzyl penicillin 89% resistance in S. aureus as opposed to 5.7% in E. faecalis. Low resistance (<10% was recorded to cefoxitin, cefotaxime, and nalidixic acid (MIC 90 3-8 μg/ml against the coliforms, and to ticarcillin, aztreonam, imipenem, gentamicin, and ciprofloxacin among the non-enterobacteria; tetracycline, amoxicillin, piperacillin, and chloramphenicol were generally ineffective. Resistance rates to fluconazole, clotrimazole, econazole, and miconazole were <55% against C. albicans. The pathogens tested exhibited multidrug-resistance. Conclusion: The present findings were intended to support antimicrobial stewardship endeavors and empiric therapy. The past, present, and the future investigations in drug efficacy will continue

  15. Antimicrobial resistance and virulence factor gene profiles of Enterococcus spp. isolates from wild Arctocephalus australis (South American fur seal) and Arctocephalus tropicalis (Subantarctic fur seal).

    Science.gov (United States)

    Santestevan, Naiara Aguiar; de Angelis Zvoboda, Dejoara; Prichula, Janira; Pereira, Rebeca Inhoque; Wachholz, Guilherme Raffo; Cardoso, Leonardo Almansa; de Moura, Tiane Martin; Medeiros, Aline Weber; de Amorin, Derek Blaese; Tavares, Maurício; d'Azevedo, Pedro Alves; Franco, Ana Claudia; Frazzon, Jeverson; Frazzon, Ana Paula Guedes

    2015-12-01

    Enterococci are natural inhabitants of the gastrointestinal tracts in humans and animals. Epidemiological data suggest that enterococci are important reservoirs of antimicrobial resistant genes that may be transmitted from other bacterial species The aim of this study was to investigate the species composition, antimicrobial resistance and virulence genes in enterococci recovered from fecal samples of wild Arctocephalus australis and A. tropicalis found dead along the South Coast of Brazil. From a total of 43 wild fur seals, eleven were selected for this study. Phenotypic and genotypic characterizations were used to classify Enterococcus species. Strains were tested for susceptibility to 10 antibiotics, presence of ace, gelE, asa, cylA, tet(L), tet(M) and erm(B) genes by PCR, and genetic variability using RAPD-PCR. Among the 50 enterococci isolated, 40% were Enterococcus faecalis, 40% E. hirae, 12% E. casseliflavus and 8 % other enterococcal species. Resistance profiles were observed to erythromycin, nitrofurantoin, tetracycline, norfloxacin and ciprofloxacin. The prevalence of virulence genes was ace (68%), gelE (54%), asa (22%) and cylA (4%). In erythromycin- and tetracycline strains, erm(B) and tet(M) were detected, respectively. The RAPD-PCR demonstrated a close phylogenetic relationship between the enterococci isolated from A. australis and A. tropicalis. In conclusion, different enterococcus species showing antimicrobial resistance and virulence determinates were isolated from fecal samples of fur seals. Antibiotic resistant strains in these animals could be related within food chain and aquatic pollutants or linked to environmental resistome, and demonstrates the potential importance of these animals as reservoirs and disseminators of such determinants in marine environmental.

  16. Antimicrobial Resistance in the Environment.

    Science.gov (United States)

    Williams, Maggie R; Stedtfeld, Robert D; Guo, Xueping; Hashsham, Syed A

    2016-10-01

    This review summarizes important publications from 2015 pertaining to the occurrence of antimicrobial resistance (AMR) in the environment. Emphasis is placed on sources of antibiotic resistance in the aquatic environment including wastewater treatment plants, hospitals, and agriculture, treatment and mitigation techniques, and surveillance and analysis methodologies for characterizing abundance data. As such, this review is organized into the following sections: i) occurrence of AMR in the environment, including surface waters, aquaculture, and wastewater ii) treatment technologies, and iii) technologies for rapid surveillance of AMR, iv) transmission between matrices, v) databases and analysis methods, and vi) gaps in AMR understanding. PMID:27620115

  17. Comparison of two DNA microarrays for detection of plasmid-mediated antimicrobial resistance and virulence factor genes in clinical isolates of Enterobacteriaceae and non-Enterobacteriaceae.

    LENUS (Irish Health Repository)

    Walsh, Fiona

    2010-06-01

    A DNA microarray was developed to detect plasmid-mediated antimicrobial resistance (AR) and virulence factor (VF) genes in clinical isolates of Enterobacteriaceae and non-Enterobacteriaceae. The array was validated with the following bacterial species: Escherichiacoli (n=17); Klebsiellapneumoniae (n=3); Enterobacter spp. (n=6); Acinetobacter genospecies 3 (n=1); Acinetobacterbaumannii (n=1); Pseudomonasaeruginosa (n=2); and Stenotrophomonasmaltophilia (n=2). The AR gene profiles of these isolates were identified by polymerase chain reaction (PCR). The DNA microarray consisted of 155 and 133 AR and VF gene probes, respectively. Results were compared with the commercially available Identibac AMR-ve Array Tube. Hybridisation results indicated that there was excellent correlation between PCR and array results for AR and VF genes. Genes conferring resistance to each antibiotic class were identified by the DNA array. Unusual resistance genes were also identified, such as bla(SHV-5) in a bla(OXA-23)-positive carbapenem-resistant A. baumannii. The phylogenetic group of each E. coli isolate was verified by the array. These data demonstrate that it is possible to screen simultaneously for all important classes of mobile AR and VF genes in Enterobacteriaceae and non-Enterobacteriaceae whilst also assigning a correct phylogenetic group to E. coli isolates. Therefore, it is feasible to test clinical Gram-negative bacteria for all known AR genes and to provide important information regarding pathogenicity simultaneously.

  18. Distribution of Serotypes and Antimicrobial Resistance Genes among Streptococcus agalactiae Isolates from Bovine and Human Hosts

    OpenAIRE

    Dogan, Belgin; Schukken, Y. H.; de Santisteban, C.; Boor, Kathryn J.

    2005-01-01

    To better understand the emergence and transmission of antibiotic-resistant Streptococcus agalactiae, we compared phenotypic and genotypic characteristics of 52 human and 83 bovine S. agalactiae isolates. Serotypes found among isolates from human hosts included V (48.1%), III (19.2%), Ia and Ib (13.5% each), and II (5.8%). Among isolates from bovine hosts, molecular serotypes III and II were predominant (53 and 14.5%, respectively). Four and 21 different ribotypes were found among human and b...

  19. Fast DNA serotyping and antimicrobial resistance gene determination of salmonella enterica with an oligonucleotide microarray-based assay.

    Science.gov (United States)

    Braun, Sascha D; Ziegler, Albrecht; Methner, Ulrich; Slickers, Peter; Keiling, Silke; Monecke, Stefan; Ehricht, Ralf

    2012-01-01

    Salmonellosis caused by Salmonella (S.) belongs to the most prevalent food-borne zoonotic diseases throughout the world. Therefore, serotype identification for all culture-confirmed cases of Salmonella infection is important for epidemiological purposes. As a standard, the traditional culture method (ISO 6579:2002) is used to identify Salmonella. Classical serotyping takes 4-5 days to be completed, it is labor-intensive, expensive and more than 250 non-standardized sera are necessary to characterize more than 2,500 Salmonella serovars currently known. These technical difficulties could be overcome with modern molecular methods. We developed a microarray based serogenotyping assay for the most prevalent Salmonella serovars in Europe and North America. The current assay version could theoretically discriminate 28 O-antigens and 86 H-antigens. Additionally, we included 77 targets analyzing antimicrobial resistance genes. The Salmonella assay was evaluated with a set of 168 reference strains representing 132 serovars previously serotyped by conventional agglutination through various reference centers. 117 of 132 (81%) tested serovars showed an unique microarray pattern. 15 of 132 serovars generated a pattern which was shared by multiple serovars (e.g., S. ser. Enteritidis and S. ser. Nitra). These shared patterns mainly resulted from the high similarity of the genotypes of serogroup A and D1. Using patterns of the known reference strains, a database was build which represents the basis of a new PatternMatch software that can serotype unknown Salmonella isolates automatically. After assay verification, the Salmonella serogenotyping assay was used to identify a field panel of 105 Salmonella isolates. All were identified as Salmonella and 93 of 105 isolates (88.6%) were typed in full concordance with conventional serotyping. This microarray based assay is a powerful tool for serogenotyping. PMID:23056321

  20. Fast DNA serotyping and antimicrobial resistance gene determination of salmonella enterica with an oligonucleotide microarray-based assay.

    Directory of Open Access Journals (Sweden)

    Sascha D Braun

    Full Text Available Salmonellosis caused by Salmonella (S. belongs to the most prevalent food-borne zoonotic diseases throughout the world. Therefore, serotype identification for all culture-confirmed cases of Salmonella infection is important for epidemiological purposes. As a standard, the traditional culture method (ISO 6579:2002 is used to identify Salmonella. Classical serotyping takes 4-5 days to be completed, it is labor-intensive, expensive and more than 250 non-standardized sera are necessary to characterize more than 2,500 Salmonella serovars currently known. These technical difficulties could be overcome with modern molecular methods. We developed a microarray based serogenotyping assay for the most prevalent Salmonella serovars in Europe and North America. The current assay version could theoretically discriminate 28 O-antigens and 86 H-antigens. Additionally, we included 77 targets analyzing antimicrobial resistance genes. The Salmonella assay was evaluated with a set of 168 reference strains representing 132 serovars previously serotyped by conventional agglutination through various reference centers. 117 of 132 (81% tested serovars showed an unique microarray pattern. 15 of 132 serovars generated a pattern which was shared by multiple serovars (e.g., S. ser. Enteritidis and S. ser. Nitra. These shared patterns mainly resulted from the high similarity of the genotypes of serogroup A and D1. Using patterns of the known reference strains, a database was build which represents the basis of a new PatternMatch software that can serotype unknown Salmonella isolates automatically. After assay verification, the Salmonella serogenotyping assay was used to identify a field panel of 105 Salmonella isolates. All were identified as Salmonella and 93 of 105 isolates (88.6% were typed in full concordance with conventional serotyping. This microarray based assay is a powerful tool for serogenotyping.

  1. Relationships between antimicrobial resistance, distribution of virulence factor genes and the origin of Trueperella pyogenes isolated from domestic animals and European bison (Bison bonasus).

    Science.gov (United States)

    Rzewuska, Magdalena; Czopowicz, Michał; Gawryś, Marta; Markowska-Daniel, Iwona; Bielecki, Wojciech

    2016-07-01

    Trueperella pyogenes is an opportunistic pathogen causing suppurative infections in livestock and wild animals. Although this bacterium is known for a long time, our knowledge about its pathogenicity is still insufficient. In this study the relationships between antimicrobial resistance profiles, distribution of virulence factor genes and the origin of T. pyogenes isolates were investigated. Isolates (n = 97) from various infections in domestic animals and European bison were studied. Minimal inhibitory concentrations of 12 antimicrobials were determined by a strip diffusion method, and PCR was used for detection of genes encoding seven putative virulence factors. All strains were susceptible to tested beta-lactams, and a statistically significant correlation between the resistance to enrofloxacin, tetracycline, macrolides, clindamycin, and a strain origin was found. The isolates from European bison were more susceptible than those from livestock, however the resistance to tetracycline and fluoroquinolones was observed. The plo and fimA genes were detected in all strains. There was no statistically significant association between the distribution of particular virulence factor genes and the type of infection, but the nanH, nanP and fimG genes were less frequently found in the isolates from European bison. The presence of three genes, nanP, nanH and cbpA, was found to be related to the resistance to tetracycline and ciprofloxacin. In conclusion, the resistance patterns of T. pyogenes were correlated with an isolate origin, but our findings did not allow to indicate which of the putative virulence factors may play a crucial role in the pathogenesis of particular types of T. pyogenes infection.

  2. Antimicrobial susceptibility and antibiotic resistance gene transfer analysis of foodborne, clinical, and environmental Listeria spp. isolates including Listeria monocytogenes.

    Science.gov (United States)

    Bertsch, David; Muelli, Mirjam; Weller, Monika; Uruty, Anaïs; Lacroix, Christophe; Meile, Leo

    2014-02-01

    The aims of this study were to assess antibiotic resistance pheno- and genotypes in foodborne, clinical, and environmental Listeria isolates, as well as to elucidate the horizontal gene transfer potential of detected resistance genes. A small fraction of in total 524 Listeria spp. isolates (3.1%) displayed acquired antibiotic resistance mainly to tetracycline (n = 11), but also to clindamycin (n = 4) and trimethoprim (n = 3), which was genotypically confirmed. In two cases, a tetracycline resistance phenotype was observed together with a trimethoprim resistance phenotype, namely in a clinical L. monocytogenes strain and in a foodborne L. innocua isolate. Depending on the applied guidelines, a differing number of isolates (n = 2 or n = 20) showed values for ampicillin that are on the edge between intermediate susceptibility and resistance. Transferability of the antibiotic resistance genes from the Listeria donors, elucidated in vitro by filter matings, was demonstrated for genes located on transposons of the Tn916 family and for an unknown clindamycin resistance determinant. Transfer rates of up to 10(-5) transconjugants per donor were obtained with a L. monocytogenes recipient and up to 10(-7) with an Enterococcus faecalis recipient, respectively. Although the prevalence of acquired antibiotic resistance in Listeria isolates from this study was rather low, the transferability of these resistances enables further spread in the future. This endorses the importance of surveillance of L. monocytogenes and other Listeria spp. in terms of antibiotic susceptibility.

  3. Antimicrobial Resistance: Is the World UNprepared?

    Science.gov (United States)

    2016-09-01

    Long Blurb: On September 21st 2016 the United Nations General Assembly convenes in New York, United States to tackle a looming and seemingly inevitable global challenge with the potential to threaten the health and wellbeing of all people: antimicrobial resistance. In an Editorial, the PLOS Medicine Editors reflect on the challenge of coordinating the response to antimicrobial resistance in order to ensure the viability of current antimicrobials and the development of new therapies against resistant pathogens. Short Blurb: In this month's Editorial, the PLOS Medicine Editors reflect on the upcoming United Nations General Assembly meeting which convenes to discuss the global challenge of antimicrobial resistance. PMID:27618631

  4. High prevalence of multidrug-tolerant bacteria and associated antimicrobial resistance genes isolated from ornamental fish and their carriage water

    Science.gov (United States)

    Objectives: The aim of the study was to assess the extent to which ornamental fish and their carriage water harbour antibiotic resistant bacteria and associated antibiotic resistance genes. Methods: 129 Aeromonas spp. isolated from warm water and coldwater ornamental fish species were screened for r...

  5. Aquaculture as yet another environmental gateway to the development and globalisation of antimicrobial resistance.

    Science.gov (United States)

    Cabello, Felipe C; Godfrey, Henry P; Buschmann, Alejandro H; Dölz, Humberto J

    2016-07-01

    Aquaculture uses hundreds of tonnes of antimicrobials annually to prevent and treat bacterial infection. The passage of these antimicrobials into the aquatic environment selects for resistant bacteria and resistance genes and stimulates bacterial mutation, recombination, and horizontal gene transfer. The potential bridging of aquatic and human pathogen resistomes leads to emergence of new antimicrobial-resistant bacteria and global dissemination of them and their antimicrobial resistance genes into animal and human populations. Efforts to prevent antimicrobial overuse in aquaculture must include education of all stakeholders about its detrimental effects on the health of fish, human beings, and the aquatic ecosystem (the notion of One Health), and encouragement of environmentally friendly measures of disease prevention, including vaccines, probiotics, and bacteriophages. Adoption of these measures is a crucial supplement to efforts dealing with antimicrobial resistance by developing new therapeutic agents, if headway is to be made against the increasing problem of antimicrobial resistance in human and veterinary medicine. PMID:27083976

  6. Aquaculture as yet another environmental gateway to the development and globalisation of antimicrobial resistance.

    Science.gov (United States)

    Cabello, Felipe C; Godfrey, Henry P; Buschmann, Alejandro H; Dölz, Humberto J

    2016-07-01

    Aquaculture uses hundreds of tonnes of antimicrobials annually to prevent and treat bacterial infection. The passage of these antimicrobials into the aquatic environment selects for resistant bacteria and resistance genes and stimulates bacterial mutation, recombination, and horizontal gene transfer. The potential bridging of aquatic and human pathogen resistomes leads to emergence of new antimicrobial-resistant bacteria and global dissemination of them and their antimicrobial resistance genes into animal and human populations. Efforts to prevent antimicrobial overuse in aquaculture must include education of all stakeholders about its detrimental effects on the health of fish, human beings, and the aquatic ecosystem (the notion of One Health), and encouragement of environmentally friendly measures of disease prevention, including vaccines, probiotics, and bacteriophages. Adoption of these measures is a crucial supplement to efforts dealing with antimicrobial resistance by developing new therapeutic agents, if headway is to be made against the increasing problem of antimicrobial resistance in human and veterinary medicine.

  7. Combating Antimicrobial Resistance in Foodborne Microorganisms.

    Science.gov (United States)

    Lai, Edward P C; Iqbal, Zafar; Avis, Tyler J

    2016-02-01

    This review addresses an important public health hazard affecting food safety. Antimicrobial agents are used in foods to reduce or eliminate microorganisms that cause disease. Many traditional organic compounds, novel synthetic organic agents, natural products, peptides, and proteins have been extensively studied for their effectiveness as antimicrobial agents against foodborne Campylobacter spp., Escherichia coli, Listeria spp. and Salmonella. However, antimicrobial resistance can develop in microorganisms, enhancing their ability to withstand the inhibiting or killing action of antimicrobial agents. Knowledge gaps still exist with regard to the actual chemical and microbiological mechanisms that must be identified to facilitate the search for new antimicrobial agents. Technical implementation of antimicrobial active packing films and coatings against target microorganisms must also be improved for extended product shelf life. Recent advances in antimicrobial susceptibility testing can provide researchers with new momentum to pursue their quest for a resistance panacea.

  8. Uses of antimicrobial genes from microbial genome

    Science.gov (United States)

    Sorek, Rotem; Rubin, Edward M.

    2013-08-20

    We describe a method for mining microbial genomes to discover antimicrobial genes and proteins having broad spectrum of activity. Also described are antimicrobial genes and their expression products from various microbial genomes that were found using this method. The products of such genes can be used as antimicrobial agents or as tools for molecular biology.

  9. Antimicrobial resistance among enterococci from pigs in three European countries

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Hasman, Henrik; Jensen, Lars Bogø;

    2002-01-01

    Enterococci from pigs in Denmark, Spain, and Sweden were examined for susceptibility to antimicrobial agents and copper and the presence of selected resistance genes. The greatest levels of resistance were found among isolates from Spain and Denmark compared to those from Sweden, which correspond...

  10. Antimicrobial Resistance Pattern and Their Beta-Lactamase Encoding Genes among Pseudomonas aeruginosa Strains Isolated from Cancer Patients

    Directory of Open Access Journals (Sweden)

    Mai M. Zafer

    2014-01-01

    Full Text Available This study was designed to investigate the prevalence of metallo-β-lactamases (MBL and extended-spectrum β-lactamases (ESBL in P. aeruginosa isolates collected from two different hospitals in Cairo, Egypt. Antibiotic susceptibility testing and phenotypic screening for ESBLs and MBLs were performed on 122 P. aeruginosa isolates collected in the period from January 2011 to March 2012. MICs were determined. ESBLs and MBLs genes were sought by PCR. The resistant rate to imipenem was 39.34%. The resistance rates for P. aeruginosa to cefuroxime, cefoperazone, ceftazidime, aztreonam, and piperacillin/tazobactam were 87.7%, 80.3%, 60.6%, 45.1%, and 25.4%, respectively. Out of 122 P. aeruginosa, 27% and 7.4% were MBL and ESBL, respectively. The prevalence of blaVIM-2, blaOXA-10-, blaVEB-1, blaNDM-, and blaIMP-1-like genes were found in 58.3%, 41.7%, 10.4%, 4.2%, and 2.1%, respectively. GIM-, SPM-, SIM-, and OXA-2-like genes were not detected in this study. OXA-10-like gene was concomitant with VIM-2 and/or VEB. Twelve isolates harbored both OXA-10 and VIM-2; two isolates carried both OXA-10 and VEB. Only one strain contained OXA-10, VIM-2, and VEB. In conclusion, blaVIM-2- and blaOXA-10-like genes were the most prevalent genes in P. aeruginosa in Egypt. To our knowledge, this is the first report of blaVIM-2, blaIMP-1, blaNDM, and blaOXA-10 in P. aeruginosa in Egypt.

  11. Population structure and characterisation of Staphylococcus aureus from bacteraemia at multiple hospitals in China: association between antimicrobial resistance, toxin genes and genotypes.

    Science.gov (United States)

    He, Wenqiang; Chen, Hongbin; Zhao, Chunjiang; Zhang, Feifei; Li, Henan; Wang, Qi; Wang, Xiaojuan; Wang, Hui

    2013-09-01

    Staphylococcus aureus from bacteraemia at multiple hospitals in China were genetically characterised to improve understanding of its epidemiology. A total of 236 consecutive, non-duplicate S. aureus bacteraemia isolates were collected at 16 Chinese hospitals. Isolates were characterised by antimicrobial resistance, 19 toxin genes, agr alleles, multilocus sequence typing and spa typing. The prevalence of meticillin-resistant S. aureus (MRSA) was 47.5% (112/236). Forty-two sequence types (STs) and 63 spa types were identified, including 14 STs and 14 spa types for MRSA. Clonal complex (CC) 8, CC5, ST7 and CC188 accounted for 67.4% of the isolates. ST239-t030/t037-SCCmecIII-agrI was the predominant MRSA genotype (50%), followed by ST5-t002/t570-SCCmecII-agrII (8%). A vancomycin MIC ≥ 1mg/L was detected significantly more often in ST5-SCCmecII and ST239-t037-SCCmecIII, whereas rifampicin resistance was overwhelmingly associated with ST239-t030-SCCmecIII (Paureus (MSSA) were ST7-t091/t796-agrI (16.1%), ST188-t189-agrI (12.1%) and ST398-t571/t034-agrI (5.6%). Toxin genes were identified in 95.8% of isolates and formed 89 toxin gene profiles. The toxin genes sea, selk, selq and sell were significantly more common in MRSA, whilst tsst-1, seb, sed, selm, seln, selp and selj were more prevalent in MSSA (Ptoxin gene profiles.

  12. Dealing with antimicrobial resistance - the Danish experience

    DEFF Research Database (Denmark)

    Bager, Flemming; Aarestrup, Frank Møller; Wegener, Henrik Caspar

    2000-01-01

    Following the discovery in 1994 and 1995 that use of the glycopeptide antimicrobial avoparcin for growth promotion was associated with the occurrence of vancomycin resistant Enterococcus faecium in food animals and in food, the Danish Minister of Food, Agriculture and Fisheries banned the use...... of avoparcin in May 1995. The ban was later extended by the European Commission to include all EU member states. In May 1999, the EU Scientific Steering Committee recommended that use for growth promotion of antimicrobials, which are or may be used in human or veterinary medicine should be phased out as soon...... on the prudent use of antimicrobials in order to reduce the development of resistance without compromising therapeutic efficacy. Our experience with avoparcin shows that a restrictive policy on the use of antimicrobials can curb the development of resistance. However, the occurrence and persistence of specific...

  13. Human Health Hazards from Antimicrobial-Resistant Escherichia coli of Animal Origin

    DEFF Research Database (Denmark)

    Hammerum, A. M.; Heuer, Ole Eske

    2009-01-01

    Because of the intensive use of antimicrobial agents in food animal production, meat is frequently contaminated with antimicrobial-resistant Escherichia coli. Humans can be colonized with E. coli of animal origin, and because of resistance to commonly used antimicrobial agents, these bacteria may...... cause infections for which limited therapeutic options are available. This may lead to treatment failure and can have serious consequences for the patient. Furthermore, E. coli of animal origin may act as a donor of antimicrobial resistance genes for other pathogenic E. coli. Thus, the intensive use...... of antimicrobial agents in food animals may add to the burden of antimicrobial resistance in humans. Bacteria from the animal reservoir that carry resistance to antimicrobial agents that are regarded as highly or critically important in human therapy (e.g., aminoglycosides, fluoroquinolones, and third- and fourth...

  14. Danish Integrated Antimicrobial Resistance Monitoring and Research Program

    Science.gov (United States)

    Heuer, Ole E.; Emborg, Hanne-Dorthe; Bagger-Skjøt, Line; Jensen, Vibeke F.; Rogues, Anne-Marie; Skov, Robert L.; Agersø, Yvonne; Brandt, Christian T.; Seyfarth, Anne Mette; Muller, Arno; Hovgaard, Karin; Ajufo, Justin; Bager, Flemming; Aarestrup, Frank M.; Frimodt-Møller, Niels; Wegener, Henrik C.; Monnet, Dominique L.

    2007-01-01

    Resistance to antimicrobial agents is an emerging problem worldwide. Awareness of the undesirable consequences of its widespread occurrence has led to the initiation of antimicrobial agent resistance monitoring programs in several countries. In 1995, Denmark was the first country to establish a systematic and continuous monitoring program of antimicrobial drug consumption and antimicrobial agent resistance in animals, food, and humans, the Danish Integrated Antimicrobial Resistance Monitoring and Research Program (DANMAP). Monitoring of antimicrobial drug resistance and a range of research activities related to DANMAP have contributed to restrictions or bans of use of several antimicrobial agents in food animals in Denmark and other European Union countries. PMID:18217544

  15. Antimicrobial resistant bacteria in the food chain

    DEFF Research Database (Denmark)

    Wegener, Henrik Caspar

    2003-01-01

    Antimicrobials are used for treatment and prevention of disease in food animals and as feed additives for growth promotion. All uses lead to the development of resistant bacteria, some of which are pathogenic to humans. Current main concerns are with resistance in Salmonella and Campylobacter...

  16. Quantifying antimicrobial resistance at veal calf farms.

    Directory of Open Access Journals (Sweden)

    Angela B Bosman

    Full Text Available This study was performed to determine a sampling strategy to quantify the prevalence of antimicrobial resistance on veal calf farms, based on the variation in antimicrobial resistance within and between calves on five farms. Faecal samples from 50 healthy calves (10 calves/farm were collected. From each individual sample and one pooled faecal sample per farm, 90 selected Escherichia coli isolates were tested for their resistance against 25 mg/L amoxicillin, 25 mg/L tetracycline, 0.5 mg/L cefotaxime, 0.125 mg/L ciprofloxacin and 8/152 mg/L trimethoprim/sulfamethoxazole (tmp/s by replica plating. From each faecal sample another 10 selected E. coli isolates were tested for their resistance by broth microdilution as a reference. Logistic regression analysis was performed to compare the odds of testing an isolate resistant between both test methods (replica plating vs. broth microdilution and to evaluate the effect of pooling faecal samples. Bootstrap analysis was used to investigate the precision of the estimated prevalence of resistance to each antimicrobial obtained by several simulated sampling strategies. Replica plating showed similar odds of E. coli isolates tested resistant compared to broth microdilution, except for ciprofloxacin (OR 0.29, p ≤ 0.05. Pooled samples showed in general lower odds of an isolate being resistant compared to individual samples, although these differences were not significant. Bootstrap analysis showed that within each antimicrobial the various compositions of a pooled sample provided consistent estimates for the mean proportion of resistant isolates. Sampling strategies should be based on the variation in resistance among isolates within faecal samples and between faecal samples, which may vary by antimicrobial. In our study, the optimal sampling strategy from the perspective of precision of the estimated levels of resistance and practicality consists of a pooled faecal sample from 20 individual animals, of which

  17. Antimicrobial resistance in Scandinavia after ban of antimicrobial growth promoters.

    Science.gov (United States)

    Bengtsson, Björn; Wierup, Martin

    2006-01-01

    The banned use of antimicrobial growth promoters resulted in a considerably decreased use of antimicrobials in food animal production in Sweden (65%), Denmark (47%), Norway (40%) and Finland (27%). The current prevalence of antimicrobial resistance in animal bacterial populations is also considerably lower than in some other countries in the EU. In the swine production, no or limited effect was found in the finisher production (>25 to 30 kg). Temporary negative effects occurred during the post weaning period (7-30 kg). In Denmark, the cost of production from birth to slaughter per pig produced increased by approximately 1.0 euro with a high variability between pig producers. In the broiler production the termination had no significant negative effect on animal health and welfare or on production economy.

  18. Prevalence of antimicrobial resistance and integrons in Escherichia Coli from Punjab, Pakistan

    Directory of Open Access Journals (Sweden)

    Idrees Muhammad

    2011-06-01

    Full Text Available Antimicrobial resistance was studied in Escherichia coli strains isolated from urine samples of 457 patients suffering from urinary tract infection. High prevalence of class 1 integrons (43.56%, sulfamethoxazole resistance genes sul1 (45.54% and sul2 (51.48% along with occurrence of quinolone resistance genes was detected in multi drug resistance isolates.

  19. DNA microarray genotyping and virulence and antimicrobial resistance gene profiling of methicillin-resistant Staphylococcus aureus bloodstream isolates from renal patients.

    LENUS (Irish Health Repository)

    McNicholas, Sinead

    2012-02-01

    Thirty-six methicillin-resistant Staphylococcus aureus (MRSA) bloodstream isolates from renal patients were genetically characterized by DNA microarray analysis and spa typing. The isolates were highly clonal, belonging mainly to ST22-MRSA-IV. The immune evasion and enterotoxin gene clusters were found in 29\\/36 (80%) and 33\\/36 (92%) isolates, respectively.

  20. DNA microarray genotyping and virulence and antimicrobial resistance gene profiling of methicillin-resistant Staphylococcus aureus bloodstream isolates from renal patients.

    LENUS (Irish Health Repository)

    McNicholas, Sinead

    2011-12-01

    Thirty-six methicillin-resistant Staphylococcus aureus (MRSA) bloodstream isolates from renal patients were genetically characterized by DNA microarray analysis and spa typing. The isolates were highly clonal, belonging mainly to ST22-MRSA-IV. The immune evasion and enterotoxin gene clusters were found in 29\\/36 (80%) and 33\\/36 (92%) isolates, respectively.

  1. Clinical impact of antimicrobial resistance in animals.

    Science.gov (United States)

    Vaarten, J

    2012-04-01

    It is almost impossible to imagine veterinary medicine today without the use of antimicrobials. Shortly after their discovery, antimicrobials found their way into the veterinary world. They have brought many benefits for the health and welfare of both animals and people, such as the lessening of pain and suffering, reduction in shedding of (zoonotic) bacteria and the containment of potentially large-scale epidemics. Indirectly, they also contribute to food security, protection of livelihoods and animal resources, and poverty alleviation. Given the broad range of animal species under veterinary care and the enormous variety of infectious agents, a complete range of antimicrobials is needed in veterinary medicine. Losing products, either through the occurrence of resistance or through a prohibition on their use, will have serious consequences for the health and welfare of all animals. It will also seriously affect people who depend on these animals. It is a great challenge to everyone involved to stop the growing trend of antimicrobial resistance and to safeguard the effectiveness of antimicrobials for the future. Transparent and responsible use of antimicrobials, together with continuous monitoring and surveillance of the occurrence of resistance, are key elements of any strategy. The current situation also urges us to re-think unsustainable practices and to work on the development of alternatives, in the interests of the health and welfare of both animals and people. PMID:22849278

  2. Antimicrobial resistance of bacterial strains isolated from avian cellulitis

    Directory of Open Access Journals (Sweden)

    MM Santos

    2014-03-01

    Full Text Available Avian cellulitis is an inflammatory process in the subcutaneous tissue, mainly located in the abdomen and thighs. This problem is commonly observed in poultry at slaughter and it is considered one of the major causes of condemnation of carcasses in Brazil. The aim of this study was to perform the microbial isolation of lesions of avian cellulitis from a processing plant located in the State of Goiás in order to analyze antimicrobial resistance by antibiogram test and to detect resistance genes by polymerase chain reaction. A total of 25 samples of avian cellulitis lesions were analyzed, from which 30 bacterial strains were isolated. There were eleven (44% strains of Escherichia coli, nine (36% strains of Staphylococcus epidermidis, seven (28% strains of Proteus mirabilis and three (12% strains of Manheimiahaemolytica. The antibiogram test showed that all strains were resistant to at least one antimicrobial. The gene of antimicrobial resistance tetB was detected in E. coli, S. epidermidis and P. mirabilis strains, and was the most frequently observed gene. The gene of antimicrobial resistance Sul1 was detected in all bacterial species, while tetA was found in E. coli and S. epidermidis strains, SHV in E. coli strains, S. epidermidis and P. mirabilis,and cat1 in one P. mirabilis strain. The results suggest a potential public health hazard due to the ability of these microorganisms to transmit antimicrobial resistancegenes to other microorganisms present in the intestinal tract of humans and animals, which may affect clinical-medical usage of these drugs.

  3. Occurrence of integrons and resistance genes among sulphonamide-resistant Shigella spp. from Brazil

    DEFF Research Database (Denmark)

    Peirano, G.; Agersø, Yvonne; Aarestrup, Frank Møller;

    2005-01-01

    Objectives: To determine the occurrence of class 1 and 2 integrons and antimicrobial resistance genes among sulphonamide-resistant Shigella strains isolated in Brazil during 1999-2003. Methods: Sixty-two Shigella (Shigella flexneri, n = 47 and Shigella sonnei, n = 15) were tested against 21....... Conclusions: The detection of class 1 and 2 integrons and additional antimicrobial resistance genes allowed us to identify the most frequent antimicrobial resistance patterns of Shigella spp. isolated in Brazil....

  4. Veterinary drug usage and antimicrobial resistance in bacteria of animal origin

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller

    2005-01-01

    countries, which leaves room for considerable reductions in some countries. The emergence of resistant bacteria and resistance genes due to the use of antimicrobial agents are well documented. In Denmark it has been possible to reduce the usage of antimicrobial agents for food animals significantly...

  5. Dana Cole, Georgia Division of Public Health, Notifiable Disease Section, Department of Human Resources, 2 Peachtree Free-living Canada Geese and Antimicrobial Resistance

    OpenAIRE

    Cole, Dana; Drum, David J.V.; Stallknecht, David E.; White, David G.; Lee, Margie D.; Ayers, Sherry; Sobsey, Mark; Maurer, John J

    2005-01-01

    We describe antimicrobial resistance among Escherichia coli isolated from free-living Canada Geese in Georgia and North Carolina (USA). Resistance patterns are compared to those reported by the National Antimicrobial Resistance Monitoring System. Canada Geese may be vectors of antimicrobial resistance and resistance genes in agricultural environments.

  6. Understanding the mechanisms and drivers of antimicrobial resistance.

    Science.gov (United States)

    Holmes, Alison H; Moore, Luke S P; Sundsfjord, Arnfinn; Steinbakk, Martin; Regmi, Sadie; Karkey, Abhilasha; Guerin, Philippe J; Piddock, Laura J V

    2016-01-01

    To combat the threat to human health and biosecurity from antimicrobial resistance, an understanding of its mechanisms and drivers is needed. Emergence of antimicrobial resistance in microorganisms is a natural phenomenon, yet antimicrobial resistance selection has been driven by antimicrobial exposure in health care, agriculture, and the environment. Onward transmission is affected by standards of infection control, sanitation, access to clean water, access to assured quality antimicrobials and diagnostics, travel, and migration. Strategies to reduce antimicrobial resistance by removing antimicrobial selective pressure alone rely upon resistance imparting a fitness cost, an effect not always apparent. Minimising resistance should therefore be considered comprehensively, by resistance mechanism, microorganism, antimicrobial drug, host, and context; parallel to new drug discovery, broad ranging, multidisciplinary research is needed across these five levels, interlinked across the health-care, agriculture, and environment sectors. Intelligent, integrated approaches, mindful of potential unintended results, are needed to ensure sustained, worldwide access to effective antimicrobials. PMID:26603922

  7. A European study on the relationship between antimicrobial use and antimicrobial resistance

    NARCIS (Netherlands)

    Bronzwaer, SLAM; Cars, O; Buchholz, U; Molstad, S; Goettsch, W; Veldhuijzen, IK; Kool, JL; Sprenger, MJW; Degener, JE

    2002-01-01

    In Europe, antimicrobial resistance has been monitored since 1998 by the European Antimicrobial Resistance Surveillance System (EARSS). We examined the relationship between penicillin nonsusceptibility of invasive isolates of Streptococcus pneumoniae and antibiotic sales. Information was collected o

  8. Antimicrobial resistance in Libya: 1970-2011.

    Science.gov (United States)

    Ghenghesh, Khalifa Sifaw; Rahouma, Amal; Tawil, Khaled; Zorgani, Abdulaziz; Franka, Ezzedin

    2013-01-01

    Resistance to antimicrobial agents is a major health problem that affects the whole world. Providing information on the past state of antimicrobial resistance in Libya may assist the health authorities in addressing the problem more effectively in the future. Information was obtained mainly from Highwire Press (including PubMed) search for the period 1970-2011 using the terms 'antibiotic resistance in Libya', 'antimicrobial resistance in Libya', 'tuberculosis in Libya', and 'primary and acquired resistance in Libya' in title and abstract. From 1970 to 2011 little data was available on antimicrobial resistance in Libya due to lack of surveillance and few published studies. Available data shows high resistance rates for Salmonella species in the late 1970s and has remained high to the present day. High prevalence rates (54-68%) of methicillin-resistant Staphylococcus aureus (MRSA) were reported in the last decade among S. aureus from patients with burns and surgical wound infections. No reports were found of vancomycin-resistant S. aureus (VRSA) or vancomycin-intermediate-resistant S. aureus (VISA) using standard methods from Libya up to the end of 2011. Reported rates of primary (i.e. new cases) and acquired (i.e. retreatment cases) multidrug-resistant tuberculosis (MDR-TB) from the eastern region of Libya in 1971 were 16.6 and 33.3% and in 1976 were 8.6 and 14.7%, in western regions in 1984-1986 were 11 and 21.5% and in the whole country in 2011 were estimated at 3.4 and 29%, respectively. The problem of antibiotic resistance is very serious in Libya. The health authorities in particular and society in general should address this problem urgently. Establishing monitoring systems based on the routine testing of antimicrobial sensitivity and education of healthcare workers, pharmacists, and the community on the health risks associated with the problem and benefits of prudent use of antimicrobials are some steps that can be taken to tackle the problem in the future.

  9. Source-Related Effects of Wastewater on Transcription Factor (AhR, CAR and PXR-Mediated Induction of Gene Expression in Cultured Rat Hepatocytes and Their Association with the Prevalence of Antimicrobial-Resistant Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Keerthi S Guruge

    Full Text Available Extracts of wastewater collected from 4 sewage treatment plants (STPs receiving effluents from different sources in South India were investigated for their levels of transcription factor-mediated gene induction in primary cultured rat hepatocytes. In addition, the relation between gene induction levels and the prevalence of antimicrobial-resistant Escherichia coli (E. coli in wastewater was examined. STP-3, which treats only hospital wastewater, exhibited significantly greater induction potency of all 6 drug metabolizing cytochrome P450 (CYP genes examined, CYP1A1, 1A2, 1B1, 2B15, 3A1, and 3A2, whereas the wastewater at STP-1, which exclusively receives domestic sewage, showed significantly diminished levels of induction of 3 CYP genes when compared to the levels of CYP induction at STP-2, which receives mixed wastewater. Samples collected during the monsoon season showed a significantly altered gene induction capacity compared to that of samples from the pre-monsoon period. The data suggest that the toxicity of wastewater in STPs was not significantly diminished during the treatment process. The chemical-gene interaction data predicted that a vast number of chemicals present in the wastewater would stimulate the genes studied in the rat hepatocytes. The multivariable logistic regression analysis demonstrated that the prevalence of isolates resistant to cefotaxime, imipenem and streptomycin was significantly correlated with the levels of induction of at least three CYP-isozymes in STP wastewater. In addition, the resistance of isolates in treatment plants was not altered by the treatment steps, whereas the sampling season did have an impact on the resistance to specific antimicrobials. The identification of receptor-mediated gene regulation capacities offers important data not limited to the (synergistic physiological role of chemicals in biological systems but may provide new insight into the link between the effects of known/unknown drugs and

  10. Intrinsic Antimicrobial Resistance Determinants in the Superbug Pseudomonas aeruginosa

    Science.gov (United States)

    Murray, Justine L.; Kwon, Taejoon; Marcotte, Edward M.

    2015-01-01

    ABSTRACT Antimicrobial-resistant bacteria pose a serious threat in the clinic. This is particularly true for opportunistic pathogens that possess high intrinsic resistance. Though many studies have focused on understanding the acquisition of bacterial resistance upon exposure to antimicrobials, the mechanisms controlling intrinsic resistance are not well understood. In this study, we subjected the model opportunistic superbug Pseudomonas aeruginosa to 14 antimicrobials under highly controlled conditions and assessed its response using expression- and fitness-based genomic approaches. Our results reveal that gene expression changes and mutant fitness in response to sub-MIC antimicrobials do not correlate on a genomewide scale, indicating that gene expression is not a good predictor of fitness determinants. In general, fewer fitness determinants were identified for antiseptics and disinfectants than for antibiotics. Analysis of gene expression and fitness data together allowed the prediction of antagonistic interactions between antimicrobials and insight into the molecular mechanisms controlling these interactions. PMID:26507235

  11. Azorean wild rabbits as reservoirs of antimicrobial resistant Escherichia coli.

    Science.gov (United States)

    Marinho, Catarina; Igrejas, Gilberto; Gonçalves, Alexandre; Silva, Nuno; Santos, Tiago; Monteiro, Ricardo; Gonçalves, David; Rodrigues, Tiago; Poeta, Patrícia

    2014-12-01

    Antibiotic resistance in bacteria is an increasing problem that is not only constrained to the clinical setting but also to other environments that can lodge antibiotic resistant bacteria and therefore they may serve as reservoirs of genetic determinants of antibiotic resistance. One hundred and thirty-six faecal samples from European wild rabbits (Oryctolagus cuniculus algirus) were collected on São Jorge Island in Azores Archipelago, and analysed for Escherichia coli isolates. Seventy-seven isolates (56.6%) were recovered and studied for antimicrobial resistance, one isolate per positive sample. Thirteen (16.9%), 19 (24.7%), 25 (32.4%) and 20 (26%) isolates were ascribed to A, B1, B2 and D phylogenetic groups, respectively, by specific primer polymerase chain reaction. Different E. coli isolates were found to be resistant to ampicillin (16.9%), tetracycline (1.3%), streptomycin (42.9%), sulfamethoxazole-trimethoprim (1.3%), amikacin (1.3%), tobramycin (2.6%) and nalidixic acid (1.3%). Additionally, the blaTEM, tetA, strA/strB, aadA, sul1, intI, intI2 and qacEΔ+sul1 genes were found in most resistant isolates. This study showed that E. coli from the intestinal tract of wild rabbits from Azores Archipelago are resistant to widely prescribed antibiotics in medicine and they constitute a reservoir of antimicrobial resistant genes, which may play a significant role in the spread of antimicrobial resistance. Therefore, antibiotic resistant E. coli from Azorean wild rabbits may represent an ecological and public health problem.

  12. Identification and Antimicrobial Resistance of Bacteria Isolated from Probiotic Products Used in Shrimp Culture

    DEFF Research Database (Denmark)

    Noor Uddin, Gazi Md; Larsen, Marianne Halberg; Christensen, Henrik;

    2015-01-01

    Probiotics are increasingly used in aquaculture to control diseases and improve feed digestion and pond water quality; however, little is known about the antimicrobial resistance properties of such probiotic bacteria and to what extent they may contribute to the development of bacterial resistance...... antimicrobial resistance and associated transferable resistance genes. The bacterial species was established by 16S rRNA sequence analysis of 125 representative bacterial isolates. MIC testing was done for a range of antimicrobials and whole genome sequencing of six multiple antimicrobial resistant Bacillus spp...... missed a few bacterial species present in the tested products this would represent minor bias, but future studies may apply culture independent identification methods like pyro sequencing. Only 6/60 isolates were resistant to more than four antimicrobials and whole genome sequencing showed...

  13. EMERGING ANTIMICROBIAL RESISTANCE IN HOSPITAL A THREAT TO PUBLIC HEALTH

    OpenAIRE

    Vichal Rastogi; Pankaj Kumar Mishra; Shalini Bhatia

    2013-01-01

    Background: Antimicrobial resistance(AMR) threatens the health of many throughout the world, since both old and new infectious diseases remain a formidable public health threat. When pathogenic microorganisms can multiply beyond some critical mass in the face of invading antimicrobials, treatment outcome is compromised. This phenomenon is referred as antimicrobial resistance (AMR). Objective: This retrospective study was conducted to assess the overall antimicrobial resistance in bacteri...

  14. Resistance of potential probiotic lactic acid bacteria and bifidobacteria of African and European origin to antimicrobials: Determination and transferability of the resistance genes to other bacteria

    DEFF Research Database (Denmark)

    Ouoba, Labia Irene Ivette; Lei, Vicki; Jensen, Lars Bogø

    2008-01-01

    Probiotic bacteria and starter cultures of Lactobacillus, Weissella and Bifidobacterium of African and European origins were studied and compared for their susceptibility to antimicrobials. The study included, for all isolates, determination of MICs (Minimal Inhibitory Concentration) for 24...

  15. A brief multi-disciplinary review on antimicrobial resistance in medicine and its linkage to the global environmental microbiota.

    OpenAIRE

    LeonCantas; LinaM.Cavaco; CéliaManaia; FionaWalsh; MagdalenaPopowska; HemdaGarelick; HelmutBürgmann

    2013-01-01

    The discovery and introduction of antimicrobial agents to clinical medicine was one of the greatest medical triumphs of the 20th century that revolutionized the treatment of bacterial infections. However, the gradual emergence of populations of antimicrobial-resistant pathogenic bacteria resulting from use, misuse and abuse of antimicrobials has today become a major global health concern. Antimicrobial resistance genes have been suggested to originate from environmental bacteria, as clinicall...

  16. Marine echinoderms as reservoirs of antimicrobial resistant bacteria

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    Catarina Marinho

    2014-06-01

    able to spread their genes into aquatic microorganisms, which may also contain resistance genes. Furthermore, it is known that several antibiotics from industrial sources circulate in water environments, potentially altering microbial ecosystems (Baquero et al., 2008. Once antibiotics enter the ecosystem, they can act as an ecological factor, eradicating susceptible and promoting resistant species and strains (Aminov and Mackie, 2007. The study of antibiotic resistance in aquatic organisms is pertinent, as it might indicate the variation amount of aquatic ecosystems with presumable human action. Aquatic environment play an important role in the spreading and evolution of antibiotic resistant bacteria. In this way, bacteria from different origins are able to interact, and antibiotic resistance improves as a consequence of uncontrolled exchange and shuffling of genes, genetic elements, and genetic vectors (Baquero et al., 2008. The need for monitoring and evaluate bacteria susceptibility to antibiotics in humans, animals and the environment is considered as a measure to contest the increasing of antimicrobial resistance (WHO, 2001. Enterococcus spp. and Escherichia coli mostly do not cause disease, but they may act as a reservoir of antimicrobial-resistance genes that could be transmitted to other pathogenic bacteria. In fact, both Enterococcus spp. and E. coli are experts in acquiring and transmitting resistance genes, even to phylogenetically distant bacteria, representing a worldwide concern (Martel et al., 2003, Costa et al., 2006. Enterococcus spp. is more frequently isolated from echinoderms fecal samples than E. coli bacteria, which may be due to the fact that E. coli are Gram-negative bacteria that typically are more susceptible to adverse conditions than Gram-positive bacteria (Marinho et al., 2013, Wan et al., 2009. The highest percentage of antibiotic resistance exhibited on enterococci isolates was to erythromycin, ampicillin, tetracycline, and ciprofloxacin

  17. ANTIMICROBIAL RESISTANCE AND ITS GLOBAL SPREAD

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    R P Sharma

    2010-06-01

    Full Text Available Since their discovery during the 20th century, antimicrobial agents (antibiotics and related medicinal drugs have substantially reduced the threat posed by infectious diseases. The use of these “wonder drugs”, combined with improvements in sanitation, housing, and nutrition, and the advent of widespread immunization programmes, has led to a dramatic drop in deaths from diseases that were previously widespread, untreatable, and frequently fatal. Over the years, antimicrobials have saved the lives and eased the suffering of millions of people. By helping to bring many serious infectious diseases under control, these drugs hav also contributed to the major gains in life expectancy experienced during the latter part of the last century. These gains are now seriously jeopardized by another recent development: the emergence and spread of microbes that are resistant to cheap and effective first-choice, or “first- line” drugs. The bacterial infections which contribute most to human disease are also those in which emerging microbial resistance is most evident: diarrhoeal diseases, respiratory tract infections, meningitis, sexually transmitted infections, and hospital-acquired infections. Some important examples include penicillin-resistant Streptococcus pneumoniae, vancomycin-resistant enterococci, methicillin-resistant Staphylococcus aureus, multi-resistant salmonellae, and multi-resistant Mycobacterium tuberculosis. The development of resistance to drugs commonly used to treat malaria is of particular concern, as is the emerging resistance to anti-HIV drugs. Treatment, resu.lting in prolonged illness and greater risk of death, Treatment failures also lead to longer periods of infectivity, which increase the numbers of infected people moving in the community and thus expose the general population to the risk of contracting a resistant strain of infection. When infections become resistant to first-line antimicrobials, treatment has to be switched

  18. Antimicrobial resistances do not affect colonization parameters of intestinal E. coli in a small piglet group

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    Schierack Peter

    2009-10-01

    Full Text Available Abstract Background Although antimicrobial resistance and persistence of resistant bacteria in humans and animals are major health concerns worldwide, the impact of antimicrobial resistance on bacterial intestinal colonization in healthy domestic animals has only been rarely studied. We carried out a retrospective analysis of the antimicrobial susceptibility status and the presence of resistance genes in intestinal commensal E. coli clones from clinically healthy pigs from one production unit with particular focus on effects of pheno- and/or genotypic resistance on different nominal and numerical intestinal colonization parameters. In addition, we compared the occurrence of antimicrobial resistance phenotypes and genotypes with the occurrence of virulence associated genes typical for extraintestinal pathogenic E. coli. Results In general, up to 72.1% of all E. coli clones were resistant to ampicillin, chloramphenicol, kanamycin, streptomycin, sulfamethoxazole or tetracycline with a variety of different resistance genes involved. There was no significant correlation between one of the nominal or numerical colonization parameters and the absence or presence of antimicrobial resistance properties or resistance genes. However, there were several statistically significant associations between the occurrence of single resistance genes and single virulence associated genes. Conclusion The demonstrated resistance to the tested antibiotics might not play a dominant role for an intestinal colonization success in pigs in the absence of antimicrobial drugs, or cross-selection of other colonization factors e.g. virulence associated genes might compensate "the cost of antibiotic resistance". Nevertheless, resistant strains are not outcompeted by susceptible bacteria in the porcine intestine. Trial Registration The study was approved by the local animal welfare committee of the "Landesamt für Arbeitsschutz, Gesundheitsschutz und technische Sicherheit" Berlin

  19. Klebsiella pneumoniae Antimicrobial Drug Resistance, United States, 1998–2010

    OpenAIRE

    Sanchez, Guillermo V.; Master, Ronald N; Clark, Richard B.; Fyyaz, Madiha; Duvvuri, Padmaraj; Ekta, Gupta; Bordon, Jose

    2013-01-01

    We studied antimicrobial-resistant Klebsiella pneumoniae for 1998–2010 by using data from The Surveillance Network. Susceptibility results (n = 3,132,354) demonstrated significant increases in resistance to all antimicrobial drugs studied, except tetracycline. Cross-resistance among carbapenem-resistant K. pneumoniae was lower for tetracycline and amikacin.

  20. Resistance to Antimicrobial Peptides in Vibrios

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    Delphine Destoumieux-Garzón

    2014-10-01

    Full Text Available Vibrios are associated with a broad diversity of hosts that produce antimicrobial peptides (AMPs as part of their defense against microbial infections. In particular, vibrios colonize epithelia, which function as protective barriers and express AMPs as a first line of chemical defense against pathogens. Recent studies have shown they can also colonize phagocytes, key components of the animal immune system. Phagocytes infiltrate infected tissues and use AMPs to kill the phagocytosed microorganisms intracellularly, or deliver their antimicrobial content extracellularly to circumvent tissue infection. We review here the mechanisms by which vibrios have evolved the capacity to evade or resist the potent antimicrobial defenses of the immune cells or tissues they colonize. Among their strategies to resist killing by AMPs, primarily vibrios use membrane remodeling mechanisms. In particular, some highly resistant strains substitute hexaacylated Lipid A with a diglycine residue to reduce their negative surface charge, thereby lowering their electrostatic interactions with cationic AMPs. As a response to envelope stress, which can be induced by membrane-active agents including AMPs, vibrios also release outer membrane vesicles to create a protective membranous shield that traps extracellular AMPs and prevents interaction of the peptides with their own membranes. Finally, once AMPs have breached the bacterial membrane barriers, vibrios use RND efflux pumps, similar to those of other species, to transport AMPs out of their cytoplasmic space.

  1. Oral biofilms: a reservoir of transferable, bacterial, antimicrobial resistance.

    Science.gov (United States)

    Roberts, Adam P; Mullany, Peter

    2010-12-01

    Oral microbes are responsible for dental caries and periodontal diseases and have also been implicated in a range of other diseases beyond the oral cavity. These bacteria live primarily as complex, polymicrobial biofilms commonly called dental plaque. Cells growing within a biofilm often exhibit altered phenotypes, such as increased antibiotic resistance. The stable structural properties and close proximity of the bacterial cells within the biofilm appears to be an excellent environment for horizontal gene transfer, which can lead to the spread of antibiotic resistance genes amongst the biofilm inhabitants. This article will present an overview of the different types and amount of resistance to antibiotics that have been found in the human oral microbiota and will discuss the oral inhabitants' role as a reservoir of antimicrobial resistance genes. In addition, data on the genetic support for these resistance genes will be detailed and the evidence for horizontal gene transfer reviewed, demonstrating that the bacteria inhabiting the oral cavity are a reservoir of transferable antibiotic resistance.

  2. Using data on resistance prevalence per sample in the surveillance of antimicrobial resistance

    DEFF Research Database (Denmark)

    Vieira, Antonio; Shuyu, Wu; Jensen, Lars Bogø;

    2008-01-01

    Objectives: In most existing antimicrobial resistance monitoring programmes, one single bacterial colony from each collected sample is susceptibility tested against a panel of antimicrobials. Detecting the proportion of colonies resistant to different antimicrobials in each sample can provide...... and occurrence of resistance, there is a need to move towards a more quantitative approach when dealing with antimicrobial resistance in a population, and the resistance prevalence per sample method can provide some of this additional information....

  3. Antimicrobial Resistance of Escherichia fergusonii Isolated from Broiler Chickens.

    Science.gov (United States)

    Simmons, Karen; Islam, M Rashedul; Rempel, Heidi; Block, Glenn; Topp, Edward; Diarra, Moussa S

    2016-06-01

    The objective of this study was to investigate the antibiotic resistance of Escherichia fergusonii isolated from commercial broiler chicken farms. A total of 245 isolates from cloacal and cecal samples of 28- to 36-day-old chickens were collected from 32 farms. Isolates were identified using PCR, and their susceptibility to 16 antibiotics was determined by disk diffusion assay. All isolates were susceptible to meropenem, amikacin, and ciprofloxacin. The most common resistances were against ampicillin (75.1%), streptomycin (62.9%), and tetracycline (57.1%). Of the 184 ampicillin-resistant isolates, 127 were investigated using a DNA microarray carrying 75 probes for antibiotic resistance genetic determinants. Of these 127 isolates, the β-lactamase blaCMY2, blaTEM, blaACT, blaSHV, and blaCTX-M-15 genes were detected in 120 (94.5%), 31 (24.4%), 8 (6.3%), 6 (4.7%), and 4 (3.2%) isolates, respectively. Other detected genes included those conferring resistance to aminoglycosides (aadA1, strA, strB), trimethoprims (dfrV, dfrA1), tetracyclines (tetA, tetB, tetC, tetE), and sulfonamides (sul1, sul2). Class 1 integron was found in 35 (27.6%) of the ampicillin-resistant isolates. However, our data showed that the tested E. fergusonii did not carry any carbapenemase blaOXA genes. Pulsed-field gel electrophoresis revealed that the selected ampicillin-resistant E. fergusonii isolates were genetically diverse. The present study indicates that the monitoring of antimicrobial-resistant bacteria should include enteric bacteria such as E. fergusonii, which could be a reservoir of antibiotic resistance genes. The detection of isolates harboring extended-spectrum β-lactamase genes, particularly blaCTX-M-15, in this work suggests that further investigations on the occurrence of such genes in broilers are warranted.

  4. Salt-resistant short antimicrobial peptides.

    Science.gov (United States)

    Mohanram, Harini; Bhattacharjya, Surajit

    2016-05-01

    Antimicrobial peptides (AMPs) are promising leads for the development of antibiotics against drug resistant bacterial pathogens. However, in vivo applications of AMPs remain obscure due to salt and serum mediated inactivation. The high cost of chemical synthesis of AMPs also impedes potential clinical application. Consequently, short AMPs resistant toward salt and serum inactivation are desirable for the development of peptide antibiotics. In this work, we designed a 12-residue amphipathic helical peptide RR12 (R-R-L-I-R-L-I-L-R-L-L-R-amide) and two Trp containing analogs of RR12 namely RR12Wpolar (R-R-L-I-W-L-I-L-R-L-L-R-amide), and RR12Whydro (R-R-L-I-R-L-W-L-R-L-L-R-amide). Designed peptides demonstrated potent antibacterial activity; MIC ranging from 2 to 8 μM, in the presence of sodium chloride (150 mM and 300 mM). Antibacterial activity of these peptides was also detected in the presence of human serum. Designed peptides, in particular RR12 and RR12Whydro, were only poorly hemolytic. As a mode of action; these peptides demonstrated efficient permeabilization of bacterial cell membrane and lysis of cell structure. We further investigated interactions of the designed peptides with lipopolysaccharide (LPS), the major component of the outer membrane permeability barrier of Gram-negative bacteria. Designed peptides adopted helical conformations in complex with LPS. Binding of peptides with LPS has yielded dissociation the aggregated structures of LPS. Collectively, these designed peptides hold ability to be developed for salt-resistant antimicrobial compounds. Most importantly, current work provides insights for designing salt-resistant antimicrobial peptides. © 2016 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 345-356, 2016. PMID:26849911

  5. Antimicrobial resistance profiles and genetic characterisation of macrolide resistant isolates of Streptococcus agalactiae

    Directory of Open Access Journals (Sweden)

    Priscila AM Nakamura

    2011-03-01

    Full Text Available In this study, 100 clinical isolates of Streptococcus agalactiae recovered from genitourinary tract specimens of non-pregnant individuals living in Rio de Janeiro were submitted for antimicrobial susceptibility testing, detection of macrolide resistance genes and evaluation of the genetic diversity of erythromycin-resistant isolates. By agar diffusion method, all isolates were susceptible to ceftazidime, penicillin and vancomycin. Isolates were resistant to levofloxacin (1%, clindamycin (5%, erythromycin (11% and tetracycline (83% and were intermediated to erythromycin (4% and tetracycline (6%. Erythromycin-resistant and intermediated isolates presented the following phenotypes: M (n = 3, constitutive macrolide-lincosamide-streptogramin B (MLS B, n = 5 and inductive MLS B (n = 7. Determinants of macrolide resistance genes, erm and mef, were detected in isolates presenting MLS B and M phenotypes, respectively. Randomly amplified polymorphic DNA profiles of erythromycin-resistant isolates were clustered into two major groups of similarity.

  6. Distribution of antimicrobial-resistant lactic acid bacteria in natural cheese in Japan.

    Science.gov (United States)

    Ishihara, Kanako; Nakajima, Kumiko; Kishimoto, Satoko; Atarashi, Fumiaki; Muramatsu, Yasukazu; Hotta, Akitoyo; Ishii, Satomi; Takeda, Yasuyuki; Kikuchi, Masanori; Tamura, Yutaka

    2013-10-01

    To determine and compare the extent of contamination caused by antimicrobial-resistant lactic acid bacteria (LAB) in imported and domestic natural cheeses on the Japanese market, LAB were isolated using deMan, Rogosa and Sharpe (MRS) agar and MRS agar supplemented with six antimicrobials. From 38 imported and 24 Japanese cheeses, 409 LAB isolates were obtained and their antimicrobial resistance was tested. The percentage of LAB resistant to dihydrostreptomycin, erythromycin, and/or oxytetracycline isolated from imported cheeses (42.1%) was significantly higher than that of LAB resistant to dihydrostreptomycin or oxytetracycline from cheeses produced in Japan (16.7%; P=0.04). Antimicrobial resistance genes were detected in Enterococcus faecalis (tetL, tetM, and ermB; tetL and ermB; tetM) E. faecium (tetM), Lactococcus lactis (tetS), Lactobacillus (Lb.), casei/paracasei (tetM or tetW), and Lb. rhamnosus (ermB) isolated from seven imported cheeses. Moreover, these E. faecalis isolates were able to transfer antimicrobial resistance gene(s). Although antimicrobial resistance genes were not detected in any LAB isolates from Japanese cheeses, Lb. casei/paracasei and Lb. coryniformis isolates from a Japanese farm-made cheese were resistant to oxytetracycline (minimal inhibitory concentration [MIC], 32 µg/mL). Leuconostoc isolates from three Japanese farm-made cheeses were also resistant to dihydrostreptomycin (MIC, 32 to >512 µg/mL). In conclusion, the present study demonstrated contamination with antimicrobial-resistant LAB in imported and Japanese farm-made cheeses on the Japanese market, but not in Japanese commercial cheeses.

  7. The challenges of antimicrobial resistance in Brazil.

    Science.gov (United States)

    Rossi, Flávia

    2011-05-01

    Brazil is a country with continental proportions with high geographic and economic diversity. Despite its medical centers of excellence, antimicrobial resistance poses a major therapeutic challenge. Rates of methicillin-resistant Staphylococcus aureus are up to 60% and are related to an endemic Brazilian clone. Local resistance to vancomycin in Enterococci was first related to Enterococcus faecalis, which differs from European and American epidemiology. Also, local Klebsiella pneumoniae and Escherichia coli isolates producing extended-spectrum β-lactamases have a much higher prevalence (40%-50% and 10%-18%, respectively). Carbapenem resistance among the enterobacteriaceae group is becoming a major problem, and K. pneumoniae carbapenemase isolates have been reported in different states. Among nonfermenters, carbapenem resistance is strongly related to SPM-1 (Pseudomonasaeruginosa) and OXA-23 (Acinetobacter baumannii complex) enzymes, and a colistin-only susceptible phenotype has also emerged in these isolates, which is worrisome. Local actions without loosing the global resistance perspective will demand multidisciplinary actions, new policies, and political engagement.

  8. Whole-Genome Sequencing Analysis Accurately Predicts Antimicrobial Resistance Phenotypes in Campylobacter spp.

    Science.gov (United States)

    Zhao, S; Tyson, G H; Chen, Y; Li, C; Mukherjee, S; Young, S; Lam, C; Folster, J P; Whichard, J M; McDermott, P F

    2016-01-01

    The objectives of this study were to identify antimicrobial resistance genotypes for Campylobacter and to evaluate the correlation between resistance phenotypes and genotypes using in vitro antimicrobial susceptibility testing and whole-genome sequencing (WGS). A total of 114 Campylobacter species isolates (82 C. coli and 32 C. jejuni) obtained from 2000 to 2013 from humans, retail meats, and cecal samples from food production animals in the United States as part of the National Antimicrobial Resistance Monitoring System were selected for study. Resistance phenotypes were determined using broth microdilution of nine antimicrobials. Genomic DNA was sequenced using the Illumina MiSeq platform, and resistance genotypes were identified using assembled WGS sequences through blastx analysis. Eighteen resistance genes, including tet(O), blaOXA-61, catA, lnu(C), aph(2″)-Ib, aph(2″)-Ic, aph(2')-If, aph(2″)-Ig, aph(2″)-Ih, aac(6')-Ie-aph(2″)-Ia, aac(6')-Ie-aph(2″)-If, aac(6')-Im, aadE, sat4, ant(6'), aad9, aph(3')-Ic, and aph(3')-IIIa, and mutations in two housekeeping genes (gyrA and 23S rRNA) were identified. There was a high degree of correlation between phenotypic resistance to a given drug and the presence of one or more corresponding resistance genes. Phenotypic and genotypic correlation was 100% for tetracycline, ciprofloxacin/nalidixic acid, and erythromycin, and correlations ranged from 95.4% to 98.7% for gentamicin, azithromycin, clindamycin, and telithromycin. All isolates were susceptible to florfenicol, and no genes associated with florfenicol resistance were detected. There was a strong correlation (99.2%) between resistance genotypes and phenotypes, suggesting that WGS is a reliable indicator of resistance to the nine antimicrobial agents assayed in this study. WGS has the potential to be a powerful tool for antimicrobial resistance surveillance programs. PMID:26519386

  9. Transcriptome Profiling of Antimicrobial Resistance in Pseudomonas aeruginosa.

    Science.gov (United States)

    Khaledi, Ariane; Schniederjans, Monika; Pohl, Sarah; Rainer, Roman; Bodenhofer, Ulrich; Xia, Boyang; Klawonn, Frank; Bruchmann, Sebastian; Preusse, Matthias; Eckweiler, Denitsa; Dötsch, Andreas; Häussler, Susanne

    2016-08-01

    Emerging resistance to antimicrobials and the lack of new antibiotic drug candidates underscore the need for optimization of current diagnostics and therapies to diminish the evolution and spread of multidrug resistance. As the antibiotic resistance status of a bacterial pathogen is defined by its genome, resistance profiling by applying next-generation sequencing (NGS) technologies may in the future accomplish pathogen identification, prompt initiation of targeted individualized treatment, and the implementation of optimized infection control measures. In this study, qualitative RNA sequencing was used to identify key genetic determinants of antibiotic resistance in 135 clinical Pseudomonas aeruginosa isolates from diverse geographic and infection site origins. By applying transcriptome-wide association studies, adaptive variations associated with resistance to the antibiotic classes fluoroquinolones, aminoglycosides, and β-lactams were identified. Besides potential novel biomarkers with a direct correlation to resistance, global patterns of phenotype-associated gene expression and sequence variations were identified by predictive machine learning approaches. Our research serves to establish genotype-based molecular diagnostic tools for the identification of the current resistance profiles of bacterial pathogens and paves the way for faster diagnostics for more efficient, targeted treatment strategies to also mitigate the future potential for resistance evolution. PMID:27216077

  10. Salmonella and Campylobacter: Antimicrobial resistance and bacteriophage control in poultry.

    Science.gov (United States)

    Grant, Ar'Quette; Hashem, Fawzy; Parveen, Salina

    2016-02-01

    Salmonella and Campylobacter are major causes of foodborne related illness and are traditionally associated with consuming undercooked poultry and/or consuming products that have been cross contaminated with raw poultry. Many of the isolated Salmonella and Campylobacter that can cause disease have displayed antimicrobial resistance phenotypes. Although poultry producers have reduced on-the-farm overuse of antimicrobials, antimicrobial resistant Salmonella and Campylobacter strains still persist. One method of bio-control, that is producing promising results, is the use of lytic bacteriophages. This review will highlight the current emergence and persistence of antimicrobial resistant Salmonella and Campylobacter recovered from poultry as well as bacteriophage research interventions and limitations.

  11. Molecular cloning and characterization of novel Morus alba germin-like protein gene which encodes for a silkworm gut digestion-resistant antimicrobial protein.

    Directory of Open Access Journals (Sweden)

    Bharat Bhusan Patnaik

    Full Text Available BACKGROUND: Silkworm fecal matter is considered one of the richest sources of antimicrobial and antiviral protein (substances and such economically feasible and eco-friendly proteins acting as secondary metabolites from the insect system can be explored for their practical utility in conferring broad spectrum disease resistance against pathogenic microbial specimens. METHODOLOGY/PRINCIPAL FINDINGS: Silkworm fecal matter extracts prepared in 0.02 M phosphate buffer saline (pH 7.4, at a temperature of 60°C was subjected to 40% saturated ammonium sulphate precipitation and purified by gel-filtration chromatography (GFC. SDS-PAGE under denaturing conditions showed a single band at about 21.5 kDa. The peak fraction, thus obtained by GFC wastested for homogeneityusing C18reverse-phase high performance liquid chromatography (HPLC. The activity of the purified protein was tested against selected Gram +/- bacteria and phytopathogenic Fusarium species with concentration-dependent inhibitionrelationship. The purified bioactive protein was subjected to matrix-assisted laser desorption and ionization-time of flight mass spectrometry (MALDI-TOF-MS and N-terminal sequencing by Edman degradation towards its identification. The N-terminal first 18 amino acid sequence following the predicted signal peptide showed homology to plant germin-like proteins (Glp. In order to characterize the full-length gene sequence in detail, the partial cDNA was cloned and sequenced using degenerate primers, followed by 5'- and 3'-rapid amplification of cDNA ends (RACE-PCR. The full-length cDNA sequence composed of 630 bp encoding 209 amino acids and corresponded to germin-like proteins (Glps involved in plant development and defense. CONCLUSIONS/SIGNIFICANCE: The study reports, characterization of novel Glpbelonging to subfamily 3 from M. alba by the purification of mature active protein from silkworm fecal matter. The N-terminal amino acid sequence of the purified protein was

  12. Proteomics as the final step in the functional metagenomics study of antimicrobial resistance

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    Fiona eFouhy

    2015-03-01

    Full Text Available The majority of clinically applied antimicrobial agents are derived from natural products generated by soil microorganisms and therefore resistance is likely to be ubiquitous in such environments. This is supported by the fact that numerous clinically important resistance mechanisms are encoded within the chromosomes of such bacteria. Advances in genomic sequencing have enabled the in silico identification of putative resistance genes present in these microorganisms. However, it is not sufficient to rely on the identification of putative resistance genes, we must also determine if the resultant proteins confer a resistant phenotype. This will require an analysis pipeline that extends from the extraction of environmental DNA, to the identification and analysis of potential resistance genes and their resultant proteins and phenotypes. This review focuses on the application of functional metagenomics and proteomics to study antimicrobial resistance in diverse environments.

  13. Antimicrobial resistance genes in multidrug-resistant Salmonella enterica isolated from animals, retail meats, and humans in the United States and Canada

    Science.gov (United States)

    Salmonella enterica is a prevalent foodborne pathogen which can carry multi-drug resistance (MDR) and pose a threat to human health. Identifying the genetic elements associated with MDR in Salmonella isolated from animals, foods, and humans can help determine the sources of MDR in food animals and t...

  14. Antimicrobial-resistant enterococci in animals and meat: a human health hazard?

    Science.gov (United States)

    Hammerum, Anette M; Lester, Camilla H; Heuer, Ole E

    2010-10-01

    Enterococcus faecium and Enterococcus faecalis belong to the gastrointestinal flora of humans and animals. Although normally regarded harmless commensals, enterococci may cause a range of different infections in humans, including urinary tract infections, sepsis, and endocarditis. The use of avoparcin, gentamicin, and virginiamycin for growth promotion and therapy in food animals has lead to the emergence of vancomycin- and gentamicin-resistant enterococci and quinupristin/dalfopristin-resistant E. faecium in animals and meat. This implies a potential risk for transfer of resistance genes or resistant bacteria from food animals to humans. The genes encoding resistance to vancomycin, gentamicin, and quinupristin/dalfopristin have been found in E. faecium of human and animal origin; meanwhile, certain clones of E. faecium are found more frequently in samples from human patients, while other clones predominate in certain animal species. This may suggest that antimicrobial-resistant E. faecium from animals could be regarded less hazardous to humans; however, due to their excellent ability to acquire and transfer resistance genes, E. faecium of animal origin may act as donors of antimicrobial resistance genes for other more virulent enterococci. For E. faecalis, the situation appears different, as similar clones of, for example, vancomycin- and gentamicin-resistant E. faecalis have been obtained from animals and from human patients. Continuous surveillance of antimicrobial resistance in enterococci from humans and animals is essential to follow trends and detect emerging resistance. PMID:20578915

  15. An economic perspective on policy to reduce antimicrobial resistance.

    Science.gov (United States)

    Coast, J; Smith, R D; Millar, M R

    1998-01-01

    Resistance to antimicrobial drugs is increasing worldwide. This resistance is, at least in part, associated with high antimicrobial usage. Despite increasing awareness, economists (and policy analysts more generally) have paid little attention to the problem. In this paper antimicrobial resistance is conceptualised as a negative externality associated with the consumption of antimicrobials and is set within the broader context of the costs and benefits associated with antimicrobial usage. It is difficult to determine the overall impact of attempting to reduce resistance, given the extremely limited ability to model the epidemiology of resistant and sensitive micro-organisms. It is assumed for the purposes of the paper, however, that dealing with resistance by reducting antimicrobial usage would lead to a positive societal benefit. Three policy options traditionally associated with environmental economics (regulation, permits and charges) are examined in relation to their potential ability to impact upon the problem of resistance. The primary care sector of the U.K.'s National Health Service provides the context for this examination. Simple application of these policies to health care is likely to be problematic, with difficulties resulting particularly from the potential reduction in clinical freedom to prescribe when appropriate, and from the desire for equity in health care provision. The paper tentatively concludes that permits could offer the best policy response to antimicrobial resistance, with the caveat that empirical research is needed to develop the most practical and efficient system. This research must be conducted alongside the required epidemiological research.

  16. Antimicrobial resistance of Listeria monocytogenes and Listeria innocua from meat products and meat-processing environment.

    Science.gov (United States)

    Gómez, Diego; Azón, Ester; Marco, Noelia; Carramiñana, Juan J; Rota, Carmina; Ariño, Agustín; Yangüela, Javier

    2014-09-01

    A total of 336 Listeria isolates from ready-to-eat (RTE) meat products and meat-processing environments, consisting of 206 Listeria monocytogenes, and 130 Listeria innocua isolates, were characterized by disc diffusion assay and minimum inhibitory concentration (MIC) values for antimicrobial susceptibility against twenty antimicrobials. Resistance to one or two antimicrobials was observed in 71 L. monocytogenes isolates (34.5%), and 56 L. innocua isolates (43.1%). Multidrug resistance was identified in 24 Listeria isolates, 18 belonging to L. innocua (13.9%) and 6 to L. monocytogenes (2.9%). Oxacillin resistance was the most common resistance phenotype and was identified in 100% Listeria isolates. A medium prevalence of resistance to clindamycin (39.3% isolates) and low incidence of resistance to tetracycline (3.9% isolates) were also detected. Listeria isolates from RTE meat products displayed higher overall antimicrobial resistance (31.3%) than those from the environment (13.4%). All the strains assayed were sensitive to the preferred antibiotics used to treat listeriosis. Results showed that although antimicrobial resistance in L. monocytogenes still occurs at a low prevalence, L. innocua can form a reservoir of resistance genes which may transfer between bacterial species, including transference to organisms capable of causing disease in humans.

  17. Prevalence, Antimicrobial Resistance, and Genotypic Characterization of Vancomycin-Resistant Enterococci in Meat Preparations.

    Science.gov (United States)

    Guerrero-Ramos, Emilia; Molina-González, Diana; Blanco-Morán, Sonia; Igrejas, Gilberto; Poeta, Patrícia; Alonso-Calleja, Carlos; Capita, Rosa

    2016-05-01

    A total of 160 samples of poultry (80), pork (40), and beef (40) preparations (red sausages, white sausages, hamburgers, meatballs, nuggets, minced meat, escalope, and crepes) were tested in northwestern Spain to determine the prevalence of vancomycin-resistant enterococci (VRE). VRE were detected in 38 (23.8%) samples (37.5% of poultry, 15.0% of pork, and 5.0% of beef samples). One strain per food sample was further characterized. Isolates were identified as Enterococcus faecium (14 strains), E. durans (10), E. hirae (7), E. gallinarum (5), and E. casseliflavus-E. flavescens (2). All strains showed resistance or intermediate susceptibility to three or more antimicrobials of clinical significance, in addition to vancomycin. High rates of resistance or intermediate susceptibility were observed for teicoplanin (81.6% of isolates), chloramphenicol (81.6%), erythromycin (100%), quinupristin-dalfopristin (89.5%), and ciprofloxacin (81.6%). A moderate rate of resistance or intermediate susceptibility emerged for ampicillin (34.2%) and tetracycline (36.8%). Genes encoding antimicrobial resistance and virulence were studied by PCR. The vanA, vanB, vanC-1, and vanC-2/3 genes were identified in 27, 1, 5, and 2 isolates, respectively. Other resistance genes or transposon sequences found were tet(L), tet(M), Tn5397 (tetracycline), erm(A), erm(B) (erythromycin), vat(D), and vat(E) (quinupristin-dalfopristin). Most isolates were free of virulence determinants (agg, hyl, and efaAfm genes were detected in one, one, and five strains, respectively). Strains were classified as not biofilm producers (crystal violet assay; 4 isolates) or weak biofilm producers (34 isolates). Cluster analysis (EcoRI ribotyping) suggested a strong genetic relationship among isolates from different types of meat preparations, animal species, and retail outlets. Meat preparations might play a role in the spread through the food chain of VRE with several resistance and virulence genes.

  18. Prevalence, Antimicrobial Resistance, and Genotypic Characterization of Vancomycin-Resistant Enterococci in Meat Preparations.

    Science.gov (United States)

    Guerrero-Ramos, Emilia; Molina-González, Diana; Blanco-Morán, Sonia; Igrejas, Gilberto; Poeta, Patrícia; Alonso-Calleja, Carlos; Capita, Rosa

    2016-05-01

    A total of 160 samples of poultry (80), pork (40), and beef (40) preparations (red sausages, white sausages, hamburgers, meatballs, nuggets, minced meat, escalope, and crepes) were tested in northwestern Spain to determine the prevalence of vancomycin-resistant enterococci (VRE). VRE were detected in 38 (23.8%) samples (37.5% of poultry, 15.0% of pork, and 5.0% of beef samples). One strain per food sample was further characterized. Isolates were identified as Enterococcus faecium (14 strains), E. durans (10), E. hirae (7), E. gallinarum (5), and E. casseliflavus-E. flavescens (2). All strains showed resistance or intermediate susceptibility to three or more antimicrobials of clinical significance, in addition to vancomycin. High rates of resistance or intermediate susceptibility were observed for teicoplanin (81.6% of isolates), chloramphenicol (81.6%), erythromycin (100%), quinupristin-dalfopristin (89.5%), and ciprofloxacin (81.6%). A moderate rate of resistance or intermediate susceptibility emerged for ampicillin (34.2%) and tetracycline (36.8%). Genes encoding antimicrobial resistance and virulence were studied by PCR. The vanA, vanB, vanC-1, and vanC-2/3 genes were identified in 27, 1, 5, and 2 isolates, respectively. Other resistance genes or transposon sequences found were tet(L), tet(M), Tn5397 (tetracycline), erm(A), erm(B) (erythromycin), vat(D), and vat(E) (quinupristin-dalfopristin). Most isolates were free of virulence determinants (agg, hyl, and efaAfm genes were detected in one, one, and five strains, respectively). Strains were classified as not biofilm producers (crystal violet assay; 4 isolates) or weak biofilm producers (34 isolates). Cluster analysis (EcoRI ribotyping) suggested a strong genetic relationship among isolates from different types of meat preparations, animal species, and retail outlets. Meat preparations might play a role in the spread through the food chain of VRE with several resistance and virulence genes. PMID:27296421

  19. Evaluation of feeding distiller's grains, containing virginiamycin, on antimicrobial susceptibilities in fecal isolates of Enterococcus and Escherichia coli and prevalence of resistance genes in cattle

    Science.gov (United States)

    Dried distiller’s grains (DG), produced from fermentations using no antibiotic (Control) or dosed with 2 or 20 ppm virginiamycin product and containing 0, 0.7, and 8.9 ppm virginiamycin, respectively, were fed to cattle and effects on antibiotic sensitivity and prevalence of resistance genes in comm...

  20. Molecular genetic analysis of a locus required for resistance to antimicrobial peptides in Salmonella typhimurium.

    OpenAIRE

    Parra-Lopez, C; Baer, M. T.; Groisman, E A

    1993-01-01

    The innate immunity of vertebrates and invertebrates to microbial infection is mediated in part by small cationic peptides with antimicrobial activity. Successful pathogens have evolved mechanisms to withstand the antibiotic activity of these molecules. We have isolated a set of genes from Salmonella typhimurium which are required for virulence and resistance to the antimicrobial peptides melittin and protamine. Sequence analysis of a 5.7 kb segment from the wild-type plasmid conferring resis...

  1. In vitro antimicrobial activity of linezolid tested against vancomycin-resistant enterococci isolated in Brazilian hospitals

    OpenAIRE

    Reis Adriana O.; Cordeiro Julio C. R.; Machado Antonia M.O.; Sader Helio S.

    2001-01-01

    The emergence of vancomycin-resistant enterococci (VRE) has been described recently in Brazil. This is in contrast to the USA and Europe, where the VRE appeared in the late 1980s. The progressive increase in VRE isolation poses important problems in the antimicrobial therapy of nosocomial infections. Treatment options and effective antimicrobial agents for VRE are often limited and the possibility of transfer of vancomycin genes to other Gram-positive microorganisms continues. In the search f...

  2. Antimicrobial resistance in commensal Escherichia coli in veal calves is associated with antimicrobial drug use.

    Science.gov (United States)

    Bosman, A B; Wagenaar, J A; Stegeman, J A; Vernooij, J C M; Mevius, D J

    2014-09-01

    The aim of this study was to determine the association between farm management factors, including antimicrobial drug usage, and resistance in commensal Escherichia coli isolates from the faeces of white veal calves. Ninety E. coli isolates from one pooled sample per farm (n = 48) were tested for their phenotypical resistance against amoxicillin, tetracycline, cefotaxime, ciprofloxacin and trimethoprim/sulfamethoxazole (TMP/SMX). Logistic regression analysis revealed the following risk factors (P 40 ADD/pc, tetracyclines (tetracycline, OR 13·1; amoxicillin, OR 6·5). In this study antimicrobial resistance in commensal E. coli was mainly associated with antimicrobial drug use. PMID:24152540

  3. Antimicrobial resistance-a threat to the world's sustainable development.

    Science.gov (United States)

    Jasovský, Dušan; Littmann, Jasper; Zorzet, Anna; Cars, Otto

    2016-08-01

    This commentary examines how specific sustainable development goals (SDGs) are affected by antimicrobial resistance and suggests how the issue can be better integrated into international policy processes. Moving beyond the importance of effective antibiotics for the treatment of acute infections and health care generally, we discuss how antimicrobial resistance also impacts on environmental, social, and economic targets in the SDG framework. The paper stresses the need for greater international collaboration and accountability distribution, and suggests steps towards a broader engagement of countries and United Nations agencies to foster global intersectoral action on antimicrobial resistance. PMID:27416324

  4. Antimicrobial resistance-a threat to the world's sustainable development.

    Science.gov (United States)

    Jasovský, Dušan; Littmann, Jasper; Zorzet, Anna; Cars, Otto

    2016-08-01

    This commentary examines how specific sustainable development goals (SDGs) are affected by antimicrobial resistance and suggests how the issue can be better integrated into international policy processes. Moving beyond the importance of effective antibiotics for the treatment of acute infections and health care generally, we discuss how antimicrobial resistance also impacts on environmental, social, and economic targets in the SDG framework. The paper stresses the need for greater international collaboration and accountability distribution, and suggests steps towards a broader engagement of countries and United Nations agencies to foster global intersectoral action on antimicrobial resistance.

  5. Monitoring of antimicrobial resistance among food animals: Principles and limitations

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller

    2004-01-01

    Large amounts of antimicrobial agents are in the production of food animals used for therapy and prophylactics of bacterial infections and in feed to promote growth. The use of antimicrobial agents causes problems in the therapy of infections through the selection for resistance among bacteria...... pathogenic for animals or humans. Current knowledge regarding the occurrence of antimicrobial resistance in food animals, the quantitative impact of the use of different antimicrobial agents on selection for resistance and the most appropriate treatment regimes to limit the development of resistance...... is incomplete. Programmes monitoring the occurrence and development of resistance are essential to determine the most important areas for intervention and to monitor the effects of interventions. When designing a monitoring programme it is important to decide on the purpose of the programme. Thus...

  6. Usage of antimicrobials and occurrence of antimicrobial resistance among bacteria from mink

    DEFF Research Database (Denmark)

    Pedersen, Karl; Hammer, Anne Sofie; Sørensen, Charlotte Mark;

    2009-01-01

    The usage of antimicrobials for treatment of mink and the occurrence of antimicrobial resistance among the most important bacterial pathogens in mink was investigated. The aim of the study was to provide data, which may serve as a basis for the formulation of recommendations for prudent Use...

  7. Antimicrobial resistance in equine faecal Escherichia coli isolates from North West England

    Directory of Open Access Journals (Sweden)

    Williams Nicola J

    2010-04-01

    Full Text Available Abstract Background Escherichia coli isolates of equine faecal origin were investigated for antibiotic resistance, resistance genes and their ability to perform horizontal transfer. Methods In total, 264 faecal samples were collected from 138 horses in hospital and community livery premises in northwest England, yielding 296 resistant E. coli isolates. Isolates were tested for susceptibility to antimicrobial drugs by disc diffusion and agar dilution methods in order to determine minimum inhibitory concentrations (MIC. PCR amplification was used to detect genes conferring resistance to: ampicillin (TEM and SHV beta-lactamase, chloramphenicol (catI, catII, catIII and cml, tetracycline (tetA, tetB, tetC, tetD, tet E and tetG, and trimethoprim (dfrA1, dfrA9, dfrA12, dfrA13, dfr7, and dfr17. Results The proportion of antibiotic resistant isolates, and multidrug resistant isolates (MDR was significantly higher in hospital samples compared to livery samples (MDR: 48% of hospital isolates; 12% of livery isolates, p dfr, TEM beta-lactamase, tet and cat, conferring resistance to trimethoprim, ampicillin, tetracycline and chloramphenicol, respectively. Within each antimicrobial resistance group, these genes occurred at frequencies of 93% (260/279, 91%, 86.8% and 73.5%, respectively; with 115/296 (38.8% found to be MDR isolates. Conjugation experiments were performed on selected isolates and MDR phenotypes were readily transferred. Conclusions Our findings demonstrate that E. coli of equine faecal origin are commonly resistant to antibiotics used in human and veterinary medicine. Furthermore, our results suggest that most antibiotic resistance observed in equine E. coli is encoded by well-known and well-characterized resistant genes common to E. coli from man and domestic animals. These data support the ongoing concern about antimicrobial resistance, MDR, antimicrobial use in veterinary medicine and the zoonotic risk that horses could potentially pose to

  8. Proteomics as the final step in the functional metagenomics study of antimicrobial resistance

    OpenAIRE

    Fouhy, Fiona; Stanton, Catherine; Cotter, Paul D.; Hill, Colin; Walsh, Fiona

    2015-01-01

    The majority of clinically applied antimicrobial agents are derived from natural products generated by soil microorganisms and therefore resistance is likely to be ubiquitous in such environments. This is supported by the fact that numerous clinically important resistance mechanisms are encoded within the genomes of such bacteria. Advances in genomic sequencing have enabled the in silico identification of putative resistance genes present in these microorganisms. However, it is not sufficient...

  9. Studies on Antimicrobial Resistance Transfer In vitro and Existent Selectivity of Avian Antimicrobial-Resistant Enterobacteriaccae In vivo

    Institute of Scientific and Technical Information of China (English)

    SONG Li; NING Yi-bao; ZHANG Qi-jing; YANG Cheng-huai; GAO Guang; HAN Jian-feng

    2008-01-01

    Increasing antimicrobial resistance (AR) has become a severe problem of public health in the world, whereas control of the AR of bacteria will be based on investigation of the AR mechanism. Furthermore, understanding the existent selectivity of AR organisms from animals can prevent the emergence and diffusion of AR effectively. PCR amplifications of gyrA and parC genes have been performed for detecting fluoroquinolones-resistance (FR) genes. A conjugational transfer test has been carried out using a donor which is resistant to tetracycline (TE), ampicillin (AMP), sulfamethoxazole-trimethoprim (SXT), and a recipient which is sensitive to TE, AMP, and SXT. The AR strains have been passed 20 passages. Two groups of chicken inoculated multi-AR Escherichia coli (E. Coli) and multi-AR Salmonella, respectively, are mix-fed. The result shows that amino acid codons of Ser-83 and Asp-87 are mutations from gyrA and there are no mutations from parCgenes in all the FR strains. Resistance to TE, AM, and SXT can transfer among E. Coli and the conjugal transfer frequency of TE is 3 × 10-7. AR can inherit in 20 passages at least. The multi-AR E. Coli and Salmonella can be isolated from all chickens three days after inoculation but CIP-resistant strains decrease during the time run out and disappear at 23 days after inoculation. The results indicate that the mutations of gene gyrA are correlative with the FR phenotype. AR genes that are not connected to the chromosome can transfer horizontally and vertically. AR bacteria can diffuse quickly and eliminate naturally from the host if the chicken is not under the pressure of this antibiotic.

  10. The prevalence of antimicrobial resistance and carriage of virulence genes in Staphylococcus aureus isolated from food handlers in Kuwait City restaurants

    Directory of Open Access Journals (Sweden)

    Al-Mufti Siham

    2009-06-01

    Full Text Available Abstract Background Staphylococcus aureus is a major cause of food poisoning due to their ability to produce enterotoxins which if ingested in sufficient amounts results in sickness. Food handlers carrying enterotoxin-producing S. aureus in their noses or hands can contaminate food leading to food poisoning. We characterized 200 S. aureus obtained from food handlers in different restaurants for antibacterial resistance and the carriage of virulence genes. Findings Susceptibility to antibacterial agents was determined by disk diffusion and Etest. PCR was used to detect genes for accessory gene regulator (agr; capsular polysaccharide (cap 5 and 8, staphylococcal enterotoxins (SE, toxic shock syndrome toxin-1 (TSST-1 and Panton-Valentine leukocidin (PVL. Isolates were typed using pulsed-field gel electrophoresis. In total 185 (92.5% of the 200 isolates expressed resistance to antibacterial agents. They were resistant to penicillin G (82.0%, tetracycline (19.0%, erythromycin (2.5%, clindamycin (2.0%, trimethoprim (7.5%, kanamycin (2.5%, streptomycin (1.5%, ciprofloxacin (1.5%, fusidic acid (1.0% and cadmium acetate (68.0%. Seventy-six (38.0% and 114 (57.0% isolates had type 5 and type 8 capsular polysaccharides respectively. The agr types I, II and III alleles were detected in 50.5%, 20.0% and 23.5% of the isolates respectively. They contained genes for SEI (38.5%, SEG (24.0%, SEC (23.0%, SEB (12.5%, SEH (21.5%, SEA (11.0, SED (1.5%, SEE (1.5%, TSST-1 (4.0% and PVL (9.0%. Conclusion This study revealed a high prevalence of antibacterial resistance and virulence determinants in S. aureus from food handlers in Kuwait restaurants justifying the screening of food handlers to detect and treat carriers and protect restaurant customers from staphylococcal food poisoning.

  11. Molecular Characterization and Antimicrobial Resistance Profile of Methicillin-Resistant Staphylococcus aureus in Retail Chicken.

    Science.gov (United States)

    Sallam, Khalid Ibrahim; Abd-Elghany, Samir Mohammed; Elhadidy, Mohamed; Tamura, Tomohiro

    2015-10-01

    The emergence of livestock-associated methicillin-resistant Staphylococcus aureus (MRSA) in food-producing animals is of increasing interest, raising questions about the presence of MRSA in food of animal origin and potential sources of transmission to humans via the food chain. In this study, the prevalence, molecular characterization, virulence factors, and antimicrobial susceptibility patterns of MRSA isolates from 200 retail raw chicken samples in Egypt were determined. MRSA was detected by positive amplification of the mecA gene in 38% (76 of 200) of chicken samples analyzed. This represents a potential public health threat in Egypt, as this contamination rate seems to be the highest among other studies reported worldwide. Furthermore, genes encoding α-hemolysin (hla) and staphylococcal enterotoxins (sea, seb, and sec) were detected in all of the 288 MRSA isolates. Nonetheless, none of the strains tested carried tst, the gene encoding toxic shock syndrome toxin 1. Antimicrobial resistance of MRSA isolates was most frequently detected against penicillin (93.4%), ampicillin (88.9%), and cloxacillin (83.3%). These results suggest that retail chicken might be a significant potential source for transmission of multidrug-resistant and toxigenic S. aureus in Egypt. This underlines the need for stricter hygienic measures in chicken production in Egypt to minimize the risk of transmission of these strains to consumers. To the best of our knowledge, this is the first study that reports the isolation and molecular characterization of MRSA in retail chicken samples in Egypt.

  12. Mechanisms of antimicrobial resistance in finfish aquaculture environments

    Directory of Open Access Journals (Sweden)

    Claudio D. Miranda

    2013-08-01

    Full Text Available Consumer demand for affordable fish drives the ever-growing global aquaculture industry. The intensification and expansion of culture conditions in the production of several finfish species has been coupled with an increase in bacterial fish disease and the need for treatment with antimicrobials. Understanding the molecular mechanisms of antimicrobial resistance prevalent in aquaculture environments is important to design effective disease treatment strategies, to prioritize the use and registration of antimicrobials for aquaculture use, and to assess and minimize potential risks to public health. In this brief article we provide an overview of the molecular mechanisms of antimicrobial resistance mechanisms in finfish aquaculture environments and highlight specific research that should provide the basis of sound, science-based policies for the use of antimicrobials in aquaculture.

  13. Use and Misuse of Antimicrobial Drugs in Poultry and Livestock: Mechanisms of Antimicrobial Resistance

    Directory of Open Access Journals (Sweden)

    Toni Poole* and Cynthia Sheffield

    2013-07-01

    Full Text Available Food safety begins on the farm with management practices that contribute to an abundant, safe, and affordable food supply. To attain this goal antimicrobials have been used in all stages of food animal production in the United States and elsewhere around the world at one time or another. Among food–production animals antimicrobials are used for growth promotion, disease prophylaxis or disease treatment, and are generally administered to the entire flock or herd. Over many decades bacteria have become resistant to multiple antimicrobial classes in a cumulative manner. Bacteria exhibit a number of well characterized mechanisms of resistance to antimicrobials that include: 1 modification of the antimicrobial; 2 alteration of the drug target; 3 decreased access of drug to target; and 4 implementation of an alternative metabolic pathway not affected by the drug. The mechanisms of resistance are complex and depend on the type of bacterium involved (e.g. Gram–positive or Gram–negative and the class of drug. Some bacterial species have accumulated resistance to nearly all antimicrobial classes due to a combination of intrinsic and acquired processes. This has and will continue to lead to clinical failures of antimicrobial treatment in both human and animal medicine.

  14. The global threat of antimicrobial resistance: science for intervention

    Directory of Open Access Journals (Sweden)

    I. Roca

    2015-07-01

    Full Text Available In the last decade we have witnessed a dramatic increase in the proportion and absolute number of bacterial pathogens resistant to multiple antibacterial agents. Multidrug-resistant bacteria are currently considered as an emergent global disease and a major public health problem. The B-Debate meeting brought together renowned experts representing the main stakeholders (i.e. policy makers, public health authorities, regulatory agencies, pharmaceutical companies and the scientific community at large to review the global threat of antibiotic resistance and come up with a coordinated set of strategies to fight antimicrobial resistance in a multifaceted approach. We summarize the views of the B-Debate participants regarding the current situation of antimicrobial resistance in animals and the food chain, within the community and the healthcare setting as well as the role of the environment and the development of novel diagnostic and therapeutic strategies, providing expert recommendations to tackle the global threat of antimicrobial resistance.

  15. Antimicrobial drug resistance ofStaphylococcus aureus in dairy products

    Institute of Scientific and Technical Information of China (English)

    Sasidharan S; Prema B; Yoga Latha L

    2011-01-01

    Objective:To evaluate the prevalence of multidrug resistantStaphylococcus aureus(S. aureus) in dairy products.Methods:Isolation and identification ofS. aureus were performed in3 dairy-based food products. The isolates were tested for their susceptibility to5 different common antimicrobial drugs.Results:Of50 samples examined,5 (10%) were contaminated with S. aureus. Subsequently, the5 isolates were subjected to antimicrobial resistance pattern using five antibiotic discs (methicillin, vancomycin, kanamycin, chloramphenicol and tetracycline). Sample 29 showed resistance to methicillin and vancomycin. Sample18 showed intermediate response to tetracycline. The other samples were susceptible to all the antibiotics tested.Conclusions:The results provide preliminary data on sources of food contamination which may act as vehicles for the transmission of antimicrobial-resistantStaphylococcus.Therefore, it enables us to develop preventive strategies to avoid the emergence of new strains of resistantS. aureus.

  16. Prevalence and characterization of antimicrobial-resistant Escherichia coli isolated from conventional and organic vegetables.

    Science.gov (United States)

    Kim, Sara; Woo, Gun-Jo

    2014-10-01

    To compare the characteristics and to identify the epidemiological relationships of Escherichia coli isolated from organic and conventional vegetables, the antimicrobial resistance and genetic properties of E. coli were investigated from 2010 to 2011. E. coli was isolated from 1 of 111 (0.9%) organic vegetables and from 20 of 225 (8.9%) conventional vegetables. The majority of strains were isolated from the surrounding farming environment (n=27/150 vs. 49/97 in organic vs. conventional samples). The majority of the vegetable strains were isolated from the surrounding farming environments. E. coli isolated from organic vegetables showed very low antimicrobial resistance rates except for cephalothin, ranging from 0% to 17.9%, while the resistance rates to cephalothin (71%) were extremely high in both groups. E. coli isolates expressed various resistance genes, which most commonly included blaTEM, tet(A), strA, strB, and qnrS. However, none of the isolates harbored tet(D), tet(E), tet(K), tet(L), tet(M), or qnrA. The transferability of tet gene, tet(A), and tet(B) was identified in tetracycline-resistant E. coli, and the genetic relationship was confirmed in a few cases from different sources. With regard to the lower antimicrobial resistance found in organic produce, this production mode seems able to considerably reduce the selection of antimicrobial-resistant bacteria on vegetables. PMID:25140978

  17. Microarray Evaluation of Antimicrobial Resistance and Virulence of Escherichia coli Isolates from Portuguese Poultry

    Directory of Open Access Journals (Sweden)

    Nuno Mendonça

    2016-01-01

    Full Text Available The presence of antimicrobial resistance and virulence factors of 174 Escherichia coli strains isolated from healthy Portuguese Gallus gallus was evaluated. Resistance profiles were determined against 33 antimicrobials by microbroth dilution. Resistance was prevalent for tetracycline (70% and ampicillin (63%. Extended-spectrum beta-lactamase (ESBL phenotype was observed in 18% of the isolates. Multidrug resistance was found in 56% of isolates. A subset of 74 isolates were screened by DNA microarrays for the carriage of 88 antibiotic resistance genes and 62 virulence genes. Overall, 37 different resistance genes were detected. The most common were tet(A (72%, blaTEM (68%, and sul1 (47%, while 21% isolates harbored an ESBL gene (blaCTX-M group 1, group 2, or group 9. Of these, 96% carried the increased serum survival (iss virulence gene, while 89% presented the enterobactin siderophore receptor protein (iroN, 70% the temperature-sensitive hemagglutinin (tsh, and 68% the long polar fimbriae (lpfA virulence genes associated with extraintestinal pathogenic E. coli. In conclusion, prevalence of antibiotic resistant E. coli from the microbiota of Portuguese chickens was high, including to extended spectrum cephalosporins. The majority of isolates seems to have the potential to trigger extraintestinal human infection due to the presence of some virulence genes. However, the absence of genes specific for enteropathogenic E. coli reduces the risk for human intestinal infection.

  18. Zoo Animals as Reservoirs of Gram-Negative Bacteria Harboring Integrons and Antimicrobial Resistance Genes▿

    OpenAIRE

    Ahmed, Ashraf M.; Motoi, Yusuke; Sato, Maiko; Maruyama, Akito; Watanabe, Hitoshi; Fukumoto, Yukio; Shimamoto, Tadashi

    2007-01-01

    A total of 232 isolates of gram-negative bacteria were recovered from mammals, reptiles, and birds housed at Asa Zoological Park, Hiroshima prefecture, Japan. Forty-nine isolates (21.1%) showed multidrug resistance phenotypes and harbored at least one antimicrobial resistance gene. PCR and DNA sequencing identified class 1 and class 2 integrons and many β-lactamase-encoding genes, in addition to a novel AmpC β-lactamase gene, blaCMY-26. Furthermore, the plasmid-mediated quinolone resistance g...

  19. A Complete Lipopolysaccharide Inner Core Oligosaccharide Is Required for Resistance of Burkholderia cenocepacia to Antimicrobial Peptides and Bacterial Survival In Vivo

    OpenAIRE

    Loutet, Slade A.; Flannagan, Ronald S.; Kooi, Cora; Sokol, Pamela A.; Valvano, Miguel A

    2006-01-01

    Burkholderia cenocepacia is an important opportunistic pathogen of patients with cystic fibrosis. This bacterium is inherently resistant to a wide range of antimicrobial agents, including high concentrations of antimicrobial peptides. We hypothesized that the lipopolysaccharide (LPS) of B. cenocepacia is important for both virulence and resistance to antimicrobial peptides. We identified hldA and hldD genes in B. cenocepacia strain K56-2. These two genes encode enzymes involved in the modific...

  20. Associations between host characteristics and antimicrobial resistance of Salmonella typhimurium.

    Science.gov (United States)

    Ruddat, I; Tietze, E; Ziehm, D; Kreienbrock, L

    2014-10-01

    A collection of Salmonella Typhimurium isolates obtained from sporadic salmonellosis cases in humans from Lower Saxony, Germany between June 2008 and May 2010 was used to perform an exploratory risk-factor analysis on antimicrobial resistance (AMR) using comprehensive host information on sociodemographic attributes, medical history, food habits and animal contact. Multivariate resistance profiles of minimum inhibitory concentrations for 13 antimicrobial agents were analysed using a non-parametric approach with multifactorial models adjusted for phage types. Statistically significant associations were observed for consumption of antimicrobial agents, region type and three factors on egg-purchasing behaviour, indicating that besides antimicrobial use the proximity to other community members, health consciousness and other lifestyle-related attributes may play a role in the dissemination of resistances. Furthermore, a statistically significant increase in AMR from the first study year to the second year was observed.

  1. Prevalence and Antimicrobial Resistance of Enterococcus Species: A Hospital-Based Study in China

    Directory of Open Access Journals (Sweden)

    Wei Jia

    2014-03-01

    Full Text Available Objective: to investigate the prevalence and antimicrobial resistance of Enterococcus species isolated from a university hospital, and explore the mechanisms underlying the antimicrobial resistance, so as to provide clinical evidence for the inappropriate clinical use of antimicrobial agents and the control and prevention of enterococcal infections. Methods: a total of 1,157 enterococcal strains isolated from various clinical specimens from January 2010 to December 2012 in the General Hospital of Ningxia Medical University were identified to species level with a VITEK-2 COMPACT fully automated microbiological system, and the antimicrobial susceptibility of Enterococcus species was determined using the Kirby-Bauer disc diffusion method. The multiple-drug resistant enterococcal isolates were screened from the clinical isolates of Enterococcus species from the burns department. The minimal inhibitory concentration (MIC of Enterococcus species to the three fluoroquinolones, including ciprofloxacin, gatifloxacin and levofloxacin was determined with the agar dilution method, and the changes in the MIC of Enterococcus species to the three fluoroquinolones following reserpine treatment were evaluated. The β-lactam, aminoglycoside, tetracycline, macrolide, glycopeptide resistance genes and the efflux pump emeA genes were detected in the enterococcal isolates using a polymerase chain reaction (PCR assay. Results: the 1,157 clinical isolates of Enterococcus species included 679 E. faecium isolates (58.7%, 382 E. faecalis isolates (33%, 26 E. casseliflavus isolates (2.2%, 24 E. avium isolates (2.1%, and 46 isolates of other Enterococcus species (4%. The prevalence of antimicrobial resistance varied significantly between E. faecium and E. faecalis, and ≤1.1% of these two Enterococcus species were found to be resistant to vancomycin, teicoplanin or linezolid. In addition, the Enterococcus species isolated from different departments of the hospital

  2. Mechanobiology of Antimicrobial Resistant Escherichia coli and Listeria innocua.

    Science.gov (United States)

    Tajkarimi, Mehrdad; Harrison, Scott H; Hung, Albert M; Graves, Joseph L

    2016-01-01

    A majority of antibiotic-resistant bacterial infections in the United States are associated with biofilms. Nanoscale biophysical measures are increasingly revealing that adhesive and viscoelastic properties of bacteria play essential roles across multiple stages of biofilm development. Atomic Force Microscopy (AFM) applied to strains with variation in antimicrobial resistance enables new opportunities for investigating the function of adhesive forces (stickiness) in biofilm formation. AFM force spectroscopy analysis of a field strain of Listeria innocua and the strain Escherichia coli K-12 MG1655 revealed differing adhesive forces between antimicrobial resistant and nonresistant strains. Significant increases in stickiness were found at the nanonewton level for strains of Listeria innocua and Escherichia coli in association with benzalkonium chloride and silver nanoparticle resistance respectively. This advancement in the usage of AFM provides for a fast and reliable avenue for analyzing antimicrobial resistant cells and the molecular dynamics of biofilm formation as a protective mechanism.

  3. The prevalence of antimicrobial resistance in clinical isolates from Gulf Corporation Council countries

    Directory of Open Access Journals (Sweden)

    Aly Mahmoud

    2012-07-01

    Full Text Available Abstract Background The burden of antimicrobial resistance worldwide is substantial and is likely to grow. Many factors play a role in the emergence of resistance. These resistance mechanisms may be encoded on transferable genes, which facilitate the spread of resistance between bacterial strains of the same and/or different species. Other resistance mechanisms may be due to alterations in the chromosomal DNA which enables the bacteria to withstand the environment and multiply. Many, if not most, of the Gulf Corporation Council (GCC countries do not have clear guidelines for antimicrobial use, and lack policies for restricting and auditing antimicrobial prescriptions. Objective The aim of this study is to review the prevalence of antibiotic resistance in GCC countries and explore the reasons for antibiotic resistance in the region. Methodology The PubMed database was searched using the following key words: antimicrobial resistance, antibiotic stewardship, prevalence, epidemiology, mechanism of resistance, and GCC country (Saudi Arabia, Qatar, Bahrain, Kuwait, Oman, and United Arab Emirates. Results From January1990 through April 2011, there were 45 articles published reviewing antibiotic resistance in the GCC countries. Among all the GCC countries, 37,295 bacterial isolates were studied for antimicrobial resistance. The most prevalent microorganism was Escherichia coli (10,073/44%, followed by Klebsiella pneumoniae (4,709/20%, Pseudomonas aeruginosa (4,287/18.7%, MRSA (1,216/5.4%, Acinetobacter (1,061/5%, with C. difficile and Enterococcus representing less than 1%. Conclusion In the last 2 decades, E. coli followed by Klebsiella pneumoniae were the most prevalent reported microorganisms by GCC countries with resistance data.

  4. The livestock reservoir for antimicrobial resistance: a personal view on changing patterns of risks, effects of interventions and the way forward

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller

    2015-01-01

    limiting data on both use of antimicrobial agents, occurrence and spread of resistance as well as impact on human health. However, in recent years, emerging issues related to methicillin-resistant Staphylococcus aureus, Clostridium difficile, Escherichia coli and horizontally transferred genes indicates...... burden and the effect of interventions, there is a need for global harmonized integrated and continuous surveillance of antimicrobial usage and antimicrobial resistance, preferably associated with data on production and animal diseases to determine the positive and negative impact of reducing...

  5. Antimicrobial resistance of Enterococcus faecalis isolated from meat

    OpenAIRE

    Różańska Hanna; Lewtak-Piłat Aleksandra; Osek Jacek

    2015-01-01

    The aim of the study was the evaluation of the antimicrobial resistance of Enterococcus faecalis strains isolated from cattle, pig, and poultry meat. A test was performed on 111 strains using the minimum inhibitory concentration technique. The highest number of isolates (94 strains) were resistant to lincomycin, the second-highest resistance was to quinupristin/dalfopristin (88 strains), tetracycline followed (65 strains), and erythromycin resistance was also notable (40 strains). All isolate...

  6. Oral administration of antimicrobials increase antimicrobial resistance in E. coli from chicken--a systematic review.

    Science.gov (United States)

    Simoneit, C; Burow, E; Tenhagen, B-A; Käsbohrer, A

    2015-01-01

    Antimicrobials play an important role in animal and human health care. It was the aim of this systematic review to assess the effects of oral administration of antimicrobials on the development of antimicrobial resistance (AMR) in Escherichia coli (E. coli) from chickens. Moreover, the effects of the administration of more than one antimicrobial and of different dosages were studied. Literature was searched in November 2012 from the electronic databases ISI Web of Science, PubMed, Scopus and a national literature database (DIMDI) as well as the database ProQuest LLC. The search was updated in March 2014. Original studies describing a treatment (A) and a control group of either non-treatment (C) or initial value (0) and determining AMR in E. coli at different sample points (SP) were included. The literature search resulted in 35 full text articles on the topic, seven (20%) of which contained sufficient information on the administered antimicrobial and the impact of treatment on AMR. Most papers described the use of more than one antimicrobial, several dosages, controls (non-treatment or pre-treatment) and measured AMR at different SPs leading to a total of 227 SPs on the impact of the use of antimicrobials on AMR in chickens. 74% of the SPs (168/227) described a higher AMR-rate in E. coli from treated animals than from controls. After the administration of a single antimicrobial, AMR increased at 72% of the SPs. Administration of more than one antimicrobial increased AMR at 82% of the SPs. Higher dosages were associated with similar or higher AMR rates. The limited number of studies for each antimicrobial agent and the high variability in the resistance effect call for more well designed studies on the impact of oral administration on AMR development and spread. PMID:25433717

  7. Bacterial flora and antimicrobial resistance in raw frozen cultured seafood imported to Denmark.

    Science.gov (United States)

    Noor Uddin, Gazi M; Larsen, Marianne Halberg; Guardabassi, Luca; Dalsgaard, Anders

    2013-03-01

    Intensified aquaculture includes the use of antimicrobials for disease control. In contrast to the situation in livestock, Escherichia coli and enterococci are not part of the normal gastrointestinal flora of fish and shrimp and therefore not suitable indicators of antimicrobial resistance in seafood. In this study, the diversity and phenotypic characteristics of the bacterial flora in raw frozen cultured and wild-caught shrimp and fish were evaluated to identify potential indicators of antimicrobial resistance. The bacterial flora cultured on various agar media at different temperatures yielded total viable counts of 4.0 × 10(4) to 3.0 × 10(5) CFU g(-1). Bacterial diversity was indicated by 16S rRNA sequence analysis of 84 isolates representing different colony types; 24 genera and 51 species were identified. Pseudomonas spp. (23% of isolates), Psychrobacter spp. (17%), Serratia spp. (13%), Exiguobacterium spp. (7%), Staphylococcus spp. (6%), and Micrococcus spp. (6%) dominated. Disk susceptibility testing of 39 bacterial isolates to 11 antimicrobials revealed resistance to ampicillin, amoxicillin-clavulanic acid, erythromycin, and third generation cephalosporins. Resistance to third generation cephalosporins was found in Pseudomonas, a genus naturally resistant to most β-lactam antibiotics, and in Staphylococcus hominis. Half of the isolates were susceptible to all antimicrobials tested. Results indicate that identification of a single bacterial resistance indicator naturally present in seafood at point of harvest is unlikely. The bacterial flora found likely represents a processing rather than a raw fish flora because of repeated exposure of raw material to water during processing. Methods and appropriate indicators, such as quantitative PCR of resistance genes, are needed to determine how antimicrobials used in aquaculture affect resistance of bacteria in retailed products.

  8. Salmonella enterica in imported and domestic day-old turkey poults in Egypt: repertoire of virulence genes and their antimicrobial resistance profiles.

    Science.gov (United States)

    Osman, K M; Marouf, S H; Erfan, A M; AlAtfeehy, N

    2014-12-01

    Globalisation and international trade facilitate the rapid spread and transmission of foodborne pathogens. This study was designed to determine the serovars, distribution of virulence genes (invA, avrA, ssaQ, mgtC, siiD, sopB, gipA, sodC1, sopE1, spvC, bcfC) and antibiotic resistance profiles in salmonellae recovered from imported and domestic day-old turkey poults in Egypt. The prevalence of salmonellae in the imported poults was 4% (6/150): S. Enteritidis was the most frequent isolate (1.3%; 2/150), followed by Typhimurium, Virchow, Larochelle and a non-typeable strain, each with 0.7% (1/150) prevalence. The prevalence of salmonellae in the domestic poults was invA, sopB and bcfC were detected in all the Enteritidis, Typhimurium, Virchow, Larochelle, Altona and non-typeable isolates (100%); the gene gipA was absent from all isolates. Carriage of invA, sopB and bcfC among the Enteritidis, Typhimurium, Virchow, Larochelle, Altona and non-typeable isolates was associated with a core pattern of resistance to three antibiotics: streptomycin, nalidixic acid and chloramphenicol. The detection of S. Enteritidis, Typhimurium, Virchow, Larochelle, and Altona in turkey poults has important implications because these serovars are a significant cause of foodborne illness and enteric fever in humans.

  9. Molecular epidemiology and antimicrobial resistance of methicillin-resistant Staphylococcus aureus bloodstream isolates in Taiwan, 2010.

    Directory of Open Access Journals (Sweden)

    Chih-Jung Chen

    Full Text Available The information of molecular characteristics and antimicrobial susceptibility pattern of methicillin-resistant Staphylococcus aureus (MRSA is essential for control and treatment of diseases caused by this medically important pathogen. A total of 577 clinical MRSA bloodstream isolates from six major hospitals in Taiwan were determined for molecular types, carriage of Panton-Valentine leukocidin (PVL and sasX genes and susceptibilities to 9 non-beta-lactam antimicrobial agents. A total of 17 genotypes were identified in 577 strains by pulsotyping. Five major pulsotypes, which included type A (26.2%, belonging to sequence type (ST 239, carrying type III staphylococcal chromosomal cassette mec (SCCmec, type F (18.9%, ST5-SCCmecII, type C (18.5%, ST59-SCCmecIV, type B (12.0%, ST239-SCCmecIII and type D (10.9%, ST59-SCCmecVT/IV, prevailed in each of the six sampled hospitals. PVL and sasX genes were respectively carried by ST59-type D strains and ST239 strains with high frequencies (93.7% and 99.1%, respectively but rarely detected in strains of other genotypes. Isolates of different genotypes and from different hospitals exhibited distinct antibiograms. Multi-resistance to ≥3 non-beta-lactams was more common in ST239 isolates (100% than in ST5 isolates (97.2%, P = 0.0347 and ST59 isolates (8.2%, P<0.0001. Multivariate analysis further indicated that the genotype, but not the hospital, was an independent factor associated with muti-resistance of the MRSA strains. In conclusion, five common MRSA clones with distinct antibiograms prevailed in the major hospitals in Taiwan in 2010. The antimicrobial susceptibility pattern of invasive MRSA was mainly determined by the clonal distribution.

  10. Mycoplasma bovis: Mechanisms of Resistance and Trends in Antimicrobial Susceptibility

    Science.gov (United States)

    Lysnyansky, Inna; Ayling, Roger D.

    2016-01-01

    Mycoplasma bovis is a cell-wall-less bacterium and belongs to the class Mollicutes. It is the most important etiological agent of bovine mycoplasmoses in North America and Europe, causing respiratory disease, mastitis, otitis media, arthritis, and reproductive disease. Clinical disease associated with M. bovis is often chronic, debilitating, and poorly responsive to antimicrobial therapy, resulting in significant economic loss, the full extent of which is difficult to estimate. Until M. bovis vaccines are universally available, sanitary control measures and antimicrobial treatment are the only approaches that can be used in attempts to control M. bovis infections. However, in vitro studies show that many of the current M. bovis isolates circulating in Europe have high minimum inhibitory concentrations (MIC) for many of the commercially available antimicrobials. In this review we summarize the current MIC trends indicating the development of antimicrobial resistance in M. bovis as well as the known molecular mechanisms by which resistance is acquired. PMID:27199926

  11. Salmonella enterica in imported and domestic day-old turkey poults in Egypt: repertoire of virulence genes and their antimicrobial resistance profiles.

    Science.gov (United States)

    Osman, K M; Marouf, S H; Erfan, A M; AlAtfeehy, N

    2014-12-01

    Globalisation and international trade facilitate the rapid spread and transmission of foodborne pathogens. This study was designed to determine the serovars, distribution of virulence genes (invA, avrA, ssaQ, mgtC, siiD, sopB, gipA, sodC1, sopE1, spvC, bcfC) and antibiotic resistance profiles in salmonellae recovered from imported and domestic day-old turkey poults in Egypt. The prevalence of salmonellae in the imported poults was 4% (6/150): S. Enteritidis was the most frequent isolate (1.3%; 2/150), followed by Typhimurium, Virchow, Larochelle and a non-typeable strain, each with 0.7% (1/150) prevalence. The prevalence of salmonellae in the domestic poults was < 2% (2/150) and serotyping indicated a prevalence of 1.3% (1/150) for both Typhimurium and Altona. In polymerase chain reaction screening, the genes invA, sopB and bcfC were detected in all the Enteritidis, Typhimurium, Virchow, Larochelle, Altona and non-typeable isolates (100%); the gene gipA was absent from all isolates. Carriage of invA, sopB and bcfC among the Enteritidis, Typhimurium, Virchow, Larochelle, Altona and non-typeable isolates was associated with a core pattern of resistance to three antibiotics: streptomycin, nalidixic acid and chloramphenicol. The detection of S. Enteritidis, Typhimurium, Virchow, Larochelle, and Altona in turkey poults has important implications because these serovars are a significant cause of foodborne illness and enteric fever in humans. PMID:25812224

  12. Human health risks associated with antimicrobial-resistant enterococci and Staphylococcus aureus on poultry meat.

    Science.gov (United States)

    Bortolaia, V; Espinosa-Gongora, C; Guardabassi, L

    2016-02-01

    Enterococci and staphylococci are frequent contaminants on poultry meat. Enterococcus faecalis, Enterococcus faecium and Staphylococcus aureus are also well-known aetiological agents of a wide variety of infections resulting in major healthcare costs. This review provides an overview of the human health risks associated with the occurrence of these opportunistic human pathogens on poultry meat with particular focus on the risk of food-borne transmission of antimicrobial resistance. In the absence of conclusive evidence of transmission, this risk was inferred using data from scientific articles and national reports on prevalence, bacterial load, antimicrobial resistance and clonal distribution of these three species on poultry meat. The risks associated with ingestion of antimicrobial-resistant enterococci of poultry origin comprise horizontal transfer of resistance genes and transmission of multidrug-resistant E. faecalis lineages such as sequence type ST16. Enterococcus faecium lineages occurring in poultry meat products are distantly related to those causing hospital-acquired infections but may act as donors of quinupristin/dalfopristin resistance and other resistance determinants of clinical interest to the human gut microbiota. Ingestion of poultry meat contaminated with S. aureus may lead to food poisoning. However, antimicrobial resistance in the toxin-producing strains does not have clinical implications because food poisoning is not managed by antimicrobial therapy. Recently methicillin-resistant S. aureus of livestock origin has been reported on poultry meat. In theory handling or ingestion of contaminated meat is a potential risk factor for colonization by methicillin-resistant S. aureus. However, this risk is presently regarded as negligible by public health authorities. PMID:26706616

  13. EMERGING ANTIMICROBIAL RESISTANCE IN HOSPITAL A THREAT TO PUBLIC HEALTH

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    Vichal Rastogi

    2013-01-01

    Full Text Available Background: Antimicrobial resistance(AMR threatens the health of many throughout the world, since both old and new infectious diseases remain a formidable public health threat. When pathogenic microorganisms can multiply beyond some critical mass in the face of invading antimicrobials, treatment outcome is compromised. This phenomenon is referred as antimicrobial resistance (AMR. Objective: This retrospective study was conducted to assess the overall antimicrobial resistance in bacterial isolates from tertiary care hospitals as majority of patients here receive empirical antibiotics therapy. Method: This retrospective study was carried out in teaching hospital, Greater Noida to determine prevalence of multidrug resistance in patients in relation to empirical antibiotic therapy in hospital. Various samples (pus,urine,blood were collected for bacterial culture and antibiotic sensitivity. Results: Total 500 bacterial strains isolated from ICU, surgery, obstetrics & gynaecology and orthopaedics and their sensitivity pattern was compared in this study. The highest number of resistant bacterias were of pseudomonas sp. i.e. 21(33.87% followed by 16(25.80% of staphylococcus aureus, 12(19.35% of Escherichia coli, Klebseilla sp & Proteus vulgaris were 05(8.06% each & Citrobacter sp. 03(4.83%. Total 62(12.4% bacterial isolates were found to be resistant to multiple drugs. The 31 (50% of these resistant bacteria were prevalent in ICU, 12(19.35% in Surgery, 11(17.74% in Gynaecology, 08(12.90% in Orthopaedics.. All the bacterial strains were resistant to common antibiotics like Penicillin, Amoxicillin, Doxycycline & Cotrimoxazole and some were even resistant to Imipenem. Conclusion: Therefore we have outlined the nature of the antimicrobial resistance problem as an important health issue for national and international community. It is advised to avoid use of empirical antibiotics therapy.

  14. Identification and Antimicrobial Resistance of Bacteria Isolated from Probiotic Products Used in Shrimp Culture

    DEFF Research Database (Denmark)

    Noor Uddin, Gazi Md; Larsen, Marianne Halberg; Christensen, Henrik;

    2015-01-01

    Probiotics are increasingly used in aquaculture to control diseases and improve feed digestion and pond water quality; however, little is known about the antimicrobial resistance properties of such probiotic bacteria and to what extent they may contribute to the development of bacterial resistance....... used to identify resistance genes and genetic elements associated with horizontal gene transfer. Thirteen bacterial species declared on the probiotic products could not be identified and 11 non-declared Bacillus spp. were identified. Although our culture-based isolation and identification may have...

  15. Antimicrobial resistance and virulence factors in Escherichia coli from swedish dairy calves

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    de Verdier Kerstin

    2012-01-01

    Full Text Available Abstract Background In Sweden, knowledge about the role of enteropathogenic Escherichia coli in neonatal calf diarrhea and the occurrence of antimicrobial resistance in E. coli from young calves is largely unknown. This has therapeutic concern and such knowledge is also required for prudent use of antimicrobials. Methods In a case control study Esherichia coli isolated from faecal samples from dairy calves were phenotyped by biochemical fingerprinting and analyzed for virulence genes by PCR. Antimicrobial susceptibility was tested by determination of minimum inhibitory concentration (MIC. Farm management data were collected and Fisher's exact test and univariable and multivariable logistic regression analysis were performed. Results Of 95 E. coli tested for antimicrobial susceptibility 61% were resistant to one or more substances and 28% were multi-resistant. The virulence gene F5 (K99 was not found in any isolate. In total, 21 out of 40 of the investigated virulence genes were not detected or rarely detected. The virulence genes espP, irp, and fyuA were more common in resistant E. coli than in fully susceptible isolates (P terZ was associated with calf diarrhea (P ≤ 0.01. The participating 85 herds had a median herd size of 80 lactating cows. Herds with calf diarrhea problems were larger (> 55 cows; P P There was no association between calf diarrhea and diversity of enteric E. coli. Conclusions Antimicrobial resistance was common in E. coli from pre-weaned dairy calves, occurring particularly in calves from herds experiencing calf diarrhea problems. The results indicate that more factors than use of antimicrobials influence the epidemiology of resistant E. coli. Enteropathogenic E. coli seems to be an uncommon cause of neonatal calf diarrhea in Swedish dairy herds. In practice, calf diarrhea should be regarded holistically in a context of infectious agents, calf immunity, management practices etc. We therefore advice against routine

  16. Characterization of antimicrobial resistance in Salmonella enterica strains isolated from Brazilian poultry production.

    Science.gov (United States)

    Mattiello, Samara P; Drescher, Guilherme; Barth, Valdir C; Ferreira, Carlos A S; Oliveira, Sílvia D

    2015-11-01

    Antimicrobial resistance profiles and presence of resistance determinants and integrons were evaluated in Salmonella enterica strains from Brazilian poultry. The analysis of 203 isolates showed that those from the poultry environment (88 isolates) were significantly more resistant to antimicrobials than isolates from other sources, particularly those isolated from poultry by-product meal (106 isolates). Thirty-seven isolates were resistant to at least three antimicrobial classes. Class 1 integrons were detected in 26 isolates, and the analysis of the variable region between the 5' conserved segment (CS) and 3' CS of each class 1 integron-positive isolate showed that 13 contained a typical 3' CS and 14 contained an atypical 3' CS. One Salmonella Senftenberg isolate harbored two class 1 integrons, showing both typical and atypical 3' CSs. The highest percentage of resistance was found to sulfonamides, and sul genes were detected in the majority of the resistant isolates. Aminoglycoside resistance was detected in 50 isolates, and aadA and aadB were present in 28 and 32 isolates, respectively. In addition, strA and strB were detected in 78.1 and 65.6% isolates resistant to streptomycin, respectively. Twenty-one isolates presented reduced susceptibility to β-lactams and harbored bla(TEM), bla(CMY), and/or bla(CTX-M). Forty isolates showed reduced susceptibility to tetracycline, and most presented tet genes. These results highlight the importance of the environment as a reservoir of resistant Salmonella, which may enable the persistence of resistance determinants in the poultry production chain, contributing, therefore, to the debate regarding the impacts that antimicrobial use in animal production may exert in human health.

  17. Antimicrobial Resistance Profiles of Salmonella spp. from Agricultural Environments in Fruit Production Systems.

    Science.gov (United States)

    Gomba, Annancietar; Chidamba, Lizyben; Korsten, Lise

    2016-09-01

    Foodborne disease outbreaks involving fresh produce have increased in recent years. The risk of infection from contaminated food is worsened by the increased prevalence of antibiotic-resistant strains. This study evaluated the prevalence of antibiotic resistance in Salmonella isolates (n = 263) from agricultural production systems through to the final packed product. Salmonella isolates were preliminarily identified by matrix-assisted laser desorption ionization-time-of-flight mass spectroscopy (MALDI-TOF MS) and API 20E and identities confirmed by invA gene polymerase chain reaction. Antimicrobial susceptibility was performed with 15 antimicrobial agents using the Kirby-Bauer disk diffusion test. Of the 263 Salmonella isolates assessed, 59.3% were resistant to one or more antimicrobials. The most frequently detected resistance was against chloramphenicol and kanamycin (46.7%), trimethoprim-sulfamethoxazole (28%), and streptomycin (14%), and the less frequently detected resistance was toward ampicillin (1.14%), amikacin (0.76%), and amoxicillin-clavulanic acid (0.38%). Multiple antimicrobial resistance (MAR) (resistance to ≥3 antibiotics) was found in 48.7% (76/156) isolates. The most common MAR phenotype was to chloramphenicol and trimethoprim/sulfamethoxazole-kanamycin (43.6%). Resistance to chloramphenicol, kanamycin, or trimethoprim/sulfamethoxazole was only observed in MAR phenotypes. All isolates were susceptible to ceftiofur, cefoxitin, ceftriaxone, ciprofloxacin, nalidixic acid, gentamicin, and tetracycline. This study confirms the importance of fresh produce production environments as potential reservoirs and fresh produce as carriers of antibiotic-resistant Salmonella spp. with significant clinical importance. Further studies to evaluate the actual level of health risk from these pathogens should include characterization of the antibiotic resistance determinant genes among the isolates. PMID:27294335

  18. A brief multi-disciplinary review on antimicrobial resistance in medicine and its linkage to the global environmental microbiota

    Directory of Open Access Journals (Sweden)

    Leon eCantas

    2013-05-01

    Full Text Available The discovery and introduction of antimicrobial agents to clinical medicine was one of the greatest medical triumphs of the 20th century that revolutionized the treatment of bacterial infections. However, the gradual emergence of populations of antimicrobial-resistant pathogenic bacteria resulting from use, misuse and abuse of antimicrobials has today become a major global health concern. Antimicrobial resistance genes have been suggested to originate from environmental bacteria, as clinically relevant resistance genes have been detected on the chromosome of environmental bacteria. As only a few new antimicrobials have been developed in the last decade, the further evolution of resistance poses a serious threat to public health. Urgent measures are required not only to minimize the use of antimicrobials for prophylactic and therapeutic purposes but also to look for alternative strategies for the control of bacterial infections. This review examines the global picture of antibacterial resistance, factors that favor its spread, strategies and limitations for its control and the need for continuous training of all stake-holders i.e. medical, veterinary, public health and other relevant professionals as well as human consumers of antibiotic drugs, in the appropriate use of antimicrobials.

  19. Salmonella contamination, serovars and antimicrobial resistance profiles of cattle slaughtered in South Africa

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    Evelyn Madoroba

    2016-03-01

    Full Text Available Antimicrobial resistant Salmonella are among the leading causes of foodborne infections. Our aim was to determine Salmonella contamination during cattle slaughter in South African rural abattoirs (n = 23 and environmental samples. Furthermore, antimicrobial resistance patterns of the Salmonella isolates were determined. Samples of cattle faeces (n = 400, carcass sponges (n = 100, intestinal contents (n = 62, hides (n = 67, and water from the abattoirs (n = 75 were investigated for Salmonella species using microbiological techniques and species-specific polymerase chain reaction targeting the invA gene. In total 92 Salmonella species isolates were recovered. The Salmonella mean frequency of occurrence on hides, carcasses, and intestinal contents was 35.37% (n = 81. Eleven faecal samples (2.75% tested positive for Salmonella. The predominant serovar was Salmonella Enteritidis. Diverse serovars that were identified on carcasses were not necessarily found on the hides and intestinal contents. The inconsistent occurrence of the diverse Salmonella serovars on hides, carcasses, and intestinal contents implies that in addition to carriage on hides and in intestinal contents, other external factors also play an important role regarding carcass contamination. The 92 Salmonella were serotyped and tested for susceptibility towards the following antimicrobials: ampicillin, cefotaxime, enrofloxacin, kanamycin, and oxytetracycline using the disk diffusion method. Most Salmonella (n = 66; 71.7% isolates were resistant to at least one antimicrobial with highest resistance observed towards oxytetracycline (51.90%, which highlights the need for strict hygiene during slaughter and prudent antimicrobial use during animal production. In conclusion, cattle slaughtered in South African rural abattoirs harbour diverse Salmonella serovars that are resistant to antimicrobials, which could be a public health risk. The findings should assist policymakers with improving

  20. Marine Pseudomonas putida: a potential source of antimicrobial substances against antibiotic-resistant bacteria

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    Palloma Rodrigues Marinho

    2009-08-01

    Full Text Available Bacteria isolated from marine sponges found off the coast of Rio de Janeiro, Brazil, were screened for the production of antimicrobial substances. We report a new Pseudomonas putida strain (designated P. putida Mm3 isolated from the sponge Mycale microsigmatosa that produces a powerful antimicrobial substance active against multidrug-resistant bacteria. P. putida Mm3 was identified on the basis of 16S rRNA gene sequencing and phenotypic tests. Molecular typing for Mm3 was performed by RAPD-PCR and comparison of the results to other Pseudomonas strains. Our results contribute to the search for new antimicrobial agents, an important strategy for developing alternative therapies to treat infections caused by multidrug-resistant bacteria.

  1. The antimicrobial resistance crisis: causes, consequences and management.

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    Carolyn Anne Michael

    2014-09-01

    Full Text Available The Antimicrobial Resistance (AMR crisis is the increasing global incidence of infectious diseases affecting the human population, which are untreatable with any known antimicrobial agent. This crisis will have a devastating cost on human society as both debilitating and lethal diseases increase in frequency and scope. Three major factors determine this crisis: 1/ The increasing frequency of AMR phenotypes amongst microbes is an evolutionary response to the widespread use of antimicrobials. 2/ The large and globally connected human population allows pathogens in any environment access to all of humanity. 3/ The extensive and often unnecessary use of antimicrobials by humanity provides the strong selective pressure that is driving the evolutionary response in the microbial world. Of these factors, the size of the human population is least amenable to rapid change. In contrast the remaining two factors may be affected, so offering a means of managing the crisis: The rate at which AMR, as well as virulence factors evolve in microbial world may be slowed by reducing the applied selective pressure. This may be accomplished by radically reducing the global use of current and prospective antimicrobials. Current management measures to legislate the use of antimicrobials and to educate the healthcare world in the issues, while useful, have not comprehensively addressed the problem of achieving an overall reduction in the human use of antimicrobials. We propose that in addition to current measures and increased research into new antimicrobials and diagnostics, a comprehensive education programme will be required to change the public paradigm of antimicrobial usage from that of a first line treatment to that of a last resort when all other therapeutic options have failed.

  2. Susceptibility of Pediococcus isolates to antimicrobial compounds in relation to hop-resistance and beer-spoilage

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    Ziola Barry

    2009-09-01

    Full Text Available Abstract Background Though important in the context of food microbiology and as potential pathogens in immuno-compromised humans, bacterial isolates belonging to the genus Pediococcus are best known for their association with contamination of ethanol fermentation processes (beer, wine, or fuel ethanol. Use of antimicrobial compounds (e.g., hop-compounds, Penicillin by some industries to combat Pediococcus contaminants is long-standing, yet knowledge about the resistance of pediococci to antimicrobial agents is minimal. Here we examined Pediococcus isolates to determine whether antibiotic resistance is associated with resistance to hops, presence of genes known to correlate with beer spoilage, or with ability to grow in beer. Results Lactic acid bacteria susceptibility test broth medium (LSM used in combination with commercially available GPN3F antimicrobial susceptibility plates was an effective method for assessing antimicrobial susceptibility of Pediococcus isolates. We report the finding of Vancomycin-susceptible Pediococcus isolates from four species. Interestingly, we found that hop-resistant, beer-spoilage, and beer-spoilage gene-harbouring isolates had a tendency to be more susceptible, rather than more resistant, to antimicrobial compounds. Conclusion Our findings indicate that the mechanisms involved in conferring hop-resistance or ability to spoil beer by Pediococcus isolates are not associated with resistance to antibiotics commonly used for treatment of human infections. Also, Vancomycin-resistance was found to be isolate-specific and not intrinsic to the genus as previously believed.

  3. Oral antimicrobials increase antimicrobial resistance in porcine E. coli--a systematic review.

    Science.gov (United States)

    Burow, E; Simoneit, C; Tenhagen, B-A; Käsbohrer, A

    2014-03-01

    Administration of antimicrobials to livestock increases the risk of antimicrobial resistance (AMR) in commensal bacteria. Antimicrobials in pig production are usually administered per pen via feed which implies treatment of sick alongside with healthy animals. The objective of this systematic literature review was to investigate the effect of orally administered antimicrobials on AMR in Escherichia coli of swine. Studies published in peer reviewed journals were retrieved from the international online databases ISI Web of Knowledge, PubMed, Scopus and the national electronic literature data base of Deutsches Institut für Medizinische Dokumentation und Information. The studies were assessed using the eligibility criteria English or German language, access to full paper version, defined treatment and control group (initial value or non-treatment) as well as administration and resistance testing of the same antimicrobial class. In the qualitative synthesis, only studies were included presenting the summary measures odds ratio or prevalence of resistance, the category of the applied antimicrobial and the dosage. An effect of the antimicrobial on AMR in E. coli was evaluated as an "increase", "no effect" or "decrease" if the odds or alternatively the prevalence ratio were >1.0, 1.0 or <1.0, respectively. Eleven studies, describing 36 different trials, fulfilled the eligibility criteria and were finally assessed. An increase of AMR in E. coli was found in 10 out of 11 trials comparing AMR after with AMR prior to oral treatment and in 22 of the 25 trials comparing orally treated with untreated groups. Effects expressed as odds or prevalence ratios were highest for the use of aminoglycosides, quinolones and tetracycline. There was no clear association between the reported dosage and AMR towards tetracycline. Information on antimicrobial substance and dosage was missing in 4 and 5 of the 11 finally selected studies. The 36 identified trials were inhomogenous in usage and

  4. Virulence Factors of Staphylococcus aureus Isolated from Korean Pork bulgogi: Enterotoxin Production and Antimicrobial Resistance

    OpenAIRE

    Jung, Byeong Su; Lee, Yong Ju; Lee, Na-Kyoung; Kim, Hyoun Wook; Oh, Mi-Hwa; Paik, Hyun-Dong

    2015-01-01

    The aim of this study was to investigate the antimicrobial resistance profiles of and the enterotoxin gene distribution in 4 strains of Staphylococcus aureus (S10-2, S10-3, S12-2, and S13-2) isolated from 90 bulgogi samples. The S. aureus enterotoxin H gene (seh) was found in all the strains, while the S. aureus enterotoxin A gene (sea) was found only in 3 of the 4 strains. The S10-2 strain expressed a combination of enterotoxin genes - seg, seh, sei, sej, selm, and seln. The strains S10-2 an...

  5. Staphylococcus aureus resistance to topical antimicrobials in atopic dermatitis*

    Science.gov (United States)

    Bessa, Giancarlo Rezende; Quinto, Vanessa Petry; Machado, Daiane Corrêa; Lipnharski, Caroline; Weber, Magda Blessmann; Bonamigo, Renan Rangel; D'Azevedo, Pedro Alves

    2016-01-01

    Background Topical antimicrobial drugs are indicated for limited superficial pyodermitis treatment, although they are largely used as self-prescribed medication for a variety of inflammatory dermatoses, including atopic dermatitis. Monitoring bacterial susceptibility to these drugs is difficult, given the paucity of laboratory standardization. Objective To evaluate the prevalence of Staphylococcus aureus topical antimicrobial drug resistance in atopic dermatitis patients. Methods We conducted a cross-sectional study of children and adults diagnosed with atopic dermatitis and S. aureus colonization. We used miscellaneous literature reported breakpoints to define S. aureus resistance to mupirocin, fusidic acid, gentamicin, neomycin and bacitracin. Results A total of 91 patients were included and 100 S. aureus isolates were analyzed. All strains were methicillin-susceptible S. aureus. We found a low prevalence of mupirocin and fusidic acid resistance (1.1% and 5.9%, respectively), but high levels of neomycin and bacitracin resistance (42.6% and 100%, respectively). Fusidic acid resistance was associated with more severe atopic dermatitis, demonstrated by higher EASI scores (median 17.8 vs 5.7, p=.009). Our results also corroborate the literature on the absence of cross-resistance between the aminoglycosides neomycin and gentamicin. Conclusions Our data, in a southern Brazilian sample of AD patients, revealed a low prevalence of mupirocin and fusidic acid resistance of S. aureus atopic eczema colonizer strains. However, for neomycin and bacitracin, which are commonly used topical antimicrobial drugs in Brazil, high levels of resistance were identified. Further restrictions on the use of these antimicrobials seem necessary to keep resistance as low as possible.

  6. Salmonella contamination, serovars and antimicrobial resistance profiles of cattle slaughtered in South Africa.

    Science.gov (United States)

    Madoroba, Evelyn; Kapeta, Daniel; Gelaw, Awoke K

    2016-01-01

    Antimicrobial resistant Salmonella are among the leading causes of foodborne infections. Our aim was to determine Salmonella contamination during cattle slaughter in South African rural abattoirs (n = 23) and environmental samples. Furthermore, antimicrobial resistance patterns of the Salmonella isolates were determined. Samples of cattle faeces (n = 400), carcass sponges (n = 100), intestinal contents (n = 62), hides (n = 67), and water from the abattoirs (n = 75) were investigated for Salmonella species using microbiological techniques and species-specific polymerase chain reaction targeting the invA gene. In total 92 Salmonella species isolates were recovered. The Salmonella mean frequency of occurrence on hides, carcasses, and intestinal contents was 35.37% (n = 81). Eleven faecal samples (2.75%) tested positive for Salmonella. The predominant serovar was Salmonella Enteritidis. Diverse serovars that were identified on carcasses were not necessarily found on the hides and intestinal contents. The inconsistent occurrence of the diverse Salmonella serovars on hides, carcasses, and intestinal contents implies that in addition to carriage on hides and in intestinal contents, other external factors also play an important role regarding carcass contamination. The 92 Salmonella were serotyped and tested for susceptibility towards the following antimicrobials: ampicillin, cefotaxime, enrofloxacin, kanamycin, and oxytetracycline using the disk diffusion method. Most Salmonella (n = 66; 71.7%) isolates were resistant to at least one antimicrobial with highest resistance observed towards oxytetracycline (51.90%), which highlights the need for strict hygiene during slaughter and prudent antimicrobial use during animal production. In conclusion, cattle slaughtered in South African rural abattoirs harbour diverse Salmonella serovars that are resistant to antimicrobials, which could be a public health risk. The findings should assist policymakers with improving implementation

  7. Antimicrobial Resistance in Generic Escherichia coli Isolates from Wild Small Mammals Living in Swine Farm, Residential, Landfill, and Natural Environments in Southern Ontario, Canada▿

    OpenAIRE

    Allen, Samantha E.; Boerlin, Patrick; Janecko, Nicol; Lumsden, John S; Barker, Ian K; Pearl, David L; Reid-Smith, Richard J.; Jardine, Claire

    2010-01-01

    To assess the impacts of different types of human activity on the development of resistant bacteria in the feces of wild small mammals, we compared the prevalences and patterns of antimicrobial resistance and resistance genes in generic Escherichia coli and Salmonella enterica isolates from fecal samples collected from wild small mammals living in four environments: swine farms, residential areas, landfills, and natural habitats. Resistance to antimicrobials was observed in E. coli isolates f...

  8. Antibiotic and Antimicrobial Resistance: Threat Report 2013

    Science.gov (United States)

    ... this? Submit What's this? Submit Button Antibiotic Resistance Threats in the United States, 2013 Recommend on Facebook Tweet Share Compartir This report, Antibiotic resistance threats in the United States, 2013 gives a first- ...

  9. How Fitness Reduced, Antimicrobial Resistant Bacteria Survive and Spread

    DEFF Research Database (Denmark)

    Græsbøll, Kaare; Nielsen, Søren Saxmose; Toft, Nils;

    2014-01-01

    More than 30% of E. coli strains sampled from pig farms in Denmark over the last five years were resistant to the commonly used antimicrobial tetracycline. This raises a number of questions: How is this high level sustained if resistant bacteria have reduced growth rates? Given that there are mul......More than 30% of E. coli strains sampled from pig farms in Denmark over the last five years were resistant to the commonly used antimicrobial tetracycline. This raises a number of questions: How is this high level sustained if resistant bacteria have reduced growth rates? Given...... for the individual strains in each pig were implemented. We demonstrate how competitive growth between multiple bacterial strains in individual pigs, and the transmission between pigs in a pen allow for strains of antimicrobial resistant bacteria to persist in a pig population to different extents, and how quickly...... homogenous and how resistant the bacterial population becomes. Most important: resistant bacteria are demonstrated to survive with a disadvantage in growth rate of well over 10%....

  10. Antimicrobial resistance in commensal Escherichia coli in veal calves is associated with antimicrobial drug use

    NARCIS (Netherlands)

    Bosman, A.B.; Wagenaar, J.A.; Stegeman, J.A.; Vernooij, J.C.M.; Mevius, D.J.

    2014-01-01

    The aim of this study was to determine the association between farm management factors, including antimicrobial drug usage, and resistance in commensal Escherichia coli isolates from the faeces of white veal calves. Ninety E. coli isolates from one pooled sample per farm (n = 48) were tested for the

  11. Antimicrobial susceptibility and clarithromycin resistance patterns of Helicobacter pylori clinical isolates in Vietnam.

    Science.gov (United States)

    Quek, Camelia; Pham, Son T; Tran, Kieu T; Pham, Binh T; Huynh, Loc V; Luu, Ngan B L; Le, Thao K T; Quek, Kelly; Pham, Van H

    2016-01-01

    Helicobacter pylori is a gastric pathogen that causes several gastroduodenal disorders such as peptic ulcer disease and gastric cancer.  Eradication efforts of H. pylori are often hampered by antimicrobial resistance in many countries, including Vietnam.  Here, the study aimed to investigate the occurrence of antimicrobial resistance among H. pylori clinical isolates across 13 hospitals in Vietnam.  The study further evaluated the clarithromycin resistance patterns of H. pylori strains.  In order to address the study interests, antimicrobial susceptibility testing, epsilometer test and PCR-based sequencing were performed on a total of 193 strains isolated from patients, including 136 children (3-15 years of age) and 57 adults (19-69 years of age).  Antimicrobial susceptibility testing showed that the overall resistance to amoxicillin, clarithromycin, levofloxacin, metronidazole, and tetracycline was 10.4%, 85.5%, 24.4%, 37.8%, and 23.8% respectively.  The distribution of minimum inhibitory concentrations (MICs) of clarithromycin-resistant strains was 85.5% with MIC >0.5 μg/mL.  The majority of the clarithromycin resistant isolates (135 of 165 subjects) have MICs ranging from 2 μg/mL to 16 μg/mL.  Furthermore, sequencing detection of mutations in 23S rRNA gene revealed that strains resistant and susceptible to clarithromycin contained both A2143G and T2182C mutations.  Of all isolates, eight clarithromycin-resistant isolates (MIC >0.5 μg/mL) had no mutations in the 23S rRNA gene.  Collectively, these results demonstrated that a proportion of clarithromycin-resistant H. pylori strains, which are not related to the 23S rRNA gene mutations, could be potentially related to other mechanisms such as the presence of an efflux pump or polymorphisms in the CYP2C19 gene.  Therefore, the present study suggests that providing susceptibility testing prior to treatment or alternative screening strategies for antimicrobial resistance is important for future clinical

  12. Antimicrobial resistance of fecal aerobic gram-negative bacilli in different age groups in a community.

    OpenAIRE

    Leistevuo, T; Leistevuo, J; Osterblad, M; Arvola, T. (Timo); Toivonen, P; Klaukka, T; Lehtonen, A; Huovinen, P.

    1996-01-01

    We measured the occurrence of antimicrobial resistance in fecal aerobic gram-negative bacilli by age in community subjects. For none of the eight antimicrobial agents studied were there any statistically significant differences in the carriage rates of resistance in different age groups. Bacterial resistance was common in all age groups, including the children, and occurred for all antimicrobial agents tested.

  13. Ancient antimicrobial peptides kill antibiotic-resistant pathogens: Australian mammals provide new options.

    Directory of Open Access Journals (Sweden)

    Jianghui Wang

    Full Text Available BACKGROUND: To overcome the increasing resistance of pathogens to existing antibiotics the 10×'20 Initiative declared the urgent need for a global commitment to develop 10 new antimicrobial drugs by the year 2020. Naturally occurring animal antibiotics are an obvious place to start. The recently sequenced genomes of mammals that are divergent from human and mouse, including the tammar wallaby and the platypus, provide an opportunity to discover novel antimicrobials. Marsupials and monotremes are ideal potential sources of new antimicrobials because they give birth to underdeveloped immunologically naïve young that develop outside the sterile confines of a uterus in harsh pathogen-laden environments. While their adaptive immune system develops innate immune factors produced either by the mother or by the young must play a key role in protecting the immune-compromised young. In this study we focus on the cathelicidins, a key family of antimicrobial peptide genes. PRINCIPAL FINDING: We identified 14 cathelicidin genes in the tammar wallaby genome and 8 in the platypus genome. The tammar genes were expressed in the mammary gland during early lactation before the adaptive immune system of the young develops, as well as in the skin of the pouch young. Both platypus and tammar peptides were effective in killing a broad range of bacterial pathogens. One potent peptide, expressed in the early stages of tammar lactation, effectively killed multidrug-resistant clinical isolates of Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii. CONCLUSIONS AND SIGNIFICANCE: Marsupial and monotreme young are protected by antimicrobial peptides that are potent, broad spectrum and salt resistant. The genomes of our distant relatives may hold the key for the development of novel drugs to combat multidrug-resistant pathogens.

  14. Antimicrobial resistance patterns in Danish isolates of Flavobacterium psychrophilum

    DEFF Research Database (Denmark)

    Bruun, Morten Sichlau; Schmidt, A.S.; Madsen, Lone;

    2000-01-01

    were tested and the resulting antibiograms were used to predict the theoretical therapeutic efficacy and to evaluate if resistance had changed as a course of time. Antimicrobial agents included in this investigation were oxolinic acid (OXA), amoxicillin (AMX), potentiated sulfadiazine, oxytetracycline......The resistance pattern of Flavobacterium psychrophilum to the antimicrobial agents used in fish farming in Denmark was assessed in vitro using an agar dilution method. After identification of 387 isolates from clinical outbreaks of rainbow trout fry syndrome (RTFS) and the environment, the isolates...... (OTC) and florfenicol (FLO). We found that F. psychrophilum isolates divided in susceptible and resistant clusters reflecting the reduced efficacy in practice when using OTC and AMX. The most recent isolates were less susceptible to AMX and OXA, whereas resistance to OTC seemed stable over the last 5...

  15. Aedesin: structure and antimicrobial activity against multidrug resistant bacterial strains.

    Directory of Open Access Journals (Sweden)

    Sylvain Godreuil

    Full Text Available Multidrug resistance, which is acquired by both Gram-positive and Gram-negative bacteria, causes infections that are associated with significant morbidity and mortality in many clinical settings around the world. Because of the rapidly increasing incidence of pathogens that have become resistant to all or nearly all available antibiotics, there is a need for a new generation of antimicrobials with a broad therapeutic range for specific applications against infections. Aedesin is a cecropin-like anti-microbial peptide that was recently isolated from dengue virus-infected salivary glands of the Aedes aegypti mosquito. In the present study, we have refined the analysis of its structural characteristics and have determined its antimicrobial effects against a large panel of multidrug resistant bacterial strains, directly isolated from infected patients. Based the results from nuclear magnetic resonance spectroscopy analysis, Aedesin has a helix-bend-helix structure typical for a member of the family of α-helix anti-microbial peptides. Aedesin efficiently killed Gram-negative bacterial strains that display the most worrisome resistance mechanisms encountered in the clinic, including resistance to carbapenems, aminoglycosides, cephalosporins, 4th generation fluoroquinolones, folate inhibitors and monobactams. In contrast, Gram-positive strains were insensitive to the lytic effects of the peptide. The anti-bacterial activity of Aedesin was found to be salt-resistant, indicating that it is active under physiological conditions encountered in body fluids characterized by ionic salt concentrations. In conclusion, because of its strong lytic activity against multidrug resistant Gram-negative bacterial strains displaying all types of clinically relevant resistance mechanisms known today, Aedesin might be an interesting candidate for the development of alternative treatment for infections caused by these types of bacteria.

  16. Emerging antimicrobial resistance pattern of Helicobacter pylori in central Gujarat

    OpenAIRE

    H B Pandya; Harihar Har Agravat; J S Patel; NRK Sodagar

    2014-01-01

    Background: Antimicrobial resistance is a growing problem in H. pylori treatment. The study was intended to evaluate the prevalence of resistance amongst 80 H.pylori isolates cultured from biopsy taken during routine endoscopies in 2008-2011. Materials and Methods: 855 gastro duodenal biopsies were collected and cultured on H.pylori selective medium (containing Brucella agar and Columbia agar (Hi media), with Skirrow′s supplement (antibiotic supplement) and 7% human blood cells). H.pylori was...

  17. Horizontal gene transfer—emerging multidrug resistance in hospital bacteria

    Institute of Scientific and Technical Information of China (English)

    SenkaDZIDIC; VladimirBEDEKOVIC

    2003-01-01

    The frequency and spectrum of antibiotic resistant infections have increased worldwide during the past few decades. This increase has been attributed to a combination of microbial characteristics, the selective pressure of antimicrobial use, and social and technical changes that enhance the transmission of resistant organisms. The resistance is acquired by mutational changer or by the acquisition of resistance-encoding genetic material which is transfered from another bacteria. The spread of antibiotic resistance genes may be causally related to the overuse of antibiotics in human health care and in animal feeds, increased use of invasive devices and procedures, a greater number of susceptible hosts, and lapses in infection control practices leading to increased transmission of resistant organisms. The resistance gene sequences are integrated by recombination into several classes of naturally occurring gene expression cassettes and disseminated within the microbial population by horizontal gene transfer mechanisms: transformation, conjugation or transduction. In the hospital, widespread use of antimicrobials in the intensive care units (ICU) and for immunocompromised patients has resulted in the selection of multidrug-resistant organisms. Methicilin-resistant Staphylococci, vancomycin resistant Enterococci and extended-spectrum betalactamase(ESBL) producing Gram negative bacilli are identified as major phoblem in nosocomial infections. Recent surveillance studies have demonstrated trend towares more seriously ill patients suffering from multidrug-resistant nosocomial infections. Emergence of multiresistant bacteria and spread of resistance genes should enforce the aplication of strict prevention strategies, including changes in antibiotic treatment regimens, hygiene measures, infection prevention and control of horizontal nosocomial transmission of organisms.

  18. New antimicrobial drug resistance and epidemiological typing patterns of Staphylococci from clinical isolates and raw meats.

    Science.gov (United States)

    Lee, Do Kyung; Hwang, Jae Ung; Baek, Eun Hye; Lee, Kang Oh; Kim, Kyung Jae; Ha, Nam Joo

    2008-08-01

    The antimicrobial susceptibilities of Staphylococcus isolated from clinical isolates and raw meats were tested for six different antimicrobial agents that are in widespread clinical use in Korea and four new antimicrobials, linezolid, quinupristin/dalfopristin, daptomycin, and tigecycline. And this study analyzed the mecA genes and genetic patterns of MRSA by performing epidemiological studies using the PCR method. 46%, 51%, and 79% of clinical isolates were identified as MRSA in 1998, 1999, and 2005, respectively, and the mecA gene was detected in 82% of these isolates. Of the 133 staphylococci isolated from raw meats, 18% of the isolates were found to be resistant to methicillin, but none of these isolates showed the presence of the mecA gene. New antimicrobials, which have rarely or not yet been used in Korean hospitals, showed high activity against all staphylococcal isolates including methicillin-resistant isolates. The randomly amplified polymorphic DNA (RAPD) patterns of MRSA isolates differed significantly between clinical isolates and raw meat isolates. PMID:18787791

  19. Antimicrobial resistance of non-typhoidal Salmonella isolates from egg layer flocks and egg shells.

    Science.gov (United States)

    Pande, Vivek V; Gole, Vaibhav C; McWhorter, Andrea R; Abraham, Sam; Chousalkar, Kapil K

    2015-06-16

    This study was conducted to examine the antimicrobial resistance (AMR) of Salmonella spp. isolated from commercial caged layer flocks in New South Wales and South Australia. All Salmonella isolates (n=145) were subjected to phenotypic and genotypic characterisation of AMR and carriage of integrons. The majority of Salmonella isolates (91.72%) were susceptible to all antimicrobials tested in this study. Limited resistance was observed to amoxicillin and ampicillin (5.51%), tetracycline (4.13%), cephalothin (2.06%) and trimethoprim (0.68%). None of the isolates were resistant to cefotaxime, ceftiofur, ciprofloxacin, chloramphenicol, gentamycin, neomycin or streptomycin. A low frequency of Salmonella isolates (4.83%) harboured antimicrobial resistance genes and a class 1 integron. The most commonly detected AMR genes among the Salmonella isolates were blaTEM (2.07%), tet A (1.38%) and dhfrV (0.69%). Overall, Salmonella enterica isolates exhibited a low frequency of AMR and represent a minimal public health risk associated with the emergence of multidrug resistant Salmonella spp. from the Australian layer industry.

  20. Monitoring of antimicrobial resistance in pathogenic bacteria from livestock animals.

    Science.gov (United States)

    Wallmann, Jürgen

    2006-06-01

    Facing the problem of development and spreading of bacterial resistance, preventive strategies are considered the most appropriate means to counteract. The establishment of corresponding management options relies on scientifically defensible efforts to obtain objective data on the prevalence of bacterial resistance in healthy and diseased livestock. Additionally, detailed statistics are needed on the overall amount of antimicrobial agents dispensed in Germany. The collection of valid data on the prevalence of resistance requires representative and cross-sectional studies. The German national antimicrobial resistance monitoring of the Federal Office of Consumer Protection and Food Safety (BVL) determines the current quantitative resistance level of life-stock pathogens, in order to permit the evaluation and surveillance of the distribution of resistances on a valid basis. Essential key features determining the design of these studies comprise (1) a statistically valid sampling program. This incorporates regional differences in animal population density, (2) the avoidance of "copy strains", (3) testing of no more than two bacterial strains belonging to one species per herd, (4) testing only if no antimicrobial therapy preceded sample collection, and (5) the use of standardized methods [e.g. microdilution broth method to determine the minimal inhibitory concentration (MIC)]. The analysis and interpretation of this data permits reliable identification and definition of epidemiological characteristics of resistance and its development in animal associated bacteria, such as geographically and time wise differentiated profiles on its prevalence, the emergence of unknown phenotypes of resistance and an assessment of the threat resistant bacteria from animals pose for humans. In applied antimicrobial therapy, the data can serve as a decision guidance in choosing the antimicrobial agent most adapted to the prevailing epidemiological situation. The susceptibility testing

  1. ANTIMICROBIAL RESISTANCE PATTERN OF STAPHYLOCOCCUS AUREUS ISOLATES FROM DAKSHINA KANNADA

    Directory of Open Access Journals (Sweden)

    Rao Venkatakrishna

    2011-03-01

    Full Text Available Methicillin resistant Staphylococcus aureus (MRSA is an important cause of infections in hospitals and pose a great challenge to the treating clinicians; even emergence of vancomycin resistance has been reported. Therefore the knowledge of prevalence of MRSA and their antimicrobial profile becomes necessary. This study is aimed to determine prevalence of MRSA and their antimicrobial sensitivity pattern in Dakshina Kannada.Clinical specimens and carrier samples were cultured as per standard methods. The isolates were identified by using catalase test, coagulase tube test, mannitol fermentation and DNAase test. Antimicrobial susceptibility test was done for the isolates as per Kirby-Bauer disc diffusion method; the isolates were also tested for methicillin resistance using oxacillin and cefoxitin discs.A total of 250 isolates were tested (200 clinical isolates and 50 from carriers and 67 MRSA isolates were obtained (52 clinical samples and 15 from carriers. The degree of resistance to penicillin, ampicillin, ciprofloxacin, clindamycin and erythromycin were 100%, 100%, 53-56%, 14-16 % and 45-48% respectively. Resistance to vancomycin was not found. As the degree of resistance of MRSA towards antibiotics varies from region to region, in vitro susceptibility testing of every isolate of MRSA in clinical laboratories is inevitable.

  2. A literature review of antimicrobial resistance in Pathogens associated with bovine respiratory disease.

    Science.gov (United States)

    DeDonder, K D; Apley, M D

    2015-12-01

    The objective of this paper was to perform a critical review of the literature as it pertains to the current status of antimicrobial resistance in pathogens associated with bovine respiratory disease (BRD) in beef cattle and to provide a concise yet informative narrative on the most relevant publications available. As such, the scientific literature contained in PubMed, AGRICOLA, and CAB were searched in February of 2014 for articles related to susceptibility testing of Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni from cases of BRD. Titles and abstracts were read and 105 articles that were relevant to the subject of BRD antibiotic resistance were attained for further review. After the application of exclusion criterion (publications must have originated from North America, be in English, adhere to standards set forth by the Clinical and Laboratory Standards Institute, and be concerning antimicrobial resistance in BRD in beef cattle), 16 articles remained and are the focus of this publication. Due to the disparate data from the few studies that investigate susceptibility testing of BRD pathogens, a quantitative assessment or meta-analysis was not performed on the studies presented in this review. However, considering diagnostic lab data, there appears to be a clear trend of a decrease in susceptibility of the three major BRD pathogens to the antimicrobials used commonly for treatment and control of BRD. Studies performing sensitivity testing on healthy cattle report much lower resistance, but it remains unclear if this is because of a true lack of resistance mechanisms, or if the isolates do contain quiescent genes for resistance that are only phenotypically expressed following the administration of an antimicrobial for either treatment or control of BRD. Future research to address this question of genotype and phenotypic expression before and after antimicrobial administration will further advance our knowledge in this area.

  3. Antimicrobial resistance of Staphylococcus spp. from small ruminant mastitis in Brazil

    Directory of Open Access Journals (Sweden)

    Chirles A. França

    2012-08-01

    Full Text Available The study aimed to determine the antimicrobial resistance patterns and to identify molecular resistance markers in Staphylococcus spp. (n=210 isolated from small ruminant mastitis in Brazil. The antimicrobial resistance patterns were evaluated by the disk diffusion test and by detection of the presence of mecA, blaZ, ermA, ermB, ermC and msrA genes by PCR. The efflux pump test was performed using ethidium bromide and biofilm production was determined by Congo red agar test along with PCR for detection of the icaD gene. The isolates were most resistant to amoxicillin (50.0%, streptomycin (42.8%, tetracycline (40.4%, lincomycin (39.0% and erythromycin (33.8%. Pan-susceptibility to all tested drugs was observed in 71 (33.8% isolates and 41 Staphylococcus isolates were positive for the efflux pump. Although phenotypic resistance to oxacillin was observed in 12.8% of the isolates, none harbored the mecA gene. However, 45.7% of the isolates harbored blaZ indicating that beta-lactamase production was the main mechanism associated with staphylococci resistance to beta-lactams in the present study. The other determinants of resistance to antimicrobial agents ermA, ermB, ermC, and msrA were observed in 1.4%, 10.4%, 16.2%, and 0.9% of the isolates, respectively. In addition, the icaD gen was detected in 32.9% of the isolates. Seventy three isolates (54 from goats and 19 from sheep were negative for all resistance genes tested and 69 isolates presented two or more resistance genes. Association among blaZ, ermA, ermB, ermC and efflux pump were observed in 17 isolates, 14 of which originated from goats and three from sheep. The data obtained in this study show the resistance of the isolates to beta-lactamics, which may be associated with the use of antimicrobial drugs without veterinary control.

  4. Antimicrobial resistance of Aeromonas hydrophila isolated from different food sources: A mini-review.

    Science.gov (United States)

    Stratev, Deyan; Odeyemi, Olumide A

    2016-01-01

    Aeromonas hydrophila is a Gram-negative, oxidase-positive, facultative, anaerobic, opportunistic aquatic pathogen. A. hydrophila produces virulence factors, such as hemolysins, aerolysins, adhesins, enterotoxins, phospholipase and lipase. In addition to isolation from aquatic sources, A. hydrophila has been isolated from meat and meat products, milk and dairy products, and vegetables. However, various studies showed that this opportunistic pathogen is resistant to commercial antibiotics. This is attributed to factors such as the indiscriminate use of antibiotics in aquaculture, plasmids or horizontal gene transfer. In this report, we highlight the occurrence, prevalence and antimicrobial resistance of A. hydrophila isolated from different food samples. The presence of antimicrobial-resistant A. hydrophila in food poses threats to public and aquatic animal health. PMID:26588876

  5. Characterization of antimicrobial resistance in Klebsiella species isolated from chicken broilers.

    Science.gov (United States)

    Wu, Hao; Wang, Mingyu; Liu, Yuqing; Wang, Xinhua; Wang, Yunkun; Lu, Jinxing; Xu, Hai

    2016-09-01

    The prevalence of antimicrobial resistant Klebsiella pneumoniae in poultry products has been a public concern, as it severely endangers food safety and human health. In this study, we investigated 90 antimicrobial resistant Klebsiella strains that were isolated from a commercial broiler slaughter plant in Shandong province of China. Nearly all (89/90) of the isolates were identified as infectious phylogenetic group KpI-type K. pneumoniae. Out of these 90 strains, 87 (96.7%) were multidrug-resistant isolates, and 87 (96.7%) were extended-spectrum beta-lactamase (ESBL)-producing isolates. An analysis of the prevalence of quinolone resistance genes showed that 7.8%, 77.8%, 26.7%, and 2.2% of the strains carried the qnrA, qnrB, qnrS, and qepA genes, respectively. An analysis of beta-lactam resistance genes showed that a high percentage of the strains contain the blaTEM (76.7%), blaSHV (88.9%), and blaCTX-M (75.6%) genes, among which three blaSHV subtypes (blaSHV-1, n=30; blaSHV-11, n=38; blaSHV-12, n=12) and three blaCTX-M subtypes (blaCTX-M-14, n=14; blaCTX-M-15, n=35; blaCTX-M-55, n=19) were found. A further investigation of mobile genetic elements involved in horizontal multidrug resistance gene transfer showed the presence of class 1 and 2 integrons in 77 (85.6%) and five (5.6%) isolates, respectively, while no class 3 integrons were detected. Four types of class 1 integrons containing specific gene cassette arrays (dfrA12-orfF-aadA2, dfrA17-aadA5, dfrA1-aadA1, and empty) were identified. Only one gene cassette array (dfrA1-sat2-aadA1) was detected in the class 2 integrons. Furthermore, four different types of insertion sequence common region 1 (ISCR1)-mediated downstream structures were successfully identified in 46 class 1 integron-positive isolates, among which ISCR1-sapA-like-qnrB2-qacEΔ1 was the most commonly observed structure. Chi-square tests revealed a significant association between ESBL genes, plasmid-mediated quinolone resistance (PMQR) genes, and

  6. Antimicrobial resistance of Salmonella serovars isolated from beef at retail markets in the north Vietnam.

    Science.gov (United States)

    Thai, Truong Ha; Hirai, Takuya; Lan, Nguyen Thi; Shimada, Akinori; Ngoc, Pham Thi; Yamaguchi, Ryoji

    2012-09-01

    Approximately 39.9% (63/158) of beef samples collected from retail markets in Hanoi from January to June 2009 were Salmonella-positive. Nine Salmonella serovars, Anatum (28.6%), Rissen (25.4%), Weltevreden (12.7%), Typhimurium (7.9%), Derby (7.9%), Lexington (7.9%), Dublin (4.6%), Newport (3.2%) and London (1.8%), were identified. Thirty-seven (58.7%) of the 63 Salmonella isolates were resistant to at least one antimicrobial tested, of which 29 (46%) isolates showed multidrug resistance (MDR). The isolates were commonly resistant to tetracycline (46.0%), sulphonamide (39.7%), ampicilline (31.7%), streptomycin (30.2%), trimethoprim (28.6%), kanamycin (28.6%) and chloramphenicol (22.2%). Fourteen (bla(TEMV), bla(OXA-1), aadA1, aadA2, sul1, tetA, tetB, tetG, cmlA1, floR, dfrA1, dfrA12, aac (3)-IV and aphA1-1AB) out of 22 antimicrobial resistance genes were detected by PCR from the resistant isolates. The catA1, Kn, blaPSE-1 genes and plasmid-mediated quinolones resistance (PMQR) genes such as qnrA, qnrB, qnrS, qepA and acc (6')-ib-cr were not detected. Mutations in the gyrA gene leading to the amino acid changes Ser83Phe and/or Asp87Asn were found in 6 out of the 11 quinolone-resistant isolates. The data revealed that multidrug resistant Salmonella strains were widely distributed in north Vietnam via the food chain and might contain multiple genes specifying identical resistant phenotypes. Thus, continuous studies are necessary to clarify the mechanisms of MDR in Salmonella and its spread in the livestock market.

  7. Analysis of Drug Resistance and Resistant Genes of Salmonella toβ-lactams Antimicrobial Agents Isolated from Pigs in Guizhou Province%贵州省猪源沙门氏菌对β-内酰胺类药耐药性及耐药基因分析

    Institute of Scientific and Technical Information of China (English)

    曹正花; 谭艾娟; 吕世明; 王雄; 杜国琴

    2016-01-01

    In order to analyse the resistance toβ-lactams antimicrobial agents and the prevalence of resistant genes of Salmonella in Guizhou province,130 Salmonella strains were isolated and iden-tified from 9 different regions of scale pig farms.The drug sensitivity to 8 kinds ofβ-lactams anti-microbial agents were determined by using the broth microdilution method.Allβ-lactams resistant isolates were detected for the presences of TEM,OXA,CTX-M and SHV genes by PCR.The re-sults showed that drug resistance of Salmonella to the commonly usedβ-lactams antimicrobial agents was very serious,and the resistance rate to ceftazidime was the highest (100%),followed by ampicillin and amoxicillin,were 76.15% and 80.77%,respectively.The resistance rates of ceft-iofur and cephalexin were the lowest (46.15%).Salmonella strains were all of multiple drug re-sistance,of which double resistance was at lowest (2.31%),and eightfold resistance was highest (4.62%),multidrug resistance mainly concentrated in fourfold to sevenfold,accounted for 88.46%.PCR results showed that TEM,OXA,CTX-M genes detection rate were 85%,75% and 46%,respectively,while the SHV gene was not inspected.Resistant phenotype was basically con-sistent with resistant genes.The results indicated that the resistance of Salmonella stains from pig toβ-lactams antimicrobial agents were widespread,and ceftazidime was particularly serious. The TEM,OXA and CTX-M genes were mainly carriedβ-lactams resistant genes in Salmonella isolates from Guizhou province.It had a great relationship between the prevalence of resistance genes and growth of antimicrobial resistance.%为了解贵州省猪源沙门氏菌对β-内酰胺类抗菌药物耐药性及其耐药基因的流行情况,本试验从贵州省9个地区规模养猪场中分离鉴定130株沙门氏菌,采用微量肉汤稀释法测定其对常用的8种β-内酰胺类抗菌药物的敏感性,并用PCR法对β-内酰胺酶耐药基因进行检测。结果显示,沙门氏菌对常

  8. Growing Burkholderia pseudomallei in biofilm stimulating conditions significantly induces antimicrobial resistance.

    Directory of Open Access Journals (Sweden)

    Chakrit Sawasdidoln

    Full Text Available BACKGROUND: Burkholderia pseudomallei, a gram-negative bacterium that causes melioidosis, was reported to produce biofilm. As the disease causes high relapse rate when compared to other bacterial infections, it therefore might be due to the reactivation of the biofilm forming bacteria which also provided resistance to antimicrobial agents. However, the mechanism on how biofilm can provide tolerance to antimicrobials is still unclear. METHODOLOGY/PRINCIPAL FINDINGS: The change in resistance of B. pseudomallei to doxycycline, ceftazidime, imipenem, and trimethoprim/sulfamethoxazole during biofilm formation were measured as minimum biofilm elimination concentration (MBEC in 50 soil and clinical isolates and also in capsule, flagellin, LPS and biofilm mutants. Almost all planktonic isolates were susceptible to all agents studied. In contrast, when they were grown in the condition that induced biofilm formation, they were markedly resistant to all antimicrobial agents even though the amount of biofilm production was not the same. The capsule and O-side chains of LPS mutants had no effect on biofilm formation whereas the flagellin-defective mutant markedly reduced in biofilm production. No alteration of LPS profiles was observed when susceptible form was changed to resistance. The higher amount of N-acyl homoserine lactones (AHLs was detected in the high biofilm-producing isolates. Interestingly, the biofilm mutant which produced a very low amount of biofilm and was sensitive to antimicrobial agents significantly resisted those agents when grown in biofilm inducing condition. CONCLUSIONS/SIGNIFICANCE: The possible drug resistance mechanism of biofilm mutants and other isolates is not by having biofilm but rather from some factors that up-regulated when biofilm formation genes were stimulated. The understanding of genes related to this situation may lead us to prevent B. pseudomallei biofilms leading to the relapse of melioidosis.

  9. Antimicrobial resistance and clonality in Acinetobacter baumannii

    OpenAIRE

    Nemec, Alexandr

    2009-01-01

    The aim of this thesis was to obtain insight into the epidemiology and molecular basis of multidrug resistance of Acinetobacter baumannii at the population level. To this aim a number of studies were performed on strains mainly from the Czech Republic (CR) which have shown in particular that (i) the vast majority of multidrug resistant (MDR) clinical isolates of A. baumannii from CR belong to clonal lineages termed EU clone I and II; (ii) these two clones have predominated among MDR hospital ...

  10. Antimicrobial resistance and presence of the SXT mobile element in Vibrio spp. isolated from aquaculture facilities.

    Science.gov (United States)

    García-Aljaro, Cristina; Riera-Heredia, Jordi; Blanch, Anicet R

    2014-07-01

    The aim of this work was to assess the susceptibility of Vibrio spp. strains isolated from fish cultures against some usually applied antibiotics and the occurrence of the SXT mobile genetic element among them. Antimicrobial resistance was assessed by the standard disk diffusion technique while the presence of the SXT mobile genetic element was determined by conventional PCR. High levels of resistance to ampicillin (70%), cefoxitin (44%), streptomycin (31%), aztreonam (25%) and sulfamethoxazole (21%) were detected, and a high inter-and-intraspecies diversity in the resistance profile was observed for the majority of the analysed isolates. The SXT mobile genetic element was detected in only 4 isolates belonging to the species V. diazotrophicus (1), V. mediterranei (2) and V. vulnificus (1), which showed a variable antibiotic resistance profile. Horizontal antibiotic resistance gene transfer from the V. diazotrophicus SXT-positive strain to a laboratory E. coli strain was demonstrated under laboratory conditions. Our results suggest that the Vibrio spp. isolated from aquaculture facilities analysed in this study, although not being pathogenic, they constitute a source of antimicrobial resistance genes that could be mobilized to other bacterial populations through mobile genetic elements. However, the low occurrence of the SXT element in these isolates supports the hypothesis that this element is not involved in the development of resistance in the majority of Vibrio spp. in the examined aquaculture facilities.

  11. Phylogenetic analysis reveals common antimicrobial resistant Campylobacter coli population in antimicrobial-free (ABF and commercial swine systems.

    Directory of Open Access Journals (Sweden)

    Macarena P Quintana-Hayashi

    Full Text Available The objective of this study was to compare the population biology of antimicrobial resistant (AR Campylobacter coli isolated from swine reared in the conventional and antimicrobial-free (ABF swine production systems at farm, slaughter and environment. A total of 200 C. coli isolates selected from fecal, environmental, and carcass samples of ABF (n = 100 and conventional (n = 100 swine production systems were typed by multilocus sequence typing (MLST. Sequence data from seven housekeeping genes was analyzed for the identification of allelic profiles, sequence types (STs and clonal complex determination. Phylogenetic trees were generated to establish the relationships between the genotyped isolates. A total of 51 STs were detected including two novel alleles (glnA 424 and glyA 464 and 14 novel STs reported for the first time. The majority of the C. coli isolates belonged to ST-854 (ABF: 31, conventional: 17, and were grouped in clonal complex ST-828 (ABF: 68%, conventional: 66%. The mean genetic diversity (H for the ABF (0.3963+/-0.0806 and conventional (0.4655+/-0.0714 systems were similar. The index of association (I(A(S for the ABF (I(A(S= 0.1513 and conventional (I(A(S = 0.0991 C. coli populations were close to linkage equilibrium, indicative of a freely recombining population. Identical STs were detected between the pigs and their environment both at farm and slaughter. A minimum spanning tree revealed the close clustering of C. coli STs that originated from swine and carcass with those from the environment. In conclusion, our study reveals a genotypic diverse C. coli population that shares a common ancestry in the conventional and ABF swine production systems. This could potentially explain the high prevalence of antimicrobial resistant C. coli in the ABF system in the absence of antimicrobial selection pressure.

  12. Phylogenetic analysis reveals common antimicrobial resistant Campylobacter coli population in antimicrobial-free (ABF) and commercial swine systems.

    Science.gov (United States)

    Quintana-Hayashi, Macarena P; Thakur, Siddhartha

    2012-01-01

    The objective of this study was to compare the population biology of antimicrobial resistant (AR) Campylobacter coli isolated from swine reared in the conventional and antimicrobial-free (ABF) swine production systems at farm, slaughter and environment. A total of 200 C. coli isolates selected from fecal, environmental, and carcass samples of ABF (n = 100) and conventional (n = 100) swine production systems were typed by multilocus sequence typing (MLST). Sequence data from seven housekeeping genes was analyzed for the identification of allelic profiles, sequence types (STs) and clonal complex determination. Phylogenetic trees were generated to establish the relationships between the genotyped isolates. A total of 51 STs were detected including two novel alleles (glnA 424 and glyA 464) and 14 novel STs reported for the first time. The majority of the C. coli isolates belonged to ST-854 (ABF: 31, conventional: 17), and were grouped in clonal complex ST-828 (ABF: 68%, conventional: 66%). The mean genetic diversity (H) for the ABF (0.3963+/-0.0806) and conventional (0.4655+/-0.0714) systems were similar. The index of association (I(A)(S)) for the ABF (I(A)(S)= 0.1513) and conventional (I(A)(S) = 0.0991) C. coli populations were close to linkage equilibrium, indicative of a freely recombining population. Identical STs were detected between the pigs and their environment both at farm and slaughter. A minimum spanning tree revealed the close clustering of C. coli STs that originated from swine and carcass with those from the environment. In conclusion, our study reveals a genotypic diverse C. coli population that shares a common ancestry in the conventional and ABF swine production systems. This could potentially explain the high prevalence of antimicrobial resistant C. coli in the ABF system in the absence of antimicrobial selection pressure. PMID:22984540

  13. 48株流感嗜血杆菌耐药性分析及β-内酰胺酶基因检测%Analysis on antimicrobial resistance and beta-lactamases gene detection of 48 haemophilus influenzae

    Institute of Scientific and Technical Information of China (English)

    桂和翠; 王中新; 沈继录

    2012-01-01

    目的 了解本地区流感嗜血杆菌的分布及耐药性,为指导临床合理用药提供依据.方法 k-B法进行药敏试验,玻片法测定β-内酰胺酶.PCR扩增TEM及ROB型β-内酰胺酶基因.结果 48株流感嗜血杆菌主要分布于呼吸内科和门诊.对复方新诺明、四环素和氨苄西林耐药率分别为62.50%、35.42% 和22 92%;阿莫西林/克拉维酸钾、氨曲南耐药率为12.50%;氨苄西林/舒巴坦、头孢噻肟、头孢拉定、头孢曲松、阿奇霉素、氯霉素耐药率为8.33%;头孢吡肟、头孢呋辛、环丙沙星、左氧氟沙星耐药率为6.25%.哌拉西林/三唑巴坦、亚胺培南敏感率高为100%.10株氨苄西林耐药菌株均产β-内酰胺酶,产酶率为20.83%,且均检测到TEM基因.结论 复方新诺明和四环素已不再适于临床治疗流感嗜血杆菌引起的感染.氨苄西林仍可作为临床经验用药.哌拉西林/三唑巴坦和亚胺培南抗菌活性高,可望作为治疗耐氨苄西林流感嗜血杆菌感染的理想用药.喹诺酮类药物耐药率高,应引起重视.流感嗜血杆菌对氨苄西林耐药的主要机制为产TEM型β-内酰胺酶.%To investigate antimicrobial resistance and genotypes of β-lactamase of in this erea , and guide clinical rational drug use effectively. Methods Kirby-Bauer method was applied for the drug susceptibility test and nitrocefin slide test was used to detect β-lactamase. The genotypes of β-lactamase were detected by PCR. Results A total of 48 strains of haemophilus influenzae were mainly distributed in department of respiratory and outpatient service. The resistant straint to compound sulf-amethoxazole, ampicillin and tetrocycline were 62. 50% , 35. 42% ,22. 92% respectively, the resistant rate to amoxicillin-clavulanic acid, ceftriaxome, aztreonam, ciprofloxa-cin and levofloxacin was 12.50% ,the resistant rate to ampicillin-sulbactam, cefotaxime, ceftazidime, cefuroxime, azithromycin, chlorampheniol was 8. 33% ;the

  14. Role of Antimicrobial Selective Pressure and Secondary Factors on Antimicrobial Resistance Prevalence in Escherichia coli from Food-Producing Animals in Japan

    OpenAIRE

    Harada, Kazuki; Asai, Tetsuo

    2010-01-01

    The use of antimicrobial agents in the veterinary field affects the emergence, prevalence, and dissemination of antimicrobial resistance in bacteria isolated from food-producing animals. To control the emergence, prevalence, and dissemination of antimicrobial resistance, it is necessary to implement appropriate actions based on scientific evidence. In Japan, the Japanese Veterinary Antimicrobial Resistance Monitoring System (JVARM) was established in 1999 to monitor the antimicrobial suscepti...

  15. Resistance of Streptococcus sanguis biofilms to antimicrobial agents

    DEFF Research Database (Denmark)

    Larsen, T; Fiehn, N E

    1996-01-01

    Bacteria living in biofilms as dental plaque on tooth surfaces are generally more resistant to antimicrobial agents than bacteria in batch culture normally used for in vitro susceptibility testing. In order to compare the resistance of free-living and surface-grown oral bacteria, the MIC of Strep......Bacteria living in biofilms as dental plaque on tooth surfaces are generally more resistant to antimicrobial agents than bacteria in batch culture normally used for in vitro susceptibility testing. In order to compare the resistance of free-living and surface-grown oral bacteria, the MIC...... of Streptococcus sanguis 804 and ATCC 10556 to amoxicillin, doxycycline and chlorhexidine was determined by a broth dilution method. Subsequently, S. sanguis biofilms established in an in vitro flow model were perfused with the antimicrobial agents for 48 h at concentrations equal to and up to 500 times the MIC......, and biofilm cell number was determined during this period. The antibiotics at the MIC did not affect the cell number of S. sanguis biofilms compared to the starting point, and only after 48 h at 500 times the MIC were the biofilm bacteria eliminated. At intermediate concentrations biofilm cell number...

  16. Efficacy of triclosan as an antimicrobial hand soap and its potential impact on antimicrobial resistance: a focused review.

    Science.gov (United States)

    Giuliano, Christopher A; Rybak, Michael J

    2015-03-01

    Triclosan is a synthetic biocide found in many household products, including antimicrobial hand soap. Levels of triclosan have been found throughout the environment and in human urine, blood, and even breast milk. Increasing levels of exposure to triclosan have led to concerns over the development of resistance to triclosan and cross-resistance to other antimicrobials. We performed a literature search to assess whether the widespread use of triclosan displays a favorable benefit: risk ratio, defined by evaluation of triclosan's efficacy as an antimicrobial hand soap and its potential effect on the development of antimicrobial resistance. Data from laboratory-based studies regarding the efficacy of triclosan are conflicting, although well-designed studies suggest no significant difference in efficacy over nonantimicrobial soap. In addition, when triclosan was introduced in a community setting, no beneficial effects were observed on the reduction of infections over nonantimicrobial soap. Resistance to triclosan and cross-resistance to antimicrobials have been consistently demonstrated in laboratory settings, although overall resistance rates and cross-resistance rates in the community setting are low. Based on the available evidence, the risk of potential antimicrobial resistance outweighs the benefit of widespread triclosan use in antimicrobial soaps.

  17. Enhancing US-Japan cooperation to combat antimicrobial resistance.

    Science.gov (United States)

    Gerbin, C Sachi

    2014-01-01

    The Global Health Security Agenda (GHSA) is aimed at preventing, detecting, and responding to infectious disease threats. To move toward these goals, the United States has committed to partner with at least 30 countries around the world. One of the objectives of the GHSA includes "[p]reventing the emergence and spread of antimicrobial drug resistant organisms." Antimicrobial resistance (AMR) has become a growing global health security problem, with inappropriate use of antimicrobial medications in humans and animals and a lack of new antimicrobial medications contributing to this problem. While AMR is a growing global concern, working on it regionally can make this multifaceted problem more manageable. The United States and Japan, both world leaders in the life sciences, are close allies that have established cooperative programs in medical research and global health that can be used to work on combating AMR and advance the GHSA. Although the United States and Japan have cooperated on health issues in the past, their cooperation on the growing problem of AMR has been limited. Their existing networks, cooperative programs, and close relationships can and should be used to work on combating this expanding problem.

  18. Ecological aspects of the antimicrobial resistence in bacteria of importance to humn infections

    Directory of Open Access Journals (Sweden)

    Meirelles-Pereira Frederico de

    2002-01-01

    Full Text Available In view of the intimate relationship of humans with coastal lagoons (used for recreation, tourism, water supply, etc., the discharge of domestic effluents may lead to the establishment of routes of dissemination of pathogenic microorganisms, including microorganisms carrying genes for resistance to antimicrobials, through the surrounding human communities. The objective of the present investigation was to relate the presence of antimicrobial-resistant bacteria to the environmental characteristics of three coastal lagoons, comparing the results with those from hospital sewage. Of the lagoons evaluated, two (Geribá and Imboassica receive domestic sewage discharge, and the other (Cabiúnas is still in a natural state. We isolated in a culture medium containing 32 ¼ µg/ml of Cephalothin, fecal coliforms (E. coli, non-fecal coliforms (Klebsiella, Enterobacter, Serratia, and Citrobacter, non-glucose-fermenting Gram-negative bacilli, and Aeromonas sp. In cultures from the hospital drain we found strains showing numerous markers for resistance to most of the 11 antimicrobials tested. On the other hand, in cultures from Cabiúnas and Imboassica lagoons, we found strains showing resistance only to antibiotics frequently observed in non-selective situations (considered as "common" markers. The capacity for dilution in the ecosystem, and salinity appeared related with the occurrence of multi-resistant bacterial strains. The intensity of recent fecal contamination was not shown to be associated with the numbers and types of markers found.

  19. Antimicrobial resistance and clonality in Acinetobacter baumannii

    NARCIS (Netherlands)

    Nemec, Alexandr

    2009-01-01

    The aim of this thesis was to obtain insight into the epidemiology and molecular basis of multidrug resistance of Acinetobacter baumannii at the population level. To this aim a number of studies were performed on strains mainly from the Czech Republic (CR) which have shown in particular that (i) the

  20. First antimicrobial resistance data and genetic characteristics of Neisseria gonorrhoeae isolates from Estonia, 2009–2013

    Directory of Open Access Journals (Sweden)

    D. Golparian

    2014-09-01

    Full Text Available Gonorrhoea is a sexually transmitted infection with major public health implications and Neisseria gonorrhoeae has developed resistance to all antimicrobials introduced for treatment. Enhanced surveillance of antimicrobial resistance in N. gonorrhoeae is crucial globally. This is the first internationally reported antimicrobial resistance data for N. gonorrhoeae from Estonia (44 isolates cultured in 2009–2013. A high prevalence of resistance was observed for azithromycin, ciprofloxacin and tetracycline. One and two isolates with resistance and decreased susceptibility to the last remaining first-line treatment option ceftriaxone, respectively, were identified. It is crucial to implement surveillance of gonococcal antimicrobial resistance (ideally also treatment failures in Estonia.

  1. Antimicrobial drug resistance of Escherichia coli isolated from poultry abattoir workers at risk and broilers on antimicrobials

    Directory of Open Access Journals (Sweden)

    J.W. Oguttu

    2008-05-01

    Full Text Available Antimicrobial usage in food animals increases the prevalence of antimicrobial drug resistance among their enteric bacteria. It has been suggested that this resistance can in turn be transferred to people working with such animals, e.g. abattoir workers. Antimicrobial drug resistance was investigated for Escherichia coli from broilers raised on feed supplemented with antimicrobials, and the people who carry out evisceration, washing and packing of intestines in a high-throughput poultry abattoir in Gauteng, South Africa. Broiler carcasses were sampled from 6 farms, on each of which broilers are produced in a separate 'grow-out cycle'. Per farm, 100 caeca were randomly collected 5 minutes after slaughter and the contents of each were selectively cultured for E. coli. The minimum inhibitory concentration (MIC of each isolate was determined for the following antimicrobials : doxycycline, trimethoprim, sulphamethoxazole, ampicillin, enrofloxacin, fosfomycin, ceftriaxone and nalidixic acid. The same was determined for the faeces of 29 abattoir workers and 28 persons used as controls. The majority of isolates from broilers were resistant, especially to antimicrobials that were used on the farms in the study. Overall median MICs and the number of resistant isolates from abattoir workers (packers plus eviscerators tended to be higher than for the control group. However, no statistically significant differences were observed when the median MICs of antimicrobials used regularly in poultry and percentage resistance were compared, nor could an association between resistance among the enteric E. coli from packers and those from broilers be demonstrated.

  2. Emerging antimicrobial resistance pattern of Helicobacter pylori in central Gujarat

    Directory of Open Access Journals (Sweden)

    H B Pandya

    2014-01-01

    Full Text Available Background: Antimicrobial resistance is a growing problem in H. pylori treatment. The study was intended to evaluate the prevalence of resistance amongst 80 H.pylori isolates cultured from biopsy taken during routine endoscopies in 2008-2011. Materials and Methods: 855 gastro duodenal biopsies were collected and cultured on H.pylori selective medium (containing Brucella agar and Columbia agar (Hi media, with Skirrow′s supplement (antibiotic supplement and 7% human blood cells. H.pylori was isolated from 80 specimens. The antimicrobial susceptibility of H.pylori isolates was carried out by the Kirby Bauer technique against metronidazole (5 µg, clarithromycin (15 µg, ciprofloxacin (5 µg, amoxicillin (10 µg, tetracycline (30 µg, erythromycin (15 µg, levofloxacin (5 µg, and furazolidone (50 µg (Sigma- Aldrich, MO. Results: 83.8% isolates were resistant to metronidazole, 58.8% were resistant to Clarithromycin 72.5% were resistant to Amoxicillin, 50% to Ciprofloxacin and 53.8% to tetracycline. furazolidone, erythromycin and Levofloxacin showed only 13.8% resistance to H.pylori. Multi drug resistance with metronidazole+ clarithromycin+ tetracycline was 85%. For all the drugs Antimicrobial resistance rate was found higher in males compare to females. Metronidazole and amoxicillin resistance was found noteworthy in patients with duodenal ulcer (p = 0.018, gastritis (P = 0.00, and in reflux esophagitis (P = 0.00. clarithromycin and tetracycline resistance was suggestively linked with duodenitis (P = 0.018, while furazolidone, erythromycin and levofloxacin showed excellent sensitivity in patients with duodenitis (P value- 0.018, gastritis (P= 0.00 and reflux esophagitis (P = 0.00. Resistance with metronidazole (P = 0.481, clarithromycin (P= 0.261, amoxicillin (P = 0.276, tetracycline (P = 0.356, ciprofloxacin (P = 0.164 was not correlated well with Age-group and Gender of the patients. Conclusion: A very high percentage of patients were infected

  3. Synthetic RNA silencing in bacteria - antimicrobial discovery and resistance breaking

    Directory of Open Access Journals (Sweden)

    James E.M. Stach

    2011-09-01

    Full Text Available The increasing incidence and prevalence of antibiotic resistance in bacteria threatens the antibiotic miracle. Conventional antimicrobial drug development has failed to replace the armamentarium needed to combat this problem, and novel solutions are urgently required. Here we review both natural and synthetic RNA silencing and its potential to provide new antibacterials through improved target selection, evaluation and screening. Furthermore, we focus on synthetic RNA silencers as a novel class of antibacterials and review their unique properties.

  4. Methodological comparisons for antimicrobial resistance surveillance in feedlot cattle

    OpenAIRE

    Katharine M Benedict; Gow, Sheryl P.; Checkley, Sylvia; Booker, Calvin W.; McAllister, Tim A; Morley, Paul S.

    2013-01-01

    Background The purpose of this study was to objectively compare methodological approaches that might be utilized in designing an antimicrobial resistance (AMR) surveillance program in beef feedlot cattle. Specifically, four separate comparisons were made to investigate their potential impact on estimates for prevalence of AMR. These included investigating potential differences between 2 different susceptibility testing methods (broth microdilution and disc diffusion), between 2 different targ...

  5. Molecular characterization of antimicrobial resistance in enterococci and Escherichia coli isolates from European wild rabbit (Oryctolagus cuniculus).

    Science.gov (United States)

    Silva, Nuno; Igrejas, Gilberto; Figueiredo, Nicholas; Gonçalves, Alexandre; Radhouani, Hajer; Rodrigues, Jorge; Poeta, Patrícia

    2010-09-15

    A total of 44 Escherichia coli and 64 enterococci recovered from 77 intestinal samples of wild European rabbits in Portugal were analyzed for resistance to antimicrobial agents. Resistance in E. coli isolates was observed for ampicillin, tetracycline, sulfamethoxazole/trimethoprim, streptomycin, gentamicin, tobramycin, nalidixic acid, ciprofloxacin and chloramphenicol. None of the E. coli isolates produced extended-spectrum beta-lactamases (ESBLs). The bla(TEM), aadA, aac(3)-II, tet(A) and/or tet(B), and the catA genes were demonstrated in all ampicillin, streptomycin, gentamicin, tetracycline, and chloramphenicol-resistant isolates respectively, and the sul1 and/or sul2 and/or sul3 genes in 4 of 5 sulfamethoxazole/trimethoprim resistant isolates. Of the enterococcal isolates, Enterococcus faecalis was the most prevalent detected species (39 isolates), followed by E. faecium (21 isolates) and E. hirae (4 isolates). More than one-fourth (29.7%) of the isolates were resistant to tetracycline; 20.3% were resistant to erythromycin, 14.1% were resistant to ciprofloxacin and 10.9% were resistant to high-level-kanamycin. Lower level of resistance (quinupristin/dalfopristin and high-level-gentamicin, -streptomycin. No vancomycin-resistance was detected in the enterococci isolates. Resistance genes detected included aac(6')-aph(2''), ant(6)-Ia, tet(M) and/or tet(L) in all gentamicin, streptomycin and tetracycline-resistant isolates respectively. The aph(3')-IIIa gene was detected in 6 of 7 kanamycin-resistant isolates, the erm(B) gene in 11 of 13 erythromycin-resistant isolates and the vat(D) gene in the quinupristin/dalfopristin-resistant E. faecium isolate. This survey showed that faecal bacteria such as E. coli and enterococci of wild rabbits could be a reservoir of antimicrobial resistance genes. PMID:20624632

  6. Antimicrobial (Drug) Resistance: Methicillin-Resistant Staphylococcus aureus (MRSA)

    Science.gov (United States)

    ... Marketing Share this: Main Content Area Methicillin-Resistant Staphylococcus aureus (MRSA) During the past four decades, methicillin-resistant Staphylococcus aureus , or MRSA, has evolved from a controllable ...

  7. [Insect antimicrobial peptides: structures, properties and gene regulation].

    Science.gov (United States)

    Wang, Yi-Peng; Lai, Ren

    2010-02-01

    Insect antimicrobial peptides (AMPs) are an important group of insect innate immunity effectors. Insect AMPs are cationic and contain less than 100 amino acid residues. According to structure, insect AMPs can be divided into a limited number of families. The diverse antimicrobial spectrum of insect AMPs may indicate different modes of action. Research on the model organism Drosophila indicate that insect AMPs gene regulation involves multiple signaling pathways and a large number of signaling molecules.

  8. Intrinsic Antimicrobial Resistance Determinants in the Superbug Pseudomonas aeruginosa

    OpenAIRE

    Murray, Justine L.; Kwon, Taejoon; Marcotte, Edward M.; Whiteley, Marvin

    2015-01-01

    ABSTRACT Antimicrobial-resistant bacteria pose a serious threat in the clinic. This is particularly true for opportunistic pathogens that possess high intrinsic resistance. Though many studies have focused on understanding the acquisition of bacterial resistance upon exposure to antimicrobials, the mechanisms controlling intrinsic resistance are not well understood. In this study, we subjected the model opportunistic superbug Pseudomonas aeruginosa to 14 antimicrobials under highly controlled...

  9. Isolates of Staphylococcus aureus and saprophyticus resistant to antimicrobials isolated from the Lebanese aquatic environment.

    Science.gov (United States)

    Harakeh, Steve; Yassine, Hadi; Hajjar, Shady; El-Fadel, Mutasem

    2006-08-01

    The indiscriminate use of antimicrobials especially in developing countries has evoked serious bacterial resistance and led to the emergence of new and highly resistant strains of bacteria to commonly used antimicrobials. In Lebanon, pollution levels and bacterial infections are increasing at a high rate as a result of inadequate control measures to limit untreated effluent discharges into the sea or freshwater resources. The aim of this study was to isolate and molecularly characterize various Staphylococcus strains isolated from sea water, fresh water, sediments, and crab samples collected from representative communities along the coast of Lebanon. The results on the antimicrobial resistance indicated that the level of resistance of Staphylococcus aureus varied with various antimicrobials tested. The resistance patterns ranged between 45% in freshwater isolates and 54.8% in seawater ones. Fifty one percent of the tested isolates have shown resistance to at least one of the five tested antimicrobials; with seawater isolates exhibiting the highest rates of antimicrobial resistance.

  10. Antimicrobial resistance of zoonotic and commensal bacteria in Europe: the missing link between consumption and resistance in veterinary medicine.

    Science.gov (United States)

    Garcia-Migura, Lourdes; Hendriksen, Rene S; Fraile, Lorenzo; Aarestrup, Frank M

    2014-05-14

    The emergence of resistance in food animals has been associated to the consumption of antimicrobials in veterinary medicine. Consequently, monitoring programs have been designed to monitor the occurrence of antimicrobial resistant bacteria. This study analyses the amount of antimicrobial agents used in nine European countries from 2005 to 2011, and compares by univariate analysis the correlations between consumptions of each of the following antimicrobial classes; tetracycline, penicillins, cephalosporins, quinolones and macrolides. An overview of resistance in zoonotic and commensal bacteria in Europe focusing on Salmonella, Escherichia coli, Campylobacter sp. and Enterococcus sp., during the same period of time based on monitoring programs is also assessed. With the exception of cephalosporins, linear regressions showed strong positive associations between the consumption of the four different antimicrobial classes. Substantial differences between countries were observed in the amount of antimicrobials used to produce 1 kg of meat. Moreover, large variations in proportions of resistant bacteria were reported by the different countries, suggesting differences in veterinary practice. Despite the withdrawn of a specific antimicrobial from "on farm" use, persistence over the years of bacteria resistant to this particular antimicrobial agent, was still observed. There were also differences in trends of resistance associated to specific animal species. In order to correlate the use of antimicrobial agents to the presence of resistance, surveillance of antimicrobial consumption by animal species should be established. Subsequently, intervention strategies could be designed to minimize the occurrence of resistance.

  11. How Can Vaccines Contribute to Solving the Antimicrobial Resistance Problem?

    Science.gov (United States)

    Siber, George R.

    2016-01-01

    ABSTRACT There is a growing appreciation for the role of vaccines in confronting the problem of antimicrobial resistance (AMR). Vaccines can reduce the prevalence of resistance by reducing the need for antimicrobial use and can reduce its impact by reducing the total number of cases. By reducing the number of pathogens that may be responsible for a particular clinical syndrome, vaccines can permit the use of narrower-spectrum antibiotics for empirical therapy. These effects may be amplified by herd immunity, extending protection to unvaccinated persons in the population. Because much selection for resistance is due to selection on bystander members of the normal flora, vaccination can reduce pressure for resistance even in pathogens not included in the vaccine. Some vaccines have had disproportionate effects on drug-resistant lineages within the target species, a benefit that could be more deliberately exploited in vaccine design. We describe the effects of current vaccines in controlling AMR, survey some vaccines in development with the potential to do so further, and discuss strategies to amplify these benefits. We conclude with a discussion of research and policy priorities to more fully enlist vaccines in the battle against AMR. PMID:27273824

  12. How Can Vaccines Contribute to Solving the Antimicrobial Resistance Problem?

    Directory of Open Access Journals (Sweden)

    Marc Lipsitch

    2016-06-01

    Full Text Available There is a growing appreciation for the role of vaccines in confronting the problem of antimicrobial resistance (AMR. Vaccines can reduce the prevalence of resistance by reducing the need for antimicrobial use and can reduce its impact by reducing the total number of cases. By reducing the number of pathogens that may be responsible for a particular clinical syndrome, vaccines can permit the use of narrower-spectrum antibiotics for empirical therapy. These effects may be amplified by herd immunity, extending protection to unvaccinated persons in the population. Because much selection for resistance is due to selection on bystander members of the normal flora, vaccination can reduce pressure for resistance even in pathogens not included in the vaccine. Some vaccines have had disproportionate effects on drug-resistant lineages within the target species, a benefit that could be more deliberately exploited in vaccine design. We describe the effects of current vaccines in controlling AMR, survey some vaccines in development with the potential to do so further, and discuss strategies to amplify these benefits. We conclude with a discussion of research and policy priorities to more fully enlist vaccines in the battle against AMR.

  13. Burkholderia cenocepacia zinc metalloproteases influence resistance to antimicrobial peptides.

    Science.gov (United States)

    Kooi, Cora; Sokol, Pamela A

    2009-09-01

    Burkholderia cenocepacia secretes two zinc-dependent metalloproteases, designated ZmpA and ZmpB. Previously, ZmpA and ZmpB have been shown to cleave several proteins important in host defence. In this study, the ability of ZmpA and ZmpB to digest and inactivate antimicrobial peptides involved in innate immunity was examined. ZmpB but not ZmpA cleaved beta-defensin-1. ZmpA but not ZmpB cleaved the cathelicidin LL-37. Both enzymes cleaved elafin and secretory leukocyte inhibitor, which are antimicrobial peptides as well as neutrophil elastase inhibitors. Both ZmpA and ZmpB cleaved protamine, a fish antimicrobial peptide, and a zmpA zmpB mutant was more sensitive to protamine killing than the parental strain. ZmpA or ZmpB cleavage of elafin inactivated its anti-protease activity. The effect of ZmpA and ZmpB on the neutrophil proteases elastase and cathepsin G was also examined but neither enzyme was active against these host proteases. These studies suggest that ZmpA and ZmpB may influence the resistance of B. cenocepacia to host antimicrobial peptides as well as alter the host protease/anti-protease balance in chronic respiratory infections.

  14. Antimicrobial resistance and virulence profiles of Salmonella isolated from butcher shops in Minas Gerais, Brazil.

    Science.gov (United States)

    Cossi, Marcus Vinícius Coutinho; Burin, Raquel Cristina Konrad; Lopes, Danilo Augusto; Dias, Mariane Rezende; Castilho, Natalia Parma Augusto de; de Arruda Pinto, Paulo Sérgiode; Nero, Luís Augusto

    2013-09-01

    Salmonella can contaminate finished products of butcher shops, mainly through cross-contamination of utensils exposed to raw materials. To identify the main sources of contamination with this foodborne pathogen in four butcher shop environments, surface samples were obtained from employees' hands, cutting boards, knives, floor of the refrigeration room, meat grinders, and meat tenderizers (32 samples per area) and analyzed for Salmonella using the International Organization for Standardization method 6579, with modifications. Suspect isolates were identified by PCR (targeting ompC), and confirmed Salmonella isolates were subjected to pulsed-field gel electrophoresis (after treatment with restriction enzyme XbaI), analyzed for the presence of virulence genes (invA, sefA, and spvC), and screened for resistance to 12 antimicrobials. Salmonella isolates was identified only on cutting boards (five samples) from three butcher shops. Fifteen isolates were confirmed as Salmonella belonging to four pulse types (similarity of 71.1 to 100%). The invA gene was detected in 13 isolates, and the sefA was found in 8 isolates; no isolate carried spvC. All tested isolates were resistant to clindamycin and sensitive to amikacin and cefotaxine, and all isolates were resistant to at least 3 of the 12 antimicrobials tested. The results indicate the importance of cutting boards as a source of Salmonella contamination in butcher shops. The presence of multidrug-resistant Salmonella strains possessing virulence genes highlights the health risks for consumers.

  15. Antimicrobial Resistance and Antimicrobial Use Associated with Laboratory-Confirmed Cases of Campylobacter Infection in Two Health Units in Ontario

    Directory of Open Access Journals (Sweden)

    Anne E Deckert

    2013-01-01

    Full Text Available AIM: A population-based study was conducted over a two-year period in the Perth District (PD and Wellington-Dufferin-Guelph (WDG health units in Ontario to document antimicrobial resistance and antimicrobial use associated with clinical cases of laboratory-confirmed campylobacteriosis.

  16. Comparison of individual and pooled samples for quantification of antimicrobial resistance genes in swine feces by high-throughput qPCR

    DEFF Research Database (Denmark)

    Clasen, Julie; Mellerup, Anders; Olsen, John Elmerdahl;

    2015-01-01

    ® 16 Blood DNA Purification Kit (Promega). DNA concentrations were diluted to 40 ng/μl. The efficiency of the primers was determined using standard curves. Obtained results were normalized with 16S ribosomal DNA. There were large variations in the levels of AMR-genes between individual samples...... and analysis times. The objective of this study was to estimate how many individual fecal samples are needed to pool to get a representative sample for quantification of AMR-genes in a Danish pig herd. 20 individual fecal samples were collected from one section in a Danish pig herd. One to five rectal fecal...... samples were taken from each pen with respect to the number of pigs in the pen. A total of 48 pools were made of increasing number of individual samples. The levels of 9 different AMR-genes were quantified using dynamic qPCR arrays on the BioMark HD system(Fluidigm®).DNA was extracted using the Maxwell...

  17. [Antimicrobial resistance forever? Judicious and appropriate use of antibiotics].

    Science.gov (United States)

    Cagliano, Stefano

    2015-06-01

    This article takes its cue from the original work of sir Alexander Fleming on penicillin, published in the first issue of Recenti Progressi in Medicina in 1946 and reproduced here on the occasion of the approaching 70-year anniversary of the journal. In 1928, at the time when penicillin was discovered, it could not be imagined that bacterial resistance to antibiotics would develop so rapidly: the introduction of every new class of antibiotics has been shortly followed by the emergence of new strains of bacteria resistant to that class. Bacterial resistance to antibiotic treatment is a huge concern. In this respect, an action plan against antimicrobial resistance has been devised in the United States that is targeted for a 50% reduction over the next five years.

  18. Staphylococcus aureus isolated from handmade sweets: Biofilm formation, enterotoxigenicity and antimicrobial resistance.

    Science.gov (United States)

    Kroning, Isabela Schneid; Iglesias, Mariana Almeida; Sehn, Carla Pohl; Valente Gandra, Tatiane Kuka; Mata, Marcia Magalhães; da Silva, Wladimir Padilha

    2016-09-01

    Staphylococcus aureus is the second most important pathogen involved in foodborne outbreaks in Brazil. Because of their widespread distribution and biofilm forming ability, handmade sweets are easily contaminated with S. aureus. The aim of this study was to isolate and identify coagulase-positive staphylococci (CPS) from handmade sweets produced in Pelotas City/Brazil. The virulence potential was checked by evaluating the presence of the staphylococcal enterotoxin genes, icaA and icaD genes, the biofilm forming potential and antimicrobial resistance of the isolates. It was find just S. aureus among the CPS isolates. All the S. aureus isolates had biofilm forming ability on stainless steel and more than half of them on polystyrene surfaces. The majority of the isolates carried the icaA (66.6%) and icaD (58.4%) genes and some of them had the genes encoding enterotoxins A (33.4%) and B (16.6%). Furthermore, the majority of the isolates (83%) were resistant to at least one of the tested antimicrobials and multidrug resistance was observed in 8.4% of the isolates. The isolates had virulence potential, and half of them were enterotoxigenic. In addition, the ability of all the isolates to produce biofilms highlights the danger posed by these potentially virulent microorganisms persisting in food manufacturing environments. PMID:27217365

  19. Prevalence and Antimicrobial Resistance of Vibrio spp. in Retail and Farm Shrimps in Ecuador.

    Science.gov (United States)

    Sperling, L; Alter, T; Huehn, S

    2015-11-01

    The aim of this study was to investigate the prevalence of Vibrio spp. in shrimp at retail and in shrimp farms in Ecuador and to determine the antimicrobial agent resistance patterns of farm isolates. The presence of genes linked to early mortality syndrome (EMS) or acute hepatopancreatic necrosis disease (AHPND) also was evaluated. Vibrio spp. were isolated from retail shrimps in Cuenca, Ecuador, and farm shrimps originating from provinces El Oro and Guayas, Ecuador. A total of 229 shrimp samples were collected, of which 71 originated from retail markets in Cuenca and 158 came from shrimp farms. Overall, 219 (95.6%) samples tested positive for Vibrio spp. Vibrio parahaemolyticus (80.8%) was the most common species detected, followed by Vibrio alginolyticus (50.2%), Vibrio cholerae (11.3%), and Vibrio vulnificus (3.5%). None of the V. parahaemolyticus isolates carried the virulence-associated tdh and trh genes. In V. parahaemolyticus shrimp farm isolates, high resistance was found to ampicillin (92.2%), and intermediate resistance was found to tetracycline (51.3%) and amikacin (22.1%). Of the V. parahaemolyticus strains, 68 were resistant to at least three antimicrobial agents, and 2 were resistant to seven antimicrobial agents simultaneously. Up to 18 resistant isolates were found for V. alginolyticus, whereas V. vulnificus and V. cholerae isolates were more susceptible. None of the V. parahaemolyticus isolates carried the EMS-AHPND plasmid. The results of this study revealed the ubiquitous occurrence of Vibrio spp. in shrimps at retail and on shrimp farms in Ecuador.

  20. Prevalence and Antimicrobial Resistance of Vibrio spp. in Retail and Farm Shrimps in Ecuador.

    Science.gov (United States)

    Sperling, L; Alter, T; Huehn, S

    2015-11-01

    The aim of this study was to investigate the prevalence of Vibrio spp. in shrimp at retail and in shrimp farms in Ecuador and to determine the antimicrobial agent resistance patterns of farm isolates. The presence of genes linked to early mortality syndrome (EMS) or acute hepatopancreatic necrosis disease (AHPND) also was evaluated. Vibrio spp. were isolated from retail shrimps in Cuenca, Ecuador, and farm shrimps originating from provinces El Oro and Guayas, Ecuador. A total of 229 shrimp samples were collected, of which 71 originated from retail markets in Cuenca and 158 came from shrimp farms. Overall, 219 (95.6%) samples tested positive for Vibrio spp. Vibrio parahaemolyticus (80.8%) was the most common species detected, followed by Vibrio alginolyticus (50.2%), Vibrio cholerae (11.3%), and Vibrio vulnificus (3.5%). None of the V. parahaemolyticus isolates carried the virulence-associated tdh and trh genes. In V. parahaemolyticus shrimp farm isolates, high resistance was found to ampicillin (92.2%), and intermediate resistance was found to tetracycline (51.3%) and amikacin (22.1%). Of the V. parahaemolyticus strains, 68 were resistant to at least three antimicrobial agents, and 2 were resistant to seven antimicrobial agents simultaneously. Up to 18 resistant isolates were found for V. alginolyticus, whereas V. vulnificus and V. cholerae isolates were more susceptible. None of the V. parahaemolyticus isolates carried the EMS-AHPND plasmid. The results of this study revealed the ubiquitous occurrence of Vibrio spp. in shrimps at retail and on shrimp farms in Ecuador. PMID:26555534

  1. Presence of antimicrobial resistance in coliform bacteria from hatching broiler eggs with emphasis on ESBL/AmpC-producing bacteria.

    Science.gov (United States)

    Mezhoud, H; Chantziaras, I; Iguer-Ouada, M; Moula, N; Garmyn, A; Martel, A; Touati, A; Smet, A; Haesebrouck, F; Boyen, F

    2016-08-01

    Antimicrobial resistance is recognized as one of the most important global health challenges. Broilers are an important reservoir of antimicrobial resistant bacteria in general and, more particularly, extended-spectrum β-lactamases (ESBL)/AmpC-producing Enterobacteriaceae. Since contamination of 1-day-old chicks is a potential risk factor for the introduction of antimicrobial resistant Enterobacteriaceae in the broiler production chain, the presence of antimicrobial resistant coliform bacteria in broiler hatching eggs was explored in the present study. Samples from 186 hatching eggs, collected from 11 broiler breeder farms, were inoculated on MacConkey agar with or without ceftiofur and investigated for the presence of antimicrobial resistant lactose-positive Enterobacteriaceae, particularly, ESBL/AmpC-producers. Escherichia coli and Enterobacter cloacae were obtained from the eggshells in 10 out of 11 (10/11) sampled farms. The majority of the isolates were recovered from crushed eggshells after external decontamination suggesting that these bacteria are concealed from the disinfectants in the egg shell pores. Antimicrobial resistance testing revealed that approximately 30% of the isolates showed resistance to ampicillin, tetracycline, trimethoprim and sulphonamides, while the majority of isolates were susceptible to amoxicillin-clavulanic acid, nitrofurantoin, aminoglycosides, florfenicol, neomycin and apramycin. Resistance to extended-spectrum cephalosporins was detected in eight Enterobacteriaceae isolates from five different broiler breeder farms. The ESBL phenotype was confirmed by the double disk synergy test and blaSHV-12, blaTEM-52 and blaACT-39 resistance genes were detected by PCR. This report is the first to present broiler hatching eggs as carriers and a potential source of ESBL/AmpC-producing Enterobacteriaceae for broiler chicks.

  2. Evaluation of antimicrobial resistance and virulence of enterococci from equipment surfaces, raw materials, and traditional cheeses.

    Science.gov (United States)

    Gaglio, Raimondo; Couto, Natacha; Marques, Cátia; de Fatima Silva Lopes, Maria; Moschetti, Giancarlo; Pomba, Constança; Settanni, Luca

    2016-11-01

    Forty enterococci isolated along the production chains of three traditional cheeses (PDO Pecorino Siciliano, PDO Vastedda della Valle del Belìce, and Caciocavallo Palermitano) made in Sicily (southern Italy) were studied for the assessment of their antibiotic resistance and virulence by a combined phenotypic/genotypic approach. A total of 31 Enterococcus displayed resistance to at least one or more of the antimicrobials tested. The strains exhibited high percentages of resistance to erythromycin (52.5%), ciprofloxacin (35.0%), quinupristin-dalfopristin (20.0%), tetracycline (17.5%), and high-level streptomycin (5.0%). The presence of tet(M), cat(pC221), and aadE genes for resistance to tetracycline, chloramphenicol, and streptomycin, respectively, was registered in all strains with resistance phenotype. The erm(B) gene was not detected in any erythromycin-resistant strain. The Enterococcus strains were further tested by PCR for the presence of virulence genes, namely, gelE, asa1, efaA, ace, and esp. Twenty strains were positive for all virulence genes tested. Among the enterococci isolated from final cheeses, three strains (representing 33.3% of total cheese strains) were sensible to all antimicrobials tested and did not carry any virulence factor. Although this study confirmed that the majority of dairy enterococci are vectors for the dissemination of antimicrobial resistance and virulence genes, only two strains showed a high resistance to aminoglycosides, commonly administered to combat enterococci responsible for human infections. Furthermore, the presence of the strains E. casseliflavus FMAC163, E. durans FMAC134B, and E. faecium PON94 without risk determinants, found at dominating levels over the Enterococcus populations in the processed products, stimulates further investigations for their future applications in cheese making. All strains devoid of the undesired traits were isolated from stretched cheeses. Thus, this cheese typology represents an

  3. Antimicrobial resistance profiling and molecular subtyping of Campylobacter spp. from processed turkey

    Directory of Open Access Journals (Sweden)

    Sherwood Julie S

    2009-09-01

    Full Text Available Abstract Background Campylobacter is a major cause of human disease worldwide and poultry are identified as a significant source of this pathogen. Most disease in humans is associated with the consumption of contaminated poultry or cross-contamination with other foods. The primary drugs of choice for treatment of human campylobacteriosis include erythromycin and ciprofloxacin. In this study, we investigated the prevalence of resistance to erythromycin and ciprofloxacin in Campylobacter isolates recovered from turkey carcasses at two processing plants in the Upper Midwest US. Further analysis of a subset of isolates was carried out to assess resistance and genotype profiles. Results Campylobacter isolates from plant A (n = 439; including 196 C. coli and 217 C. jejuni and plant B (n = 362, including 281 C. coli and 62 C. jejuni were tested for susceptibility to ciprofloxacin and erythromycin using agar dilution. C. coli were more frequently resistant than C. jejuni in both plants, including resistance to ciprofloxacin (28% of C. jejuni and 63% of C. coli, plant B; and 11% of C. coli, plant A. Erythromycin resistance was low among C. jejuni (0% plant A and 0.3% plant B compared to C. coli (41%, plant A and 17%, plant B. One hundred resistant and susceptible isolates were selected for additional antimicrobial susceptibility testing, restriction fragment length polymorphism analysis of the flaA gene (fla typing, and pulsed-field gel electrophoresis (PFGE. Fla-PFGE types obtained (n = 37 were associated with a specific plant with the exception of one type that was isolated from both plants. C. coli isolates (n = 65 were grouped into 20 types, while C. jejuni isolates (n = 35 were grouped into 17 types. Most isolates with identical fla-PFGE patterns shared identical or very similar antimicrobial resistance profiles. PFGE alone and composite analysis using fla-PFGE with resistance profiles separated C. jejuni and C. coli into distinct groups. Conclusion

  4. Prevalence of multi-antimicrobial-agent resistant, shiga toxin and enterotoxin producing Escherichia coli in surface waters of river Ganga.

    Science.gov (United States)

    Ram, Siya; Vajpayee, Poornima; Shanker, Rishi

    2007-11-01

    The consumption of polluted surface water for domestic and recreational purposes by large populations in developing nations is a major cause of diarrheal disease related mortality. The river Ganga and its tributaries meet 40% of the water requirement for drinking and irrigation in India. In this study, Escherichia coli isolates (n=75) of the river Ganga water were investigated for resistance to antimicrobial agents (n=15) and virulence genes specific to shiga toxin (STEC) and enterotoxin producing E. coli (ETEC). E. coli isolates from the river Ganga water exhibit resistance to multiple antimicrobial agents. The distribution of antimicrobial agent resistance in E. colivaries significantly (chi2: 81.28 at df = 24, p river Ganga water poses increased risk of infections in the human population.

  5. Prevalence of multi-antimicrobial-agent resistant, shiga toxin and enterotoxin producing Escherichia coli in surface waters of river Ganga.

    Science.gov (United States)

    Ram, Siya; Vajpayee, Poornima; Shanker, Rishi

    2007-11-01

    The consumption of polluted surface water for domestic and recreational purposes by large populations in developing nations is a major cause of diarrheal disease related mortality. The river Ganga and its tributaries meet 40% of the water requirement for drinking and irrigation in India. In this study, Escherichia coli isolates (n=75) of the river Ganga water were investigated for resistance to antimicrobial agents (n=15) and virulence genes specific to shiga toxin (STEC) and enterotoxin producing E. coli (ETEC). E. coli isolates from the river Ganga water exhibit resistance to multiple antimicrobial agents. The distribution of antimicrobial agent resistance in E. colivaries significantly (chi2: 81.28 at df = 24, p river Ganga water poses increased risk of infections in the human population. PMID:18044515

  6. Anatomical Distribution and Genetic Relatedness of Antimicrobial Resistant E. coli from Healthy Companion Animals

    Science.gov (United States)

    Aims: Escherichia coli have been targeted for studying antimicrobial resistance in companion animals due to opportunistic infections and as a surrogate for resistance patterns in zoonotic organisms. The aim of our study examined antimicrobial resistance in E. coli isolated from various anatomical ...

  7. [Ecology of antimicrobial resistance: Special aspects of extended-spectrum β-lactamases].

    Science.gov (United States)

    Käsbohrer, A

    2015-11-01

    Extended-spectrum β-lactamase (ESBL) producing Enterobacteriaceae were detected shortly after the introduction of broad spectrum cephalosporins in hospitals. Today, they are prevalent in the community, in animals, foods, and the environment. Many factors contribute to the broad distribution, especially the usage of antimicrobials in humans and animals, and due to multiple resistances, not only the usage of β-lactams and cephalosporins.This broad distribution of ESBLs cannot be fully explained by clonal spread of successful strains. Horizontal transmission of resistance genes, located on transmissible elements, probably plays a much greater role. This gene transfer also enables new combinations of resistance genes which causes therapeutic problems.The complex interactions make it difficult to estimate the relative contribution of the different sources. Resistance genes are broadly distributed in humans, animals, and the environment and the distribution pattern seems to become more similar. It is also evident that two major transmission pathways have to be considered, human-to-human transmission, frequently in hospitals and the exchange of resistance genes between humans, animals, food, and the environment. For the latter, the transfer can go in both directions.Further studies are necessary to understand the pathways between the different reservoirs, the bacterial concentration needed, and the factors having an impact on colonization and transmission. Multiple measures on both the human and veterinary side have to complement each other and interact. A One Health approach needs to be developed and rigorously established. PMID:26482079

  8. Antimicrobial growth promoter ban and resistance to macrolides and vancomycin in enterococci from pigs

    DEFF Research Database (Denmark)

    Boerlin, P.; Wissing, A.; Aarestrup, Frank Møller;

    2001-01-01

    Ninety-six enterococcus isolates from fecal samples of pigs receiving tylosin as an antimicrobial growth promoter and 59 isolates obtained in the same farms 5 to 6 months after the ban of antimicrobial growth promoters in Switzerland were tested for susceptibility to nine antimicrobial agents. A ....... A clear decrease in resistance to macrolides, lincosamides, and tetracycline was visible after the ban. Vancomycin-resistant Enterococcus faecium belonged to the same clonal lineage as vancomycin-resistant isolates previously isolated from Danish pigs....

  9. Antimicrobial susceptibility/resistance and molecular epidemiological characteristics of Neisseria gonorrhoeae in 2009 in Belarus.

    Science.gov (United States)

    Glazkova, Slavyana; Golparian, Daniel; Titov, Leonid; Pankratova, Nataliya; Suhabokava, Nataliya; Shimanskaya, Irina; Domeika, Marius; Unemo, Magnus

    2011-08-01

    Increased antimicrobial resistance (AMR) in Neisseria gonorrhoeae is a global concern, and ultimately gonorrhoea may become untreatable. Nonetheless, AMR data from East-Europe are scarce beyond Russia, and no AMR data or other characteristics of gonococci have been reported from Belarus for more than 20 years. The aim was to describe the prevalence of AMR, and report molecular epidemiological characteristics of gonococci circulating in 2009 in Belarus. In a sample of 80 isolates, resistance prevalences to antimicrobials used for gonorrhoea treatment in Belarus were: Ceftriaxone 0%, spectinomycin 0%, azithromycin 17.3%, tetracycline 25.9%, ciprofloxacin 34.6% and erythromycin 59.2%. The isolates displayed no penA mosaic alleles, 38 porB gene sequences and 35 N. gonorrhoeae multiantigen sequence types, of which 20 have not been described before worldwide. Due to the high levels of antimicrobial resistance, only ceftriaxone and spectinomycin can be recommended for empirical treatment of gonorrhoea in Belarus according to WHO recommendations. Continuous gonococcal AMR surveillance in Eastern Europe is crucial. This is now initiated in Belarus using WHO protocols.

  10. Cultivable Bacterial Microbiota of Northern Bobwhite (Colinus virginianus): A New Reservoir of Antimicrobial Resistance?

    Science.gov (United States)

    Su, Hongwen; McKelvey, Jessica; Rollins, Dale; Zhang, Michael; Brightsmith, Donald J.; Derr, James; Zhang, Shuping

    2014-01-01

    The northern bobwhite (Colinus virginianus) is an ecologically and economically important avian species. At the present time, little is known about the microbial communities associated with these birds. As the first step to create a quail microbiology knowledge base, the current study conducted an inventory of cultivable quail tracheal, crop, cecal, and cloacal microbiota and associated antimicrobial resistance using a combined bacteriology and DNA sequencing approach. A total of 414 morphologically unique bacterial colonies were selected from nonselective aerobic and anaerobic cultures, as well as selective and enrichment cultures. Analysis of the first 500-bp 16S rRNA gene sequences in conjunction with biochemical identifications revealed 190 non-redundant species-level taxonomic units, representing 160 known bacterial species and 30 novel species. The bacterial species were classified into 4 phyla, 14 orders, 37 families, and 59 or more genera. Firmicutes was the most commonly encountered phylum (57%) followed by Actinobacteria (24%), Proteobacteria (17%) and Bacteroidetes (0.02%). Extensive diversity in the species composition of quail microbiota was observed among individual birds and anatomical locations. Quail microbiota harbored several opportunistic pathogens, such as E. coli and Ps. aeruginosa, as well as human commensal organisms, including Neisseria species. Phenotypic characterization of selected bacterial species demonstrated a high prevalence of resistance to the following classes of antimicrobials: phenicol, macrolide, lincosamide, quinolone, and sulphate. Data from the current investigation warrant further investigation on the source, transmission, pathology, and control of antimicrobial resistance in wild quail populations. PMID:24937705

  11. Cultivable bacterial microbiota of northern bobwhite (Colinus virginianus: a new reservoir of antimicrobial resistance?

    Directory of Open Access Journals (Sweden)

    Hongwen Su

    Full Text Available The northern bobwhite (Colinus virginianus is an ecologically and economically important avian species. At the present time, little is known about the microbial communities associated with these birds. As the first step to create a quail microbiology knowledge base, the current study conducted an inventory of cultivable quail tracheal, crop, cecal, and cloacal microbiota and associated antimicrobial resistance using a combined bacteriology and DNA sequencing approach. A total of 414 morphologically unique bacterial colonies were selected from nonselective aerobic and anaerobic cultures, as well as selective and enrichment cultures. Analysis of the first 500-bp 16S rRNA gene sequences in conjunction with biochemical identifications revealed 190 non-redundant species-level taxonomic units, representing 160 known bacterial species and 30 novel species. The bacterial species were classified into 4 phyla, 14 orders, 37 families, and 59 or more genera. Firmicutes was the most commonly encountered phylum (57% followed by Actinobacteria (24%, Proteobacteria (17% and Bacteroidetes (0.02%. Extensive diversity in the species composition of quail microbiota was observed among individual birds and anatomical locations. Quail microbiota harbored several opportunistic pathogens, such as E. coli and Ps. aeruginosa, as well as human commensal organisms, including Neisseria species. Phenotypic characterization of selected bacterial species demonstrated a high prevalence of resistance to the following classes of antimicrobials: phenicol, macrolide, lincosamide, quinolone, and sulphate. Data from the current investigation warrant further investigation on the source, transmission, pathology, and control of antimicrobial resistance in wild quail populations.

  12. Occurrence and antimicrobial resistance of Staphylococcus aureus in bulk tank milk and milk filters

    Directory of Open Access Journals (Sweden)

    Kateřina Bogdanovičová

    2014-02-01

    Full Text Available This work is focused on the monitoring of Staphylococcus aureus prevalence in raw milk and milk filters, its antibiotic resistance and detection of methicillin resistant Staphylococcus aureus (MRSA. Samples of raw cow´s milk and milk filters were collected in the period from 2012 till 2014, from 50 dairy farms in the Czech Republic. The total of 261 samples (164 samples of raw milk and 97 milk filters were cultivated on Baird-Parker agar. Both the typical and atypical colonies were examined by plasmacoagulase test and PCR method was used for detection of species specific fragment SA442 and mecA gene. Standard disk diffusion method was used to determinate resistance to antimicrobial agents. The bacterium Staphylococcus aureus was detected on 25 farms (50%. The antimicrobial resistance showed differences between the farms. Total of 58 samples were positive for Staphylococcus aureus, of which were 37 (14.2% isolated from raw milk samples and 21 (8.1% from milk filters. From these samples we isolated 62 Staphylococcus aureus strains, 41 isolates bacteria S. aureus from raw milk (66.1% and 21 isolates S. aureus from milk filters (33.9%. The presence of antibiotic resistance in Staphylococcus aureus isolates was low, most of them were resistant to amoxicilin. According to the results obtained by the PCR method for the methicillin - resistant S. aureus (MRSA, the mecA gene was present in 6 strains (9.7%, 4 isolates obtained from milk samples (6.5% and 2 isolates from milk filters (3.2%.  These isolates can be considered as a possible source of resistance genes, which can be spread through the food chain. Nowadays, a globally unfavourable increasing trend of prevalence of methicillin resistant staphylococci strains especially Staphylococcus aureus is being observed worldwide. The improper hygiene and poor farm management practices contributed to the presence of S. aureus in the milk. This may have contributed to the high level of S. aureus isolated

  13. Common phenotypic and genotypic antimicrobial resistance patterns found in a case study of multiresistant E. coli from cohabitant pets, humans, and household surfaces.

    Science.gov (United States)

    Martins, Liliana Raquel Leite; Pina, Susana Maria Rocha; Simões, Romeo Luís Rocha; de Matos, Augusto José Ferreira; Rodrigues, Pedro; da Costa, Paulo Martins Rodrigues

    2013-01-01

    The objective of the study described in this article was to characterize the antimicrobial resistance profiles among E. coli strains isolated from cohabitant pets and humans, evaluating the concurrent colonization of pets, owners, and home surfaces by bacteria carrying the same antimicrobial-resistant genes. The authors also intended to assess whether household surfaces and objects could contribute to the within-household antimicrobial-resistant gene diffusion between human and animal cohabitants. A total of 124 E. coli strains were isolated displaying 24 different phenotypic patterns with a remarkable percentage of multiresistant ones. The same resistance patterns were isolated from the dog's urine, mouth, the laundry floor, the refrigerator door, and the dog's food bowl. Some other multiresistant phenotypes, as long as resistant genes, were found repeatedly in different inhabitants and surfaces of the house. Direct, close contact between all the cohabitants and the touch of contaminated household surfaces and objects could be an explanation for these observations. PMID:23397653

  14. Influence of a non-hospital medical care facility on antimicrobial resistance in wastewater.

    Directory of Open Access Journals (Sweden)

    Mathias Bäumlisberger

    Full Text Available The global widespread use of antimicrobials and accompanying increase in resistant bacterial strains is of major public health concern. Wastewater systems and wastewater treatment plants are considered a niche for antibiotic resistance genes (ARGs, with diverse microbial communities facilitating ARG transfer via mobile genetic element (MGE. In contrast to hospital sewage, wastewater from other health care facilities is still poorly investigated. At the instance of a nursing home located in south-west Germany, in the present study, shotgun metagenomics was used to investigate the impact on wastewater of samples collected up- and down-stream in different seasons. Microbial composition, ARGs and MGEs were analyzed using different annotation approaches with various databases, including Antibiotic Resistance Ontologies (ARO, integrons and plasmids. Our analysis identified seasonal differences in microbial communities and abundance of ARG and MGE between samples from different seasons. However, no obvious differences were detected between up- and downstream samples. The results suggest that, in contrast to hospitals, sewage from the nursing home does not have a major impact on ARG or MGE in wastewater, presumably due to much less intense antimicrobial usage. Possible limitations of metagenomic studies using high-throughput sequencing for detection of genes that seemingly confer antibiotic resistance are discussed.

  15. In vitro antimicrobial activity of linezolid tested against vancomycin-resistant enterococci isolated in Brazilian hospitals

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    Reis Adriana O.

    2001-01-01

    Full Text Available The emergence of vancomycin-resistant enterococci (VRE has been described recently in Brazil. This is in contrast to the USA and Europe, where the VRE appeared in the late 1980s. The progressive increase in VRE isolation poses important problems in the antimicrobial therapy of nosocomial infections. Treatment options and effective antimicrobial agents for VRE are often limited and the possibility of transfer of vancomycin genes to other Gram-positive microorganisms continues. In the search for antimicrobial agents for multiresistant Gram-positive cocci, compounds such as linezolid and quinupristin/dalfopristin have been evaluated. The present study was conducted to evaluate the in vitro activity of the oxazolidinone linezolid and 10 other antimicrobial agents, including quinupristin-dalfopristin, against multiresistant enterococci isolated in Brazilian hospitals. Thirty-three vancomycin resistant isolates (17 Enterococcus faecium and 16 E. faecalis, were analyzed. Strains were isolated from patients at São Paulo Hospital, Oswaldo Cruz Hospital, Hospital do Servidor Público Estadual, Santa Marcelina Hospital, Santa Casa de Misericórdia de São Paulo, and Hospital de Clínicas do Paraná. The samples were tested by a broth microdilution method following the National Committee for Clinical Laboratory Standards (NCCLS recommendations. All isolates were molecular typed using pulsed-field gel electrophoresis (PFGE. Linezolid was the most active compound against these multiresistant enterococci, showing 100% inhibition at the susceptible breakpoints. Quinupristin/dalfopristin and teicoplanin showed poor activity against both species. The molecular typing results suggest that there has been interhospital spread of vancomycin resistant E. faecium and E. faecalis among Brazilian hospitals. The results of this study indicate that linezolid is an appropriate therapeutic option for the treatment of vancomycin-resistant enterococci infections in Brazil.

  16. Evidence-based policy for controlling antimicrobial resistance in the food chain in Denmark

    DEFF Research Database (Denmark)

    Wielinga, Pieter; Jensen, Vibeke Frøkjær; Aarestrup, Frank Møller;

    2014-01-01

    Emergence of antimicrobial resistance (AMR) in the animal reservoir forms a risk for human health. The use of antimicrobials in animals is the major cause of development of AMR in animals. In the 1990s, the use of antimicrobials in animals, particularly as a growth promoter, led to alarming level...

  17. Relationship between the severity of acne vulgaris and antimicrobial resistance of bacteria isolated from acne lesions in a hospital in Japan.

    Science.gov (United States)

    Nakase, Keisuke; Nakaminami, Hidemasa; Takenaka, Yuko; Hayashi, Nobukazu; Kawashima, Makoto; Noguchi, Norihisa

    2014-05-01

    Propionibacterium acnes and Staphylococcus epidermidis are normal skin inhabitants that are frequently isolated from lesions caused by acne, and these micro-organisms are considered to contribute to the inflammation of acne. In the present study, we examined the antimicrobial susceptibilities and resistance mechanisms of P. acnes and S. epidermidis isolated from patients with acne vulgaris in a university hospital in Japan from 2009 to 2010. Additionally, we analysed the relationship between the antimicrobial resistance of P. acnes and the severity of acne vulgaris. Some P. acnes strains (18.8 %; 13/69) were resistant to clindamycin. All strains had a mutation in the 23S rRNA gene, except for one strain that expressed erm(X) encoding a 23S rRNA methylase. Tetracycline-resistant P. acnes strains were found to represent 4.3 % (3/69) of the strains, and this resistance was caused by a mutation in the 16S rRNA gene. Furthermore, three strains with reduced susceptibility to nadifloxacin (MIC = 16 µg ml(-1)) were detected. When analysing the correlation between the antimicrobial resistance of P. acnes and S. epidermidis, more than 80 % of the patients who carried clindamycin-resistant P. acnes also carried clindamycin-resistant S. epidermidis. However, no epidemic strain that exhibited antimicrobial resistance was detected in the P. acnes strains when analysed by PFGE. Therefore, our results suggest that the antimicrobial resistance of P. acnes is closely related to antimicrobial therapy. Additionally, those P. acnes strains tended to be frequently found in severe acne patients rather than in mild acne patients. Consequently, the data support a relationship between using antimicrobial agents and the emergence of antimicrobial resistance.

  18. Resistance to antimicrobials and acid and bile tolerance of Bacillus spp isolated from Bikalga, fermented seeds of Hibiscus sabdariffa

    OpenAIRE

    Compaore, Clarisse S.; Jensen, Lars Bogø; Diawara, Brehima; Ouedraogo, Georges A.; Jakobsen, Mogens; Ouoba, Labia I. I.

    2013-01-01

    In the aim of selecting starter cultures, thirteen species of Bacillus spp. including six Bacillus subtilis ssp. subtilis, four Bacillus licheniformis and three Bacillus amyloliquefaciens ssp. plantarum isolated from traditional Bikalga were investigated. The study included, for all isolates, genes, determination of minimal inhibitory concentration (MIC) for 24 antimicrobials and detection of resistance by PCR using specific primers. The isolates were also examined for their resistance to pH ...

  19. Surveillance of antimicrobial resistance in Escherichia coli strains isolated from pigs at Spanish slaughterhouses.

    Science.gov (United States)

    Teshager, T; Herrero, I A; Porrero, M C; Garde, J; Moreno, M A; Domínguez, L

    2000-07-01

    Antimicrobial resistance can make the efficient treatment of bacterial infections in humans and animals more difficult. Antimicrobial use in food animals may be one of the factors contributing to resistance. The Spanish surveillance network VAV has established a baseline of antimicrobial resistance in Escherichia coli strains from healthy pigs. Minimum inhibitory concentration and patterns of resistance to antimicrobials used in animals and humans were determined for 205 faecal strains isolated in a sampling frame of four slaughterhouses in Spain from 220 pigs in 1998. Higher levels of resistance were seen against antimicrobial agents authorised for use in food animals especially tetracycline, sulphonamides, trimethoprim and amoxycillin. All isolates were susceptible to antimicrobials employed mainly in humans such as ceftazidime, cefotaxime, imipenem, aztreonam and amikacin.

  20. Risk assessment of antimicrobial usage in Danish pig production on the human exposure to antimicrobial resistant bacteria from pork

    DEFF Research Database (Denmark)

    Struve, Tina

    During the last decades, bacteria with resistance to all commonly used antimicrobial agents have been detected, thereby posing a major threat to public health. In worst case, infections with resistant bacteria can lead to treatment failure and death of humans. The evolution of bacteria resistant...... to antimicrobials are influenced by the use of antimicrobial agents, and the prudence of antimicrobial use have been emphasized since the Swann report in 1969 recommended that antibiotics used in human medicine should not be used as growth promoters in food-producing animals. In 2007, the World Health Organisation...... was investigated using selective agar plates supplemented with ceftriaxone. The occurrence of ESC producing E. coli was used as the outcome in the data analysis, where the effect of using cephalosporins, extended spectrum penicillins and tetracyclines was estimated using regression analysis. In Objective 2...

  1. Diversity of Antimicrobial Resistance and Virulence Determinants in Pseudomonas aeruginosa Associated with Fresh Vegetables

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    Kashina Allydice-Francis

    2012-01-01

    Full Text Available With the increased focus on healthy eating and consuming raw vegetables, this study assessed the extent of contamination of fresh vegetables by Pseudomonas aeruginosa in Jamaica and examined the antibiotic susceptibility profiles and the presence of various virulence associated determinants of P. aeruginosa. Analyses indicated that vegetables from retail markets and supermarkets were widely contaminated by P. aeruginosa; produce from markets were more frequently contaminated, but the difference was not significant. Lettuce and carrots were the most frequently contaminated vegetables, while tomatoes were the least. Pigment production (Pyoverdine, pyocyanin, pyomelanin and pyorubin, fluorescein and alginate were common in these isolates. Imipenem, gentamicin and ciprofloxacin were the most inhibitory antimicrobial agents. However, isolates were resistant or showed reduced susceptibility to ampicillin, chloramphenicol, sulphamethoxazole/trimethoprim and aztreonam, and up to 35% of the isolates were resistant to four antimicrobial agents. As many as 30% of the isolates were positive for the fpv1 gene, and 13% had multiple genes. Sixty-four percent of the isolates harboured an exoenzyme gene (exoS, exoT, exoU or exoY, and multiple exo genes were common. We conclude that P. aeruginosa is a major contaminant of fresh vegetables, which might be a source of infection for susceptible persons within the community.

  2. Antimicrobial-resistant and ESBL-producing Escherichia coli in different ecological niches in Bangladesh

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    Mahmudur Rashid

    2015-07-01

    Full Text Available Introduction: The rapid and wide-scale environmental spread of multidrug-resistant bacteria in different ecosystems has become a serious issue in recent years. Objectives: To investigate the epidemiology of antimicrobial resistance and extended spectrum beta-lactamase (ESBL in Bangladeshi wild birds and aquatic environments, samples were taken from Open Bill Stork (Anastomus oscitans (OBS and the nearby water sources. Methods: Water and fresh fecal samples were collected from several locations. All samples were processed and cultured for Escherichia coli and tested for antibiotic susceptibility against commonly used antibiotics. ESBL producers were characterized at genotypic level using polymerase chain reaction (PCR, sequencing, multilocus sequence typing, and rep-PCR. Results and discussion: A total of 76 E. coli isolates from the 170 OBS and 8 E. coli isolates from three river sources were isolated. In total, 29% of E. coli isolated from OBS and all of the E. coli isolated from water sources were resistant to at least one of the tested antimicrobials. Resistant phenotypes were observed with all antimicrobials except tigecycline, gentamicin, imipenem, and chloramphenicol. Multidrug resistance was observed in 2.6% of OBS and 37.5% of the water isolates. Also, 1.2% of the ESBL-producing E. coli were isolated from OBS, whereas 50% of the E. coli isolated from water sources were ESBL producers possessing the CTX-M-15 gene. The most concerning aspect of our findings was the presence of human-associated E. coli sequence types in the water samples, for example, ST156-complex156, ST10-complex10 and ST46. Conclusion: This study reports the presence of multidrug-resistant ESBL-producing E. coli in OBSs and nearby aquatic sources in Bangladesh.

  3. Synergistic Antimicrobial Activity of Camellia sinensis and Juglans regia against Multidrug-Resistant Bacteria

    OpenAIRE

    Amber Farooqui; Adnan Khan; Ilaria Borghetto; Kazmi, Shahana U.; Salvatore Rubino; Bianca Paglietti

    2015-01-01

    Synergistic combinations of antimicrobial agents with different mechanisms of action have been introduced as more successful strategies to combat infections involving multidrug resistant (MDR) bacteria. In this study, we investigated synergistic antimicrobial activity of Camellia sinensis and Juglans regia which are commonly used plants with different antimicrobial agents. Antimicrobial susceptibility of 350 Gram-positive and Gram-negative strains belonging to 10 different bacterial species, ...

  4. Laboratory-based nationwide surveillance of antimicrobial resistance in Ghana

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    Opintan JA

    2015-11-01

    Full Text Available Japheth A Opintan,1 Mercy J Newman,1 Reuben E Arhin,1 Eric S Donkor,1 Martha Gyansa-Lutterodt,2 William Mills-Pappoe3 1Department of Medical Microbiology, School of Biomedical and Allied Health Sciences, University of Ghana, 2Pharmaceutical Services, Ministry of Health, Ghana Health Services, 3Clinical Laboratory Unit, Institutional Care Division, Ghana Health Service, Accra, Ghana Abstract: Global efforts are underway to combat antimicrobial resistance (AMR. A key target in this intervention is surveillance for local and national action. Data on AMR in Ghana are limited, and monitoring of AMR is nonexistent. We sought to generate baseline data on AMR, and to assess the readiness of Ghana in laboratory-based surveillance. Biomedical scientists in laboratories across Ghana with capacity to perform bacteriological culture were selected and trained. In-house standard operating protocols were used to perform microbiological investigations on clinical specimens. Additional microbiological tests and data analyses were performed at a centralized laboratory. Surveillance data were stored and analyzed using WHONET program files. A total of 24 laboratories participated in the training, and 1,598 data sets were included in the final analysis. A majority of the bacterial species were isolated from outpatients (963 isolates; 60.3%. Urine (617 isolates; 38.6% was the most common clinical specimen cultured, compared to blood (100 isolates; 6.3%. Ten of 18 laboratories performed blood culture. Bacteria isolated included Escherichia coli (27.5%, Pseudomonas spp. (14.0%, Staphylococcus aureus (11.5%, Streptococcus spp. (2.3%, and Salmonella enterica serovar Typhi (0.6%. Most of the isolates were multidrug-resistant, and over 80% of them were extended-spectrum beta-lactamases-producing. Minimum inhibitory concentration levels at 50% and at 90% for ciprofloxacin, ceftriaxone, and amikacin on selected multidrug-resistant bacteria species ranged between 2 µg/mL and

  5. Prevalence of Nontyphoidal Salmonella and Salmonella Strains with Conjugative Antimicrobial-Resistant Serovars Contaminating Animal Feed in Texas.

    Science.gov (United States)

    Hsieh, Yi-Cheng; Poole, Toni L; Runyon, Mick; Hume, Michael; Herrman, Timothy J

    2016-02-01

    The objective of this study was to characterize 365 nontyphoidal Salmonella enterica isolates from animal feed. Among the 365 isolates, 78 serovars were identified. Twenty-four isolates (7.0%) were recovered from three of six medicated feed types. Three of these isolates derived from the medicated feed, Salmonella Newport, Salmonella Typhimurium var. O 5- (Copenhagen), and Salmonella Lexington var. 15+ (Manila), displayed antimicrobial resistance. Susceptibility testing revealed that only 3.0% (12) of the 365 isolates displayed resistance to any of the antimicrobial agents. These 12 isolates were recovered from unmedicated dry beef feed (n = 3), medicated dry beef feed (n = 3), cabbage culls (n = 2), animal protein products (n = 2), dry dairy cattle feed (n = 1), and fish meal (n = 1). Only Salmonella Newport and Salmonella Typhimurium var. O 5- (Copenhagen) were multidrug resistant. Both isolates possessed the IncA/C replicon and the blaCMY-2 gene associated with cephalosporin resistance. Plasmid replicons were amplified from 4 of 12 resistant isolates. Plasmids (40 kb) were Salmonella Montevideo and Salmonella Kentucky. Conjugation experiments were done using 7 of the 12 resistant isolates as donors. Only Salmonella Montevideo, possessing a plasmid and amplifying IncN, produced transconjugants. Transconjugants displayed the same antimicrobial resistance profile as did the donor isolate. Three isolates that amplified replicons corresponding to IncA/C or IncHI2 did not produce transconjugants at 30 or 37°C. The results of this study suggest that the prevalence of antimicrobial-resistant Salmonella contaminating animal feed is low in Texas. However, Salmonella was more prevalent in feed by-products; fish meal had the highest prevalence (84%) followed by animal protein products (48%). Ten of the 35 feed types had no Salmonella contamination. Further investigation is needed to understand the possible role of specific feed types in the dissemination of antimicrobial

  6. Antimicrobial-resistant Listeria species from retail meat in metro Detroit.

    Science.gov (United States)

    da Rocha, Liziane S; Gunathilaka, Gayathri U; Zhang, Yifan

    2012-12-01

    A total of 138 Listeria isolates from retail meat, including 58 Listeria welshimeri, 44 Listeria monocytogenes, and 36 Listeria innocua isolates, were characterized by antimicrobial susceptibility tests against nine antimicrobials. In addition, the 44 L. monocytogenes isolates were analyzed by serotype identification using PCR and genotyping using pulsed-field gel electrophoresis. Resistance to one or two antimicrobials was observed in 32 Listeria isolates (23.2%). No multidrug resistance was identified. Tetracycline resistance was the most common resistance phenotype and was identified in 22 Listeria isolates. A low prevalence of resistance to ciprofloxacin, erythromycin, gentamicin, and vancomycin was also detected. L. innocua isolates demonstrated the highest overall prevalence of antimicrobial resistance, 36.1%, followed by 34.1% in L. monocytogenes isolates and 6.9% in L. welshimeri isolates. Serotypes 1/2a, 1/2b, and 4b were identified in 19, 23, and 1 L. monocytogenes isolate, respectively. One isolate was untypeable. Fifteen L. monocytogenes isolates were antimicrobial resistant (12 were serotype 1/2b, 2 were 1/2a, and 1 was untypeable). A diverse population of L. monocytogenes isolates was identified, as evidenced by multiple pulsed-field gel electrophoresis patterns in the 44 isolates. The data indicate that Listeria contamination is common in retail meat. Although antimicrobial resistance still occurs at a low prevalence, multiple Listeria species can serve as reservoirs of antimicrobial resistance. Various antimicrobial susceptibilities may exist in L. monocytogenes isolates of different serotypes.

  7. 'Disperse abroad in the land': the role of wildlife in the dissemination of antimicrobial resistance.

    Science.gov (United States)

    Arnold, Kathryn E; Williams, Nicola J; Bennett, Malcolm

    2016-08-01

    Antimicrobial resistance (AMR) has been detected in the microbiota of many wildlife species, including long-distance migrants. Inadequately treated wastes from humans and livestock dosed with antimicrobial drugs are often assumed to be the main sources of AMR to wildlife. While wildlife populations closely associated with human populations are more likely to harbour clinically important AMR related to that found in local humans and livestock, AMR is still common in remote wildlife populations with little direct human influence. Most reports of AMR in wildlife are survey based and/or small scale, so researchers can only speculate on possible sources and sinks of AMR or the impact of wildlife AMR on clinical resistance. This lack of quantitative data on the flow of AMR genes and AMR bacteria across the natural environment could reflect the numerous AMR sources and amplifiers in the populated world. Ecosystems with relatively simple and well-characterized potential inputs of AMR can provide tractable, but realistic, systems for studying AMR in the natural environment. New tools, such as animal tracking technologies and high-throughput sequencing of resistance genes and mobilomes, should be integrated with existing methodologies to understand how wildlife maintains and disperses AMR.

  8. 'Disperse abroad in the land': the role of wildlife in the dissemination of antimicrobial resistance.

    Science.gov (United States)

    Arnold, Kathryn E; Williams, Nicola J; Bennett, Malcolm

    2016-08-01

    Antimicrobial resistance (AMR) has been detected in the microbiota of many wildlife species, including long-distance migrants. Inadequately treated wastes from humans and livestock dosed with antimicrobial drugs are often assumed to be the main sources of AMR to wildlife. While wildlife populations closely associated with human populations are more likely to harbour clinically important AMR related to that found in local humans and livestock, AMR is still common in remote wildlife populations with little direct human influence. Most reports of AMR in wildlife are survey based and/or small scale, so researchers can only speculate on possible sources and sinks of AMR or the impact of wildlife AMR on clinical resistance. This lack of quantitative data on the flow of AMR genes and AMR bacteria across the natural environment could reflect the numerous AMR sources and amplifiers in the populated world. Ecosystems with relatively simple and well-characterized potential inputs of AMR can provide tractable, but realistic, systems for studying AMR in the natural environment. New tools, such as animal tracking technologies and high-throughput sequencing of resistance genes and mobilomes, should be integrated with existing methodologies to understand how wildlife maintains and disperses AMR. PMID:27531155

  9. Antimicrobial Resistance of Staphylococcal Strains Isolated from Various Pathological Products

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    Laura-Mihaela SIMON

    2010-12-01

    Full Text Available Background: The optimal choice of antimicrobial therapy is an important problem in hospital environment in which the selection of resistant and virulent strains easy occurs. S. aureus and especially MRSA(methicillin-resistant S. aureus creates difficulties in both treatment and prevention of nosocomial infections. Aim: The purpose of this study is to determine the sensitivity and the resistance to chemotherapy of staphylococci strains isolated from various pathological products. Material and Method: We identified Staphylococccus species after morphological appearance, culture properties, the production of coagulase, hemolisines and the enzyme activity. The susceptibility tests were performed on Mueller-Hinton medium according to CLSI (Clinical and Laboratory Standards Institute. Results: The strains were: MSSA (methicillin-susceptible S. aureus (74%, MRSA (8%, MLS B (macrolides, lincosamides and type B streptogramines resistance (12% and MRSA and MLS B (6%. MRSA strains were more frequently isolated from sputum. MRSA associated with the MLS B strains were more frequently isolated from pus. MLS B strains were more frequently isolated from sputum and throat secretions. All S. aureus strains were susceptible to vancomycin and teicoplanin. Conclusions: All staphylococcal infections require resistance testing before treatment. MLS B shows a high prevalence among strains of S. aureus. The association between MLS B and MRSA remains a major problem in Romania.

  10. Antimicrobial resistance determinants in Staphylococcus spp. recovered from birds of prey in Portugal.

    Science.gov (United States)

    Sousa, Margarida; Silva, Nuno; Igrejas, Gilberto; Silva, Filipe; Sargo, Roberto; Alegria, Nuno; Benito, Daniel; Gómez, Paula; Lozano, Carmen; Gómez-Sanz, Elena; Torres, Carmen; Caniça, Manuela; Poeta, Patrícia

    2014-07-16

    Antibiotic resistance among wild animals represent an emerging public health concern. The objective of this study was to analyze the staphylococcal nasal microbiota in birds of prey and their content in antimicrobial resistance determinants. Nasal samples from 16 birds of prey were collected, swabs were dipped and incubated into BHI broth [6.5% NaCl] and later seeded on manitol salt agar and oxacillin-resistance screening agar base media. Staphylococcal colonies were isolated from both media and were identified by biochemical and molecular methods. Susceptibility testing to 18 antimicrobial agents was performed by disk-diffusion method. Six of the 16 tested animals carried staphylococci (37.5%) and 7 isolates of the following species were recovered: Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Staphylococcus sciuri rodentium, Staphylococcus cohnii urealitycum, and Staphylococcus gallinarum. The S. aureus isolate was penicillin-resistant (with blaZ gene) but methicillin-susceptible and was ascribed to spa-type t012, sequence-type ST30 and agr-type III. The S. epidermidis isolate carried blaZ, mecA, mrs(A/B), mphC, tet(K), drfA, and fusC genes, ica operon, and was typed as ST35. The genes ant6'-Ia, tet(K), tet(L), dfrG, cat221, cat194, and cat223 were detected in S. saprophyticus or S. gallinarum isolates. Birds of prey seem to be a natural reservoir of S. aureus and coagulase-negative staphylococci resistant to multiple antibiotics. Due to the convergence between habitats, the contact between wildlife, other animals and humans is now more common and this involves an increased possibility of interchange of these microorganisms in the different ecosystems.

  11. Antimicrobial resistance determinants in Staphylococcus spp. recovered from birds of prey in Portugal.

    Science.gov (United States)

    Sousa, Margarida; Silva, Nuno; Igrejas, Gilberto; Silva, Filipe; Sargo, Roberto; Alegria, Nuno; Benito, Daniel; Gómez, Paula; Lozano, Carmen; Gómez-Sanz, Elena; Torres, Carmen; Caniça, Manuela; Poeta, Patrícia

    2014-07-16

    Antibiotic resistance among wild animals represent an emerging public health concern. The objective of this study was to analyze the staphylococcal nasal microbiota in birds of prey and their content in antimicrobial resistance determinants. Nasal samples from 16 birds of prey were collected, swabs were dipped and incubated into BHI broth [6.5% NaCl] and later seeded on manitol salt agar and oxacillin-resistance screening agar base media. Staphylococcal colonies were isolated from both media and were identified by biochemical and molecular methods. Susceptibility testing to 18 antimicrobial agents was performed by disk-diffusion method. Six of the 16 tested animals carried staphylococci (37.5%) and 7 isolates of the following species were recovered: Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Staphylococcus sciuri rodentium, Staphylococcus cohnii urealitycum, and Staphylococcus gallinarum. The S. aureus isolate was penicillin-resistant (with blaZ gene) but methicillin-susceptible and was ascribed to spa-type t012, sequence-type ST30 and agr-type III. The S. epidermidis isolate carried blaZ, mecA, mrs(A/B), mphC, tet(K), drfA, and fusC genes, ica operon, and was typed as ST35. The genes ant6'-Ia, tet(K), tet(L), dfrG, cat221, cat194, and cat223 were detected in S. saprophyticus or S. gallinarum isolates. Birds of prey seem to be a natural reservoir of S. aureus and coagulase-negative staphylococci resistant to multiple antibiotics. Due to the convergence between habitats, the contact between wildlife, other animals and humans is now more common and this involves an increased possibility of interchange of these microorganisms in the different ecosystems. PMID:24679961

  12. Characterization of the variable region in the class 1 integron of antimicrobial-resistant Escherichia coli isolated from surface water

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    Natália Canal

    2016-06-01

    Full Text Available Abstract Fecal bacteria are considered to be a potential reservoir of antimicrobial resistance genes in the aquatic environment and could horizontally transfer these genes to autochthonous bacteria when carried on transferable and/or mobile genetic elements. Such circulation of resistance genes constitutes a latent public health hazard. The aim of this study was to characterize the variable region of the class 1 integron and relate its genetic content to resistance patterns observed in antimicrobial-resistant Escherichia coli isolated from the surface waters of Patos Lagoon, Southern Brazil. Genetic diversity of the isolates and presence of the qacEΔ1 gene, which confers resistance to quaternary ammonium compounds, were also investigated. A total of 27 isolates were analyzed. The variable region harbored dfrA17, dfrA1 and dfrA12 genes, which confer resistance to trimethoprim, and aadA1, aadA5 and aadA22 genes that encode resistance to streptomycin/spectinomycin. Most of the isolates were considered resistant to quaternary ammonium compounds and all of them carried the qacE Δ1 gene at the 3′ conserved segment of the integron. ERIC-PCR analyses of E. coli isolates that presented the integrons showed great genetic diversity, indicating diverse sources of contamination in this environment. These results suggest that fecal bacteria with class 1 integrons in aquatic environments are potentially important reservoirs of antibiotic-resistance genes and may transfer these elements to other bacteria that are capable of infecting humans.

  13. The bigger picture: the history of antibiotics and antimicrobial resistance displayed by scientometric data.

    Science.gov (United States)

    Brandt, Christian; Makarewicz, Oliwia; Fischer, Thomas; Stein, Claudia; Pfeifer, Yvonne; Werner, Guido; Pletz, Mathias W

    2014-11-01

    Monitoring the rapid global spread of antimicrobial resistance requires an over-regional and fast surveillance tool. Data from major surveillance studies based on aggregated results of selected sentinel laboratories or retrospective strain collections are not available for the whole scientific community and are limited by time and region. Thus, we tested an alternative approach to monitor resistance trends by automated semantic and scientometric analysis of all (>100000) related PubMed entries. A semantic search was done using 'Gene Ontology' and MeSH vocabulary and additional search terms for further data refinement. Data extraction was performed using the semantic search engine 'GoPubMed'. The timely relationship between introduction of novel β-lactam antibiotic classes into the market and emergence of respective resistance was investigated using nearly 22300 publications over the last 70 years. Further analysis was done with around 54000 publications related to 'infectious diseases' and an additional 50000 publications related to 'antimicrobial resistance' to estimate current trends in publication interest regarding resistance development since 1940. Scientometric results were compared with data from the major surveillance network EARS-Net. Furthermore, the relationship between micro-organism, year and antibiotic market introduction was investigated for eight key antibiotics using nearly 37500 publications. Owing to influencing factors such as availability of alternative antibiotics, scientometric analysis correlated only partly with resistance development. However, it provides a fast, reliable and global overview of the clinical and public health importance of a specific resistance including the period of the 1940s-1980s, when resistance surveillance studies were not yet established.

  14. Antimicrobial resistance of Helicobacter pylori strains to five antibiotics, including levofloxacin, in Northwestern Turkey

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    Reyhan Caliskan

    2015-06-01

    Full Text Available INTRODUCTION: Antibiotic resistance is the main factor that affects the efficacy of current therapeutic regimens against Helicobacter pylori. This study aimed to determine the rates of resistance to efficacy clarithromycin, amoxicillin, tetracycline, levofloxacin and metronidazole among H. pylori strains isolated from Turkish patients with dyspepsia. METHODS: H. pylori was cultured from corpus and antrum biopsies that were collected from patients with dyspeptic symptoms, and the antimicrobial susceptibility of H. pylori was determined using the E-test (clarithromycin, amoxicillin, tetracycline, metronidazole and levofloxacin according to the EUCAST breakpoints. Point mutations in the 23S rRNA gene of clarithromycin-resistant strains were investigated using real-time PCR. RESULTS: A total of 98 H. pylori strains were isolated, all of which were susceptible to amoxicillin and tetracycline. Of these strains, 36.7% (36/98 were resistant to clarithromycin, 35.5% (34/98 were resistant to metronidazole, and 29.5% (29/98 were resistant to levofloxacin. Multiple resistance was detected in 19.3% of the isolates. The A2143G and A2144G point mutations in the 23S rRNA-encoding gene were found in all 36 (100% of the clarithromycin-resistant strains. Additionally, the levofloxacin MIC values increased to 32 mg/L in our H. pylori strains. Finally, among the clarithromycin-resistant strains, 27.2% were resistant to levofloxacin, and 45.4% were resistant to metronidazole. CONCLUSIONS: We conclude that treatment failure after clarithromycin- or levofloxacin-based triple therapy is not surprising and that metronidazole is not a reliable agent for the eradication of H. pylori infection in Turkey.

  15. Isolation and Characterization of Antimicrobial-Resistant Nontyphoidal Salmonella enterica Serovars from Imported Food Products.

    Science.gov (United States)

    Bae, Dongryeoul; Kweon, Ohgew; Khan, Ashraf A

    2016-08-01

    The objective of this study was to determine antimicrobial resistance and elucidate the resistance mechanism in nontyphoidal Salmonella enterica serovars isolated from food products imported into the United States from 2011 to 2013. Food products contaminated with antimicrobial-resistant nontyphoidal S. enterica were mainly imported from Taiwan, Indonesia, Vietnam, and China. PCR, DNA sequencing, and plasmid analyses were used to characterize antimicrobial resistance determinants. Twentythree of 110 S. enterica isolates were resistant to various antimicrobial classes, including β-lactam, aminoglycoside, phenicol, glycopeptide, sulfonamide, trimethoprim, and/or fluoroquinolone antimicrobial agents. Twelve of the isolates were multidrug resistant strains. Antimicrobial resistance determinants blaTEM-1, blaCTX-M-9, blaOXA-1, tetA, tetB, tetD, dfrA1, dfrV, dhfrI, dhfrXII, drf17, aadA1, aadA2, aadA5, orfC, qnrS, and mutations of gyrA and parC were detected in one or more antimicrobial-resistant nontyphoidal S. enterica strains. Plasmid profiles revealed that 12 of the 23 antimicrobial-resistant strains harbored plasmids with incompatibility groups IncFIB, IncHI1, IncI1, IncN, IncW, and IncX. Epidemiologic and antimicrobial resistance monitoring data combined with molecular characterization of antimicrobial resistance determinants in Salmonella strains isolated from imported food products may provide information that can be used to establish or implement food safety programs to improve public health.

  16. Isolation and Characterization of Antimicrobial-Resistant Nontyphoidal Salmonella enterica Serovars from Imported Food Products.

    Science.gov (United States)

    Bae, Dongryeoul; Kweon, Ohgew; Khan, Ashraf A

    2016-08-01

    The objective of this study was to determine antimicrobial resistance and elucidate the resistance mechanism in nontyphoidal Salmonella enterica serovars isolated from food products imported into the United States from 2011 to 2013. Food products contaminated with antimicrobial-resistant nontyphoidal S. enterica were mainly imported from Taiwan, Indonesia, Vietnam, and China. PCR, DNA sequencing, and plasmid analyses were used to characterize antimicrobial resistance determinants. Twentythree of 110 S. enterica isolates were resistant to various antimicrobial classes, including β-lactam, aminoglycoside, phenicol, glycopeptide, sulfonamide, trimethoprim, and/or fluoroquinolone antimicrobial agents. Twelve of the isolates were multidrug resistant strains. Antimicrobial resistance determinants blaTEM-1, blaCTX-M-9, blaOXA-1, tetA, tetB, tetD, dfrA1, dfrV, dhfrI, dhfrXII, drf17, aadA1, aadA2, aadA5, orfC, qnrS, and mutations of gyrA and parC were detected in one or more antimicrobial-resistant nontyphoidal S. enterica strains. Plasmid profiles revealed that 12 of the 23 antimicrobial-resistant strains harbored plasmids with incompatibility groups IncFIB, IncHI1, IncI1, IncN, IncW, and IncX. Epidemiologic and antimicrobial resistance monitoring data combined with molecular characterization of antimicrobial resistance determinants in Salmonella strains isolated from imported food products may provide information that can be used to establish or implement food safety programs to improve public health. PMID:27497122

  17. Microarray Evaluation of Antimicrobial Resistance and Virulence of Escherichia coli Isolates from Portuguese Poultry

    OpenAIRE

    Nuno Mendonça; Rui Figueiredo; Catarina Mendes; Card, Roderick M.; Anjum, Muna F.; Gabriela Jorge da Silva

    2016-01-01

    The presence of antimicrobial resistance and virulence factors of 174 Escherichia coli strains isolated from healthy Portuguese Gallus gallus was evaluated. Resistance profiles were determined against 33 antimicrobials by microbroth dilution. Resistance was prevalent for tetracycline (70%) and ampicillin (63%). Extended-spectrum beta-lactamase (ESBL) phenotype was observed in 18% of the isolates. Multidrug resistance was found in 56% of isolates. A subset of 74 isolates were screened by DNA m...

  18. Prevalence, antimicrobial resistance, and molecular characterization of methicillin-resistant Staphylococcus aureus from bulk tank milk of dairy herds.

    Science.gov (United States)

    Kreausukon, K; Fetsch, A; Kraushaar, B; Alt, K; Müller, K; Krömker, V; Zessin, K-H; Käsbohrer, A; Tenhagen, B-A

    2012-08-01

    It was the objective of the study to estimate the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in bulk tank milk from German dairy herds and to characterize isolates from bulk tank milk with respect to their Staph. aureus protein A (spa) and staphylococcal cassette chromosome mec (SCCmec) type, their phenotypic antimicrobial resistance and resistance- resp. virulence-associated genes using broth microdilution and a microarray for Staph. aureus. Bulk tank milk samples (25 mL) were tested for MRSA using a 2-step selective enrichment protocol. Presumptive MRSA were confirmed by PCR. Thirty-six isolates collected from bulk tank milk of dairy herds in 2009 and 2010 were included in the characterization. All isolates displayed spa-types assigned to the clonal complex CC398. Based on the epidemiological cut-off values for the interpretation of minimum inhibitory concentrations isolates were resistant to tetracycline (100%), clindamycin (58%), erythromycin (52%), quinupristin/dalfopristin (36%), and kanamycin (27%). Isolates did not carry genes associated with typical virulence factors for Staph. aureus such as the Panton-Valentine leukocidin. However, they did carry hemolysin genes. Livestock-associated MRSA of CC398 does occur in German dairy herds and the strains have similar properties as described for strains from pigs. PMID:22818451

  19. Resistance to antimicrobial peptides in Gram-negative bacteria.

    Science.gov (United States)

    Gruenheid, Samantha; Le Moual, Hervé

    2012-05-01

    Antimicrobial peptides (AMPs) are present in virtually all organisms and are an ancient and critical component of innate immunity. In mammals, AMPs are present in phagocytic cells, on body surfaces such as skin and mucosa, and in secretions and body fluids such as sweat, saliva, urine, and breast milk, consistent with their role as part of the first line of defense against a wide range of pathogenic microorganisms including bacteria, viruses, and fungi. AMPs are microbicidal and have also been shown to act as immunomodulators with chemoattractant and signaling activities. During the co-evolution of hosts and bacterial pathogens, bacteria have developed the ability to sense and initiate an adaptive response to AMPs to resist their bactericidal activity. Here, we review the various mechanisms used by Gram-negative bacteria to sense and resist AMP-mediated killing. These mechanisms play an important role in bacterial resistance to host-derived AMPs that are encountered during the course of infection. Bacterial resistance to AMPs should also be taken into consideration in the development and use of AMPs as anti-infective agents, for which there is currently a great deal of academic and commercial interest.

  20. The Role of Antimicrobial Peptides in Preventing Multidrug-Resistant Bacterial Infections and Biofilm Formation

    Directory of Open Access Journals (Sweden)

    Kyung-Soo Hahm

    2011-09-01

    Full Text Available Over the last decade, decreasing effectiveness of conventional antimicrobial-drugs has caused serious problems due to the rapid emergence of multidrug-resistant pathogens. Furthermore, biofilms, which are microbial communities that cause serious chronic infections and dental plaque, form environments that enhance antimicrobial resistance. As a result, there is a continuous search to overcome or control such problems, which has resulted in antimicrobial peptides being considered as an alternative to conventional drugs. Antimicrobial peptides are ancient host defense effector molecules in living organisms. These peptides have been identified in diverse organisms and synthetically developed by using peptidomimic techniques. This review was conducted to demonstrate the mode of action by which antimicrobial peptides combat multidrug-resistant bacteria and prevent biofilm formation and to introduce clinical uses of these compounds for chronic disease, medical devices, and oral health. In addition, combinations of antimicrobial peptides and conventional drugs were considered due to their synergetic effects and low cost for therapeutic treatment.

  1. Eight-year Surveillance of Antimicrobial Resistance among Enterococcus Spp. Isolated in the First Bethune Hospital

    Science.gov (United States)

    Xu, Jiancheng; Wang, Liqiang; Wang, Kai; Zhou, Qi

    This study was to investigate the antimicrobial resistance of Enterococcus spp. isolated in 8 consecutive years in the First Bethune Hospital. Disk diffusion test was used to study the antimicrobial resistance. The data were analyzed by WHONET 5 software according to Clinical and Laboratory Standards Institute (CLSI). Most of 1446 strains of Enterococcus spp. were collected from urine 640 (44.3%), sputum 315 (21.8%), secretions and pus 265 (18.3%) during the past 8 years. The rates of high-level aminoglycoside resistance in Enterococcus faecalis and Enterococcus faecium were 57.4%∼75.9% and 69.0%∼93.8% during the past 8 years, respectively. No Enterococcus spp. was resistant to vancomycin. The antimicrobial resistance of Enterococcus spp. had increased in recent 8 years. The change of the antimicrobial resistance should be investigated in order to direct rational drug usage in the clinic and prevent bacterial strain of drug resistance from being transmitted.

  2. Analysis of the Antimicrobial-Resistant Gene and Virulence Gene Carried by Staphylococcus Aureus Collected from Bloodstream Infections in Tianjin:2006-2011%2006-2011年60株血感染金黄色葡萄球菌毒素及耐药基因分析

    Institute of Scientific and Technical Information of China (English)

    王立新; 胡神明; 胡志东; 田彬; 李静; 王凤霞; 杨华

    2013-01-01

    Objective To investigate resistance profile, antimicrobial-resistant genes and virulence genes carried by 60 staphylococcus aureus collected from bloodstream infections in General Hospital of Tianjin Medical University from 2006 to 2011.Methods The bacteria identification and the antimicrobial susceptibility test were conducted by VITEK-2 compact automatic system.Methicillin resistant staphylococcus aureus (MRSA) were screened by disk diffusion method with cefoxitin.The polymerase chain reaction (PCR)was used to detect genes of mecA, qacA, pvl, sea, seb, secI, sed, see and TSST-1.Results The resistance rates of 60 isolates to penicillin, erythromycin, clindamycin and gentamicin were 91.7%, 65.0%, 65.0% and 40.0%, respectively.All of the isolates were susceptible to vancomycin, linezolid, and tigecycline.Among the 60 isolates, the positive rates of mecA and qacA werel3 (21.7%) and 3(5.0%) respectively.The positive rates of pvl, sea, seb,sec and sed were 4 (6.7%),20(33.3%), 3 (5%),9 (15.0%) and 7 (11.7%).Both see and tst were negative in all strains.Conclusion The resistance rates of staphylococcus aureus collected from bloodstream infections were high to penicillin , erythromycin, clindamycin and gentamicin.The various toxin and the antimicrobial-resistant genes were positive in staphylococcus aureus.We should pay attention to the detection of the antimicrobial-resistant gene and virulence gene.%目的 了解2006-2011年临床分离的60株血感染金黄色葡萄球菌的耐药情况及毒素基因和耐药基因的流行情况.方法 VITEK 2-compact全自动细菌鉴定仪及配套鉴定卡、药敏卡对细菌进行鉴定及药敏试验;头孢西丁纸片扩散法筛选耐甲氧西林金黄色葡萄球菌(MRSA);应用聚合酶链反应(PCR)检测mecA、耐消毒剂基因(qacA)、杀白细胞素基因(pvl)、肠毒素基因(sea、seb、secl、sed、see)及中毒休克综合征毒素-1基因(tst).结果 60株金黄色葡萄球菌

  3. Antimicrobial hydrogels: a new weapon in the arsenal against multidrug-resistant infections.

    Science.gov (United States)

    Ng, Victor W L; Chan, Julian M W; Sardon, Haritz; Ono, Robert J; García, Jeannette M; Yang, Yi Yan; Hedrick, James L

    2014-11-30

    The rapid emergence of antibiotic resistance in pathogenic microbes is becoming an imminent global public health problem. Treatment with conventional antibiotics often leads to resistance development as the majority of these antibiotics act on intracellular targets, leaving the bacterial morphology intact. Thus, they are highly prone to develop resistance through mutation. Much effort has been made to develop macromolecular antimicrobial agents that are less susceptible to resistance as they function by microbial membrane disruption. Antimicrobial hydrogels constitute an important class of macromolecular antimicrobial agents, which have been shown to be effective in preventing and treating multidrug-resistant infections. Advances in synthetic chemistry have made it possible to tailor molecular structure and functionality to impart broad-spectrum antimicrobial activity as well as predictable mechanical and rheological properties. This has significantly broadened the scope of potential applications that range from medical device and implant coating, sterilization, wound dressing, to antimicrobial creams for the prevention and treatment of multidrug-resistant infections. In this review, advances in both chemically and physically cross-linked natural and synthetic hydrogels possessing intrinsic antimicrobial properties or loaded with antibiotics, antimicrobial polymers/peptides and metal nanoparticles are highlighted. Relationships between physicochemical properties and antimicrobial activity/selectivity, and possible antimicrobial mechanisms of the hydrogels are discussed. Approaches to mitigating toxicity of metal nanoparticles that are encapsulated in hydrogels are reviewed. In addition, challenges and future perspectives in the development of safe and effective antimicrobial hydrogel systems especially involving co-delivery of antimicrobial polymers/peptides and conventional antimicrobial agents for eventual clinical applications are presented.

  4. Antimicrobial hydrogels: a new weapon in the arsenal against multidrug-resistant infections.

    Science.gov (United States)

    Ng, Victor W L; Chan, Julian M W; Sardon, Haritz; Ono, Robert J; García, Jeannette M; Yang, Yi Yan; Hedrick, James L

    2014-11-30

    The rapid emergence of antibiotic resistance in pathogenic microbes is becoming an imminent global public health problem. Treatment with conventional antibiotics often leads to resistance development as the majority of these antibiotics act on intracellular targets, leaving the bacterial morphology intact. Thus, they are highly prone to develop resistance through mutation. Much effort has been made to develop macromolecular antimicrobial agents that are less susceptible to resistance as they function by microbial membrane disruption. Antimicrobial hydrogels constitute an important class of macromolecular antimicrobial agents, which have been shown to be effective in preventing and treating multidrug-resistant infections. Advances in synthetic chemistry have made it possible to tailor molecular structure and functionality to impart broad-spectrum antimicrobial activity as well as predictable mechanical and rheological properties. This has significantly broadened the scope of potential applications that range from medical device and implant coating, sterilization, wound dressing, to antimicrobial creams for the prevention and treatment of multidrug-resistant infections. In this review, advances in both chemically and physically cross-linked natural and synthetic hydrogels possessing intrinsic antimicrobial properties or loaded with antibiotics, antimicrobial polymers/peptides and metal nanoparticles are highlighted. Relationships between physicochemical properties and antimicrobial activity/selectivity, and possible antimicrobial mechanisms of the hydrogels are discussed. Approaches to mitigating toxicity of metal nanoparticles that are encapsulated in hydrogels are reviewed. In addition, challenges and future perspectives in the development of safe and effective antimicrobial hydrogel systems especially involving co-delivery of antimicrobial polymers/peptides and conventional antimicrobial agents for eventual clinical applications are presented. PMID:25450263

  5. Antimicrobial resistance and biological governance: explanations for policy failure.

    Science.gov (United States)

    Wallinga, D; Rayner, G; Lang, T

    2015-10-01

    The paper reviews the state of policy on antimicrobial use and the growth of antimicrobial resistance (AMR). AMR was anticipated at the time of the first use of antibiotics by their originators. For decades, reports and scientific papers have expressed concern about AMR at global and national policy levels, yet the problem, first exposed a half-century ago, worsened. The paper considers the explanations for this policy failure and the state of arguments about ways forward. These include: a deficit of economic incentivisation; complex interventions in behavioural dynamics; joint and separate shifts in medical and animal health regimes; consumerism; belief in technology; and a narrative that in a 'war on bugs' nature can be beaten by human ingenuity. The paper suggests that these narratives underplay the biological realities of the human-animal-biosphere being in constant flux, an understanding which requires an ecological public health analysis of AMR policy development and failure. The paper suggests that effective policy change requires simultaneous actions across policy levels. No single solution is possible, since AMR is the result of long-term human intervention which has accelerated certain trends in the evolution of a microbial ecosystem shared by humans, animals and other biological organisms inhabiting that ecosystem. Viewing the AMR crisis today through an ecological public health lens has the advantage of reuniting the social-ecological and bio-ecological perspectives which have been separated within public health. PMID:26454427

  6. Control of Neisseria gonorrhoeae in the era of evolving antimicrobial resistance.

    Science.gov (United States)

    Barbee, Lindley A; Dombrowski, Julia C

    2013-12-01

    Neisseria gonorrhoeae has developed resistance to all previous first-line antimicrobial therapies over the past 75 years. Today the cephalosporins, the last available antibiotic class that is sufficiently effective, are also threatened by evolving resistance. Screening for asymptomatic gonorrhea in women and men who have sex with men, treating with a dual antibiotic regimen, ensuring effective partner therapy, and remaining vigilant for treatment failures constitute critical activities for clinicians in responding to evolving antimicrobial resistance. This article reviews the epidemiology, history of antimicrobial resistance, current screening and treatment guidelines, and future treatment options for gonorrhea.

  7. Antimicrobial Resistance and Molecular Characteristics of Nasal Staphylococcus aureus Isolates From Newly Admitted Inpatients.

    Science.gov (United States)

    Chen, Xu; Sun, Kangde; Dong, Danfeng; Luo, Qingqiong; Peng, Yibing; Chen, Fuxiang

    2016-05-01

    Staphylococcus aureus, or methicillin-resistant S. aureus (MRSA), is a significant pathogen in both nosocomial and community infections. Community-associated MRSA (CA-MRSA) strains tend to be multi-drug resistant and to invade hospital settings. This study aimed to assess the antimicrobial resistance and molecular characteristicsof nasal S. aureus among newlyadmitted inpatients.In the present study, 66 S. aureus isolates, including 10 healthcare-associated MRSA (HA-MRSA), 8 CA-MRSA, and 48 methicillin-sensitive S. aureus (MSSA) strains, were found in the nasal cavities of 62 patients by screening 292 newlyadmitted patients. Antimicrobial resistance and molecular characteristics of these isolates, including spa-type, sequence type (ST) and SCCmec type, were investigated. All isolates were sensitive to linezolid, teicoplanin, and quinupristin/dalfopristin, but high levels of resistance to penicillin and erythromycin were detected. According to D-test and erm gene detection results, the cMLS(B) and iMLS(B) phenotypes were detected in 24 and 16 isolates, respectively. All 10 HA-MRSA strains displayed the cMLS(B) phenotypemediated by ermA or ermA/ermC, while the cMLS(B) CA-MRSA and MSSA strains carried the ermB gene. Molecular characterization revealedall 10 HA-MRSA strains were derived from the ST239-SCCmec III clone, and four out of eight CA-MRSA strains were t437-ST59-SCCmec V. The results suggest that patients play an indispensable role in transmitting epidemic CA-MRSA and HA-MRSA strains. PMID:26915614

  8. Impact of medicated feed along with clay mineral supplementation on Escherichia coli resistance to antimicrobial agents in pigs after weaning in field conditions.

    Science.gov (United States)

    Jahanbakhsh, Seyedehameneh; Kabore, Kiswendsida Paul; Fravalo, Philippe; Letellier, Ann; Fairbrother, John Morris

    2015-10-01

    The aim of this study was to examine changes in antimicrobial resistance (AMR) phenotype and virulence and AMR gene profiles in Escherichia coli from pigs receiving in-feed antimicrobial medication following weaning and the effect of feed supplementation with a clay mineral, clinoptilolite, on this dynamic. Eighty E. coli strains isolated from fecal samples of pigs receiving a diet containing chlortetracycline and penicillin, with or without 2% clinoptilolite, were examined for antimicrobial resistance to 15 antimicrobial agents. Overall, an increased resistance to 10 antimicrobials was observed with time. Supplementation with clinoptilolite was associated with an early increase but later decrease in blaCMY-2, in isolates, as shown by DNA probe. Concurrently, a later increase in the frequency of blaCMY-2 and the virulence genes iucD and tsh was observed in the control pig isolates, being significantly greater than in the supplemented pigs at day 28. Our results suggest that, in the long term, supplementation with clinoptilolite could decrease the prevalence of E. coli carrying certain antimicrobial resistance and virulence genes.

  9. AMINOGLYCOSIDE RESISTANCE GENES IN Pseudomonas aeruginosa ISOLATES FROM CUMANA, VENEZUELA

    Directory of Open Access Journals (Sweden)

    Bertinellys TEIXEIRA

    2016-01-01

    Full Text Available The enzymatic modification of aminoglycosides by aminoglycoside-acetyltransferases (AAC, aminoglycoside-adenyltransferases (AAD, and aminoglycoside-phosphotransferases (APH, is the most common resistance mechanism in P. aeruginosa and these enzymes can be coded on mobile genetic elements that contribute to their dispersion. One hundred and thirty seven P. aeruginosa isolates from the University Hospital, Cumana, Venezuela (HUAPA were evaluated. Antimicrobial susceptibility was determined by the disk diffusion method and theaac, aadB and aph genes were detected by PCR. Most of the P. aeruginosa isolates (33/137 were identified from the Intensive Care Unit (ICU, mainly from discharges (96/137. The frequency of resistant P. aeruginosaisolates was found to be higher for the aminoglycosides tobramycin and amikacin (30.7 and 29.9%, respectively. Phenotype VI, resistant to these antibiotics, was the most frequent (14/49, followed by phenotype I, resistant to all the aminoglycosides tested (12/49. The aac(6´-Ib,aphA1 and aadB genes were the most frequently detected, and the simultaneous presence of several resistance genes in the same isolate was demonstrated. Aminoglycoside resistance in isolates ofP. aeruginosa at the HUAPA is partly due to the presence of the aac(6´-Ib, aphA1 andaadB genes, but the high rates of antimicrobial resistance suggest the existence of several mechanisms acting together. This is the first report of aminoglycoside resistance genes in Venezuela and one of the few in Latin America.

  10. Potential impact of antimicrobial resistance in wildlife, environment and human health

    OpenAIRE

    Hajer eRadhouani; Nuno eSilva; Patrícia ePoeta; Carmen eTorres; Susana eCorreia; Gilberto eIgrejas

    2014-01-01

    Given the significant spatial and temporal heterogeneity in antimicrobial resistance distribution and the factors that affect its evolution, dissemination, and persistence, it is important to highlight that antimicrobial resistance must be viewed as an ecological problem. Monitoring the resistance prevalence of indicator bacteria such as Escherichia coli and enterococci in wild animals makes it possible to show that wildlife has the potential to serve as an environmental reservoir and melting...

  11. Antimicrobial-Resistant Escherichia coli in Public Beach Waters in Quebec

    Directory of Open Access Journals (Sweden)

    Patricia Turgeon

    2012-01-01

    Full Text Available INTRODUCTION: Human exposure to antimicrobial-resistant bacteria may result in the transfer of resistance to commensal or pathogenic microbes present in the gastrointestinal tract, which may lead to severe health consequences and difficulties in treatment of future bacterial infections. It was hypothesized that the recreational waters from beaches represent a source of antimicrobial-resistant Escherichia coli for people engaging in water activities.

  12. Changing trends in antimicrobial-resistant pneumococci: it's not all bad news.

    Science.gov (United States)

    Low, Donald E

    2005-08-15

    In the early 1990s, we witnessed a dramatic and relentless increase in multidrug-resistant pneumococci worldwide. However, there is now evidence of decreasing resistance to some antimicrobials in some regions of the world. This may well be a result of several initiatives to promote the judicious use of antimicrobials, as well as the introduction of the pneumococcal conjugate vaccine, suggesting that the fight against resistance is maybe not futile.

  13. Development of bacterial resistance to biocides and antimicrobial agents as a consequence of biocide usage

    DEFF Research Database (Denmark)

    Seier-Petersen, Maria Amalie

    Biocides are chemical compounds with antimicrobial properties and they are widely used for disinfection, antiseptic and preservation purposes. Biocides have been applied for centuries due to early empirical approaches, such as cleansing of wounds with wine, vinegar and honey and salting of fish...... determined (Manuscript III). The biocides comprised benzalkonium chloride (BC), hydrogen peroxide (HP), sodium hypochlorite (SH), formaldehyde (FH), and caustic soda (NaOH). S. aureus isolates did in general not show reduced susceptibility to the biocides tested. However, a quaternary ammonium compound (QAC...... be of potential risk for human health, since these disinfectants are widely used at hospitals and in the food industry. Mobile genetic elements such as conjugative transposons are important vectors in the dissemination of antibiotic resistance determinants. Tn916 including the tetracycline resistance gene tet...

  14. Antimicrobial resistance in Neisseria gonorrhoeae in the 21st century: past, evolution, and future.

    Science.gov (United States)

    Unemo, Magnus; Shafer, William M

    2014-07-01

    Neisseria gonorrhoeae is evolving into a superbug with resistance to previously and currently recommended antimicrobials for treatment of gonorrhea, which is a major public health concern globally. Given the global nature of gonorrhea, the high rate of usage of antimicrobials, suboptimal control and monitoring of antimicrobial resistance (AMR) and treatment failures, slow update of treatment guidelines in most geographical settings, and the extraordinary capacity of the gonococci to develop and retain AMR, it is likely that the global problem of gonococcal AMR will worsen in the foreseeable future and that the severe complications of gonorrhea will emerge as a silent epidemic. By understanding the evolution, emergence, and spread of AMR in N. gonorrhoeae, including its molecular and phenotypic mechanisms, resistance to antimicrobials used clinically can be anticipated, future methods for genetic testing for AMR might permit region-specific and tailor-made antimicrobial therapy, and the design of novel antimicrobials to circumvent the resistance problems can be undertaken more rationally. This review focuses on the history and evolution of gonorrhea treatment regimens and emerging resistance to them, on genetic and phenotypic determinants of gonococcal resistance to previously and currently recommended antimicrobials, including biological costs or benefits; and on crucial actions and future advances necessary to detect and treat resistant gonococcal strains and, ultimately, retain gonorrhea as a treatable infection. PMID:24982323

  15. Antimicrobial resistance in Neisseria gonorrhoeae in the 21st century: past, evolution, and future.

    Science.gov (United States)

    Unemo, Magnus; Shafer, William M

    2014-07-01

    Neisseria gonorrhoeae is evolving into a superbug with resistance to previously and currently recommended antimicrobials for treatment of gonorrhea, which is a major public health concern globally. Given the global nature of gonorrhea, the high rate of usage of antimicrobials, suboptimal control and monitoring of antimicrobial resistance (AMR) and treatment failures, slow update of treatment guidelines in most geographical settings, and the extraordinary capacity of the gonococci to develop and retain AMR, it is likely that the global problem of gonococcal AMR will worsen in the foreseeable future and that the severe complications of gonorrhea will emerge as a silent epidemic. By understanding the evolution, emergence, and spread of AMR in N. gonorrhoeae, including its molecular and phenotypic mechanisms, resistance to antimicrobials used clinically can be anticipated, future methods for genetic testing for AMR might permit region-specific and tailor-made antimicrobial therapy, and the design of novel antimicrobials to circumvent the resistance problems can be undertaken more rationally. This review focuses on the history and evolution of gonorrhea treatment regimens and emerging resistance to them, on genetic and phenotypic determinants of gonococcal resistance to previously and currently recommended antimicrobials, including biological costs or benefits; and on crucial actions and future advances necessary to detect and treat resistant gonococcal strains and, ultimately, retain gonorrhea as a treatable infection.

  16. Antibiotic resistance and resistance genes in Escherichia coli from poultry farms, southwest Nigeria

    DEFF Research Database (Denmark)

    Adelowo, Olawale O.; Fagade, Obasola E.; Agersø, Yvonne

    2014-01-01

    Introduction: This study investigated the mechanisms of resistance in 36 E. coli isolated from waste, litter, soil and water samples collected from poultry farms in Southwestern Nigeria. Methodology: Minimum inhibitory concentration (MIC) distributions of the isolates were determined using...... the methods of the Clinical and Laboratory Standard Institute and resistance genes detected by PCR. Results: A total of 30 isolates (94%) showed resistance to more than one antimicrobial. Percentage resistance was: tetracycline 81%, sulphamethoxazole 67%, streptomycin 56%, trimethoprim 47 %, ciprofloxacin 42......%, ampicillin 36%, spectinomycin 28%, nalidixic acid 25%, chloramphenicol 22%, neomycin 14%, gentamicin 8%, amoxicillin-clavulanate, ceftiofur, cefotaxime, colistin, florfenicol and apramycin 0%. Resistance genes found among the isolates include bla-TEM (85%), sul2 (67%), sul3 (17%), aadA (65%), strA (70%), str...

  17. Occurrence of antimicrobial resistance in bacteria from diagnostic samples from dogs

    DEFF Research Database (Denmark)

    Pedersen, Karl; Pedersen, Kristina; Jensen, Helene;

    2007-01-01

    Objectives: To study the occurrence of antimicrobial resistance among common bacterial pathogens from dogs and relate resistance patterns to data on consumption of antimicrobials. Methods: The antimicrobial susceptibility patterns of 201 Staphylococcus intermedius, 37 Streptococcus canis, 39...... Pseudomonas aeruginosa, 25 Pasteurella multocida, 29 Proteus spp. and 449 Escherichia coli isolates from clinical submissions from dogs were determined by a broth-dilution method for determination of minimal inhibitory concentration. Data for consumption of antimicrobials were retrieved from Vet......Stat, a national database for reporting antimicrobial prescriptions. Results: The majority of the antimicrobials prescribed for dogs were broad-spectrum compounds, and extended-spectrum penicillins, cephalosporins and sulphonamides 1 trimethoprim together accounted for 81% of the total amount used for companion...

  18. Antimicrobial resistance in methicillin susceptible and methicillin resistant Staphylococcus pseudintermedius of canine origin

    DEFF Research Database (Denmark)

    Moodley, Arshnee; Damborg, Peter Panduro; Nielsen, Søren Saxmose

    2014-01-01

    from dogs in 27 countries between 1980 and 2013. Resistance to the most common antimicrobials tested for in published studies and important for the treatment of staphylococcal infections in dogs were assessed separately for methicillin resistant (MRSP) and methicillin susceptible (MSSP) isolates...... are collected and presented in a more harmonized way to allow more precise comparison of susceptibility patterns between studies. One way to accomplish this would be through systematic surveillance either at the country-level or at a larger scale across countries e.g. EU level....

  19. Prevalence and risk factors for carriage of antimicrobial-resistant Escherichia coli on household and small-scale chicken farms in the Mekong Delta of Vietnam

    NARCIS (Netherlands)

    V.T. Nguyen; J.J. Carrique-Mas; T.H Ngo; H.M. Ho; T.T. Ha; J.I. Campbell; T.N. Nguyen; N.N. Hoang; V.M. Pham; J.A. Wagenaar; A. Hardon; Q.H. Thai; C. Schultsz

    2015-01-01

    Objectives: To describe the prevalence of antimicrobial resistance among commensal Escherichia coli isolates on household and small-scale chicken farms, common in southern Vietnam, and to investigate the association of antimicrobial resistance with farming practices and antimicrobial usage. Methods:

  20. Prevalence and risk factors for carriage of antimicrobial-resistant Escherichia coli on household and small-scale chicken farms in the Mekong Delta of Vietnam

    NARCIS (Netherlands)

    Trung, Nguyen Vinh; Carrique-Mas, Juan J; Thi Hoa, Ngo; Mai, Ho Huynh; Tuyen, Ha Thanh; Campbell, James I; Nhung, Nguyen Thi; Nhung, Hoang Ngoc; Van Minh, Pham; Wagenaar, Jaap A; Hardon, Anita; Hieu, Thai Quoc; Schultsz, Constance

    2015-01-01

    OBJECTIVES: To describe the prevalence of antimicrobial resistance among commensal Escherichia coli isolates on household and small-scale chicken farms, common in southern Vietnam, and to investigate the association of antimicrobial resistance with farming practices and antimicrobial usage. METHODS:

  1. An assessment of antimicrobial resistant disease threats in Canada.

    Directory of Open Access Journals (Sweden)

    Michael J Garner

    Full Text Available Antimicrobial resistance (AMR of infectious agents is a growing concern for public health organizations. Given the complexity of this issue and how widespread the problem has become, resources are often insufficient to address all concerns, thus prioritization of AMR pathogens is essential for the optimal allocation of risk management attention. Since the epidemiology of AMR pathogens differs between countries, country-specific assessments are important for the determination of national priorities.To develop a systematic and transparent approach to AMR risk prioritization in Canada.Relevant AMR pathogens in Canada were selected through a transparent multi-step consensus process (n=32. Each pathogen was assessed using ten criteria: incidence, mortality, case-fatality, communicability, treatability, clinical impact, public/political attention, ten-year projection of incidence, economic impact, and preventability. For each pathogen, each criterion was assigned a numerical score of 0, 1, or 2, and multiplied by criteria-specific weighting determined through researcher consensus of importance. The scores for each AMR pathogen were summed and ranked by total score, where a higher score indicated greater importance. A sensitivity analysis was conducted to determine the effects of changing the criteria-specific weights.The AMR pathogen with the highest total weighted score was extended spectrum B-lactamase-producing (ESBL Enterobacteriaceae (score=77. When grouped by percentile, ESBL Enterobacteriaceae, Clostridium difficile, carbapenem-resistant Enterobacteriaceae, and methicillin-resistant Staphylococcus aureus were in the 80-100th percentile.This assessment provides useful information for prioritising public health strategies regarding AMR resistance at the national level in Canada. As the AMR environment and challenges change over time and space, this systematic and transparent approach can be adapted for use by other stakeholders domestically and

  2. Animal Husbandry Practices in Rural Bangladesh: Potential Risk Factors for Antimicrobial Drug Resistance and Emerging Diseases

    OpenAIRE

    Roess, Amira A.; Winch, Peter J.; Ali, Nabeel A.; Akhter, Afsana; Afroz, Dilara; El Arifeen, Shams; Darmstadt, Gary L.; Baqui, Abdullah H

    2013-01-01

    Antimicrobial drug administration to household livestock may put humans and animals at risk for acquisition of antimicrobial drug–resistant pathogens. To describe animal husbandry practices, including animal healthcare-seeking and antimicrobial drug use in rural Bangladesh, we conducted semi-structured in-depth interviews with key informants, including female household members (n = 79), village doctors (n = 10), and pharmaceutical representatives, veterinarians, and government officials (n = ...

  3. EARSS: European Antimicrobial Resistance Surveillance System; data from the Netherlands .Incidence and resistance rates for Streptococcus pneumoniae and Staphylococcus aureus

    NARCIS (Netherlands)

    Goettsch WG; Neeling AJ de; CIE; LIO

    2001-01-01

    In a porspective prevalence and incidence survey in The Netherlands in 1999 antimicrobial susceptibility data on invasive Streptococcus pneumoniae and Staphylococcus aureus infections were collected sithin the framework of European Antomicrobial Resistance Surveillance System (EARSS). The EARSS proj

  4. Occurrence, genetic characterization and antimicrobial resistance of Salmonella isolated from chicken meat and giblets.

    Science.gov (United States)

    Abd-Elghany, S M; Sallam, K I; Abd-Elkhalek, A; Tamura, T

    2015-04-01

    SUMMARY This study was undertaken to survey the presence of Salmonella in 200 chicken samples collected from Mansoura, Egypt. Salmonella was detected in 16% (8/50), 28% (14/50), 32% (16/50) and 60% (30/50) of whole chicken carcasses, drumsticks, livers and gizzards, respectively, with an overall prevalence of 34% (68/200) among all samples. One hundred and sixty-six isolates were identified biochemically as Salmonella, and confirmed genetically by PCR, based on the presence of invA and stn genes. The spvC gene, however, was detected in only 25.3% (42/166) of the isolates. Isolates were serotyped as Salmonella Enteritidis (37.3%), S. Typhimurium (30.1%), S. Kentucky (10.8%), S. Muenster (8.4%), S. Virchow (4.8%), S. Anatum (4.8%), S. Haifa (1.2%), and four were non-typable. Antimicrobial susceptibility tests of the Salmonella isolates revealed that 100% were resistant to each of erythromycin, penicillin, and amoxicillin, while 98.8%, 96.4%, 95.2%, and 91.6% were resistant to nalidixic acid, sulphamethoxazole, oxytetracycline, and ampicillin, respectively. Multidrug resistance was evident for 92.8% of the isolates. The high contamination level of chicken meat with multidrug-resistant Salmonella can constitute a problem for public health.

  5. Antimicrobial resistance in bacteria isolated from aquatic environments in Brazil: a systematic review

    Directory of Open Access Journals (Sweden)

    Ermeton Duarte do Nascimento

    2014-04-01

    Full Text Available This article discusses antibiotic resistance in bacteria isolated from aquatic environments in Brazil, taking into account isolation sites, the main reported antimicrobial agents, the genes involved in resistance, the most prevalent bacterial genera and species, and the main mechanisms of resistance. This review is based upon specialized literature, consulting published scientific articles selected from the SciELO, PubMed and LILACS databases. Based upon the inclusion criteria, we selected 21 articles, most (61.6% were from PubMed, with the highest prevalence for work done in the Southeast region (71.4% in freshwater environments (71.4%, and the major focus on farm ponds (28.6%. Gram-negative bacteria are the most studied (71.4% and the Aeromonas spp. was the one found most frequently (19.0%. The most frequently used antimicrobials were chloramphenicol (81.0%, gentamicin (76.2%, sulpha/trimethroprim (71.4%, ampicillin (61.9% and tetracycline (71.4%; and the ones with higher prevalence of resistance were chloramphenicol (58.8%, sulpha/trimethroprim (78.5% and ampicillin (84.6%. It was found that studies on resistance in other aquatic environments have not yet been conducted in Brazil, especially in the North and Northeast regions, where irregular rainfall distribution leads to the use of reservoirs as supply sources during the dry season, highlighting concerns regarding the quality, contamination and maintenance of these resources, as the water is intended for human use or for production purposes.

  6. EVALUATION OF MACROLIDE RESISTANCE AND DISTRIBUTION OF RESISTANT GENES IN STAPHYLOCOCCUS AUREUS BETWEEN, 2010 – 2013; A SYSTEMATIC REVIEW

    Directory of Open Access Journals (Sweden)

    MOHAMAD REZA HAVASIAN

    2015-01-01

    Full Text Available Objective: Staphylococci aureus and Coagulase-negative staphylococci (CoNS are a major source of infections associated with indwelling medical devices. Macrolide antimicrobial agents are widely used across the world to protect against bacterial infection. Methods: This is a systematic review study valuating all pubmed, science direct, Scopus and Google scholar articles about the Evaluation of macrolide resistance in Staphylococcus aureus between 2010 – 2013 using analytical statistical analysis. Data were collected and the related information extracted and put in statistical package and analyzed. Results: According the result of this study prevalence of macrolide resistant in some of region was more than other region and it caused by different conditions. The most common genes in macrolide resistant was erm(A but could not be found in regulatory region of the isolates. Conclusion: We should try to reduce the resistant to antimicrobial drug by set the healthy plane and reduce using of antimicrobial drug.

  7. Antimicrobial Drug Resistance of Vibrio cholerae, Democratic Republic of the Congo.

    Science.gov (United States)

    Miwanda, Berthe; Moore, Sandra; Muyembe, Jean-Jacques; Nguefack-Tsague, Georges; Kabangwa, Ickel Kakongo; Ndjakani, Daniel Yassa; Mutreja, Ankur; Thomson, Nicholas; Thefenne, Helene; Garnotel, Eric; Tshapenda, Gaston; Kakongo, Denis Kandolo; Kalambayi, Guy; Piarroux, Renaud

    2015-05-01

    We analyzed 1,093 Vibrio cholerae isolates from the Democratic Republic of the Congo during 1997-2012 and found increasing antimicrobial drug resistance over time. Our study also demonstrated that the 2011-2012 epidemic was caused by an El Tor variant clonal complex with a single antimicrobial drug susceptibility profile.

  8. Durable resistance to Puccinia triticina by accumulation of resistance genes

    Directory of Open Access Journals (Sweden)

    Bošković Jelena

    2009-01-01

    Full Text Available The individual use of single race-specific resistance genes with major phenotypic effects has rarely provided lasting resistance. However, breeding and combining or pyramiding of resistance genes into individual cultivars has had considerable success, particularly in situations in which the pathogen does not reproduce sexually, as in the case of wheat leaf rust pathogen. In European-Mediterranean region perfomed international investigations of wheat leaf rust proved that breeding of new lines of wheat resistant to Puccinia triticina Eriks. for differentiation of pathogen population, as well as for sources of durable resistance is necessary. Breeding of such resistant lines has proved necessary due to the unsatisfatory survey results of these regions on standard isogenic Lr lines. It has become clear that these regions needed new, more efficient differential resistance genes, as well as sources of resistance. In the beginning, after extensive screening tests of several International Rust Nurseries, 18 donors of resistance had been selected as crosses with recurrent parents' varieties Princ and Starke. These hybrid lines had been comparatively tested with twenty six Lr single gene lines using twenty especially virulent cultures of P. triticina in order to check the presence of these known Lr genes in our hybrid lines. Considerable influence of recurrent parent to the number of resistant genes in used donors was demonstrated. On the other hand, considerable influence of the pathogen culture was established to the number of resistance genes in used donors. In order to enhance resistance and pyramiding genes in these hybrids, the most interesting selected eight lines have been crossed with only effective isogenic ones, containing the strong genes Lr9, Lr19 and Lr24. On the basis of different segregation rations of all crossing combinations it was proved that no one of resistant donors contained the applied strong resistant genes. It means that our

  9. Antimicrobial resistance of 100 Salmonella strains isolated from Gallus gallus in 4 wilayas of Algeria.

    Science.gov (United States)

    Bounar-Kechih, S; Hamdi, T M; Mezali, L; Assaous, F; Rahal, K

    2012-05-01

    This study aims at identifying serotypes and surveying the antimicrobial resistance and plasmid support of resistance of 100 Salmonella strains, which were isolated from 96 out of 506 (18.97%) samples taken from different production farms in the wilayas (i.e., Algerian states) of Tizi-Ouzou, Bouira, Bejaïa, and Boumerdes in 2007. The highest percentage of Salmonella (48%) was recorded in Bouira. Thirteen serotypes were identified among the 100 Salmonella strains used in this study. The most prevalent ones were Salmonella Heidelberg (24%), Salmonella Enteritidis (20%), Salmonella Albany (16%), and Salmonella Typhimurium (9%). The strains showed resistance to 8 of the 34 antibiotics tested. Fifty-three percent of strains were resistant to at least one antibiotic, among which 15.09% were multiresistant. The most frequently observed resistance was to quinolones (58.49%), with a contribution of 94.74% of Salmonella Heidelberg resistant strains. The plasmid transfer performed on 53 strains showed that only 11 exhibited one or more markers of resistance, the most frequent being ampicillin, followed by tetracycline, then cotrimoxazole, sulphonamides, and kanamycin, in that order. The tetracycline characteristics were present in 72.72% of transconjugants, those of the β-lactams and sulphonamides in 27.27% each and those of the aminosides in 9.09%. The incompatibility groups of plasmids belong to the F1me and Com1 classes, and the molecular weight of the plasmid DNA was greater than 100 kb. The phenotypic and genotypic results indicate a clonal dissemination in the Gallus gallus species in this particular study; this phenomenon could generate resistant bacteria and transferable genes of resistance to humans.

  10. Antimicrobial resistance of 100 Salmonella strains isolated from Gallus gallus in 4 wilayas of Algeria.

    Science.gov (United States)

    Bounar-Kechih, S; Hamdi, T M; Mezali, L; Assaous, F; Rahal, K

    2012-05-01

    This study aims at identifying serotypes and surveying the antimicrobial resistance and plasmid support of resistance of 100 Salmonella strains, which were isolated from 96 out of 506 (18.97%) samples taken from different production farms in the wilayas (i.e., Algerian states) of Tizi-Ouzou, Bouira, Bejaïa, and Boumerdes in 2007. The highest percentage of Salmonella (48%) was recorded in Bouira. Thirteen serotypes were identified among the 100 Salmonella strains used in this study. The most prevalent ones were Salmonella Heidelberg (24%), Salmonella Enteritidis (20%), Salmonella Albany (16%), and Salmonella Typhimurium (9%). The strains showed resistance to 8 of the 34 antibiotics tested. Fifty-three percent of strains were resistant to at least one antibiotic, among which 15.09% were multiresistant. The most frequently observed resistance was to quinolones (58.49%), with a contribution of 94.74% of Salmonella Heidelberg resistant strains. The plasmid transfer performed on 53 strains showed that only 11 exhibited one or more markers of resistance, the most frequent being ampicillin, followed by tetracycline, then cotrimoxazole, sulphonamides, and kanamycin, in that order. The tetracycline characteristics were present in 72.72% of transconjugants, those of the β-lactams and sulphonamides in 27.27% each and those of the aminosides in 9.09%. The incompatibility groups of plasmids belong to the F1me and Com1 classes, and the molecular weight of the plasmid DNA was greater than 100 kb. The phenotypic and genotypic results indicate a clonal dissemination in the Gallus gallus species in this particular study; this phenomenon could generate resistant bacteria and transferable genes of resistance to humans. PMID:22499877

  11. Incidence, Antimicrobial Susceptibility, and Toxin Genes Possession Screening of Staphylococcus aureus in Retail Chicken Livers and Gizzards

    Directory of Open Access Journals (Sweden)

    Lubna S. Abdalrahman

    2015-04-01

    Full Text Available Few recent outbreaks in Europe and the US involving Campylobacter and Salmonella were linked to the consumption of chicken livers. Studies investigating Staphylococcus aureus in chicken livers and gizzards are very limited. The objectives of this study were to determine the prevalence, antimicrobial resistance, and virulence of S. aureus and MRSA (Methicillin-Resistant Staphylococcus aureus in retail chicken livers and gizzards in Tulsa, Oklahoma. In this study, 156 chicken livers and 39 chicken gizzards samples of two brands were collected. While one of the brands showed very low prevalence of 1% (1/100 for S. aureus in chicken livers and gizzards, the second brand showed prevalence of 37% (31/95. No MRSA was detected since none harbored the mecA or mecC gene. Eighty seven S. aureus isolates from livers and 28 from gizzards were screened for antimicrobial resistance to 16 antimicrobials and the possession of 18 toxin genes. Resistance to most of the antimicrobials screened including cefoxitin and oxacillin was higher in the chicken gizzards isolates. While the prevalence of enterotoxin genes seg and sei was higher in the gizzards isolates, the prevalence of hemolysin genes hla, hlb, and hld was higher in the livers ones. The lucocidin genes lukE-lukD was equally prevalent in chicken livers and gizzards isolates. Using spa typing, a subset of the recovered isolates showed that they are not known to be livestock associated and, hence, may be of a human origin. In conclusion, this study stresses the importance of thorough cooking of chicken livers and gizzards since it might contain multidrug resistant enterotoxigenic S. aureus. To our knowledge this is the first study to specifically investigate the prevalence of S. aureus in chicken livers and gizzards in the US.

  12. Obesity genes and insulin resistance

    Science.gov (United States)

    Belkina, Anna C.; Denis, Gerald V.

    2011-01-01

    Purpose of review The exploding prevalence of insulin resistance and Type 2 diabetes (T2D) linked to obesity has become an alarming public health concern. Worldwide, approximately 171 million people suffer from obesity-induced diabetes and public health authorities expect this situation to deteriorate rapidly. An interesting clinical population of ‘metabolically healthy but obese’ (MHO) cases is relatively protected from T2D and its associated cardiovascular risk. The molecular basis for this protection is not well understood but is likely to involve reduced inflammatory responses. The inflammatory cells and pathways that respond to overnutrition are the primary subject matter for this review. Recent findings The chance discovery of a genetic mutation in the Brd2 gene, which is located in the class II major histocompatibility complex and makes mice enormously fat but protects them from diabetes, offers revolutionary new insights into the cellular mechanisms that link obesity to insulin resistance and T2D. These Brd2-hypomorphic mice have reduced inflammation in fat that is normally associated with insulin resistance, and resemble MHO patients, suggesting novel therapeutic pathways for obese patients at risk for T2D. Summary Deeper understanding of the functional links between genes that control inflammatory responses to diet-induced obesity is crucial to the development of therapies for obese, insulin-resistant patients. PMID:20585247

  13. Modulation of antimicrobial host defense peptide gene expression by free fatty acids.

    Directory of Open Access Journals (Sweden)

    Lakshmi T Sunkara

    Full Text Available Routine use of antibiotics at subtherapeutic levels in animal feed drives the emergence of antimicrobial resistance. Development of antibiotic-alternative approaches to disease control and prevention for food animals is imperatively needed. Previously, we showed that butyrate, a major species of short-chain fatty acids (SCFAs fermented from undigested fiber by intestinal microflora, is a potent inducer of endogenous antimicrobial host defense peptide (HDP genes in the chicken (PLoS One 2011, 6: e27225. In the present study, we further revealed that, in chicken HD11 macrophages and primary monocytes, induction of HDPs is largely in an inverse correlation with the aliphatic hydrocarbon chain length of free fatty acids, with SCFAs being the most potent, medium-chain fatty acids moderate and long-chain fatty acids marginal. Additionally, three SCFAs, namely acetate, propionate, and butyrate, exerted a strong synergy in augmenting HDP gene expression in chicken cells. Consistently, supplementation of chickens with a combination of three SCFAs in water resulted in a further reduction of Salmonella enteritidis in the cecum as compared to feeding of individual SCFAs. More importantly, free fatty acids enhanced HDP gene expression without triggering proinflammatory interleukin-1β production. Taken together, oral supplementation of SCFAs is capable of boosting host immunity and disease resistance, with potential for infectious disease control and prevention in animal agriculture without relying on antibiotics.

  14. Clonal spread of antimicrobial-resistant Escherichia coli isolates among pups in two kennels

    Directory of Open Access Journals (Sweden)

    Takahashi Toshio

    2011-02-01

    Full Text Available Abstract Although the dog breeding industry is common in many countries, the presence of antimicrobial resistant bacteria among pups in kennels has been infrequently investigated. This study was conducted to better understand the epidemiology of antimicrobial-resistant Escherichia coli isolates from kennel pups not treated with antimicrobials. We investigated susceptibilities to 11 antimicrobials, and prevalence of extended-spectrum β-lactamase (ESBL in 86 faecal E. coli isolates from 43 pups in two kennels. Genetic relatedness among all isolates was assessed using pulsed-field gel electrophoresis (PFGE. Susceptibility tests revealed that 76% of the isolates were resistant to one or more of tested antimicrobials, with resistance to dihydrostreptomycin most frequently encountered (66.3% followed by ampicillin (60.5%, trimethoprim-sulfamethoxazole (41.9%, oxytetracycline (26.7%, and chloramphenicol (26.7%. Multidrug resistance, defined as resistance against two or more classes of antimicrobials, was observed in 52 (60.5% isolates. Three pups in one kennel harboured SHV-12 ESBL-producing isolates. A comparison between the two kennels showed that frequencies of resistance against seven antimicrobials and the variation in resistant phenotypes differed significantly. Analysis by PFGE revealed that clone sharing rates among pups of the same litters were not significantly different in both kennels (64.0% vs. 88.9%, whereas the rates among pups from different litters were significantly different between the two kennels (72.0% vs. 33.3%, P E. coli clones, including multidrug-resistant and ESBL-producing clones. It is likely that resistant and susceptible bacteria can clonally spread among the same and/or different litters thus affecting the resistance prevalence.

  15. 76 FR 14402 - Draft Action Plan-A Public Health Action Plan To Combat Antimicrobial Resistance

    Science.gov (United States)

    2011-03-16

    ... without change, including any personal or proprietary information provided. To download an electronic... reached with individual input from State and local health agencies, universities, professional societies... To Combat Antimicrobial Resistance AGENCY: Centers for Disease Control and Prevention...

  16. Prevalence and Incidence of Antimicrobial-Resistant Organisms among Hospitalized Inflammatory Bowel Disease Patients

    Directory of Open Access Journals (Sweden)

    Alon Vaisman

    2013-01-01

    Full Text Available BACKGROUND: Patients with inflammatory bowel disease (IBD experience frequent hospitalizations and use of immunosuppressive medications, which may predispose them to colonization with antimicrobial-resistant organisms (ARO.

  17. The changing epidemiology of bacteraemias in Europe : trends from the European Antimicrobial Resistance Surveillance System

    NARCIS (Netherlands)

    de Kraker, M. E. A.; Jarlier, V.; Monen, J. C. M.; Heuer, O. E.; van de Sande, N.; Grundmann, H.

    2013-01-01

    We investigated bacteraemia trends for five major bacterial pathogens, Staphylococcus aureus, Escherichia coli, Streptococcus pneumoniae, Enterococcus faecalis and Enterococcus faecium, and determined how expanding antimicrobial resistance influenced the total burden of bacteraemias in Europe. Aetio

  18. Pharmacokinetic-Pharmacodynamic Model To Evaluate Intramuscular Tetracycline Treatment Protocols To Prevent Antimicrobial Resistance in Pigs

    DEFF Research Database (Denmark)

    Ahmad, Amais; Græsbøll, Kaare; Christiansen, Lasse Engbo;

    2015-01-01

    to which resistant strains outcompete susceptible strains under antimicrobial pressure may depend not only on the antimicrobial treatment strategies but also on the epidemiological parameters, such as the composition of the bacterial strains in a pig. This study evaluated how variation in the dosing...... protocol for intramuscular administration of tetracycline and the composition of bacterial strains in a pig affect the level of resistance in the intestine of a pig. Predictions were generated by a mathematical model of competitive growth of Escherichia coli strains in pigs under specified plasma......High instances of antimicrobial resistance are linked to both routine and excessive antimicrobial use, but excessive or inappropriate use represents an unnecessary risk. The competitive growth advantages of resistant bacteria may be amplified by the strain dynamics; in particular, the extent...

  19. Antimicrobial use in aquaculture re-examined: its relevance to antimicrobial resistance and to animal and human health.

    Science.gov (United States)

    Cabello, Felipe C; Godfrey, Henry P; Tomova, Alexandra; Ivanova, Larisa; Dölz, Humberto; Millanao, Ana; Buschmann, Alejandro H

    2013-07-01

    The worldwide growth of aquaculture has been accompanied by a rapid increase in therapeutic and prophylactic usage of antimicrobials including those important in human therapeutics. Approximately 80% of antimicrobials used in aquaculture enter the environment with their activity intact where they select for bacteria whose resistance arises from mutations or more importantly, from mobile genetic elements containing multiple resistance determinants transmissible to other bacteria. Such selection alters biodiversity in aquatic environments and the normal flora of fish and shellfish. The commonality of the mobilome (the total of all mobile genetic elements in a genome) between aquatic and terrestrial bacteria together with the presence of residual antimicrobials, biofilms, and high concentrations of bacteriophages where the aquatic environment may also be contaminated with pathogens of human and animal origin can stimulate exchange of genetic information between aquatic and terrestrial bacteria. Several recently found genetic elements and resistance determinants for quinolones, tetracyclines, and β-lactamases are shared between aquatic bacteria, fish pathogens, and human pathogens, and appear to have originated in aquatic bacteria. Excessive use of antimicrobials in aquaculture can thus potentially negatively impact animal and human health as well as the aquatic environment and should be better assessed and regulated.

  20. Antimicrobial resistance of zoonotic and commensal bacteria in Europe: The missing link between consumption and resistance in veterinary medicine

    DEFF Research Database (Denmark)

    Garcia-Migura, Lourdes; Hendriksen, Rene S.; Fraile, Lorenzo;

    2014-01-01

    The emergence of resistance in food animals has been associated to the consumption of antimicrobials in veterinary medicine. Consequently, monitoring programs have been designed to monitor the occurrence of antimicrobial resistant bacteria. This study analyses the amount of antimicrobial agents...... used in nine European countries from 2005 to 2011, and compares by univariate analysis the correlations between consumptions of each of the following antimicrobial classes; tetracycline, penicillins, cephalosporins, quinolones and macrolides. An overview of resistance in zoonotic and commensal bacteria...... in Europe focusing on Salmonella, Escherichia coli, Campylobacter sp. and Enterococcus sp., during the same period of time based on monitoring programs is also assessed. With the exception of cephalosporins, linear regressions showed strong positive associations between the consumption of the four different...

  1. Bovine salmonellosis in Northeast of Iran: Frequency, genetic fingerprinting and antimicrobial resistance patterns of Salmonella spp.

    Directory of Open Access Journals (Sweden)

    Hessam A. Halimi

    2014-01-01

    Conclusion: The emergence of multiple antibiotic-resistant strains of Salmonella Typhimurium should be of great concern to the public. No correlation between ERIC fingerprinting and resistance patterns of Salmonella isolates was found, which indicates resistance to antimicrobial agents was not related to specific genetic background.

  2. Duration of colonization with antimicrobial-resistant bacteria after ICU discharge

    NARCIS (Netherlands)

    Haverkate, Manon R; Derde, Lennie P G; Brun-Buisson, Christian; Bonten, Marc J M; Bootsma, Martin C J

    2014-01-01

    PURPOSE: Readmission of patients colonized with antimicrobial-resistant bacteria (AMRB) is important in the nosocomial dynamics of AMRB. We assessed the duration of colonization after discharge from the intensive care unit (ICU) with highly resistant Enterobacteriaceae (HRE), methicillin-resistant S

  3. Associations of Streptococcus suis serotype 2 ribotype profiles with clinical disease and antimicrobial resistance

    DEFF Research Database (Denmark)

    Rasmussen, S. R.; Aarestrup, Frank Møller; Jensen, N. E.;

    1999-01-01

    A total of 122 Streptococcus suis serotype 2 strains were characterized thoroughly by comparing clinical and pathological observations, ribotype profiles, and antimicrobial resistance. Twenty-one different ribotype profiles were found and compared by cluster analysis, resulting in the identificat......A total of 122 Streptococcus suis serotype 2 strains were characterized thoroughly by comparing clinical and pathological observations, ribotype profiles, and antimicrobial resistance. Twenty-one different ribotype profiles were found and compared by cluster analysis, resulting in the...

  4. PREVALENCE AND ANTIMICROBIAL RESISTANCE ASSESSMENT OF SUBCLINICAL MASTITIS IN MILK SAMPLES FROM SELECTED DAIRY FARMS

    OpenAIRE

    Murugaiyah Marimuthu; Faez Firdaus Jesse Abdullah; Konto Mohammed; Sangeetha D/O Sarvananthan Poshpum; Lawan Adamu; Abdinasir Yusuf Osman; Yusuf Abba; Abdulnasir Tijjani

    2014-01-01

    This study was conducted in order to determine the prevalence and bacteriological assessment of subclinical mastitis and antimicrobial resistance of bacterial isolates from dairy cows in different farms around Selangor, Malaysia. A total of 120 milk samples from 3 different farms were randomly collected and tested for subclinical mastitis using California Mastitis Test (CMT), as well as for bacterial culture for isolation, identification and antimicrobial resistance. The most prevalent bacter...

  5. ANTIMICROBIAL RESISTANT PATTERN OF FECAL ESCHERICHIA COLI IN SELECTED BROILER FARMS OF EASTERN HARARGE ZONE, ETHIOPIA

    Directory of Open Access Journals (Sweden)

    Tesfaheywet Zeryehun

    2013-12-01

    Full Text Available A study was conducted to determine the pattern of antimicrobial resistance in Escherichia coli isolated from Cloacal swab of broiler chickens in selected farms of Eastern Harrarge zone of Ethiopia. Isolation and identification of Escherichia coli were done by using enrichment media, selective media, and biochemical tests. 65 selected isolates were subjected to 9 antimicrobial agents to determine their resistance by the disk diffusion method. Accordingly, the resistance of E.coli was tetracycline (90%, streptomycin (78%, ampicillin (60%, amoxicillin (56%, erythromycin (45%, ciprofloxacin (38%, and chloramphenicol (15%. None of the isolates showed resistance to gentamicin. Sensitivity was observed in case of 80%, 77%, 44%, 32%, 26%, 20%, 20%, 15%, and 10% of the isolates for chloramphenicol, gentamicin, ciprofloxacin, amoxicillin, ampicillin, streptomycin, erythromycin, and tetracycline, respectively. Intermediate resistance/susceptibility was recorded for 5-35% of the isolates. 92.3% of the isolates tested showed multidrug resistance for 2 or more antimicrobials and the highest levels (18.5% of multidrug-resistant E. coli were observed for 3 antimicrobials accounting 7.7% for tetracycline-ampicillin-streptomycin and 10.8% for tetracycline-ampicillin-amoxicillin. This study showed resistance against the antibiotics that are commonly used in poultry. Furthermore, it was concluded that gentamicin, chloramphenicole and ciproflaxin will be the first drugs of choice to resist infections caused by E. coli in chicken in Ethiopia. These findings confirm significant increase in the incidence of antimicrobial resistance in the E. coli isolates which is most probably due to increased use of antibiotics as feed additives for growth promotion and prevention of diseases and use of inappropriate antibiotics for treatment of diseases. Hence, excess or abusive use of antimicrobials should be guarded through judicious application of antimicrobials

  6. Serotypes and Antimicrobial Resistance of Human Nontyphoidal Isolates of Salmonella enterica from Crete, Greece

    Directory of Open Access Journals (Sweden)

    Sofia Maraki

    2014-01-01

    Full Text Available We report on the serotype distribution and the antimicrobial resistance patterns to 20 different antimicrobials of 150 Salmonella enterica strains isolated from stools of diarrhoeal patients on the island of Crete over the period January 2011-December 2012. Among the S. enterica serotypes recovered, Enteritidis was the most prevalent (37.3%, followed by Typhimurium (28.7% and Newport (8.7%. No resistance was detected to extended-spectrum cephalosporins and carbapenems. Rates of resistance to ampicillin, amoxicillin/clavulanic acid, chloramphenicol, tetracycline, and cotrimoxazole were 9.3%, 4%, 2%, 15.3%, and 8.7%, respectively. Resistance to ≥4 antibiotics was primarily observed for serotypes Typhimurium and Hadar. Enteritidis remains the predominant serotype in Crete. Although low resistance to most antimicrobials was detected, continued surveillance of susceptibility is needed due to the risk of resistance.

  7. Biotic stress resistance in agriculture through antimicrobial peptides.

    Science.gov (United States)

    Sarika; Iquebal, M A; Rai, Anil

    2012-08-01

    Antimicrobial peptides (AMPs) are the hosts' defense molecules against microbial pathogens and gaining extensive research attention worldwide. These have been reported to play vital role of host innate immunity in response to microbial challenges. AMPs can be used as a natural antibiotic as an alternative of their chemical counterpart for protection of plants/animals against diseases. There are a number of sources of AMPs including prokaryotic and eukaryotic organisms and are present, both in vertebrates and invertebrates. AMPs can be classified as cationic or anionic, based on net charges. Large number of databases and tools are available in the public domain which can be used for development of new genetically modified disease resistant varieties/breeds for agricultural production. The results of the biotechnological research as well as genetic engineering related to AMPs have shown high potential for reduction of economic losses of agricultural produce due to pathogens. In this article, an attempt has been made to introduce the role of AMPs in relation to plants and animals. Their functional and structural characteristics have been described in terms of its role in agriculture. Different sources of AMPs and importance of these sources has been reviewed in terms of its availability. This article also reviews the bioinformatics resources including different database tools and algorithms available in public domain. References of promising biotechnology research in relation to AMPs, prospects of AMPs for further development of genetically modified varieties/breeds are highlighted. AMPs are valuable resource for students, researchers, educators and medical and industrial personnel.

  8. The evolution of resistance gene in plants

    Institute of Scientific and Technical Information of China (English)

    BEN Haiyan; LIU Xuemin; LI Lijun; LIU Li

    2007-01-01

    Resistance genes enable plants to fight against plant pathogens. Plant resistance genes (R gene) are organized complexly in genome. Some resistance gene sequence data enable an insight into R gene structure and gene evolution. Some sites like Leucine-Rich Repeat (LRR) are of specific interest since homologous recombination can happen. Crossing over, transposon insertion and excision and mutation can produce new specificity. Three models explaining R gene evolution were discussed. More information needed for dissection of R gene evolution though some step can be inferred from genetic and sequence analysis.

  9. Superbugs: should antimicrobial resistance be included as a cost in economic evaluation?

    Science.gov (United States)

    Coast, J; Smith, R D; Millar, M R

    1996-01-01

    This paper argues that increasing resistance to antimicrobials is an important social externality that has not been captured at the level of economic appraisal. The paper explicitly considers reasons why the externality of antimicrobial resistance has not generally been included as a cost in economic evaluations comparing management strategies for infectious diseases. Four reasons are considered: first, that the absolute cost of antimicrobial resistance is too small to be worth including; second, that there is an implicit discounting of the costs of antimicrobial resistance on the basis of time preference which makes the cost too small to be worth including; third, that there is an implicit discounting of the costs of antimicrobial resistance on the basis of uncertainty which makes the cost too small to be worth including; and fourth, that the costs are too difficult to measure. Although there does not appear to be methodological justification for excluding the costs of antimicrobial resistance, it seems likely that, because of the practical difficulties associated with measuring these costs, they will continue to be ignored. The paper concludes with a discussion of the applicability of standard policy responses used to deal with externalities in other areas of welfare economics.

  10. Antimicrobial Resistance of Shigella flexneri Serotype 1b Isolates in China.

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    Xianyan Cui

    Full Text Available Shigella flexneri serotype 1b is among the most prominent serotypes in developing countries, followed by serotype 2a. However, only limited data is available on the global phenotypic and genotypic characteristics of S. flexneri 1b. In the present study, 40 S. flexneri 1b isolates from different regions of China were confirmed by serotyping and biochemical characterization. Antimicrobial susceptibility testing showed that 85% of these isolates were multidrug-resistant strains and antibiotic susceptibility profiles varied between geographical locations. Strains from Yunnan were far more resistant than those from Xinjiang, while only one strain from Shanghai was resistant to ceftazidime and aztreonam. Fifteen cephalosporin resistant isolates were identified in this study. ESBL genes (blaSHV, blaTEM, blaOXA, and blaCTX-M and ampC genes (blaMOX, blaFOX, blaMIR(ACT-1, blaDHA, blaCIT and blaACC were subsequently detected among the 15 isolates. The results showed that these strains were positive only for blaTEM, blaOXA, blaCTX-M, intI1, and intI2. Furthermore, pulsed-field gel electrophoresis (PFGE analysis showed that the 40 isolates formed different profiles, and the PFGE patterns of Xinjiang isolates were distinct from Yunnan and Shanghai isolates by one obvious, large, missing band. In summary, similarities in resistance patterns were observed in strains with the same PFGE pattern. Overall, the results supported the need for more prudent selection and use of antibiotics in China. We suggest that antibiotic susceptibility testing should be performed at the start of an outbreak, and antibiotic use should be restricted to severe Shigella cases, based on resistance pattern variations observed in different regions. The data obtained in the current study might help to develop a strategy for the treatment of infections caused by S. flexneri 1b in China.

  11. Antimicrobial resistance and molecular analysis of methicillin-resistant Staphylococcus aureus collected in a Spanish hospital.

    Science.gov (United States)

    Hernández-Porto, Miriam; Lecuona, María; Aguirre-Jaime, Armando; Castro, Beatriz; Delgado, Teresa; Cuervo, Milagros; Pedroso, Yanet; Arias, Ángeles

    2015-04-01

    Clonal distribution of methicillin-resistant Staphylococcus aureus (MRSA) in hospitals may differ according to the geographic location and time period. Knowledge of MRSA clonal epidemiology in hospital settings involves much more than the study of healthcare-associated MRSA (HA-MRSA) clones. In recent years, investigators have documented the introduction of both community-associated MRSA (CA-MRSA) and livestock-associated MRSA (LA-MRSA) clones, the emergence of clones carrying Staphylococcal cassette chromosome mec (SCCmec) XI, and the genetic diversity among sporadic MRSA isolates. The allocation of certain antibiotypes to dominant MRSA clones in an institution allows their use as phenotypic markers for a preliminary search for new clones, early detection of clonal shift, and as a guide for better empirical therapy, infection control, and treatment within a particular institution. For these reasons, we identified 938 strains detected in a System of Universal Active Surveillance of MRSA in clinical samples during the period 2009-2010, obtaining the clonal distribution of MRSA at the Hospital Universitario de Canarias (Tenerife, Spain) and the relationship between antimicrobial susceptibility and three major clones present. The antibiotypes that best defined the ST5-MRSA-IV (Pediatric) clone showed resistance to tobramycin and susceptibility to clindamycin, erythromycin, gentamicin, rifampin, trimethoprim-sulfamethoxazole, vancomycin, quinupristin/dalfopristin, and linezolid, whereas the ST22-MRSA-IV clone (EMRSA-15) showed susceptibility to these antibiotics, and finally, the ST36-MRSA-II clone (EMRSA-16) was resistant to clindamycin, erythromycin, and tobramycin and susceptible to the remaining antimicrobials. Similar observations would allow the early detection of changes in clonal epidemiology by analysis of antimicrobial susceptibility of the isolates within a single institution. PMID:25365597

  12. Virulence and Antimicrobial Resistance in Enterococci Isolated from Urinary Tract Infections

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    Ahad Bazmani

    2013-02-01

    Full Text Available Purpose: Urinary tract infection (UTI is the most common nosocomial infection among hospitalized patients. Meanwhile, most frequent infections involving enterococci affect the urinary tract. The aims of this study were to investigate the susceptibility pattern of isolated enterococci from UTI and the prevalence of virulence genes. Methods: The study used enterococci isolated from urinary tract infections obtained from 3 university teaching hospitals in Northwest Iran. The antimicrobial susceptibility of the strains was determined using the disc diffusion method. Multiplex PCR was performed for the detection of genus- species specific targets, and potential virulence genes. Results: Of 188 enterococcal isolates, 138 (73.4% and 50 (26.6% were Enterococcus faecalis and E. faecium, respectively. Antibiotic susceptibility testing showed high resistance to amikacin (86.2%, rifampicin (86.2% and erythromycin (73.9%, irrespective of species. In total, 68.1% were positive for gelE, and 57.4%, 53.2%, 56.4%, and 52.1% of isolates were positive for cpd, asa1, ace, and esp, respectively. Conclusion: The study revealed that most of UTI isolates were multidrug resistance against the antibiotics tested and antibiotic resistance was more common among E. faecium isolates than E. faecalis. A significant correlation was found between UTI and the presence of gelE among E. faecalis strains (p < 0.001.

  13. Antimicrobial treatment of nosocomial meticillin-resistant Staphylococcus aureus (MRSA) pneumonia: current and future options.

    Science.gov (United States)

    Welte, Tobias; Pletz, Mathias W

    2010-11-01

    Meticillin-resistant Staphylococcus aureus (MRSA) is a frequent cause of nosocomial pneumonia. Inadequate or inappropriate antimicrobial therapy, often caused by antimicrobial resistance, is associated with increased mortality for these infections. Agents currently recommended for the treatment of MRSA pneumonia include vancomycin and linezolid in the USA, and vancomycin, linezolid, teicoplanin and quinupristin/dalfopristin in Europe. Antimicrobials such as tigecycline and daptomycin, although approved for the treatment of some MRSA infections, have not demonstrated efficacy equivalent to the approved agents for MRSA pneumonia. Further agents lack data from randomised controlled trials (e.g. fosfomycin, fusidic acid or rifampicin in combination with vancomycin). Antimicrobial agents that have recently been approved or are being investigated as treatments for MRSA infections include the lipoglycopeptides telavancin (approved for the treatment of complicated skin and skin-structure infections in the USA and Canada), dalbavancin and oritavancin, the cephalosporins ceftobiprole and ceftaroline, and the dihydrofolate reductase inhibitor iclaprim. To be an effective treatment for MRSA pneumonia, antimicrobial agents must have activity against antimicrobial-resistant S. aureus, penetrate well into the lung, have a low potential for resistance development and have a good safety profile. Here, the available data for current and potential future MRSA pneumonia antimicrobials are reviewed and discussed. PMID:20724119

  14. Prevalence and Antimicrobial Resistance in Escherichia coli from Food Animals in Lagos, Nigeria.

    Science.gov (United States)

    Adenipekun, Eyitayo O; Jackson, Charlene R; Oluwadun, Afolabi; Iwalokun, Bamidele A; Frye, Jonathan G; Barrett, John B; Hiott, Lari M; Woodley, Tiffanie A

    2015-06-01

    Foodborne bacteria are often associated with human infections; these infections can become more complicated to treat if the bacteria are also resistant to antimicrobials. In this study, prevalence, antimicrobial resistance, and genetic relatedness of Escherichia coli among food producing animals from Lagos, Nigeria, was investigated. From December 2012 to June 2013, E. coli were isolated from fecal samples of healthy cattle, chicken, and swine. Antimicrobial susceptibility testing against 22 antimicrobials was performed using broth microdilution with the Sensititre™ system. Clonal types were determined by pulsed-field gel electrophoresis (PFGE). From the analysis, 211/238 (88.7%), 170/210 (81%), and 136/152 (89.5%) samples from cattle, chicken, and swine, respectively, were positive for E. coli. A subset of those isolates (n=211) selected based on β-lactamase production was chosen for further study. Overall, E. coli exhibited the highest resistance to tetracycline (124/211; 58.8%), trimethoprim/sulfamethoxazole (84/211; 39.8%), and ampicillin (72/211; 34.1%). Approximately 40% of the isolates were pan-susceptible, and none of the isolates were resistant to amikacin, cefepime, ceftazidime, ertapenem, meropenem, or tigecycline. Among the resistant isolates, 28 different resistance patterns were observed; 26 of those were characterized as multi-drug resistant (MDR; resistance to ≥2 antimicrobials). One isolate was resistant to 13 different antimicrobials representing five different antimicrobial classes. Using PFGE, MDR E. coli were genetically diverse and overall did not group based on source; identical PFGE patterns were detected among isolates from different sources. These results suggest that isolates cannot be attributed to specific sources, and some may be present across all of the sources. Results from this study indicate that food-producing animals in Nigeria are a reservoir of MDR E. coli that may be transferred to humans via the food chain. PMID

  15. Molecular epidemiology, antimicrobial susceptibilities and resistance mechanisms of Streptococcus pyogenes isolates resistant to erythromycin and tetracycline in Spain (1994–2006

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    Rubio-López Virginia

    2012-09-01

    Full Text Available Abstract Background Group A Streptococcus (GAS causes human diseases ranging in severity from uncomplicated pharyngitis to life-threatening necrotizing fasciitis and shows high rates of macrolide resistance in several countries. Our goal is to identify antimicrobial resistance in Spanish GAS isolates collected between 1994 and 2006 and to determine the molecular epidemiology (emm/T typing and PFGE and resistance mechanisms of those resistant to erythromycin and tetracycline. Results Two hundred ninety-five out of 898 isolates (32.8% were erythromycin resistant, with the predominance of emm4T4, emm75T25, and emm28T28, accounting the 67.1% of the 21 emm/T types. Spread of emm4T4, emm75T25 and emm28T28 resistant clones caused high rates of macrolide resistance. The distribution of the phenotypes was M (76.9%, cMLSB (20.3%, iMLSB (2.7% with the involvement of the erythromycin resistance genes mef(A (89.5%, msr(D (81.7%, erm(B (37.3% and erm(A (35.9%. Sixty-one isolates were tetracycline resistant, with the main representation of the emm77T28 among 20 emm/T types. To note, the combination of tet(M and tet(O tetracycline resistance genes were similar to tet(M alone reaching values close to 40%. Resistance to both antibiotics was detected in 19 isolates of 7 emm/T types, being emm11T11 and the cMLSB phenotype the most frequent ones. erm(B and tet(M were present in almost all the strains, while erm(A, mef(A, msr(D and tet(O appeared in less than half of them. Conclusions Spanish GAS were highly resistant to macrolides meanwhile showed minor resistance rate to tetracycline. A remarkable correlation between antimicrobial resistance and emm/T type was noticed. Clonal spread of emm4T4, emm75T25 and emm28T28 was the main responsable for macrolide resistance where as that emm77T28 clones were it to tetraclycline resistance. A wide variety of macrolide resistance genes were responsible for three macrolide resistance phenotypes.

  16. Trends in antimicrobial resistance among clinical isolates of enterococci in a Brazilian tertiary hospital: a 4-year study

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    Natália Conceição

    2011-04-01

    Full Text Available INTRODUCTION: In the past two decades members of the genus Enterococcus have emerged as important nosocomial pathogens worldwide. This study prospectively analyzed the distribution of species and trends in antimicrobial resistance among clinical isolates of enterococci in a Brazilian tertiary hospital from 2006-2009. METHODS: Enterococcal species were identified by conventional biochemical tests. The antimicrobial susceptibility profile was performed by disk diffusion in accordance with the Clinical and Laboratory Standards Institute (CLSI. A screening test for vancomycin was also performed. Minimal inhibitory concentration (MIC for vancomycin was determined using the broth dilution method. Molecular assays were used to confirm speciation and genotype of vancomycin-resistant enterococci (VRE. RESULTS: A total of 324 non-repetitive enterococcal isolates were recovered, of which 87% were E. faecalis and 10.8% E. faecium. The incidence of E. faecium per 1,000 admissions increased significantly (p 256µg/ mL and harbored vanA genes. The majority (89.5% of VRE belonged to E. faecium species, which were characteristically resistant to ampicillin and quinolones. Overall, ampicillin resistance rate increased significantly from 2.5% to 21.4% from 2006-2009. Resistance rates for gentamicin, chloramphenicol, tetracycline, and erythromycin significantly decreased over time, although they remained high. Quinolones resistance rates were high and did not change significantly over time. CONCLUSIONS: The data obtained show a significant increasing trend in the incidence of E. faecium resistant to ampicillin and vancomycin.

  17. Assessment of species and antimicrobial resistance among Enterobacteriaceae isolated from mallard duck faeces.

    Science.gov (United States)

    Murugaiyan, Jayaseelan; Krueger, Karolin; Roesler, Uwe; Weinreich, Joerg; Schierack, Peter

    2015-03-01

    Mallard ducks have demonstrated to be a likely reservoir for zoonotic E. coli strains; thus, it is possible that these ducks could also act as a reservoir for other Enterobacteriaceae members. The present study was initiated to evaluate the species distribution of Enterobacteriaceae other than E. coli in 175 fresh faecal samples collected from a population of mallard ducks. Sixty-four samples displayed detectable colonies of Enterobacteriaceae (excluding E. coli), which resulted in 75 pulsed-field gel electrophoresis (PFGE) types. Seventy-five single representatives of each PFGE type were subjected to identification with API 32NE and MALDI TOF MS systems due to the practical difficulties in species differentiation of Enterobacteriaceae. Those isolated were found to be from nine genera: Buttiauxella (15 %), Citrobacter (5 %), Enterobacter (32 %), Hafnia (1 %), Leclercia (1 %), Pantoea (7 %), Raoultella (21 %), Rahnella (7 %) and Serratia (11 %). Evaluation of antimicrobial resistance phenotypes using the disc method and detection of resistance genes using the microarray method revealed that these microbes possess resistance to β-lactams, aminoglycosides, macrolides, quinolones, rifamycine, sulphonamides, streptogramins and diaminopyrimidines. In conclusion, mallard ducks harbour a variety of non-pathogenic and pathogenic Enterobacteriaceae species like Enterobacter cloacae and Enterobacter amnigenus in their intestine and could act as a reservoir of resistant Enterobacteriaceae.

  18. Antibiotic resistance genes detected in the marine sponge Petromica citrina from Brazilian coast.

    Science.gov (United States)

    Laport, Marinella Silva; Pontes, Paula Veronesi Marinho; Dos Santos, Daniela Silva; Santos-Gandelman, Juliana de Fátima; Muricy, Guilherme; Bauwens, Mathieu; Giambiagi-deMarval, Marcia; George, Isabelle

    2016-01-01

    Although antibiotic-resistant pathogens pose a significant threat to human health, the environmental reservoirs of the resistance determinants are still poorly understood. This study reports the detection of resistance genes (ermB, mecA, mupA, qnrA, qnrB and tetL) to antibiotics among certain culturable and unculturable bacteria associated with the marine sponge Petromica citrina. The antimicrobial activities elicited by P. citrina and its associated bacteria are also described. The results indicate that the marine environment could play an important role in the development of antibiotic resistance and the dissemination of resistance genes among bacteria. PMID:27287338

  19. Prevalence, molecular characterization and antimicrobial resistance of Salmonella serovars isolated from northwestern Spanish broiler flocks (2011-2015).

    Science.gov (United States)

    Lamas, A; Fernandez-No, I C; Miranda, J M; Vázquez, B; Cepeda, A; Franco, C M

    2016-09-01

    The present study investigated the prevalence, antimicrobial resistance to twenty antibiotics, and class 1 integron and virulence genes of Salmonella isolated from poultry houses of broilers in northwestern Spain between 2011 and 2015. Strains were classified to the serotype level using the Kauffman-White typing scheme and subtyping with enterobacterial repetitive intergenic consensus PCR. The prevalence of Salmonella spp. was 1.02%. Sixteen different serotypes were found, with S. typhimurium and S. arizonae 48:z4, z23:- being the most prevalent. A total of 59.70% of strains were resistant to at least one, and 19.70% were resistant to multiple drugs. All Salmonella spp. were susceptible to cefotaxime, ciprofloxacin, gentamicin, kanamycin, levofloxacin, neomycin, and trimethoprim. The highest level of resistance was to sulfamethoxazole (40.29%), doxycycline (17.91%), and nalidixic acid (17.91%). None of the isolates carried class 1 integron and only isolates of S. enterica subspecies enterica were positive for all virulence factors tested, whereas S. arizonae lacked genes related to replication and invasion in nonphagocytic cells. This study demonstrates that the prevalence and antimicrobial resistance of Salmonella spp. in poultry houses of broilers of northwestern Spain is low compared with those found in other studies and in other steps of the food chain. PMID:27143768

  20. Isolation and characterization of antimicrobial-resistant Escherichia coli from national horse racetracks and private horse-riding courses in Korea

    Science.gov (United States)

    Chung, Yeon Soo; Song, Jae Won; Kim, Dae Ho; Shin, Sook; Park, Young Kyung; Yang, Soo Jin; Lim, Suk Kyung

    2016-01-01

    Limited information is available regarding horse-associated antimicrobial resistant (AR) Escherichia (E.) coli. This study was designed to evaluate the frequency and characterize the pattern of AR E. coli from healthy horse-associated samples. A total of 143 E. coli (4.6%) were isolated from 3,078 samples collected from three national racetracks and 14 private horse-riding courses in Korea. Thirty of the E. coli isolates (21%) showed antimicrobial resistance to at least one antimicrobial agent, and four of the AR E. coli (13.3%) were defined as multi-drug resistance. Most of the AR E. coli harbored AR genes corresponding to their antimicrobial resistance phenotypes. Four of the AR E. coli carried class 1 integrase gene (intI1), a gene associated with multi-drug resistance. Pulsed-field gel electrophoretic analysis showed no genetic relatedness among AR E. coli isolated from different facilities; however, cross-transmissions between horses or horses and environments were detected in two facilities. Although cross-transmission of AR E. coli in horses and their environments was generally low, our study suggests a risk of transmission of AR bacteria between horses and humans. Further studies are needed to evaluate the risk of possible transmission of horse-associated AR bacteria to human communities through horse riders and horse-care workers. PMID:26645344

  1. Isolation and characterization of antimicrobial-resistant Escherichia coli from national horse racetracks and private horse-riding courses in Korea.

    Science.gov (United States)

    Chung, Yeon Soo; Song, Jae Won; Kim, Dae Ho; Shin, Sook; Park, Young Kyung; Yang, Soo Jin; Lim, Suk Kyung; Park, Kun Taek; Park, Yong Ho

    2016-06-30

    Limited information is available regarding horse-associated antimicrobial resistant (AR) Escherichia (E.) coli. This study was designed to evaluate the frequency and characterize the pattern of AR E. coli from healthy horse-associated samples. A total of 143 E. coli (4.6%) were isolated from 3,078 samples collected from three national racetracks and 14 private horse-riding courses in Korea. Thirty of the E. coli isolates (21%) showed antimicrobial resistance to at least one antimicrobial agent, and four of the AR E. coli (13.3%) were defined as multi-drug resistance. Most of the AR E. coli harbored AR genes corresponding to their antimicrobial resistance phenotypes. Four of the AR E. coli carried class 1 integrase gene (intI1), a gene associated with multi-drug resistance. Pulsed-field gel electrophoretic analysis showed no genetic relatedness among AR E. coli isolated from different facilities; however, cross-transmissions between horses or horses and environments were detected in two facilities. Although cross-transmission of AR E. coli in horses and their environments was generally low, our study suggests a risk of transmission of AR bacteria between horses and humans. Further studies are needed to evaluate the risk of possible transmission of horse-associated AR bacteria to human communities through horse riders and horse-care workers. PMID:26645344

  2. Pilot Screening to Determine Antimicrobial Synergies in a Multidrug-Resistant Bacterial Strain Library

    Science.gov (United States)

    Kim, Si-Hyun; Park, Chulmin; Chun, Hye-Sun; Choi, Jae-Ki; Lee, Hyo-Jin; Cho, Sung-Yeon; Park, Sun Hee; Choi, Su-Mi; Choi, Jung-Hyun; Yoo, Jin-Hong

    2016-01-01

    With the rise in multidrug-resistant (MDR) bacterial infections, there has been increasing interest in combinations of ≥2 antimicrobial agents with synergistic effects. We established an MDR bacterial strain library to screen for in vitro antimicrobial synergy by using a broth microdilution checkerboard method and high-throughput luciferase-based bacterial cell viability assay. In total, 39 MDR bacterial strains, including 23 carbapenem-resistant gram-negative bacteria, 9 vancomycin-intermediate Staphylococcus aureus, and 7 vancomycin-resistant Enterococcus faecalis, were used to screen for potential antimicrobial synergies. Synergies were more frequently identified with combinations of imipenem plus trimethoprim–sulfamethoxazole for carbapenem-resistant Acinetobacter baumannii in the library. To verify this finding, we tested 34 A. baumannii clinical isolates resistant to both imipenem and trimethoprim–sulfamethoxazole by the checkerboard method. The imipenem plus trimethoprim–sulfamethoxazole combination showed synergy in the treatment of 21 (62%) of the clinical isolates. The results indicate that pilot screening for antimicrobial synergy in the MDR bacterial strain library could be valuable in the selection of combination therapeutic regimens to treat MDR bacterial infections. Further studies are warranted to determine whether this screening system can be useful to screen for the combined effects of conventional antimicrobials and new-generation antimicrobials or nonantimicrobials. PMID:26974861

  3. Antimicrobial susceptibility of Staphylococcus aureus and characterization of methicillin-resistant Staphylococcus aureus isolated from bovine mastitis in Korea.

    Science.gov (United States)

    Nam, Hyang-Mi; Lee, Ae-Li; Jung, Suk-Chan; Kim, Mal-Nam; Jang, Geum-Chan; Wee, Sung-Hwan; Lim, Suk-Kyung

    2011-02-01

    A total of 402 Staphylococcus aureus isolates from bovine mastitis milk collected during 2003-2009 in Korea were tested for susceptibility to 20 antimicrobial agents. All S. aureus isolates were susceptible to 11 of 20 antimicrobials tested; no resistance was observed against pirlimycin, telithromycin, novobiocin, penicillin/novobiocin, quinupristin/dalfopristin, clindamycin, rifampin, ciprofloxacin, trimethprim/sulfamethoxazol, vancomycin, and linezolid. Over 66% of the S. aureus isolates were resistant to penicillin. Resistance was also seen for gentamicin (11.9%), erythromycin (7.7%), methicillin (oxacillin and cefoxitin, 6.2%), and tetracycline (4.2%). No noticeable change was observed in penicillin, gentamicin, and erythromycin resistance over the 7-year period. Tetracycline resistance appeared to decrease consistently, whereas methicillin resistance was observed from 2005. About 2.7% (11/402) were resistant to three or more antimicrobials. Genotyping of the 17 methicillin-resistant S. aureus (MRSA) isolated from each cow revealed two staphylococcal cassette chromosome mec (SCCmec) types (IV and IVa), three spa types (t286, t324, and untypable), and two sequence types (ST1 and ST72). Eleven of 17 (64.7%) MRSA strains belonged to SCCmec IVa-t324-ST72. The rest of strains belonged to SCCmec IVa-t286-ST1 (n = 3) and SCCmec IV-untypable-ST72 (n = 3). None of the MRSA carried the Panton-Valentine leukocidin gene. These characteristics are the same as those found in community-acquired (CA) MRSA strains prevalent in humans in Korea. Three pulsed-field gel electrophoresis types (A-C) were observed among the 17 MRSA strains examined, and 14 strains belonged to the same pulsed-field gel electrophoresis pattern regardless of their geographical origin and year of isolation. The results of this study provide evidence of CA-MRSA infection in dairy cattle for the first time in Korea. PMID:21034263

  4. Heavy metals in liquid pig manure in light of bacterial antimicrobial resistance

    International Nuclear Information System (INIS)

    Heavy metals are regularly found in liquid pig manure, and might interact with bacterial antimicrobial resistance. Concentrations of heavy metals were determined by atomic spectroscopic methods in 305 pig manure samples and were connected to the phenotypic resistance of Escherichia coli (n=613) against 29 antimicrobial drugs. Concentrations of heavy metals (/kg dry matter) were 0.08–5.30 mg cadmium, 1.1–32.0 mg chrome, 22.4–3387.6 mg copper, <2.0–26.7 mg lead, <0.01–0.11 mg mercury, 3.1–97.3 mg nickel and 93.0–8239.0 mg zinc. Associated with the detection of copper and zinc, resistance rates against β-lactams were significantly elevated. By contrast, the presence of mercury was significantly associated with low antimicrobial resistance rates of Escherichia coli against β-lactams, aminoglycosides and other antibiotics. Effects of subinhibitory concentrations of mercury on bacterial resistance against penicillins, cephalosporins, aminoglycosides and doxycycline were also demonstrated in a laboratory trial. Antimicrobial resistance in the porcine microflora might be increased by copper and zinc. By contrast, the occurrence of mercury in the environment might, due to co-toxicity, act counter-selective against antimicrobial resistant strains.

  5. Heavy metals in liquid pig manure in light of bacterial antimicrobial resistance

    Energy Technology Data Exchange (ETDEWEB)

    Hoelzel, Christina S., E-mail: Christina.Hoelzel@wzw.tum.de [Chair of Animal Hygiene, Technische Universitaet Muenchen, Weihenstephaner Berg 3, 85354 Freising (Germany); Mueller, Christa [Institute for Agroecology, Organic Farming and Soil Protection, Bavarian State Research Center for Agriculture (LfL), Lange Point 12, 85354 Freising (Germany); Harms, Katrin S. [Chair of Animal Hygiene, Technische Universitaet Muenchen, Weihenstephaner Berg 3, 85354 Freising (Germany); Mikolajewski, Sabine [Department for Quality Assurance and Analytics, Bavarian State Research Center for Agriculture (LfL), Lange Point 4, 85354 Freising (Germany); Schaefer, Stefanie; Schwaiger, Karin; Bauer, Johann [Chair of Animal Hygiene, Technische Universitaet Muenchen, Weihenstephaner Berg 3, 85354 Freising (Germany)

    2012-02-15

    Heavy metals are regularly found in liquid pig manure, and might interact with bacterial antimicrobial resistance. Concentrations of heavy metals were determined by atomic spectroscopic methods in 305 pig manure samples and were connected to the phenotypic resistance of Escherichia coli (n=613) against 29 antimicrobial drugs. Concentrations of heavy metals (/kg dry matter) were 0.08-5.30 mg cadmium, 1.1-32.0 mg chrome, 22.4-3387.6 mg copper, <2.0-26.7 mg lead, <0.01-0.11 mg mercury, 3.1-97.3 mg nickel and 93.0-8239.0 mg zinc. Associated with the detection of copper and zinc, resistance rates against {beta}-lactams were significantly elevated. By contrast, the presence of mercury was significantly associated with low antimicrobial resistance rates of Escherichia coli against {beta}-lactams, aminoglycosides and other antibiotics. Effects of subinhibitory concentrations of mercury on bacterial resistance against penicillins, cephalosporins, aminoglycosides and doxycycline were also demonstrated in a laboratory trial. Antimicrobial resistance in the porcine microflora might be increased by copper and zinc. By contrast, the occurrence of mercury in the environment might, due to co-toxicity, act counter-selective against antimicrobial resistant strains.

  6. Australian Group on Antimicrobial Resistance Enterococcus Surveillance Programme annual report, 2010.

    Science.gov (United States)

    Coombs, Geoffrey W; Pearson, Julie C; Christiansen, Keryn; Gottlieb, Thomas; Bell, Jan M; George, Narelle; Turnidge, John D

    2013-09-01

    In 2010, 15 institutions around Australia conducted a period prevalence study of key resistances in isolates of Enterococcus species associated with a range of clinical disease amongst in- and outpatients. Each institution collected up to 100 consecutive isolates and tested these for susceptibility to commonly used antimicrobials using standardised methods. Vancomycin-resistant Enterococcus faecium and Enterococcus faecalis were characterised by pulsed-field gel electrophoresis. Multilocus sequence typing was performed on representative pulsotypes of E. faecium. Susceptibility results were compared with similar surveys conducted in 1995, 1999, 2003, 2005, 2007 and 2009. In the 2010 survey, E. faecalis (1,201 isolates) and E. faecium (170 isolates) made up 98.9% of the 1,386 isolates tested. Ampicillin resistance was very common (85.3%) in E. faecium and absent in E. faecalis. Non-susceptibility to vancomycin was 36.5% in E. faecium (similar to the 35.2% in 2009 but up from 15.4% in the 2007 survey) and 0.5% in E. faecalis. There were significant differences in the proportion of vancomycin-resistant E. faecium between the states ranging from 0% in Western Australia to 54.4% in South Australia. The vanB gene was detected in 62 E. faecium and 3 E. faecalis isolates. The vanA gene was detected in 1 E. faecium isolate. All vancomycin-resistant E. faecium belonged to clonal complex 17. The most common sequence type (ST) was ST203, which was found in all regions that had reports of vancomycin resistant enterococci. ST341 was detected only in New South Wales/Australian Capital Territory and ST414 only in South Australia and Victoria. High-level resistance to gentamicin was 34.1% in E. faecalis and 66.1% in E. faecium. A subset of isolates was tested against high-level streptomycin, linezolid and quinupristin/dalfopristin. High-level streptomycin resistance was found in 8.2% of E. faecalis isolates and 43.8% of E. faecium isolates. Linezolid non

  7. Synergistic antimicrobial activity of Camellia sinensis and Juglans regia against multidrug-resistant bacteria.

    Science.gov (United States)

    Farooqui, Amber; Khan, Adnan; Borghetto, Ilaria; Kazmi, Shahana U; Rubino, Salvatore; Paglietti, Bianca

    2015-01-01

    Synergistic combinations of antimicrobial agents with different mechanisms of action have been introduced as more successful strategies to combat infections involving multidrug resistant (MDR) bacteria. In this study, we investigated synergistic antimicrobial activity of Camellia sinensis and Juglans regia which are commonly used plants with different antimicrobial agents. Antimicrobial susceptibility of 350 Gram-positive and Gram-negative strains belonging to 10 different bacterial species, was tested against Camellia sinensis and Juglans regia extracts. Minimum inhibitory concentrations (MICs) were determined by agar dilution and microbroth dilution assays. Plant extracts were tested for synergistic antimicrobial activity with different antimicrobial agents by checkerboard titration, Etest/agar incorporation assays, and time kill kinetics. Extract treated and untreated bacteria were subjected to transmission electron microscopy to see the effect on bacterial cell morphology. Camellia sinensis extract showed higher antibacterial activity against MDR S. Typhi, alone and in combination with nalidixic acid, than to susceptible isolates." We further explore anti-staphylococcal activity of Juglans regia that lead to the changes in bacterial cell morphology indicating the cell wall of Gram-positive bacteria as possible target of action. The synergistic combination of Juglans regia and oxacillin reverted oxacillin resistance of methicillin resistant Staphylococcus aureus (MRSA) strains in vitro. This study provides novel information about antimicrobial and synergistic activity of Camellia sinensis and Juglans regia against MDR pathogens.

  8. Synergistic antimicrobial activity of Camellia sinensis and Juglans regia against multidrug-resistant bacteria.

    Directory of Open Access Journals (Sweden)

    Amber Farooqui

    Full Text Available Synergistic combinations of antimicrobial agents with different mechanisms of action have been introduced as more successful strategies to combat infections involving multidrug resistant (MDR bacteria. In this study, we investigated synergistic antimicrobial activity of Camellia sinensis and Juglans regia which are commonly used plants with different antimicrobial agents. Antimicrobial susceptibility of 350 Gram-positive and Gram-negative strains belonging to 10 different bacterial species, was tested against Camellia sinensis and Juglans regia extracts. Minimum inhibitory concentrations (MICs were determined by agar dilution and microbroth dilution assays. Plant extracts were tested for synergistic antimicrobial activity with different antimicrobial agents by checkerboard titration, Etest/agar incorporation assays, and time kill kinetics. Extract treated and untreated bacteria were subjected to transmission electron microscopy to see the effect on bacterial cell morphology. Camellia sinensis extract showed higher antibacterial activity against MDR S. Typhi, alone and in combination with nalidixic acid, than to susceptible isolates." We further explore anti-staphylococcal activity of Juglans regia that lead to the changes in bacterial cell morphology indicating the cell wall of Gram-positive bacteria as possible target of action. The synergistic combination of Juglans regia and oxacillin reverted oxacillin resistance of methicillin resistant Staphylococcus aureus (MRSA strains in vitro. This study provides novel information about antimicrobial and synergistic activity of Camellia sinensis and Juglans regia against MDR pathogens.

  9. Synergistic antimicrobial activity of Camellia sinensis and Juglans regia against multidrug-resistant bacteria.

    Science.gov (United States)

    Farooqui, Amber; Khan, Adnan; Borghetto, Ilaria; Kazmi, Shahana U; Rubino, Salvatore; Paglietti, Bianca

    2015-01-01

    Synergistic combinations of antimicrobial agents with different mechanisms of action have been introduced as more successful strategies to combat infections involving multidrug resistant (MDR) bacteria. In this study, we investigated synergistic antimicrobial activity of Camellia sinensis and Juglans regia which are commonly used plants with different antimicrobial agents. Antimicrobial susceptibility of 350 Gram-positive and Gram-negative strains belonging to 10 different bacterial species, was tested against Camellia sinensis and Juglans regia extracts. Minimum inhibitory concentrations (MICs) were determined by agar dilution and microbroth dilution assays. Plant extracts were tested for synergistic antimicrobial activity with different antimicrobial agents by checkerboard titration, Etest/agar incorporation assays, and time kill kinetics. Extract treated and untreated bacteria were subjected to transmission electron microscopy to see the effect on bacterial cell morphology. Camellia sinensis extract showed higher antibacterial activity against MDR S. Typhi, alone and in combination with nalidixic acid, than to susceptible isolates." We further explore anti-staphylococcal activity of Juglans regia that lead to the changes in bacterial cell morphology indicating the cell wall of Gram-positive bacteria as possible target of action. The synergistic combination of Juglans regia and oxacillin reverted oxacillin resistance of methicillin resistant Staphylococcus aureus (MRSA) strains in vitro. This study provides novel information about antimicrobial and synergistic activity of Camellia sinensis and Juglans regia against MDR pathogens. PMID:25719410

  10. Transgenic Cotton and Disease Resistance Genes

    Institute of Scientific and Technical Information of China (English)

    RAJASEKARAN; Kanniah

    2008-01-01

    Success in conventional breeding for resistance to mycotoxin-producing or other phytopathogenic fungi is dependent on the availability of resistance gene(s) in the germplasm.Even when it is available,breeding for disease-resistant crops is very time consuming,especially in perennial crops such as

  11. Virulence Genes, Genetic Diversity, Antimicrobial Susceptibility and Phylogenetic Background of Escherichia coli Isolates

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    Abdi

    2015-08-01

    Full Text Available Background The epidemiology of Uropathogenic Escherichia coli (UPEC in urban and rural communities in Iran was never investigated prior to this study. Objectives The aims of this study were to detect the frequency of virulence genes and determine the antimicrobial susceptibility and phylogenetic background of Escherichia coli isolates collected from urban and rural communities. Materials and Methods A total of 100 E. coli isolates were collected from urine samples of patients with urinary tract infections (UTIs residing in two different locations, and confirmed by current biochemical tests. The phylogenetic groups were determined by the triplex-polymerase chain reaction (PCR method, and multiplex PCRs were used to detect eight Vf genes (fimH, iucD, irp2, hlyA, ompT, iha, iroN, and cnf1. The susceptibility profile of E. coli isolates was determined by the disk diffusion method. Results Ninety-five percent of UPEC showed at least one of the virulence genes, the most prevalent being fimH (95%, followed by irp2 (89%, iucD (69%, ompT (67%, iroN (29%, and iha (29%. The various combinations of detected genes were designated as virulence patterns. Phylogenetic groups, B2 (55% and D (22%, comprised the majority of isolated strains. Phenotypic tests showed that 92%, 74% and 71% of the isolates were resistant to ampicillin, ceftizoxime and cefixime, respectively. Conclusions These findings indicate that the UPEC isolates had eight virulence factors with high frequencies. Moreover, these results suggest a direct connection between virulence factors, gene diversity, phylogenetic background, and antimicrobial resistance in UPEC isolates.

  12. Research of macrolide resistant phenotype and resistant gene and antimicrobial susceptibility in streptococcus pneumonia isolated from children in Yueqing%乐清地区儿童肺炎链球菌耐药性及大环内酯类耐药表型和耐药基因型

    Institute of Scientific and Technical Information of China (English)

    林雪峰; 朱旭阳; 江丹英; 王兵勇; 陈静

    2015-01-01

    Objective To investigate the distribution of macrolide resistant phenotype and resistant gene, and antimicro-bial susceptibility in streptococcus pneumonia isolated from children in Yueqing. Methods A total of 124 streptococcus pneumonia isolates from children in Yueqing was analyzed for detecting minimal inhibitory concentration. Then the macrolide resistance phenotypes were identified by double disc test with erythromycin and clindamycin discs. The ermB and mefE genes were amplified by PCR. Results In 124 strains of streptococcus pneumonia, the resistance rates to ery-thromycin, clindamycin, tetracycline, and sulfamethoxazole were 96.77%, 93.55%, 84.68%and 81.45%respectively. The resistance rate to penicillin, chloromycetin and levofloxacin were lower which were 20.16%, 5.65%and 0.81%respectively. No strain was found that resistant to amoxicillin and vancomycin. Majority(96.67%) of 120 streptococcus pneumonia strains of macrolide were cMLS phenotype. One (0.83%) strain showed iMLS phenotype and 3 (2.5%) strains belonged to macrolide resistance phenotype. The ermB gene was identified in 97.50%and mefE gene was 6.67%. Conclusion The re-sistance of streptococcus pneumonia to macrolide is serious in children from Yueqing. The ermB-mediated cMLS is the most prevalent phenotype among macrolide resistance streptococcus pneumonia isolates. Obviously, the macrolide antibiotic is not effective on streptococcus pneumonia infection.%目的:了解乐清地区儿童患者分离的肺炎链球菌耐药性及大环内酯类耐药表型和耐药基因型分布情况。方法对2014年乐清地区儿童患者分离的124株肺炎链球菌采用细菌鉴定分析仪进行9种抗菌药物的最低抑菌浓度(MIC)检测,同时对大环内酯类耐药肺炎链球菌用红霉素和克林霉素双纸片协同试验确定其耐药表型,用聚合酶链反应(PCR)扩增这些菌株的耐药基因ermB和mefE。结果124株肺炎链球菌中,红霉素、克林霉素、四

  13. Plant-derived antimicrobial agents and their synergistic interaction against drug-sensitive and -resistant pathogens

    OpenAIRE

    Mulyaningsih, Sri

    2010-01-01

    Resistance toward antibiotics has become a problem on a global scale. Methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecalis (VRE) are a major cause of morbidity and mortality in hospitalized patients. To overcome resistance, many antimicrobial agents have been investigated and Traditional Chinese Medicinal (TCM) plants were also examined as source of alternative agents. Eucalyptus globulus Labill (Myrtaceae) was the most active plant among the 84 T...

  14. MLST typing of antimicrobial-resistant Propionibacterium acnes isolates from patients with moderate to severe acne vulgaris.

    Science.gov (United States)

    Giannopoulos, Lambros; Papaparaskevas, Joseph; Refene, Eirini; Daikos, Georgios; Stavrianeas, Nikolaos; Tsakris, Athanassios

    2015-02-01

    Molecular typing data on antimicrobial-resistant Propionibacterium strains are limited in the literature. We examined antimicrobial resistance profiles and the underlying resistance mechanisms in Propionibacterium spp. isolates recovered from patients with moderate to severe acne vulgaris in Greece. The clonallity of the resistant Propionibacterium acnes isolates was also investigated. Propionibacterium spp. isolates were detected using Tryptone-Yeast Extract-Glucose (TYG) agar plates supplemented with 4% furazolidone. Erythromycin, clindamycin, vancomycin, penicillin, co-trimoxazole, doxycycline, minocycline and ciprofloxacin MICs were determined using the gradient strip method. Erythromycin, clindamycin and tetracycline mechanisms of resistance were determined using PCR and sequencing of the domain V of 23S rRNA and 16S rRNA, as well as the presence of the ermX gene. Typing was performed using the multi locus sequence typing (MLST) methodology. Seventy nine isolates from 76 patients were collected. Twenty-three isolates (29.1%) exhibited resistance to erythromycin and clindamycin, while two additional isolates (2.5%) were resistant only to erythromycin. Resistance to tetracycline was not detected. The underlying molecular mechanisms were point mutations A2059G and A2058G. MLST typing of the P. acnes resistant isolates revealed that lineage type IA1 (ST-1, 3 and 52) prevailed (12/18; 66.7%), whilst lineage type IA2 (ST-2 and 22) accounted for five more isolates (27.8%). Susceptible isolates were more evenly distributed between ST types. Propionibacterium spp. from moderate to severe acne vulgaris in Greece are frequently resistant to erythromycin/clindamycin but not to tetracyclines, mainly due to the point mutations A2059G and A2058G. P. acnes resistant isolates were more clonally related than susceptible ones and belonged to a limited number of MLST types.

  15. Antimicrobial Resistance and Virulence Factors of Escherichia coli in Cheese Made from Unpasteurized Milk in Three Cities in Brazil.

    Science.gov (United States)

    Ribeiro, Laryssa Freitas; Barbosa, Mayhara Martins Cordeiro; Pinto, Fernanda de Rezende; Maluta, Renato Pariz; Oliveira, Mônica Costa; de Souza, Viviane; de Medeiros, Maria Izabel Merino; Borges, Lucimara Antonio; do Amaral, Luiz Augusto; Fairbrother, John Morris

    2016-09-01

    The production of cheeses from unpasteurized milk is still widespread in Brazil, even with a legal ban imposed on its marketing. The manufacture of this cheese is a public health problem, due to the use of raw milk and the poor hygienic conditions throughout the supply chain process. Contamination may occur from several sources and involve several different pathogenic microorganisms, such as Escherichia coli. The latter can cause different clinical manifestations depending on the pathotype involved. Furthermore, some isolates manifest antimicrobial resistance and may be a risk for public health. The purpose of the current study was to investigate the presence of potentially pathogenic E. coli in raw-milk cheese in Brazil and their possible risk to public health. A total of 83 cheeses were collected from three different cities and 169 E. coli isolates were characterized for the presence of enteropathogenic E. coli, Shigatoxigenic E. coli, enterotoxigenic E. coli, extraintestinal pathogenic E. coli (ExPEC) virulence genes, phylogenetic type, antimicrobial resistance, O serogroup, and pulsed-field gel electrophoresis. The number of samples positive for E. coli was highest in Aracaju (90.32%, 28/31). The prevalence of samples positive for potential ExPEC genes was similar for Uberaba and Aracaju (23.07%); the most prevalent ExPEC virulence genes were tsh, iucD, and papC. Isolates from Uberaba had a higher prevalence of resistance to tetracycline (38.46%), amoxicillin/clavulanic acid (58.85%), and ampicillin (61.54%) than the other cities. Overall, antimicrobial resistance genes tetB, blaTEM, and blaCMY-2 were the most prevalent genes (26.32%, 15.79%, and 28.95%, respectively) and the most prevalent serotypes were O4 (8%), 018 (12%), and O23 (8%). Clones originating from the same regions and from different regions were observed. These results emphasize the presence of a potential danger for humans in the consumption of raw-milk cheeses in three cities in Brazil due to

  16. Antimicrobial resistance programs in canada 1995-2010: a critical evaluation

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    Conly John M

    2012-02-01

    Full Text Available Abstract Background In Canada, systematic efforts for controlling antibiotic resistance began in 1997 following a national Consensus Conference. The Canadian strategy produced 27 recommendations, one of which was the formation of the Canadian Committee on Antibiotic Resistance (CCAR. In addition several other organizations began working on a national or provincial basis over the ensuing years on one or more of the 3 identified core areas of the strategy. Critical evaluation of the major programs within Canada which focused on antimicrobial resistance and the identified core components has not been previously conducted. Findings Data was collected from multiple sources to determine the components of four major AMR programs that were considered national based on their scope or in the delivery of their mandates. Assessment of program components was adapted from the report from the International Forum on Antibiotic Resistance colloquium. Most of the programs used similar tools but only the Do Bugs Need Drugs Program (DBND had components directed towards day cares and schools. Surveillance programs for antimicrobial resistant pathogens have limitations and/or significant sources of bias. Overall, there has been a 25.3% decrease in oral antimicrobial prescriptions in Canada since 1995, mainly due to decreases in β lactams, sulphonamides and tetracyclines in temporal association with multiple programs with the most comprehensive and sustained national programs being CCAR and DBND. Conclusions Although there has been a substantial decrease in oral antimicrobial prescriptions in Canada since 1995, there remains a lack of leadership and co-ordination of antimicrobial resistance activities.

  17. Antimicrobial resistance in eight US hospitals along the US-Mexico border, 2000-2006.

    Science.gov (United States)

    Benoit, S R; Ellingson, K D; Waterman, S H; Pearson, M L

    2014-11-01

    Antimicrobial resistance (AR) is a growing problem worldwide and international travel, cross-border migration, and antimicrobial use may contribute to the introduction or emergence of AR. We examined AR rates and trends along the US-Mexico border by analysing microbiology data from eight US hospitals in three states bordering Mexico. Microbiology data were ascertained for the years 2000-2006 and for select healthcare and community pathogens including, three Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae) and three Gram-positive (Staphylococcus aureus, Enterococcus, Streptococcus pneumoniae) pathogens and 10 antimicrobial-pathogen combinations. Resistance was highest in S. aureus (oxacillin resistance 45·7%), P. aeruginosa (quinolone resistance 22·3%), and E. coli (quinolone resistance 15·6%); six (60%) of the 10 antimicrobial-pathogen combinations studied had a significantly increasing trend in resistance over the study period. Potential contributing factors in the hospital and community such as infection control practices and antimicrobial use (prescription and non-prescription) should be explored further in the US-Mexico border region.

  18. Analysis on Antimicrobial Resistance of Clinical Bacteria Isolated from County Hospitals and a Teaching Hospital

    Institute of Scientific and Technical Information of China (English)

    SUN Ziyong; LI Li; ZHU Xuhui; MA Yue; LI Jingyun; SHEN Zhengyi; JIN Shaohong

    2006-01-01

    The distinction of antimicrobial resistance of clinical bacteria isolated from county hospitals and a teaching hospital was investigated. Disc diffusion test was used to study the antimicrobial resistance of isolates collected from county hospitals and a teaching hospital. The data was analyzed by WHONET5 and SPSS statistic software. A total of 655 strains and 1682 strains were collected from county hospitals and a teaching hospital, respectively, in the year of 2003. The top ten pathogens were Coagulase negative staphylococci (CNS), E. coli, Klebsiella spp. , S. areus, P. aeruginosa, Enterococcus spp. , Enterobacter spp. , otherwise Salmonella spp. , Proteus spp. , Shigella spp. in county hospitals and Streptococcus spp. , Acinetobacter spp. , X. maltophilia in the teaching hospital. The prevalence of multi-drug resistant bacteria was 5% (4/86) of methicillin-resistant S. areus (MRSA), 12% (16/133) and 15.8 % (9/57) of extended-spectrum β-lactamases producing strains of E. coli and Klebsiella spp. , respectively, in county hospitals. All of the three rates were lower than that in the teaching hospital and the difference was statistically significant (P<0.01). However, the incidence of methicillin-resistant CNS (MRCNS) reached to 70 % (109/156) in the two classes of hospitals. Generally, the antimicrobial resistant rates in the county hospitals were lower than those in the teaching hospital, except the resistant rates of ciprofloxacin, erythromycin, clindamycin, SMZco which were similar in the two classes of hospitals. There were differences between county hospitals and the teaching hospital in the distribution of clinical isolates and prevalence of antimicrobial resistance. It was the basis of rational use of antimicrobial agents to monitor antimicrobial resistance by each hospital.

  19. ANTIMICROBIAL DRUG RESISTANCE IN STRAINS OF Escherichia coli ISOLATED FROM FOOD SOURCES

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    Mohammed Uddin Rasheed

    2014-07-01

    Full Text Available A variety of foods and environmental sources harbor bacteria that are resistant to one or more antimicrobial drugs used in medicine and agriculture. Antibiotic resistance in Escherichia coli is of particular concern because it is the most common Gram-negative pathogen in humans. Hence this study was conducted to determine the antibiotic sensitivity pattern of E. coli isolated from different types of food items collected randomly from twelve localities of Hyderabad, India. A total of 150 samples comprising; vegetable salad, raw egg-surface, raw chicken, unpasteurized milk, and raw meat were processed microbiologically to isolate E. coli and to study their antibiotic susceptibility pattern by the Kirby-Bauer method. The highest percentages of drug resistance in isolates of E. coli were detected from raw chicken (23.3% followed by vegetable salad (20%, raw meat (13.3%, raw egg-surface (10% and unpasteurized milk (6.7%. The overall incidence of drug resistant E. coli was 14.7%. A total of six (4% Extended Spectrum β-Lactamase (ESBL producers were detected, two each from vegetable salads and raw chicken, and one each from raw egg-surface and raw meat. Multidrug resistant strains of E. coli are a matter of concern as resistance genes are easily transferable to other strains. Pathogen cycling through food is very common and might pose a potential health risk to the consumer. Therefore, in order to avoid this, good hygienic practices are necessary in the abattoirs to prevent contamination of cattle and poultry products with intestinal content as well as forbidding the use of untreated sewage in irrigating vegetables.

  20. Identification of aminoglycoside resistance genes by Triplex PCR in Enterococcus spp. isolated from ICUs.

    Science.gov (United States)

    Mirnejad, Reza; Sajjadi, Nikta; Masoumi Zavaryani, Sara; Piranfar, Vahhab; Hajihosseini, Maryam; Roshanfekr, Maliheh

    2016-09-01

    Early detection of antibiotic-resistant enterococci is an important part of patient treatment. Therefore, the aim of the present study was to evaluate the resistance patterns and simultaneously identify and characterise the resistance genes in Enterococcus spp. using a triplex polymerase chain reaction (PCR) method. In all, 150 consecutive Enterococcus spp were collected from several hospitals in Tehran (Iran) from January to December 2015. The Enterococcus species were identified by standard phenotypic/biochemical tests and PCR. The antimicrobial resistance patterns were determined using a disk diffusion method. The triplex PCR method was designed to identify gentamicin and other aminoglycoside resistance genes. Among the 150 Enterococcus specimens, 87 cases (58%) were Enterococcus faecalis, and 63 cases (42%) were Enterococcus faecium. The highest frequency of resistance was observed for tetracycline while the lowest was found for vancomycin. Among the identified samples, 56.9% contained the aac(6')-Ie-aph(2'')-Ia gene, 22.2% contained the aph(3')-IIIa gene, and 38.8% contained the ant(4')-?a gene. Eight percent of the isolates contained the three aminoglycoside resistance genes. Data analysis showed that there was a significant correlation between the phenotypic gentamicin resistance and the presence of the aminoglycoside resistance genes (18.9%, p Enterococcus strains had increased aminoglycoside resistance. The direct correlation between resistance genes, such as the aminoglycoside resistance factor, and phenotypic resistance was not significant (p > 0.05).

  1. The impact of an antimicrobial stewardship programme on the use of antimicrobials and the evolution of drug resistance.

    Science.gov (United States)

    Del Arco, A; Tortajada, B; de la Torre, J; Olalla, J; Prada, J L; Fernández, F; Rivas, F; García-Alegría, J; Faus, V; Montiel, N

    2015-02-01

    Misuse of antibiotics can provoke increased bacterial resistance. There are no immediate prospects of any new broad-spectrum antibiotics, especially any with activity against enterobacteria, coming onto the market. Therefore, programmes should be implemented to optimise antimicrobial therapy. In a quasi-experimental study, the results for the pre-intervention year were compared with those for the 3 years following the application of an antimicrobial stewardship programme. We describe 862 interventions carried out as part of the stewardship programme at the Hospital Costa del Sol from 2009 to 2011. We examined the compliance of the empirical antimicrobial treatment with the programme recommendations and the treatment optimisation achieved by reducing the antibiotic spectrum and adjusting the dose, dosing interval and duration of treatment. In addition, we analysed the evolution of the sensitivity profile of the principal microorganisms and the financial savings achieved. 93 % of the treatment recommendations were accepted. The treatment actions taken were to corroborate the empirical treatment (46 % in 2009 and 31 % in 2011) and to reduce the antimicrobial spectrum taking into account the antibiogram results (37 % in 2009 and 58 % in 2011). The main drugs assessed were imipenem/meropenem, used in 38.6 % of the cases, and cefepime (20.1 %). The sensitivity profile of imipenem against Pseudomonas aeruginosa increased by 10 % in 2011. Savings in annual drug spending (direct costs) of 30,000 Euros were obtained. Stewardship programmes are useful tools for optimising antimicrobial therapy. They may contribute to preventing increased bacterial resistance and to reducing the long-term financial cost of antibiotic treatment.

  2. [Antimicrobial activities of ant Ponericin W1 against plant pathogens in vitro and the disease resistance in its transgenic Arabidopsis].

    Science.gov (United States)

    Chen, Yong-Fang; Sun, Peng-Wei; Tang, Ding-Zhong

    2013-08-01

    The antimicrobial peptides (AMPs) exhibit a broad antimicrobial spectrum. The application of AMPs from non-plant organisms attracts considerable attention in plant disease resistance engineering. Ponericin W1, isolated from the venom of ant (Pachycondyla goeldii), shows antimicrobial activities against Gram-positive bacteria, Gram-negative bacteria and the budding yeast (Saccharomyces cerevisiae); however, it is not clear whether Ponericin W1 is effective against plant pathogens. The results of this study indicated synthesized Ponericin W1 inhibited mycelial growth of Magnaporthe oryzae and Botrytis cinerea, as well as hyphal growth and spore production of Fusarium graminearum. Besides, Ponericin W1 exhibited antibacterial activities against Pseudomonas syringae pv. tomato and Xanthomonas oryzae pv. oryzae. After codon optimization, Ponericin W1 gene was constructed into plant expression vector, and transformed into Arabidopsis thaliana by floral dip method. The Ponericin W1 was located in intercellular space of the transgenic plants as expected. Compared with the wild-type plants, there were ungerminated spores and less hyphal, conidia on the leaves of transgenic plants after innoculation with the powdery mildew fungus Golovinomyces cichoracearum. After innoculation with the pathogenic bac-terium Pseudomonas syringae pv. tomato, the baceria in the leaves of transgenic plants was significantly less than the wild-type plants, indicating that the transgenic plants displayed enhanced disease resistance to pathogens. These results demonstrate a potential use of Ponericin W1 in genetic engineering for broad-spectrum plant disease resistance. PMID:23956091

  3. Caracterização fenotípica da resistência a antimicrobianos e detecção do gene mecA em Staphylococcus spp. coagulase-negativos isolados de amostras animais e humanas Phenotypic characterization of antimicrobial resistance and detection of the mecA gene in coagulase-negative Staphylococcus spp. isolates from animal and human samples

    Directory of Open Access Journals (Sweden)

    Lidiane de Castro Soares

    2008-08-01

    Full Text Available Os estafilococos coagulase-negativos (ECN fazem parte da microbiota normal da pele e, apesar de terem sido considerados saprófitas por muito tempo, o seu significado clínico como agente etiológico tem aumentado com o passar dos anos. Neste estudo, foram obtidos 72 isolados de ECN a partir de amostras do conduto auditivo de cães, de mastite bovina e de infecções humanas. Staphylococcus xylosus foi o microrganismo mais isolado, nas amostras animais, e S. cohnii subsp. cohnii em humanos. Os isolados foram avaliados de modo a traçar o perfil fenotípico de sua resistência aos antimicrobianos mais indicados no tratamento de infecções estafilocócicas. Foi detectado um elevado nível de resistência à penicilina e ampicilina. A gentamicina, a vancomicina e a associação ampicilina+sulbactam foram eficientes frente aos isolados testados. A resistência à oxacilina foi avaliada por meio dos testes de difusão em disco modificada, ágar screen, microdiluição em caldo e diluição em ágar para constatar, se à semelhança do que ocorre com os estafilococos coagulase-positivo, esta pode ser mediada pelo gene mecA e apresentada de forma heterogênea. A presença do gene mecA foi determinada pelo método da Reação em Cadeia de Polimerase (PCR, sendo 5,6% dos isolados mecA positivos.Coagulase-negative staphylococci (SCN make part of the normal microbiota skin and although they have been considered saprophytics for years, nowadays their clinical significance as an etiologic agent has increased. In this study, 72 SCN isolates obtained from external ear canals of dogs, bovine mastitis and human nosocomial infections were evaluated. Staphylococcus xylosus was the most prevalent microorganism in animal samples and S. cohnii subsp. cohnii in human samples. SCN isolates were evaluated in order to establish a phenotypical resistance pattern towards the most indicated antibiotics for staphyloccocal infections. A high level of resistance to penicillin

  4. The MisR Response Regulator Is Necessary for Intrinsic Cationic Antimicrobial Peptide and Aminoglycoside Resistance in Neisseria gonorrhoeae.

    Science.gov (United States)

    Kandler, Justin L; Holley, Concerta L; Reimche, Jennifer L; Dhulipala, Vijaya; Balthazar, Jacqueline T; Muszyński, Artur; Carlson, Russell W; Shafer, William M

    2016-08-01

    During infection, the sexually transmitted pathogen Neisseria gonorrhoeae (the gonococcus) encounters numerous host-derived antimicrobials, including cationic antimicrobial peptides (CAMPs) produced by epithelial and phagocytic cells. CAMPs have both direct and indirect killing mechanisms and help link the innate and adaptive immune responses during infection. Gonococcal CAMP resistance is likely important for avoidance of host nonoxidative killing systems expressed by polymorphonuclear granulocytes (e.g., neutrophils) and intracellular survival. Previously studied gonococcal CAMP resistance mechanisms include modification of lipid A with phosphoethanolamine by LptA and export of CAMPs by the MtrCDE efflux pump. In the related pathogen Neisseria meningitidis, a two-component regulatory system (2CRS) termed MisR-MisS has been shown to contribute to the capacity of the meningococcus to resist CAMP killing. We report that the gonococcal MisR response regulator but not the MisS sensor kinase is involved in constitutive and inducible CAMP resistance and is also required for intrinsic low-level resistance to aminoglycosides. The 4- to 8-fold increased susceptibility of misR-deficient gonococci to CAMPs and aminoglycosides was independent of phosphoethanolamine decoration of lipid A and the levels of the MtrCDE efflux pump and seemed to correlate with a general increase in membrane permeability. Transcriptional profiling and biochemical studies confirmed that expression of lptA and mtrCDE was not impacted by the loss of MisR. However, several genes encoding proteins involved in membrane integrity and redox control gave evidence of being MisR regulated. We propose that MisR modulates the levels of gonococcal susceptibility to antimicrobials by influencing the expression of genes involved in determining membrane integrity. PMID:27216061

  5. Multistrain models predict sequential multidrug treatment strategies to result in less antimicrobial resistance than combination treatment

    DEFF Research Database (Denmark)

    Ahmad, Amais; Zachariasen, Camilla; Christiansen, Lasse Engbo;

    2016-01-01

    Background: Combination treatment is increasingly used to fight infections caused by bacteria resistant to two or more antimicrobials. While multiple studies have evaluated treatment strategies to minimize the emergence of resistant strains for single antimicrobial treatment, fewer studies have...... generated by a mathematical model of the competitive growth of multiple strains of Escherichia coli.Results: Simulation studies showed that sequential use of tetracycline and ampicillin reduced the level of double resistance, when compared to the combination treatment. The effect of the cycling frequency...... frequency did not play a role in suppressing the growth of resistant strains, but the specific order of the two antimicrobials did. Predictions made from the study could be used to redesign multidrug treatment strategies not only for intramuscular treatment in pigs, but also for other dosing routes....

  6. The effects of tertiary wastewater treatment on the prevalence of antimicrobial resistant bacteria

    DEFF Research Database (Denmark)

    Guardabassi, L.; Wong, Danilo Lo Fo; Dalsgaard, A.

    2002-01-01

    The effects of tertiary wastewater treatment on the prevalence of antimicrobial resistant bacteria were investigated in two large-scale municipal treatment plants during a period of six months. Total and relative numbers of resistant bacteria were determined in raw sewage, treated sewage and anae...

  7. Patterns of antimicrobial resistance in pathogenic Escherichia coli isolates from cases of calf enteritis during the spring-calving season.

    Science.gov (United States)

    Gibbons, James F; Boland, Fiona; Buckley, James F; Butler, Francis; Egan, John; Fanning, Séamus; Markey, Bryan K; Leonard, Finola C

    2014-05-14

    Neonatal enteritis is a common condition of young calves and can be caused by pathogenic strains of Escherichia coli. We hypothesised that on-farm antimicrobial use would result in an increased frequency of resistance in these strains during the calving season. We also sought to determine if the frequency of resistance reflected on-farm antimicrobial use. Faecal samples were collected from cases of calf enteritis on 14 spring-calving dairy farms during two 3 week periods: Period 1 - February 11th through March 2nd 2008 and Period 2 - April 14th through May 5th 2008. E. coli were cultured from these samples, pathogenic strains were identified and antimicrobial susceptibility testing was carried out on these pathogenic isolates. Antimicrobial prescribing data were collected from each farm for the previous 12 months as an indicator of antimicrobial use. The correlation between antimicrobial use and resistance was assessed using Spearman's correlation coefficient. Logistic regression analysis was used to investigate the relationship between resistance, sampling period and pathotype. Penicillins and aminopenicillins, streptomycin, and tetracyclines were the most frequently prescribed antimicrobials and the greatest frequencies of resistance were detected to these 3 antimicrobial classes. A strong correlation (ρ=0.879) was observed between overall antimicrobial use and frequencies of antimicrobial resistance on farms. Sampling period was significant in the regression model for ampicillin resistance while pathotype was significant in the models for streptomycin, tetracycline and trimethoprim/sulphamethoxazole resistance. The frequencies of resistance observed have implications for veterinary therapeutics and prudent antimicrobial use. Resistance did not increase during the calving season and factors other than antimicrobial use, such as calf age and bacterial pathotype, may influence the occurrence of resistance in pathogenic E. coli.

  8. Antimicrobial Resistance and Molecular Epidemiology of Escherichia coli Causing Bloodstream Infections in Three Hospitals in Shanghai, China.

    Directory of Open Access Journals (Sweden)

    Su Wang

    Full Text Available Escherichia coli (E. coli is one of the most frequent and lethal causes of bloodstream infections (BSIs. We carried out a retrospective multicenter study on antimicrobial resistance and phylogenetic background of clinical E. coli isolates recovered from bloodstream in three hospitals in Shanghai. E. coli isolates causing BSIs were consecutively collected between Sept 2013 and Sept 2014. Ninety isolates randomly selected (30 from each hospital were enrolled in the study. Antimicrobial susceptibility testing was performed by disk diffusion. PCR was used to detect antimicrobial resistance genes coding for β-lactamases (TEM, CTX-M, OXA, etc., carbapenemases (IMP, VIM, KPC, NDM-1 and OXA-48, and phylogenetic groups. eBURST was applied for analysis of multi-locus sequence typing (MLST. The resistance rates for penicillins, second-generation cephalosporins, fluoroquinolone and tetracyclines were high (>60%. Sixty-one of the 90 (67.8% strains enrolled produced ESBLs and no carbapenemases were found. Molecular analysis showed that CTX-M-15 (25/61, CTX-M-14 (18/61 and CTX-M-55 (9/61 were the most common ESBLs. Phylogenetic group B2 predominated (43.3% and exhibited the highest rates of ESBLs production. ST131 (20/90 was the most common sequence type and almost assigned to phylogenetic group B2 (19/20. The following sequence types were ST405 (8/90 and ST69 (5/90. Among 61 ESBL-producers isolates, B2 (26, 42.6% and ST131 (18, 29.5% were also the most common phylogenetic group and sequence type. Genetic diversity showed no evidence suggesting a spread of these antimicrobial resistant isolates in the three hospitals. In order to provide more comprehensive and reliable epidemiological information for preventing further dissemination, well-designed and continuous surveillance with more hospitals participating was important.

  9. Antimicrobial Resistance and Molecular Epidemiology of Escherichia coli Causing Bloodstream Infections in Three Hospitals in Shanghai, China.

    Science.gov (United States)

    Wang, Su; Zhao, Sheng-Yuan; Xiao, Shu-Zhen; Gu, Fei-Fei; Liu, Qing-Zhong; Tang, Jin; Guo, Xiao-Kui; Ni, Yu-Xing; Han, Li-Zhong

    2016-01-01

    Escherichia coli (E. coli) is one of the most frequent and lethal causes of bloodstream infections (BSIs). We carried out a retrospective multicenter study on antimicrobial resistance and phylogenetic background of clinical E. coli isolates recovered from bloodstream in three hospitals in Shanghai. E. coli isolates causing BSIs were consecutively collected between Sept 2013 and Sept 2014. Ninety isolates randomly selected (30 from each hospital) were enrolled in the study. Antimicrobial susceptibility testing was performed by disk diffusion. PCR was used to detect antimicrobial resistance genes coding for β-lactamases (TEM, CTX-M, OXA, etc.), carbapenemases (IMP, VIM, KPC, NDM-1 and OXA-48), and phylogenetic groups. eBURST was applied for analysis of multi-locus sequence typing (MLST). The resistance rates for penicillins, second-generation cephalosporins, fluoroquinolone and tetracyclines were high (>60%). Sixty-one of the 90 (67.8%) strains enrolled produced ESBLs and no carbapenemases were found. Molecular analysis showed that CTX-M-15 (25/61), CTX-M-14 (18/61) and CTX-M-55 (9/61) were the most common ESBLs. Phylogenetic group B2 predominated (43.3%) and exhibited the highest rates of ESBLs production. ST131 (20/90) was the most common sequence type and almost assigned to phylogenetic group B2 (19/20). The following sequence types were ST405 (8/90) and ST69 (5/90). Among 61 ESBL-producers isolates, B2 (26, 42.6%) and ST131 (18, 29.5%) were also the most common phylogenetic group and sequence type. Genetic diversity showed no evidence suggesting a spread of these antimicrobial resistant isolates in the three hospitals. In order to provide more comprehensive and reliable epidemiological information for preventing further dissemination, well-designed and continuous surveillance with more hospitals participating was important.

  10. Identification of an integron containing the quinolone resistance gene qnrA1 in Shewanella xiamenensis.

    Science.gov (United States)

    Zhao, Jing-yi; Mu, Xiao-dong; Zhu, Yuan-qi; Xi, Lijun; Xiao, Zijun

    2015-09-01

    This study investigated multidrug resistance in Shewanella xiamenensis isolated from an estuarine water sample in China during 2014. This strain displayed resistance or decreased susceptibility to ampicillin, aztreonam, cefepime, cefotaxime, chloramphenicol, ciprofloxacin, erythromycin, kanamycin and trimethoprim-sulfamethoxazole. The antimicrobial resistance genes aacA3, blaOXA-199, qnrA1 and sul1 were identified by PCR amplification and by sequencing. Pulsed-field gel electrophoresis and DNA hybridization experiments showed that the quinolone resistance gene qnrA1 was chromosomally located. qnrA1 was located in a complex class 1 integron, downstream from an ISCR1, and bracketed by two copies of qacEΔ1-sul1 genes. This integron is similar to In825 with four gene cassettes aacA3, catB11c, dfrA1z and aadA2az. An IS26-mel-mph2-IS26 structure was also detected in the flanking sequences, conferring resistance to macrolides. This is the first identification of the class 1 integron in S. xiamenensis. This is also the first identification of the qnrA1 gene and IS26-mediated macrolide resistance genes in S. xiamenensis. Presence of a variety of resistance genetic determinants in environmental S. xiamenensis suggests the possibility that this species may serve as a potential vehicle of antimicrobial resistance genes in aquatic environments. PMID:26316545

  11. Temporal Trends in Antimicrobial Resistance and Virulence-Associated Traits within the Escherichia coli Sequence Type 131 Clonal Group and Its H30 and H30-Rx Subclones, 1968 to 2012

    OpenAIRE

    Olesen, Bente; Frimodt-Møller, Jakob; Leihof, Rikke Fleron; Struve, Carsten; Johnston, Brian; Hansen, Dennis S.; Scheutz, Flemming; Krogfelt, Karen A; Kuskowski, Michael A.; Clabots, Connie; Johnson, James R.

    2014-01-01

    To identify possible explanations for the recent global emergence of Escherichia coli sequence type (ST) 131 (ST131), we analyzed temporal trends within ST131 O25 for antimicrobial resistance, virulence genes, biofilm formation, and the H30 and H30-Rx subclones. For this, we surveyed the WHO E. coli and Klebsiella Centre's E. coli collection (1957 to 2011) for ST131 isolates, characterized them extensively, and assessed them for temporal trends. Overall, antimicrobial resistance increased tem...

  12. Heavy metal and disinfectant resistance genes among livestock-associated methicillin-resistant Staphylococcus aureus isolates.

    Science.gov (United States)

    Argudín, M Angeles; Lauzat, Birgit; Kraushaar, Britta; Alba, Patricia; Agerso, Yvonne; Cavaco, Lina; Butaye, Patrick; Porrero, M Concepción; Battisti, Antonio; Tenhagen, Bernd-Alois; Fetsch, Alexandra; Guerra, Beatriz

    2016-08-15

    Livestock associated methicillin-resistant Staphylococcus aureus (LA-MRSA) has emerged in animal production worldwide. Most LA-MRSA in Europe belong to the clonal complex (CC) 398. The reason for the LA-MRSA emergence is not fully understood. Besides antimicrobial agents used for therapy, other substances with antimicrobial activity applied in animal feed, including metal-containing compounds might contribute to their selection. Some of these genes have been found in various novel SCCmec cassettes. The aim of this study was to assess the occurrence of metal-resistance genes among a LA-S. aureus collection [n=554, including 542 MRSA and 12 methicillin-susceptible S. aureus (MSSA)] isolated from livestock and food thereof. Most LA-MRSA isolates (76%) carried at least one metal-resistance gene. Among the LA-MRSA CC398 isolates (n=456), 4.8%, 0.2%, 24.3% and 71.5% were positive for arsA (arsenic compounds), cadD (cadmium), copB (copper) and czrC (zinc/cadmium) resistance genes, respectively. In contrast, among the LA-MRSA non-CC398 isolates (n=86), 1.2%, 18.6% and 16.3% were positive for the cadD, copB and czrC genes, respectively, and none were positive for arsA. Of the LA-MRSA CC398 isolates, 72% carried one metal-resistance gene, and the remaining harboured two or more in different combinations. Differences between LA-MRSA CC398 and non-CC398 were statistically significant for arsA and czrC. The czrC gene was almost exclusively found (98%) in the presence of SCCmec V in both CC398 and non-CC398 LA-MRSA isolates from different sources. Regarding the LA-MSSA isolates (n=12), some (n=4) were also positive for metal-resistance genes. This study shows that genes potentially conferring metal-resistance are frequently present in LA-MRSA. PMID:27374912

  13. Heavy metal and disinfectant resistance genes among livestock-associated methicillin-resistant Staphylococcus aureus isolates.

    Science.gov (United States)

    Argudín, M Angeles; Lauzat, Birgit; Kraushaar, Britta; Alba, Patricia; Agerso, Yvonne; Cavaco, Lina; Butaye, Patrick; Porrero, M Concepción; Battisti, Antonio; Tenhagen, Bernd-Alois; Fetsch, Alexandra; Guerra, Beatriz

    2016-08-15

    Livestock associated methicillin-resistant Staphylococcus aureus (LA-MRSA) has emerged in animal production worldwide. Most LA-MRSA in Europe belong to the clonal complex (CC) 398. The reason for the LA-MRSA emergence is not fully understood. Besides antimicrobial agents used for therapy, other substances with antimicrobial activity applied in animal feed, including metal-containing compounds might contribute to their selection. Some of these genes have been found in various novel SCCmec cassettes. The aim of this study was to assess the occurrence of metal-resistance genes among a LA-S. aureus collection [n=554, including 542 MRSA and 12 methicillin-susceptible S. aureus (MSSA)] isolated from livestock and food thereof. Most LA-MRSA isolates (76%) carried at least one metal-resistance gene. Among the LA-MRSA CC398 isolates (n=456), 4.8%, 0.2%, 24.3% and 71.5% were positive for arsA (arsenic compounds), cadD (cadmium), copB (copper) and czrC (zinc/cadmium) resistance genes, respectively. In contrast, among the LA-MRSA non-CC398 isolates (n=86), 1.2%, 18.6% and 16.3% were positive for the cadD, copB and czrC genes, respectively, and none were positive for arsA. Of the LA-MRSA CC398 isolates, 72% carried one metal-resistance gene, and the remaining harboured two or more in different combinations. Differences between LA-MRSA CC398 and non-CC398 were statistically significant for arsA and czrC. The czrC gene was almost exclusively found (98%) in the presence of SCCmec V in both CC398 and non-CC398 LA-MRSA isolates from different sources. Regarding the LA-MSSA isolates (n=12), some (n=4) were also positive for metal-resistance genes. This study shows that genes potentially conferring metal-resistance are frequently present in LA-MRSA.

  14. Association between the consumption of antimicrobial agents in animal husbandry and the occurrence of resistant bacteria among food animals

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller

    1999-01-01

    Antimicrobial agents are used in food animals for therapy and prophylaxis of bacterial infections and in feed to promote growth. The use of antimicrobial agents for food animals may cause problems in the therapy of infections by selecting for resistance among bacteria pathogenic for animals...... animals, the quantitative impact of the use of different antimicrobial agents on selection for resistance and the most appropriate treatment regimens to limit the development of resistance is incomplete. Surveillance programmes monitoring the occurrence and development of resistance and consumption...... of antimicrobial agents are urgently needed, as is research into the most appropriate ways to use antimicrobial agents in veterinary medicine to limit the emergence and spread of antimicrobial resistance. (C) 1999 Elsevier Science B.V. and International Society of Chemotherapy. All rights reserved....

  15. New antimicrobial contact catalyst killing antibiotic resistant clinical and waterborne pathogens

    International Nuclear Information System (INIS)

    Microbial growth on medical and technical devices is a big health issue, particularly when microorganisms aggregate to form biofilms. Moreover, the occurrence of antibiotic-resistant bacteria in the clinical environment is dramatically growing, making treatment of bacterial infections very challenging. In search of an alternative, we studied a novel antimicrobial surface coating based on micro galvanic elements formed by silver and ruthenium with surface catalytic properties. The antimicrobial coating efficiently inhibited the growth of the nosocomial pathogens Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis and Enterococcus faecium as demonstrated by the growth inhibition on agar surface and in biofilms of antibiotic resistant clinical E. faecalis, E. faecium, and S. aureus isolates. It also strongly reduced the growth of Legionella in a drinking water pipeline and of Escherichia coli in urine. We postulate a mode of action of the antimicrobial material, which is independent of the release of silver ions. Thus, the novel antimicrobial coating could represent an alternative to combat microbial growth avoiding the toxic side effects of high levels of silver ions on eukaryotic cells. - Highlights: • The novel antimicrobial inhibits growth of clinical staphylococci and enterococci. • The novel antimicrobial inhibits growth of Legionella in drinking water. • A putative mode of action of the antimicrobial coating is presented

  16. New antimicrobial contact catalyst killing antibiotic resistant clinical and waterborne pathogens

    Energy Technology Data Exchange (ETDEWEB)

    Guridi, A. [Biophysics Unit (CSIC, UPV/EHU), Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa (Spain); Diederich, A.-K. [University Medical Center Freiburg, Division of Infectious Diseases, Hugstetter Strasse 55, 79106 Freiburg (Germany); Biology II, Microbiology, Albert-Ludwigs-University Freiburg, Schänzlestrasse 1, 79104 Freiburg (Germany); Aguila-Arcos, S.; Garcia-Moreno, M. [Biophysics Unit (CSIC, UPV/EHU), Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa (Spain); Blasi, R.; Broszat, M. [University Medical Center Freiburg, Division of Infectious Diseases, Hugstetter Strasse 55, 79106 Freiburg (Germany); Biology II, Microbiology, Albert-Ludwigs-University Freiburg, Schänzlestrasse 1, 79104 Freiburg (Germany); Schmieder, W.; Clauss-Lendzian, E. [Biology II, Microbiology, Albert-Ludwigs-University Freiburg, Schänzlestrasse 1, 79104 Freiburg (Germany); Sakinc-Gueler, T. [University Medical Center Freiburg, Division of Infectious Diseases, Hugstetter Strasse 55, 79106 Freiburg (Germany); Andrade, R. [Advanced Research Facilities (SGIker), University of the Basque Country, UPV/EHU, 48940 Leioa (Spain); Alkorta, I. [Biophysics Unit (CSIC, UPV/EHU), Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa (Spain); Meyer, C.; Landau, U. [Largentec GmbH, Am Waldhaus 32, 14129 Berlin (Germany); Grohmann, E., E-mail: elisabeth.grohmann@googlemail.com [Biophysics Unit (CSIC, UPV/EHU), Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa (Spain); University Medical Center Freiburg, Division of Infectious Diseases, Hugstetter Strasse 55, 79106 Freiburg (Germany); Biology II, Microbiology, Albert-Ludwigs-University Freiburg, Schänzlestrasse 1, 79104 Freiburg (Germany)

    2015-05-01

    Microbial growth on medical and technical devices is a big health issue, particularly when microorganisms aggregate to form biofilms. Moreover, the occurrence of antibiotic-resistant bacteria in the clinical environment is dramatically growing, making treatment of bacterial infections very challenging. In search of an alternative, we studied a novel antimicrobial surface coating based on micro galvanic elements formed by silver and ruthenium with surface catalytic properties. The antimicrobial coating efficiently inhibited the growth of the nosocomial pathogens Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis and Enterococcus faecium as demonstrated by the growth inhibition on agar surface and in biofilms of antibiotic resistant clinical E. faecalis, E. faecium, and S. aureus isolates. It also strongly reduced the growth of Legionella in a drinking water pipeline and of Escherichia coli in urine. We postulate a mode of action of the antimicrobial material, which is independent of the release of silver ions. Thus, the novel antimicrobial coating could represent an alternative to combat microbial growth avoiding the toxic side effects of high levels of silver ions on eukaryotic cells. - Highlights: • The novel antimicrobial inhibits growth of clinical staphylococci and enterococci. • The novel antimicrobial inhibits growth of Legionella in drinking water. • A putative mode of action of the antimicrobial coating is presented.

  17. Impact of media: self-medication and the rising problem of antimicrobial resistance

    OpenAIRE

    Manali M Mahajan; Sujata Dudhgaonkar

    2014-01-01

    Antimicrobial agents (AMAs) are one of the most commonly used as well as misused drugs. Antimicrobial resistance is an important growing global health issue which needs urgent addressal. Self-medication involves the use of medicinal products by the patient to treat self-recognized disorders, symptoms, recurrent diseases, or minor health problems. Medicines for self-medication are often called over the counter (OTC) drugs, which are available without a doctor's prescription through pharmaci...

  18. Antimicrobial and antibiofilm potential of biosurfactants isolated from lactobacilli against multi-drug-resistant pathogens

    OpenAIRE

    Sambanthamoorthy, Karthik; Feng, Xiaorong; Patel, Ruchi; PATEL, Sneha; Paranavitana, Chrysanthi

    2014-01-01

    Background Biosurfactants (BS) are amphiphilic compounds produced by microbes, either on the cell surface or secreted extracellularly. BS exhibit strong antimicrobial and anti-adhesive properties, making them good candidates for applications used to combat infections. In this study, our goal was to assess the in vitro antimicrobial, anti-adhesive and anti-biofilm abilities of BS produced by Lactobacillus jensenii and Lactobacillus rhamnosus against clinical Multidrug Resistant (MDR) strains o...

  19. CNS SPECIES AND ANTIMICROBIAL RESISTANCE IN CLINICAL AND SUBCLINICAL BOVINE MASTITIS

    OpenAIRE

    Persson Waller, K.; Aspán, A; Nyman, A.; Persson, Y.; Grönlund Andersson, U.

    2011-01-01

    Abstract Coagulase-negative staphylococci (CNS) are often associated with bovine mastitis. Knowledge about the relative importance of specific CNS species in different types of mastitis, and differences in antimicrobial resistance among CNS species is, however, scarce. Therefore, the aims of this study were to compare prevalence and antimicrobial susceptibility of CNS species in clinical and subclinical mastitis using material from two national surveys. Overall, S. chromogenes and ...

  20. Combating multidrug-resistant Gram-negative bacteria with structurally nanoengineered antimicrobial peptide polymers.

    Science.gov (United States)

    Lam, Shu J; O'Brien-Simpson, Neil M; Pantarat, Namfon; Sulistio, Adrian; Wong, Edgar H H; Chen, Yu-Yen; Lenzo, Jason C; Holden, James A; Blencowe, Anton; Reynolds, Eric C; Qiao, Greg G

    2016-01-01

    With the recent emergence of reports on resistant Gram-negative 'superbugs', infections caused by multidrug-resistant (MDR) Gram-negative bacteria have been named as one of the most urgent global health threats due to the lack of effective and biocompatible drugs. Here, we show that a class of antimicrobial agents, termed 'structurally nanoengineered antimicrobial peptide polymers' (SNAPPs) exhibit sub-μM activity against all Gram-negative bacteria tested, including ESKAPE and colistin-resistant and MDR (CMDR) pathogens, while demonstrating low toxicity. SNAPPs are highly effective in combating CMDR Acinetobacter baumannii infections in vivo, the first example of a synthetic antimicrobial polymer with CMDR Gram-negative pathogen efficacy. Furthermore, we did not observe any resistance acquisition by A. baumannii (including the CMDR strain) to SNAPPs. Comprehensive analyses using a range of microscopy and (bio)assay techniques revealed that the antimicrobial activity of SNAPPs proceeds via a multimodal mechanism of bacterial cell death by outer membrane destabilization, unregulated ion movement across the cytoplasmic membrane and induction of the apoptotic-like death pathway, possibly accounting for why we did not observe resistance to SNAPPs in CMDR bacteria. Overall, SNAPPs show great promise as low-cost and effective antimicrobial agents and may represent a weapon in combating the growing threat of MDR Gram-negative bacteria. PMID:27617798

  1. Streptococcus pneumoniae from Palestinian nasopharyngeal carriers: serotype distribution and antimicrobial resistance.

    Directory of Open Access Journals (Sweden)

    Abedelmajeed Nasereddin

    Full Text Available Infections of Streptococcus pneumoniae in children can be prevented by vaccination; left untreated, they cause high morbidity and fatalities. This study aimed at determining the nasopharyngeal carrier rates, serotype distribution and antimicrobial resistance patterns of S. pneumoniae in healthy Palestinian children under age two prior to the full introduction of the pneumococcal 7-valent conjugate vaccine (PCV7, which was originally introduced into Palestine in a pilot trial in September, 2010. In a cross sectional study, nasopharyngeal specimens were collected from 397 healthy children from different Palestinian districts between the beginning of November 2012 to the end of January 2013. Samples were inoculated into blood agar and suspected colonies were examined by amplifying the pneumococcal-specific autolysin gene using a real-time PCR. Serotypes were identified by a PCR that incorporated different sets of specific primers. Antimicrobial susceptibility was measured by disk diffusion and MIC methods. The resulting carrier rate of Streptococcus pneumoniae was 55.7% (221/397. The main serotypes were PCV7 serotypes 19F (12.2%, 23F (9.0%, 6B (8.6% and 14 (4% and PCV13 serotypes 6A (13.6% and 19A (4.1%. Notably, serotype 6A, not included in the pilot trial (PCV7 vaccine, was the most prevalent. Resistance to more than two drugs was observed for bacteria from 34.1% of the children (72/211 while 22.3% (47/211 carried bacteria were susceptible to all tested antibiotics. All the isolates were sensitive to cefotaxime and vancomycin. Any or all of these might impinge on the type and efficacy of the pneumococcal conjugate vaccines and antibiotics to be used for prevention and treatment of pneumococcal disease in the country.

  2. Increased survival of experimentally evolved antimicrobial peptide-resistant Staphylococcus aureus in an animal host.

    Science.gov (United States)

    Dobson, Adam J; Purves, Joanne; Rolff, Jens

    2014-09-01

    Antimicrobial peptides (AMPs) have been proposed as new class of antimicrobial drugs, following the increasing prevalence of bacteria resistant to antibiotics. Synthetic AMPs are functional analogues of highly evolutionarily conserved immune effectors in animals and plants, produced in response to microbial infection. Therefore, the proposed therapeutic use of AMPs bears the risk of 'arming the enemy': bacteria that evolve resistance to AMPs may be cross-resistant to immune effectors (AMPs) in their hosts. We used a panel of populations of Staphylococcus aureus that were experimentally selected for resistance to a suite of individual AMPs and antibiotics to investigate the 'arming the enemy' hypothesis. We tested whether the selected strains showed higher survival in an insect model (Tenebrio molitor) and cross-resistance against other antimicrobials in vitro. A population selected for resistance to the antimicrobial peptide iseganan showed increased in vivo survival, but was not more virulent. We suggest that increased survival of AMP-resistant bacteria almost certainly poses problems to immune-compromised hosts.

  3. Short communication: Prevalence, antimicrobial resistance, and resistant traits of coagulase-negative staphylococci isolated from cheese samples in Turkey.

    Science.gov (United States)

    Kürekci, Cemil

    2016-04-01

    A total of 17 coagulase-negative staphylococci (CNS) isolates obtained from 72 cheese samples were included in this study. Coagulase-negative staphylococci isolates obtained in this study comprised 6 (35.3%) Staphylococcus saprophyticus, 3 (17.6%) Staphylococcus epidermidis, 2 (11.8%) Staphylococcus hominis, 2 (11.8%) Staphylococcus haemolyticus, 1 (5.9%) Staphylococcus xylosus, 1 (5.9%) Staphylococcus vitulinus, 1 (5.9%) Staphylococcus lentus, and 1 (5.9%) Staphylococcus warneri. The disc diffusion assay revealed that the highest occurrence of resistance was found for penicillin (76.5%), erythromycin (35.3%), tetracycline (29.4%), and trimethoprim-sulfamethoxazole (17.6%) among CNS isolates. However, all CNS isolates were found to be susceptible to vancomycin, streptomycin, linezolid, and gentamycin. Of the isolates, 64.7% carried at least one of the following antimicrobial resistance genes: mecA, tet(M), erm(B), blaZ, ant(4')-la, aph(3')-IIIa, and lnu(A). The results suggest that improved hygienic conditions, such as safer handling of raw milk, proper cleaning, and sanitation during the manufacturing in the dairies, are urgently needed in Turkey. PMID:26874419

  4. Prevalence, antimicrobial resistance, and virulence characteristics of mecA-encoding coagulase-negative staphylococci isolated from soft cheese in Brazil.

    Science.gov (United States)

    Fontes, Cláudia Oliveira; Silva, Vânia Lúcia; de Paiva, Mayara Rodrigues Brandão; Garcia, Rafaela Alvim; Resende, Juliana Alves; Ferreira-Machado, Alessandra Barbosa; Diniz, Cláudio Galuppo

    2013-04-01

    Coagulase-negative staphylococci (CoNS), which are generally neglected as foodborne bacteria, are emerging as significant opportunistic pathogens that may be highly resistant to available antimicrobial drugs. In this study, antimicrobial susceptibility patterns, mecA gene occurrence, and virulence-associated characteristics were evaluated in CoNS isolated from soft cheese in Brazil. A total of 227 bacterial isolates were recovered from 35 cheese samples belonging to 5 batches with 7 different trademarks. The CoNS counts ranged from 10(6) to 10(7) CFU/g. High antimicrobial resistance percentages were observed for oxacillin (76.2%), penicillin (78.5%), erythromycin (67.8%), gentamicin (47.2%), clindamycin (35.7%), rifampicin (26.8%), azithromycin (14.7%), tetracycline (14.7%), levofloxacin (14.2%), and sulfamethoxazole-trimethoprim (11.9%). A low antimicrobial resistance percentage was observed for chloramphenicol (2.3%), and all of the tested bacteria were susceptible to vancomycin and linezolid. In total, a multiple antibiotic resistance (MAR) index of >0.2 was observed for 80.6% of the isolated CoNS. However, the MAR index ranged from 50% to 92.6% when only bacterial cheese isolates belonging to the same trademark were considered. Regarding to the prevalence of CoNS carrying mecA gene, 81.5% of the isolated strains were mecA(+) , and 76.2% of these were phenotypically resistant to oxacillin. Three isolates carried the enterotoxin A gene (sea), 29.5% produced biofilm in a laboratory test, and α- or ß-hemolysis were observed for 3% and 5.2%, respectively. This study highlights the extent of the antimicrobial resistance phenomenon in neglected foodborne microorganisms and the potential public health risks that are related to the consumption of CoNS-contaminated soft cheese.

  5. Evaluation of the Enterococcus faecalis Biofilm-Associated Virulence Factors AhrC and Eep in Rat Foreign Body Osteomyelitis and In Vitro Biofilm-Associated Antimicrobial Resistance

    OpenAIRE

    Kristi L Frank; Paschalis Vergidis; Brinkman, Cassandra L.; Greenwood Quaintance, Kerryl E.; Barnes, Aaron M.T.; Mandrekar, Jayawant N.; Patrick M Schlievert; Dunny, Gary M.; Robin Patel

    2015-01-01

    Enterococcus faecalis can cause healthcare-associated biofilm infections, including those of orthopedic devices. Treatment of enterococcal prosthetic joint infection is difficult, in part, due to biofilm-associated antimicrobial resistance. We previously showed that the E. faecalis OG1RF genes ahrC and eep are in vitro biofilm determinants and virulence factors in animal models of endocarditis and catheter-associated urinary tract infection. In this study, we evaluated the role of these genes...

  6. Antimicrobial drug resistance of Salmonella isolates from meat and humans, Denmark

    DEFF Research Database (Denmark)

    Skov, Marianne; Andersen, Jens Strodl; Aabo, Søren;

    2007-01-01

    We compared 8,144 Salmonella isolates collected from meat imported to or produced in Denmark, as well as from Danish patients. Isolates from imported meat showed a higher rate of antimicrobial drug resistance, including multidrug resistance, than did isolates from domestic meat. Isolates from hum...... humans showed resistance rates lower than those found in imported meat but higher than in domestic meat. These findings indicate that programs for controlling resistant Salmonella spp. are a global issue.......We compared 8,144 Salmonella isolates collected from meat imported to or produced in Denmark, as well as from Danish patients. Isolates from imported meat showed a higher rate of antimicrobial drug resistance, including multidrug resistance, than did isolates from domestic meat. Isolates from...

  7. Antimicrobial drug resistance of Salmonella isolates from meat and humans, Denmark

    DEFF Research Database (Denmark)

    Skov, Marianne Nielsine; Andersen, Jens Strodl; Aabo, Søren;

    2007-01-01

    We compared 8,144 Salmonella isolates collected from meat imported to or produced in Denmark, as well as from Danish patients. Isolates from imported meat showed a higher rate of antimicrobial drug resistance, including multidrug resistance, than did isolates from domestic meat. Isolates from hum...... humans showed resistance rates lower than those found in imported meat but higher than in domestic meat. These findings indicate that programs for controlling resistant Salmonella spp. are a global issue......We compared 8,144 Salmonella isolates collected from meat imported to or produced in Denmark, as well as from Danish patients. Isolates from imported meat showed a higher rate of antimicrobial drug resistance, including multidrug resistance, than did isolates from domestic meat. Isolates from...

  8. A new strategy to fight antimicrobial resistance: the revival of old antibiotics

    Directory of Open Access Journals (Sweden)

    Nadim eCassir

    2014-10-01

    Full Text Available The increasing prevalence of hospital- and community-acquired infections caused by multidrug-resistant bacterial pathogens is limiting the options for effective antibiotic therapy. Moreover, this alarming spread of antimicrobial resistance has not been paralleled by the development of novel antimicrobials. Resistance to the scarce new antibiotics is also emerging. In this context, the rational use of older antibiotics could represent an alternative for the treatment of multidrug-resistant bacterial pathogens. This strategy would help to optimize the armamentarium of antibiotics so as to preserve the effectiveness of new antibiotics and avoid the prescription of drugs known to favor the spread of resistance (i.e., quinolones. Furthermore, from a global economic perspective, this strategy could be useful in public health, given that several of these cheapest forgotten antibiotics are not available in many countries. We will review here the successful treatment of multidrug-resistant bacterial infections with old antibiotics and discuss their place in current practice.

  9. Evaluation of the Enterococcus faecalis Biofilm-Associated Virulence Factors AhrC and Eep in Rat Foreign Body Osteomyelitis and In Vitro Biofilm-Associated Antimicrobial Resistance.

    Directory of Open Access Journals (Sweden)

    Kristi L Frank

    Full Text Available Enterococcus faecalis can cause healthcare-associated biofilm infections, including those of orthopedic devices. Treatment of enterococcal prosthetic joint infection is difficult, in part, due to biofilm-associated antimicrobial resistance. We previously showed that the E. faecalis OG1RF genes ahrC and eep are in vitro biofilm determinants and virulence factors in animal models of endocarditis and catheter-associated urinary tract infection. In this study, we evaluated the role of these genes in a rat acute foreign body osteomyelitis model and in in vitro biofilm-associated antimicrobial resistance. Osteomyelitis was established for one week following the implantation of stainless steel orthopedic wires inoculated with E. faecalis strains OG1RF, ΩahrC, and ∆eep into the proximal tibiae of rats. The median bacterial loads recovered from bones and wires did not differ significantly between the strains at multiple inoculum concentrations. We hypothesize that factors present at the infection site that affect biofilm formation, such as the presence or absence of shear force, may account for the differences in attenuation in the various animal models we have used to study the ΩahrC and ∆eep strains. No differences among the three strains were observed in the planktonic and biofilm antimicrobial susceptibilities to ampicillin, vancomycin, daptomycin, linezolid, and tetracycline. These findings suggest that neither ahrC nor eep directly contribute to E. faecalis biofilm-associated antimicrobial resistance. Notably, the experimental evidence that the biofilm attachment mutant ΩahrC displays biofilm-associated antimicrobial resistance suggests that surface colonization alone is sufficient for E. faecalis cells to acquire the biofilm antimicrobial resistance phenotype.

  10. Evaluation of the Enterococcus faecalis Biofilm-Associated Virulence Factors AhrC and Eep in Rat Foreign Body Osteomyelitis and In Vitro Biofilm-Associated Antimicrobial Resistance.

    Science.gov (United States)

    Frank, Kristi L; Vergidis, Paschalis; Brinkman, Cassandra L; Greenwood Quaintance, Kerryl E; Barnes, Aaron M T; Mandrekar, Jayawant N; Schlievert, Patrick M; Dunny, Gary M; Patel, Robin

    2015-01-01

    Enterococcus faecalis can cause healthcare-associated biofilm infections, including those of orthopedic devices. Treatment of enterococcal prosthetic joint infection is difficult, in part, due to biofilm-associated antimicrobial resistance. We previously showed that the E. faecalis OG1RF genes ahrC and eep are in vitro biofilm determinants and virulence factors in animal models of endocarditis and catheter-associated urinary tract infection. In this study, we evaluated the role of these genes in a rat acute foreign body osteomyelitis model and in in vitro biofilm-associated antimicrobial resistance. Osteomyelitis was established for one week following the implantation of stainless steel orthopedic wires inoculated with E. faecalis strains OG1RF, ΩahrC, and ∆eep into the proximal tibiae of rats. The median bacterial loads recovered from bones and wires did not differ significantly between the strains at multiple inoculum concentrations. We hypothesize that factors present at the infection site that affect biofilm formation, such as the presence or absence of shear force, may account for the differences in attenuation in the various animal models we have used to study the ΩahrC and ∆eep strains. No differences among the three strains were observed in the planktonic and biofilm antimicrobial susceptibilities to ampicillin, vancomycin, daptomycin, linezolid, and tetracycline. These findings suggest that neither ahrC nor eep directly contribute to E. faecalis biofilm-associated antimicrobial resistance. Notably, the experimental evidence that the biofilm attachment mutant ΩahrC displays biofilm-associated antimicrobial resistance suggests that surface colonization alone is sufficient for E. faecalis cells to acquire the biofilm antimicrobial resistance phenotype. PMID:26076451

  11. Impact of integrated fish farming on antimicrobial resistance in a pond environment

    DEFF Research Database (Denmark)

    Petersen, Andreas; Andersen, Jens Strodl; Kaewmak, T.;

    2002-01-01

    investigated the impact of integrated fish farming on the levels of antimicrobial-resistant bacteria in a pond environment. One integrated broiler chicken-fish farm was studied for 2 months immediately after the start of a new fish production cycle. A significant increase over time in the resistance to six......-resistant bacteria from animal manure. Potential risks to human health were not addressed in this study and remain to be elucidated....

  12. Molecular Characterization and Antimicrobial Susceptibility of Fluoroquinolone-Resistant or -Susceptible Streptococcus pneumoniae from Hong Kong

    OpenAIRE

    Morrissey, Ian; Farrell, David J.; Bakker, Sarah; Buckridge, Sylvie; Felmingham, David

    2003-01-01

    Fluoroquinolone resistance in Streptococcus pneumoniae isolated from Hong Kong as part of Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin 1999/2000 was found to be due to the spread of the Spain23F-1 clone (mainly a Spain23F-1-14 variant). All the isolates were multidrug resistant but were susceptible to quinupristin-dalfopristin, linezolid, and telithromycin. The Spain23F-1 clone also occurred among antimicrobial-susceptible isolates, which suggests th...

  13. spa typing and antimicrobial resistance of Staphylococcus aureus from healthy humans, pigs and dogs in Tanzania

    DEFF Research Database (Denmark)

    Katakweba, Abdul S.; Muhairwa, Amandus P.; Espinosa-Gongora, Carmen;

    2016-01-01

    from 100 humans, 100 pigs and 100 dogs in Morogoro Municipal. Each swab was enriched in Mueller Hinton broth with 6.5% NaCl and subcultured on chromogenic agar for S. aureus detection. Presumptive S. aureus colonies were confirmed to the species level by nuc PCR and analysed by spa typing....... Antimicrobial susceptibility patterns were determined by disc diffusion method. Results: S. aureus was isolated from 22 % of humans, 4 % of pigs and 11 % of dogs. A total of 21 spa types were identified: 13, 7 and 1 in human, dogs, and pigs, respectively. Three spa types (t314, t223 and t084) were shared...... between humans and dogs. A novel spa type (t10779) was identified in an isolate recovered from a colonized human. Antimicrobials tested revealed resistance to ampicillin in all isolates, moderate resistances to other antimicrobials with tetracycline resistance being the most frequent. Conclusion: S...

  14. Antimicrobial resistance of Staphylococcus species isolated from Lebanese dairy-based products.

    Science.gov (United States)

    Zouhairi, O; Saleh, I; Alwan, N; Toufeili, I; Barbour, E; Harakeh, S

    2012-12-04

    The study evaluated the antimicrobial resistance of molecularly characterized strains of Staphylococcus aureus and S. saprophyticus isolated from 3 Lebanese dairy-based food products that are sometimes consumed raw: kishk, shanklish and baladi cheese. Suspected Staphylococcus isolates were identified initially using standard biochemical tests, then strains that were confirmed by polymerase chain reaction (29 S. aureus and 17 S. saprophyticus) were evaluated for their susceptibility to different antimicrobials. The highest levels of contamination with staphylococci were in baladi cheese. Resistance rates ranged from 67% to gentamicin to 94% to oxacillin and clindamycin. The results suggest that these locally made dairy-based foods may act as vehicles for the transmission of antimicrobial-resistant Staphylococcus spp.

  15. Antimicrobial resistance, virulence determinants and genetic profiles of clinical and nonclinical Enterococcus cecorum from poultry.

    Science.gov (United States)

    Jackson, C R; Kariyawasam, S; Borst, L B; Frye, J G; Barrett, J B; Hiott, L M; Woodley, T A

    2015-02-01

    Enterococcus cecorum has been implicated as a possible cause of disease in poultry. However, the characteristics that contribute to pathogenesis of Ent. cecorum in poultry have not been defined. In this study, Ent. cecorum from carcass rinsates (n = 75) and diseased broilers and broiler breeders (n = 30) were compared based upon antimicrobial resistance phenotype, the presence of virulence determinants and genetic relatedness using pulsed-field gel electrophoresis (PFGE). Of the 16 antimicrobials tested, Ent. cecorum from carcass rinsates and clinical cases were resistant to ten and six of the antimicrobials, respectively. The majority of Ent. cecorum from carcass rinsates was resistant to lincomycin (54/75; 72%) and tetracycline (46/75; 61.3%) while the highest level of resistance among clinical Ent. cecorum was to tetracycline (22/30; 73.3%) and erythromycin (11/30; 36.7%). Multidrug resistance (resistance to ≥2 antimicrobials) was identified in Ent. cecorum from carcass rinsates (53/75; 70.7%) and diseased poultry (18/30; 60%). Of the virulence determinants tested, efaAfm was present in almost all of the isolates (104/105; 99%). Using PFGE, the majority of clinical isolates clustered together; however, a few clinical isolates grouped with Ent. cecorum from carcass rinsates. These data suggest that distinguishing the two groups of isolates is difficult based upon the characterization criteria used.

  16. The Evolution of Antimicrobial Resistance in Respiratory Pathogens in Canada: What are the Clinical Consequences?

    Directory of Open Access Journals (Sweden)

    Donald E Low

    1998-01-01

    Full Text Available The use of antimicrobial agents has led to reductions in illnesses and deaths from a variety of infectious diseases. Antimicrobial resistance has followed the introduction of almost every new antimicrobial agent and is now emerging as an important public health problem, especially in respiratory tract pathogens in the community. During the past decade in Canada, a rapid and relentless increase in antimicrobial resistance in Streptococcus pneumoniae and Haemophilus inflluenzae has been witnessed. Adverse implications as a result of the treatment of an infection with an antibiotic to which the offending pathogen is resistant have been recognized in only a few infectious disease syndromes (eg. bacterial meningitis. More often, resistance in vitro does not result in resistance in vivo (eg, respiratory tract infections. Therefore, before recommendations regarding empirical or directed therapy are changed, it is essential that evidence to support those decisions is obtained. More important, the prevention and control of such resistance must be addressed by reducing the burden of antibiotic selective pressure by curtailing inappropriate antibiotic use.

  17. Multilocus sequence typing and antimicrobial resistance of Campylobacter jejuni isolated from dairy calves in Austria

    Directory of Open Access Journals (Sweden)

    Daniela eKlein-Jöbstl

    2016-02-01

    Full Text Available Human campylobacteriosis is primarily associated with poultry but also cattle. In this study, 55 Campylobacter jejuni strains isolated from 382 dairy calves’ feces were differentiated by multilocus sequence typing and tested for antimicrobial resistance. The most prevalent sequence type (ST was ST883 (20.0%, followed by ST48 (14.5%, and ST50 (9.1%. In contrast to ST48 and ST50, ST883 has rarely been described in cattle previously. Furthermore, risk factor analysis was performed for the presence of the most prevalent STs in these calves. Multiple regression analysis revealed that the type of farm (organic versus conventional and calf housing (place, and individual versus group were identified as significantly (p<0.05 associated with the presence of ST883 in calves, and ST50 was associated with calf diarrhea. Antimicrobial resistance was detected in 58.2% of the isolates. Most of the resistant isolates (81.3% were resistant to more than one antimicrobial. Most frequently, resistance to ciprofloxacin (49.1%, followed by nalidixic acid with (42.8%, and tetracycline (14.5% was observed. The results of the present study support the hypothesis that dairy calves may serve as a potential reservoir for Campylobacter jejuni and pose a risk for transmission, including antimicrobial resistant isolates to the environment and to humans.

  18. Antimicrobial resistance predicts death in Tanzanian children with bloodstream infections: a prospective cohort study

    Directory of Open Access Journals (Sweden)

    Msangi Viola

    2007-05-01

    Full Text Available Abstract Background Bloodstream infection is a common cause of hospitalization, morbidity and death in children. The impact of antimicrobial resistance and HIV infection on outcome is not firmly established. Methods We assessed the incidence of bloodstream infection and risk factors for fatal outcome in a prospective cohort study of 1828 consecutive admissions of children aged zero to seven years with signs of systemic infection. Blood was obtained for culture, malaria microscopy, HIV antibody test and, when necessary, HIV PCR. We recorded data on clinical features, underlying diseases, antimicrobial drug use and patients' outcome. Results The incidence of laboratory-confirmed bloodstream infection was 13.9% (255/1828 of admissions, despite two thirds of the study population having received antimicrobial therapy prior to blood culture. The most frequent isolates were klebsiella, salmonellae, Escherichia coli, enterococci and Staphylococcus aureus. Furthermore, 21.6% had malaria and 16.8% HIV infection. One third (34.9% of the children with laboratory-confirmed bloodstream infection died. The mortality rate from Gram-negative bloodstream infection (43.5% was more than double that of malaria (20.2% and Gram-positive bloodstream infection (16.7%. Significant risk factors for death by logistic regression modeling were inappropriate treatment due to antimicrobial resistance, HIV infection, other underlying infectious diseases, malnutrition and bloodstream infection caused by Enterobacteriaceae, other Gram-negatives and candida. Conclusion Bloodstream infection was less common than malaria, but caused more deaths. The frequent use of antimicrobials prior to blood culture may have hampered the detection of organisms susceptible to commonly used antimicrobials, including pneumococci, and thus the study probably underestimates the incidence of bloodstream infection. The finding that antimicrobial resistance, HIV-infection and malnutrition predict fatal

  19. Antimicrobial Resistance Spread and the Role of Mobile Genetic Elements

    NARCIS (Netherlands)

    M.A. Khan (Mushtaq Ahmad)

    2010-01-01

    textabstractAlexander Fleming discovered the first antimicrobial agent, penicillin (a β-lactam), in 1928 in the mold Penicillium notatum. Penicillin was initially found to be active against staphylococcal strains, which at that time were a major source of infectious diseases. Indeed, the mortality r

  20. Novel Genes Related to Ceftriaxone Resistance Found among Ceftriaxone-Resistant Neisseria gonorrhoeae Strains Selected In Vitro.

    Science.gov (United States)

    Gong, Zijian; Lai, Wei; Liu, Min; Hua, Zhengshuang; Sun, Yayin; Xu, Qingfang; Xia, Yue; Zhao, Yue; Xie, Xiaoyuan

    2016-04-01

    The emergence of ceftriaxone-resistantNeisseria gonorrhoeaeis currently a global public health concern. However, the mechanism of ceftriaxone resistance is not yet fully understood. To investigate the potential genes related to ceftriaxone resistance inNeisseria gonorrhoeae, we subcultured six gonococcal strains with increasing concentrations of ceftriaxone and isolated the strains that became resistant. After analyzing several frequently reported genes involved in ceftriaxone resistance, we found only a single mutation inpenA(A501V). However, differential analysis of the genomes and transcriptomes between pre- and postselection strains revealed many other mutated genes as well as up- and downregulated genes. Transformation of the mutatedpenAgene into nonresistant strains increased the MIC between 2.0- and 5.3-fold, and transformation of mutatedftsXincreased the MIC between 3.3- and 13.3-fold. Genes encoding the ABC transporters FarB, Tfq, Hfq, and ExbB were overexpressed, whilepilM,pilN, andpilQwere downregulated. Furthermore, the resistant strain developed cross-resistance to penicillin and cefuroxime, had an increased biochemical metabolic rate, and presented fitness defects such as prolonged growth time and downregulated PilMNQ. In conclusion, antimicrobial pressure could result in the emergence of ceftriaxone resistance, and the evolution of resistance ofNeisseria gonorrhoeaeto ceftriaxone is a complicated process at both the pretranscriptional and posttranscriptional levels, involving several resistance mechanisms of increased efflux and decreased entry. PMID:26787702

  1. Novel Genes Related to Ceftriaxone Resistance Found among Ceftriaxone-Resistant Neisseria gonorrhoeae Strains Selected In Vitro.

    Science.gov (United States)

    Gong, Zijian; Lai, Wei; Liu, Min; Hua, Zhengshuang; Sun, Yayin; Xu, Qingfang; Xia, Yue; Zhao, Yue; Xie, Xiaoyuan

    2016-04-01

    The emergence of ceftriaxone-resistantNeisseria gonorrhoeaeis currently a global public health concern. However, the mechanism of ceftriaxone resistance is not yet fully understood. To investigate the potential genes related to ceftriaxone resistance inNeisseria gonorrhoeae, we subcultured six gonococcal strains with increasing concentrations of ceftriaxone and isolated the strains that became resistant. After analyzing several frequently reported genes involved in ceftriaxone resistance, we found only a single mutation inpenA(A501V). However, differential analysis of the genomes and transcriptomes between pre- and postselection strains revealed many other mutated genes as well as up- and downregulated genes. Transformation of the mutatedpenAgene into nonresistant strains increased the MIC between 2.0- and 5.3-fold, and transformation of mutatedftsXincreased the MIC between 3.3- and 13.3-fold. Genes encoding the ABC transporters FarB, Tfq, Hfq, and ExbB were overexpressed, whilepilM,pilN, andpilQwere downregulated. Furthermore, the resistant strain developed cross-resistance to penicillin and cefuroxime, had an increased biochemical metabolic rate, and presented fitness defects such as prolonged growth time and downregulated PilMNQ. In conclusion, antimicrobial pressure could result in the emergence of ceftriaxone resistance, and the evolution of resistance ofNeisseria gonorrhoeaeto ceftriaxone is a complicated process at both the pretranscriptional and posttranscriptional levels, involving several resistance mechanisms of increased efflux and decreased entry.

  2. Emerging Infectious Diseases, Antimicrobial Resistance and Millennium Development Goals: Resolving the Challenges through One Health

    Directory of Open Access Journals (Sweden)

    G. V. Asokan

    2014-01-01

    Full Text Available Most emerging infectious diseases are zoonoses, which could severely hamper reaching the targets of millennium development goals (MDG. Five out of the total eight MDG’s are strongly associated with the Emerging Infectious Diseases (EIDs. Recent emergence and dissemination of drug-resistant pathogens has accelerated and prevent reaching the targets of MDG, with shrinking of therapeutic arsenal, mostly due to antimicrobial resistance (AMR. World Health Organization (WHO has identified AMR as 1 of the 3 greatest threats to global health. Until now, methicillin-resistant staphylococcus aureus (MRSA and vancomycin-resistant enterococci (VRE have been observed in hospital-acquired infections. In India, within a span of three years, New Delhi metallo-β-lactamase prevalence has risen from three percent in hospitals to twenty- fifty percent and is found to be colistin resistant as well. Routine use of antimicrobials in animal husbandry accounts for more than 50% in tonnage of all antimicrobial production to promote growth and prophylaxis. This has consequences to human health and environmental contamination with a profound impact on the environmental microbiome, resulting in resistance. Antibiotic development is now considered a global health crisis. The average time required to receive regulatory approval is 7.2 years. Moreover, the clinical approval success is only 16%. To overcome resistance in antimicrobials, intersectoral partnerships among medical, veterinary, and environmental disciplines, with specific epidemiological, diagnostic, and therapeutic approaches are needed. Joint efforts under “One Health”, beyond individual professional boundaries are required to stop antimicrobial resistance against zoonoses (EID and reach the MDG.

  3. Free-Ranging Frigates (Fregata magnificens) of the Southeast Coast of Brazil Harbor Extraintestinal Pathogenic Escherichia coli Resistant to Antimicrobials.

    Science.gov (United States)

    Saviolli, Juliana Yuri; Cunha, Marcos Paulo Vieira; Guerra, Maria Flávia Lopes; Irino, Kinue; Catão-Dias, José Luiz; de Carvalho, Vania Maria

    2016-01-01

    Seabirds may be responsible for the spread of pathogenic/resistant organisms over great distances, playing a relevant role within the context of the One World, One Health concept. Diarrheagenic E. coli strains, known as STEC (shiga toxin-producing E. coli), and the extraintestinal pathogenic E. coli (ExPEC and the subpathotype APEC), are among the E. coli pathotypes with zoonotic potential associated with the birds. In order to identify health threats carried by frigates and to evaluate the anthropic influence on the southern coast of Brazil, the aim of this work was to characterize E. coli isolated from free-ranging frigates in relation to virulence genotypes, serotypes, phylogenetic groups and antimicrobial resistance. Cloacal and choanal swabs were sampled from 38 Fregata magnificens from two oceanic islands and one rescue center. Forty-three E. coli strains were recovered from 33 out of the 38 birds (86.8%); 88.4% of strains showed some of the virulence genes (VGs) searched, 48.8% contained three or more VGs. None of the strains presented VGs related to EPEC/STEC. Some of the isolates showed virulence genotypes, phylogenetic groups and serotypes of classical human ExPEC or APEC (O2:H7, O1:H6, ONT:H7, O25:H4). Regarding antimicrobial susceptibility, 62.8% showed resistance, and 11.6% (5/43) were multidrug-resistant. The E. coli present in the intestines of the frigates may reflect the environmental human impact on southeast coast of Brazil; they may also represent an unexplored threat for seabird species, especially considering the overlap of pathogenic potential and antimicrobial resistance present in these strains. PMID:26845679

  4. Free-Ranging Frigates (Fregata magnificens of the Southeast Coast of Brazil Harbor Extraintestinal Pathogenic Escherichia coli Resistant to Antimicrobials.

    Directory of Open Access Journals (Sweden)

    Juliana Yuri Saviolli

    Full Text Available Seabirds may be responsible for the spread of pathogenic/resistant organisms over great distances, playing a relevant role within the context of the One World, One Health concept. Diarrheagenic E. coli strains, known as STEC (shiga toxin-producing E. coli, and the extraintestinal pathogenic E. coli (ExPEC and the subpathotype APEC, are among the E. coli pathotypes with zoonotic potential associated with the birds. In order to identify health threats carried by frigates and to evaluate the anthropic influence on the southern coast of Brazil, the aim of this work was to characterize E. coli isolated from free-ranging frigates in relation to virulence genotypes, serotypes, phylogenetic groups and antimicrobial resistance. Cloacal and choanal swabs were sampled from 38 Fregata magnificens from two oceanic islands and one rescue center. Forty-three E. coli strains were recovered from 33 out of the 38 birds (86.8%; 88.4% of strains showed some of the virulence genes (VGs searched, 48.8% contained three or more VGs. None of the strains presented VGs related to EPEC/STEC. Some of the isolates showed virulence genotypes, phylogenetic groups and serotypes of classical human ExPEC or APEC (O2:H7, O1:H6, ONT:H7, O25:H4. Regarding antimicrobial susceptibility, 62.8% showed resistance, and 11.6% (5/43 were multidrug-resistant. The E. coli present in the intestines of the frigates may reflect the environmental human impact on southeast coast of Brazil; they may also represent an unexplored threat for seabird species, especially considering the overlap of pathogenic potential and antimicrobial resistance present in these strains.

  5. Human health hazard from antimicrobial-resistant enterococci in animals and food

    DEFF Research Database (Denmark)

    Heuer, Ole Eske; Hammerum, Anette Marie; Collignon, P.;

    2006-01-01

    . The potential hazard to human health from antimicrobial-resistant enterococci in animals is questioned by some scientists because of evidence of host specificity of enterococci. Similarly, the occurrences of specific nosocomial clones of enterococci in hospitals have lead to the misconception that antimicrobial......-resistant animal enterococci should be disregarded as a human health hazard. On the basis of review of the literature, we find that neither the results provided by molecular typing that classify enterococci as host-specific organisms nor the occurrence of specific nosocomial clones of enterococci provide reasons...

  6. Enteric bacterial pathogens in children with diarrhea in Niger: diversity and antimicrobial resistance.

    Directory of Open Access Journals (Sweden)

    Céline Langendorf

    Full Text Available Although rotavirus is the leading cause of severe diarrhea among children in sub-Saharan Africa, better knowledge of circulating enteric pathogenic bacteria and their antimicrobial resistance is crucial for prevention and treatment strategies.As a part of rotavirus gastroenteritis surveillance in Maradi, Niger, we performed stool culture on a sub-population of children under 5 with moderate-to-severe diarrhea between April 2010 and March 2012. Campylobacter, Shigella and Salmonella were sought with conventional culture and biochemical methods. Shigella and Salmonella were serotyped by slide agglutination. Enteropathogenic Escherichia coli (EPEC were screened by slide agglutination with EPEC O-typing antisera and confirmed by detection of virulence genes. Antimicrobial susceptibility was determined by disk diffusion. We enrolled 4020 children, including 230 with bloody diarrhea. At least one pathogenic bacterium was found in 28.0% of children with watery diarrhea and 42.2% with bloody diarrhea. Mixed infections were found in 10.3% of children. EPEC, Salmonella and Campylobacter spp. were similarly frequent in children with watery diarrhea (11.1%, 9.2% and 11.4% respectively and Shigella spp. were the most frequent among children with bloody diarrhea (22.1%. The most frequent Shigella serogroup was S. flexneri (69/122, 56.5%. The most frequent Salmonella serotypes were Typhimurimum (71/355, 20.0%, Enteritidis (56/355, 15.8% and Corvallis (46/355, 13.0%. The majority of putative EPEC isolates was confirmed to be EPEC (90/111, 81.1%. More than half of all Enterobacteriaceae were resistant to amoxicillin and co-trimoxazole. Around 13% (46/360 Salmonella exhibited an extended-spectrum beta-lactamase phenotype.This study provides updated information on enteric bacteria diversity and antibiotic resistance in the Sahel region, where such data are scarce. Whether they are or not the causative agent of diarrhea, bacterial infections and their antibiotic

  7. Isolation, Virulence, and Antimicrobial Resistance of Methicillin-Resistant Staphylococcus aureus (MRSA) and Methicillin Sensitive Staphylococcus aureus (MSSA) Strains from Oklahoma Retail Poultry Meats.

    Science.gov (United States)

    Abdalrahman, Lubna S; Stanley, Adriana; Wells, Harrington; Fakhr, Mohamed K

    2015-05-29

    Staphylococcus aureus is one the top five pathogens causing domestically acquired foodborne illness in the U.S. Only a few studies are available related to the prevalence of S. aureus and MRSA in the U.S. retail poultry industry. The objectives of this study were to determine the prevalence of S. aureus (MSSA and MRSA) in retail chicken and turkey meats sold in Tulsa, Oklahoma and to characterize the recovered strains for their antimicrobial resistance and possession of toxin genes. A total of 167 (114 chicken and 53 turkey) retail poultry samples were used in this study. The chicken samples included 61 organic samples while the rest of the poultry samples were conventional. The overall prevalence of S. aureus was 57/106 (53.8%) in the conventional poultry samples and 25/61 (41%) in the organic ones. Prevalence in the turkey samples (64.2%) was higher than in the chicken ones (42.1%). Prevalence of S. aureus did not vary much between conventional (43.4%) and organic chicken samples (41%). Two chicken samples 2/114 (1.8%) were positive for MRSA. PFGE identified the two MRSA isolates as belonging to PFGE type USA300 (from conventional chicken) and USA 500 (from organic chicken) which are community acquired CA-MRSA suggesting a human based source of contamination. MLST and spa typing also supported this conclusion. A total of 168 Staphylococcus aureus isolates (101 chicken isolates and 67 turkey isolates) were screened for their antimicrobial susceptibility against 16 antimicrobials and their possession of 18 different toxin genes. Multidrug resistance was higher in the turkey isolates compared to the chicken ones and the percentage of resistance to most of the antimicrobials tested was also higher among the turkey isolates. The hemolysin hla and hld genes, enterotoxins seg and sei, and leucocidins lukE-lukD were more prevalent in the chicken isolates. The PVL gene lukS-lukF was detected only in chicken isolates including the MRSA ones. In conclusion, S. aureus is

  8. Antimicrobial resistance and molecular epidemiology of Salmonella Rissen from animals, food products, and patients in Thailand and Denmark

    DEFF Research Database (Denmark)

    Hendriksen, Rene S.; Bangtrakulnonth, Aroon; Pulsrikarn, Chaiwat;

    2008-01-01

    Rissen isolates recovered from humans, food products, and animals in Denmark and Thailand. Additionally, risk factors due to travel and consumption of specific food products were analyzed and evaluated. A total of 112 Salmonella Rissen isolates were included in this study from Thailand and Denmark. Thai...... isolates were recovered from humans, uncooked food, and ready-to-eat food. Danish isolates were obtained from humans (with and without a history of travel to Thailand prior to the infection), Danish pig or pork products, imported pig or pork products, turkeys, and animal feed. A total of 63 unique Xba......IPFGE patterns were observed. The predominant pattern was shared by 22 strains. Limited antimicrobial resistance was observed in the Danish strains, and a higher degree of resistance was observed in strains originating from Thailand. Virtually all isolates were resistant to tetracycline. The tetA gene...

  9. RETROSPECTIVE STUDY OF ANTIMICROBIAL RESIDUES AND RESISTANCE IN SWINE IN ABA ABIA STATE, NIGERIA

    Directory of Open Access Journals (Sweden)

    P. NWIYI

    2014-05-01

    Full Text Available Antimicrobials are used by livestock farmers to prevent and control infection. Antimicrobials are also included at sub-therapeutic doses in animal feed as growth promoters and to improve feed efficiency in intensive farming. The aim of this study was to evaluate the antimicrobial residues and resistance that could arise due to antimicrobial use in swine. The study was carried out between September 10th and December 10th 2013 in some selected swine farms in Ogbor Hill water side in Aba, Abia state. The study involved visiting the various farms, evaluating the records of previous treatment. Also the state zonal veterinary clinics visited and record of farms was collected for analysis. From the result obtained, in raining season in a given year, the frequency of tetracycline usage recorded 83.3%, penicillin recorded 75.0%, while sulfonamide recorded 25.0%. Tylosin and ivermox were the least and recorded 8.4% usage each. The swine treatment was done by the farmers hence there was consistent over-dosage of antimicrobials to the pigs as the manufacture’s guide was not complied with. The report from the records showed that some of the pigs were slaughtered and sold in the market at any time without recourse to drug with-draw. This result could be one of the responsible reasons for antimicrobial residues and resistance in swine and indeed livestock.

  10. Prevalence of antimicrobial resistance among bacterial pathogens isolated from cattle in different European countries: 2002–2004

    DEFF Research Database (Denmark)

    Hendriksen, Rene S.; Mevius, Dik J; Schroeter, Andreas;

    2008-01-01

    from 13 European countries. For Staphylococcus aureus from bovine mastitis major differences were apparent in the occurrence of resistance between countries and between the different antimicrobial agents tested. The highest frequency of resistance was observed for penicillin. For Mannheimia haemolytica...

  11. Antimicrobial resistance among Campylobacter jejuni isolated from raw poultry meat at retail level in Denmark

    DEFF Research Database (Denmark)

    Andersen, S. R.; Saadbye, P.; Shukri, Naseer Mahmoud;

    2006-01-01

    Campylobacter jejuni isolated from raw poultry meat collected at retail shops in Denmark in the period 1996-2003 were tested for susceptibility to seven antimicrobial agents. The food samples consisted of raw chicken meat and other raw poultry meat of domestic or imported origin. The highest levels...... of resistance among C. jejuni were observed for tetracycline, nalidixic acid and ciprofloxacin, whereas macrolide resistance was rarely detected. C. jejuni originating from other poultry meat (mainly duck and turkey meat) exhibited the highest occurrences of antimicrobial resistance monitored; approximately one...... third of the isolates were tetracycline resistant (N=100). Among chicken meat isolates, the occurrence of tetracycline resistance was significantly higher (P chicken meat (N=88) than in C. jejuni from Danish chicken meat (N=367). The same tendency was observed...

  12. Transgenic Cotton and Disease Resistance Genes

    Institute of Scientific and Technical Information of China (English)

    RAJASEKARAN Kanniah

    2008-01-01

    @@ Success in conventional breeding for resistance to mycotoxin-producing or other phytopathogenic fungi is dependent on the availability of resistance gene(s) in the germplasm.Even when it is available,breeding for disease-resistant crops is very time consuming,especially in perennial crops such as tree nut crops,and does not lend itself ready to combat the evolution of new virulent fungal races.

  13. Characterization of Toxin Genes and Antimicrobial Susceptibility of Staphylococcus aureus Isolates in Fishery Products in Iran

    Science.gov (United States)

    Arfatahery, Noushin; Davoodabadi, Abolfazl; Abedimohtasab, Taranehpeimaneh

    2016-01-01

    Staphylococcus aureus is one of the most common causes of seafood-borne diseases worldwide, which are attributable to the contamination of food by preformed enterotoxins. In this study, a total of 206 (34.3%) Staphylococcus aureus strains were obtained from 600 fish and shrimp samples and were tested for their antimicrobial susceptibility. We assessed the prevalence of the genes responsible for the staphylococcal enterotoxins (SEA, SEB) and toxic shock syndrome toxin 1 (TSST-1) genes. The results indicated that 34% of aqua food samples were contaminated with S. aureus, and 23.8% of these isolates were mec-A-positive. Sixty-four percent of the strains isolated from contaminated seafood was enterotoxigenic S. aureus, and 28.2% of SEs were MRSA-positive. The most prevalent genotype was characterized by the presence of the sea gene (45.2%), followed by the seb gene (18.5%), and the tst gene encoding TSST-1 was found in eight strains (3.9%). Of the 206 S. aureus isolates, 189 strains (84.9%) were resistant to at least one antibiotic. Given the frequent outbreaks of enterotoxigenic MRSA, it is necessary to make revisions to mandatory programmes to facilitate improved hygiene practices during fishing, aquaculture, processing, and sales to prevent the contamination of fishery products in Iran.

  14. Detection of antibiotic-resistant bacteria endowed with antimicrobial activity from a freshwater lake and their phylogenetic affiliation

    Science.gov (United States)

    Zothanpuia; Passari, Ajit K.; Gupta, Vijai K.

    2016-01-01

    Antimicrobial resistance poses a serious challenge to global public health. In this study, fifty bacterial strains were isolated from the sediments of a freshwater lake and were screened for antibiotic resistance. Out of fifty isolates, thirty-three isolates showed resistance against at least two of the selected antibiotics. Analysis of 16S rDNA sequencing revealed that the isolates belonged to ten different genera, namely Staphylococcus(n = 8), Bacillus(n = 7), Lysinibacillus(n = 4), Achromobacter(n=3), bacterium(n = 3), Methylobacterium(n = 2), Bosea(n = 2), Aneurinibacillus(n = 2), Azospirillum(n = 1), Novosphingobium(n = 1). Enterobacterial repetitive intergenic consensus (ERIC) and BOX-PCR markers were used to study the genetic relatedness among the antibiotic resistant isolates. Further, the isolates were screened for their antimicrobial activity against bacterial pathogens viz., Staphylococcus aureus(MTCC-96), Pseudomonas aeruginosa(MTCC-2453) and Escherichia coli(MTCC-739), and pathogenic fungi viz., Fusarium proliferatum (MTCC-286), Fusarium oxysporum (CABI-293942) and Fusarium oxy. ciceri (MTCC-2791). In addition, biosynthetic genes (polyketide synthase II (PKS-II) and non-ribosomal peptide synthetase (NRPS)) were detected in six and seven isolates, respectively. This is the first report for the multifunctional analysis of the bacterial isolates from a wetland with biosynthetic potential, which could serve as potential source of useful biologically active metabolites. PMID:27330861

  15. Antimicrobial resistance characteristics and fitness of Gram negative faecal bacteria from volunteers treated with minocycline or amoxicillin.

    Directory of Open Access Journals (Sweden)

    Miranda eKirchner

    2014-12-01

    Full Text Available A yearlong study was performed to examine the effect of antibiotic administration on the bacterial gut flora. Gram-negative facultative anaerobic bacteria were recovered from the faeces of healthy adult volunteers administered amoxicillin, minocycline or placebo, and changes determined in antimicrobial resistance (AMR gene carriage. Seventy percent of the 1039 facultative anaerobic isolates recovered were identified by MALDI-TOF as Escherichia coli. A microarray used to determine virulence and resistance gene carriage demonstrated that AMR genes were widespread in all administration groups, with the most common resistance genes being blaTEM, dfr, strB, tet(A and tet(B. Following amoxicillin administration, an increase in the proportion of amoxicillin resistant E. coli and a three-fold increase in the levels of blaTEM gene carriage was observed, an effect not observed in the other two treatment groups. Detection of virulence genes, including stx1A, indicated not all E. coli were innocuous commensals. Approximately 150 E. coli collected from 6 participants were selected for pulse field gel electrophoresis (PFGE, and a subset used for characterisation of plasmids and Phenotypic Microarrays (PM. PFGE indicated some E. coli clones had persisted in volunteers for up to 1 year, while others were transient. Although there were no unique characteristics associated with plasmids from persistent or transient isolates, PM assays showed transient isolates had greater adaptability to a range of antiseptic biocides and tetracycline; characteristics which were lost in some, but not all persistent isolates. This study indicates healthy individuals carry bacteria harbouring resistance to a variety of antibiotics and biocides in their intestinal tract. Antibiotic administration can have a temporary effect of selecting bacteria, showing co-resistance to multiple antibiotics, some of which can persist within the gut for up to 1 year.

  16. Understanding the contribution of environmental factors in the spread of antimicrobial resistance.

    Science.gov (United States)

    Fletcher, Stephanie

    2015-07-01

    The overuse and abuse of antibiotics have contributed to the global epidemic of antibiotic resistance. Current evidence suggests that widespread dependency on antibiotics and complex interactions between human health, animal husbandry and veterinary medicine, have contributed to the propagation and spread of resistant organisms. The lack of information on pathogens of major public health importance, limited surveillance, and paucity of standards for a harmonised and coordinated approach, further complicates the issue. Despite the widespread nature of antimicrobial resistance, limited focus has been placed on the role of environmental factors in propagating resistance. There are limited studies that examine the role of the environment, specifically water, sanitation and hygiene factors that contribute to the development of resistant pathogens. Understanding these elements is necessary to identify any modifiable interactions to reduce or interrupt the spread of resistance from the environment into clinical settings. This paper discusses some environmental issues that contribute to antimicrobial resistance, including soil related factors, animal husbandry and waste management, potable and wastewater, and food safety, with examples drawn mainly from the Asian region. The discussion concludes that some of the common issues are often overlooked and whilst there are numerous opportunities for environmental factors to contribute to the growing burden of antimicrobial resistance, a renewed focus on innovative and traditional environmental approaches is needed to tackle the problem. PMID:25921603

  17. A trend analysis of antimicrobial resistance in commensal Escherichia coli from several livestock species in Belgium (2011-2014)

    OpenAIRE

    Hanon, Jean-Baptiste; Jaspers, Stijn; Butaye, Patrick; Wattiau, Pierre; Méroc, Estelle; Aerts, Marc; Imberechts, Hein; Vermeersch, Katie; Van der Stede, Yves

    2015-01-01

    A temporal trend analysis was performed on antimicrobial resistance data collected over 4 consecutive years (2011-2014) in the official Belgian antimicrobial resistance monitoring programme. Commensal Escherichia coli strains were isolated from faecal samples of four livestock categories (veal calves, young beef cattle, broiler chickens and slaughter pigs) and the trends of resistance profiles were analysed. The resistance prevalence remained high (>50%) during the study period for ampicillin...

  18. Clinical Impact of Antimicrobial Resistance in European Hospitals : Excess Mortality and Length of Hospital Stay Related to Methicillin-Resistant Staphylococcus aureus Bloodstream Infections

    NARCIS (Netherlands)

    de Kraker, Marlieke E. A.; Wolkewitz, Martin; Davey, Peter G.; Grundmann, Hajo

    2011-01-01

    Antimicrobial resistance is threatening the successful management of nosocomial infections worldwide. Despite the therapeutic limitations imposed by methicillin-resistant Staphylococcus aureus (MRSA), its clinical impact is still debated. The objective of this study was to estimate the excess mortal

  19. Bordetella pertussis lipid A glucosamine modification confers resistance to cationic antimicrobial peptides and increases resistance to outer membrane perturbation.

    Science.gov (United States)

    Shah, Nita R; Hancock, Robert E W; Fernandez, Rachel C

    2014-08-01

    Bordetella pertussis, the causative agent of whooping cough, has many strategies for evading the human immune system. Lipopolysaccharide (LPS) is an important Gram-negative bacterial surface structure that activates the immune system via Toll-like receptor 4 and enables susceptibility to cationic antimicrobial peptides (CAMPs). We show modification of the lipid A region of LPS with glucosamine increased resistance to numerous CAMPs, including LL-37. Furthermore, we demonstrate that this glucosamine modification increased resistance to outer membrane perturbation.

  20. MOLECULAR-PHYLOGENETIC CHARACTERIZATION AND ANTIMICROBIAL RESISTANCE OF Escherichia coli ISOLATED FROM GOATS WITH DIARRHEA

    Directory of Open Access Journals (Sweden)

    Rodrigo Almeida Guimarães

    2015-10-01

    Full Text Available Neonatal diarrhea determines significant changes in feed conversion, causing productivity loss in caprine herds. The antimicrobial resistance in bacteria is characterized as an important public health issue; therefore, Escherichia coli may be characterized as an important pathogen due to expressing virulence mechanisms responsible for significant clinical conditions in humans and animals. The present study evaluated the presence of E. coli among 117 caprine fecal samples and analyzed the isolates for antimicrobial resistance. Suggestive colonies were submitted to biochemical screening followed by genotypic group determination and phylogenetic analysis; further, the samples were submitted to antimicrobials susceptibility test. E. coli, Salmonella spp, Shigella sonnei and Enterobacter aerogenes were identified. E. coli isolates were phylogenetically classified as B2 (9/39, D (19/39, B1 (7/39 e A (4/29 groups. The analysis of the isolates also revealed the presence of K99 (04/39 and Stx (02/39 virulence factors. Antimicrobial susceptibility test revealed sensitive isolates to Chloramphenicol, Streptomycin, Amoxicillin and Ciprofloxacin, being all resistant to Lincomycin, Vancomycin and Penicillin. The results support the need of establishing restricted protocols for antimicrobial use, a fundamental procedure for health improvement in Brazilian caprine herds.

  1. Prevalence, Molecular Characterization, and Antimicrobial Susceptibility of Methicillin-Resistant Staphylococcus aureus Isolated from Milk and Dairy Products.

    Science.gov (United States)

    Al-Ashmawy, Maha Abdou; Sallam, Khalid Ibrahim; Abd-Elghany, Samir Mohammed; Elhadidy, Mohamed; Tamura, Tomohiro

    2016-03-01

    The present work was undertaken to study the prevalence, molecular characterization, virulence factors, and antimicrobial susceptibility of methicillin-resistant Staphylococcus aureus (MRSA) in raw milk and dairy products in Mansoura City, Egypt. MRSA was detected in 53% (106/200) among all milk and dairy products with prevalence rates of 75%, 65%, 40%, 50%, and 35% in raw milk, Damietta cheese, Kareish cheese, ice cream, and yogurt samples, respectively. The mean S. aureus counts were 3.49, 3.71, 2.93, 3.40, and 3.23 log10 colony-forming units (CFU)/g among tested raw milk, Damietta cheese, Kareish cheese, ice cream and yogurt, respectively, with an overall count of 3.41 log10 CFU/g. Interestingly, all recovered S. aureus isolates were genetically verified as MRSA strains by molecular detection of the mecA gene. Furthermore, genes encoding α-hemolysin (hla) and staphylococcal enterotoxins (sea, seb, sec) were detected in all isolates. The antimicrobial susceptibility pattern of recovered MRSA isolates against 13 tested antimicrobials revealed that the least effective drugs were penicillin G, cloxacillin, tetracycline, and amoxicillin with bacterial resistance percentages of 87.9%, 75.9%, 65.2%, and 55.6%, respectively. These findings suggested that milk and dairy products represent a potential infection risk threat of multidrug-resistant and toxigenic S. aureus in Egypt due to neglected hygienic practices during production, retail, or storage stages. These findings highlighted the crucial importance of applying more restrictive hygienic measures in dairy production in Egypt for food safety. PMID:26836943

  2. The co-selection of fluoroquinolone resistance genes in the gut flora of Vietnamese children.

    Directory of Open Access Journals (Sweden)

    Le Thi Minh Vien

    Full Text Available Antimicrobial consumption is one of the major contributing factors facilitating the development and maintenance of bacteria exhibiting antimicrobial resistance. Plasmid-mediated quinolone resistance (PMQR genes, such as the qnr family, can be horizontally transferred and contribute to reduced susceptibility to fluoroquinolones. We performed an observational study, investigating the copy number of PMQR after antimicrobial therapy. We enrolled 300 children resident in Ho Chi Minh City receiving antimicrobial therapy for acute respiratory tract infections (ARIs. Rectal swabs were taken on enrollment and seven days subsequently, counts for Enterobacteriaceae were performed and qnrA, qnrB and qnrS were quantified by using real-time PCR on metagenomic stool DNA. On enrollment, we found no association between age, gender or location of the participants and the prevalence of qnrA, qnrB or qnrS. Yet, all three loci demonstrated a proportional increase in the number of samples testing positive between day 0 and day 7. Furthermore, qnrB demonstrated a significant increase in copy number between paired samples (p<0.001; Wilcoxon rank-sum, associated with non-fluoroquinolone combination antimicrobial therapy. To our knowledge, this is the first study describing an association between the use of non-fluoroquinolone antimicrobials and the increasing relative prevalence and quantity of qnr genes. Our work outlines a potential mechanism for the selection and maintenance of PMQR genes and predicts a strong effect of co-selection of these resistance determinants through the use of unrelated and potentially unnecessary antimicrobial regimes.

  3. Trends in the resistance to antimicrobial agents of Streptococcus suis isolates from Denmark and Sweden.

    Science.gov (United States)

    Aarestrup, F M; Rasmussen, S R; Artursson, K; Jensen, N E

    1998-08-28

    This study was conducted to determine the MIC values of historical and contemporary Streptoccocus suis (serotypes 2 and 7) from Denmark and S. suis (serotype 2) from Sweden. A total of 52 isolates originating from 1967 through 1981 and 156 isolates from 1992 through 1997 in Denmark and 13 isolates from Sweden were examined for their MICs against 20 different antimicrobial agents. Most antimicrobials were active against most isolates. A frequent occurrence of resistance to sulphamethoxazole was observed, with most resistance among historic isolates of serotype 7 and least resistance among isolates from Sweden. A large number of the isolates was resistant to macrolides. However, all historic serotype 2 isolates from Denmark were susceptible, whereas 20.4% of the contemporary isolates were resistant. Among serotype 7 isolates 23.3% of the historic isolates were resistant to macrolides, whereas resistance was found in 44.8% of the contemporary isolates. All isolates from Sweden were susceptible to macrolides. Time-associated frequency of resistance to tetracycline was also found. Only a single historic isolate of serotype 2 was resistant to tetracycline, whereas 43.9% of the contemporary serotype 2 isolates and 15.5% of the contemporary serotype 7 isolates were resistant. Only one (7.7%) of the isolates from Sweden was resistant. The differences in resistance between historic and contemporary isolates from Denmark were statistically significant. This study demonstrated a significant serotype-associated difference in the susceptibility to macrolides and tetracycline and demonstrated that an increase in resistance among S. suis isolates has taken place during the last 15 years to the two most commonly used antimicrobial agents (tylosin and tetracycline) in pig production in Denmark. PMID:9810623

  4. Bacterial resistance to ciprofloxacin in Greece: results from the National Electronic Surveillance System. Greek Network for the Surveillance of Antimicrobial Resistance.

    OpenAIRE

    Vatopoulos, A. C.; Kalapothaki, V.; Legakis, N. J.

    1999-01-01

    According to 1997 susceptibility data from the National Electronic System for the Surveillance of Antimicrobial Resistance, Greece has high rates of ciprofloxacin resistance. For most species, the frequency of ciprofloxacin-resistant isolates (from highest to lowest, by patient setting) was as follows: intensive care unit > surgical > medical > outpatient. Most ciprofloxacin-resistant strains were multidrug resistant.

  5. Nanostructured mesoporous silica: new perspectives for fighting antimicrobial resistance

    Energy Technology Data Exchange (ETDEWEB)

    Voicu, Georgeta; Dogaru, Ionuţ; Meliţă, Daniela; Meştercă, Raluca; Spirescu, Vera; Stan, Eliza; Tote, Eliza [Politehnica University of Bucharest, Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science (Romania); Mogoantă, Laurenţiu [University of Medicine and Pharmacy of Craiova, Research Center for Microscopic Morphology and Immunology (Romania); Mogoşanu, George Dan [University of Medicine and Pharmacy of Craiova, Department of Pharmacognosy & Phytotherapy, Faculty of Pharmacy (Romania); Grumezescu, Alexandru Mihai, E-mail: grumezescu@yahoo.com [Politehnica University of Bucharest, Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science (Romania); Truşcă, Roxana [Metav SA-CD S.A. (Romania); Vasile, Eugeniu [Politehnica University of Bucharest, Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science (Romania); Iordache, Florin [Institute of Cellular Biology and Pathology of Romanian Academy, “Nicolae Simionescu”, Department of Fetal and Adult Stem Cell Therapy (Romania); Chifiriuc, Mariana-Carmen [University of Bucharest, Microbiology Department, Faculty of Biology (Romania); Holban, Alina Maria [Politehnica University of Bucharest, Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science (Romania)

    2015-05-15

    This paper investigates the antimicrobial potential of nanostructured mesoporous silica (NMS) functionalized with essential oils (EOs) and antibiotics (ATBs). The NMS networks were obtained by the basic procedure from cetyltrimethylammonium bromide and tetraethyl orthosilicate in the form of granules with diameters ranging from 100 to 300 nm with an average pore diameter of 2.2 nm, as confirmed by the BET–TEM analyses. The Salvia officinalis (SO) and Coriandrum sativum (CS) EOs and the streptomycin and neomycin ATBs were loaded in the NMS pores. TG analysis was performed in order to estimate the amount of the entrapped volatile EOs. The results of the biological analyses revealed that NMS/SO and NMS/CS exhibited a very good antimicrobial activity to an extent comparable or even superior to the one triggered by ATB, and a good in vitro and in vivo biocompatibility. Due to their regular pores, high biocompatibility, antimicrobial activity, and capacity to stabilize the volatile EOs, the obtained NMS can be used as an efficient drug delivery system for further biomedical applications.

  6. Nanostructured mesoporous silica: new perspectives for fighting antimicrobial resistance

    International Nuclear Information System (INIS)

    This paper investigates the antimicrobial potential of nanostructured mesoporous silica (NMS) functionalized with essential oils (EOs) and antibiotics (ATBs). The NMS networks were obtained by the basic procedure from cetyltrimethylammonium bromide and tetraethyl orthosilicate in the form of granules with diameters ranging from 100 to 300 nm with an average pore diameter of 2.2 nm, as confirmed by the BET–TEM analyses. The Salvia officinalis (SO) and Coriandrum sativum (CS) EOs and the streptomycin and neomycin ATBs were loaded in the NMS pores. TG analysis was performed in order to estimate the amount of the entrapped volatile EOs. The results of the biological analyses revealed that NMS/SO and NMS/CS exhibited a very good antimicrobial activity to an extent comparable or even superior to the one triggered by ATB, and a good in vitro and in vivo biocompatibility. Due to their regular pores, high biocompatibility, antimicrobial activity, and capacity to stabilize the volatile EOs, the obtained NMS can be used as an efficient drug delivery system for further biomedical applications

  7. The tetracycline resistance determinant Tet 39 and the sulphonamide resistance gene sulII are common among resistant Acinetobacter spp. isolated from integrated fish farms in Thailand

    DEFF Research Database (Denmark)

    Agersø, Yvonne; Petersen, Andreas

    2007-01-01

    sulfamethoxazole-resistant contained sulII (96%; 129/134) and/or sulI (14%; 19/134) (as part of class I integrons). sulII and tet(39) were located on plasmids differing in size in the isolates tested. Conclusions: The study shows tet(39) and sulII to be common resistance genes among clonally distinct Acinetobacter...... spp. from integrated fish farms and these bacteria may constitute reservoirs of resistance genes that may increase owing to a selective pressure caused by the use of antimicrobials in the overlaying animal production.......Objectives: To determine the genetic basis for tetracycline and sulphonamide resistance and the prevalence of class I and II integrons in oxytetracycline-resistant Acinetobacter spp. from integrated fish farms in Thailand. Methods: A total of 222 isolates were screened for tetracycline resistance...

  8. Evaluation of short synthetic antimicrobial peptides for treatment of drug-resistant and intracellular Staphylococcus aureus.

    Science.gov (United States)

    Mohamed, Mohamed F; Abdelkhalek, Ahmed; Seleem, Mohamed N

    2016-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) infections present a serious challenge because of the emergence of resistance to numerous conventional antibiotics. Due to their unique mode of action, antimicrobial peptides are novel alternatives to traditional antibiotics for tackling the issue of bacterial multidrug resistance. Herein, we investigated the antibacterial activity of two short novel peptides (WR12, a 12 residue peptide composed exclusively of arginine and tryptophan, and D-IK8, an eight residue β-sheet peptide) against multidrug resistant staphylococci. In vitro, both peptides exhibited good antibacterial activity against MRSA, vancomycin-resistant S. aureus, linezolid-resistant S. aureus, and methicillin-resistant S. epidermidis. WR12 and D-IK8 were able to eradicate persisters, MRSA in stationary growth phase, and showed significant clearance of intracellular MRSA in comparison to both vancomycin and linezolid. In vivo, topical WR12 and D-IK8 significantly reduced both the bacterial load and the levels of the pro-inflammatory cytokines including tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in MRSA-infected skin lesions. Moreover, both peptides disrupted established in vitro biofilms of S. aureus and S. epidermidis significantly more so than traditional antimicrobials tested. Taken together, these results support the potential of WR12 and D-IK8 to be used as a topical antimicrobial agent for the treatment of staphylococcal skin infections. PMID:27405275

  9. Antimicrobial Resistance, Extended-Spectrum β-Lactamase Productivity, and Class 1 Integrons in Escherichia coli from Healthy Swine.

    Science.gov (United States)

    Changkaew, Kanjana; Intarapuk, Apiradee; Utrarachkij, Fuangfa; Nakajima, Chie; Suthienkul, Orasa; Suzuki, Yasuhiko

    2015-08-01

    Administration of antimicrobials to food-producing animals increases the risk of higher antimicrobial resistance in the normal intestinal flora of these animals. The present cross-sectional study was conducted to investigate antimicrobial susceptibility and extended-spectrum β-lactamase (ESBL)-producing strains and to characterize class 1 integrons in Escherichia coli in healthy swine in Thailand. All 122 of the tested isolates had drug-resistant phenotypes. High resistance was found to ampicillin (98.4% of isolates), chloramphenicol (95.9%), gentamicin (78.7%), streptomycin (77.9%), tetracycline (74.6%), and cefotaxime (72.1%). Fifty-four (44.3%) of the E. coli isolates were confirmed as ESBL-producing strains. Among them, blaCTX-M (45 isolates) and blaTEM (41 isolates) were detected. Of the blaCTX-M-positive E. coli isolates, 37 carried the blaCTX-M-1 cluster, 12 carried the blaCTX-M-9 cluster, and 5 carried both clusters. Sequence analysis revealed blaTEM-1, blaTEM-135, and blaTEM-175 in 38, 2, and 1 isolate, respectively. Eighty-seven (71%) of the 122isolates carried class 1 integrons, and eight distinct drug-resistance gene cassettes with seven different integron profiles were identified in 43 of these isolates. Gene cassettes were associated with resistance to aminoglycosides (aadA1, aadA2, aadA22, or aadA23), trimethoprim (dfrA5, dfrA12, or dfrA17), and lincosamide (linF). Genes encoding β-lactamases were not found in class 1 integrons. This study is the first to report ESBL-producing E. coli with a class 1 integron carrying the linF gene cassette in swine in Thailand. Our findings confirm that swine can be a reservoir of ESBL-producing E. coli harboring class 1 integrons, which may become a potential health risk if these integrons are transmitted to humans. Intensive analyses of animal, human, and environmental isolates are needed to control the spread of ESBL-producing E. coli strains.

  10. Antimicrobial Resistance, Extended-Spectrum β-Lactamase Productivity, and Class 1 Integrons in Escherichia coli from Healthy Swine.

    Science.gov (United States)

    Changkaew, Kanjana; Intarapuk, Apiradee; Utrarachkij, Fuangfa; Nakajima, Chie; Suthienkul, Orasa; Suzuki, Yasuhiko

    2015-08-01

    Administration of antimicrobials to food-producing animals increases the risk of higher antimicrobial resistance in the normal intestinal flora of these animals. The present cross-sectional study was conducted to investigate antimicrobial susceptibility and extended-spectrum β-lactamase (ESBL)-producing strains and to characterize class 1 integrons in Escherichia coli in healthy swine in Thailand. All 122 of the tested isolates had drug-resistant phenotypes. High resistance was found to ampicillin (98.4% of isolates), chloramphenicol (95.9%), gentamicin (78.7%), streptomycin (77.9%), tetracycline (74.6%), and cefotaxime (72.1%). Fifty-four (44.3%) of the E. coli isolates were confirmed as ESBL-producing strains. Among them, blaCTX-M (45 isolates) and blaTEM (41 isolates) were detected. Of the blaCTX-M-positive E. coli isolates, 37 carried the blaCTX-M-1 cluster, 12 carried the blaCTX-M-9 cluster, and 5 carried both clusters. Sequence analysis revealed blaTEM-1, blaTEM-135, and blaTEM-175 in 38, 2, and 1 isolate, respectively. Eighty-seven (71%) of the 122isolates carried class 1 integrons, and eight distinct drug-resistance gene cassettes with seven different integron profiles were identified in 43 of these isolates. Gene cassettes were associated with resistance to aminoglycosides (aadA1, aadA2, aadA22, or aadA23), trimethoprim (dfrA5, dfrA12, or dfrA17), and lincosamide (linF). Genes encoding β-lactamases were not found in class 1 integrons. This study is the first to report ESBL-producing E. coli with a class 1 integron carrying the linF gene cassette in swine in Thailand. Our findings confirm that swine can be a reservoir of ESBL-producing E. coli harboring class 1 integrons, which may become a potential health risk if these integrons are transmitted to humans. Intensive analyses of animal, human, and environmental isolates are needed to control the spread of ESBL-producing E. coli strains. PMID:26219356

  11. 新生儿科产超广谱β-内酰胺酶肺炎克雷伯菌的耐药性分析及基因分型%Antimicrobial resistance and gene typing of ESBLs Klebsiella pneumoniae for newborn

    Institute of Scientific and Technical Information of China (English)

    陈汉斌

    2011-01-01

    Objective:To investigate antimicrobial resistance and genotypes of ESBLs-producing Klebsiella pneumoniae from newborn department in our hospital. Methods: Klebsiella pneumoniae were collected from newborn department,ESBLs preliminary screen and phenotype confirmatory tests were carried out according to the NCCLS guidelines; Antimicrobial susceptibility tests were determined by Kirby-Bauer test; gene types of ESBLs were performed with PCR. Results;The detection rate of ESBLs-producing Klebsiella pneumoniae was 71. 11% (64/90). ESBLs-producing Klebsiella pneumoniae were sensitive to the combination of the third generation cephalosporins with lactamases inhibitor and carbapenems. The detection rate of genes of SHV, TEM 、 CTX-M-1 was 71.64%、37.50%、49.79%、37.71% and 12.28% of ESBL-producing Klebsiella pneumoniae carried two or three genes respectively. Conclusion;Antimicrobial resistance of Klebsiella pneumoniae is serious,the main gene types are SHV and CTX-M-1.%目的:了解本院新生儿科送检标本中,分离的产超广谱β-内酰胺酶( ESBLs)肺炎克雷伯菌的耐药性及基因分型.方法:收集本院新生儿科送检标本中分离的肺炎克雷伯菌,采用双纸片协同试验的方法进行ESBLs初筛及表型确证试验;K-B纸片扩散法进行抗菌药物敏感性试验;聚合酶链反应(PCR)法分析ESBLs的基因分型.结果:产ESBLs肺炎克雷伯菌的检出率为71.11% (64/90).产ESBLs肺炎克雷伯菌对第3代头孢菌素与β-内酰胺酶抑制剂合剂、碳青霉烯类抗生素较敏感.ESBLs的基因型分析结果显示,产ESBLs肺炎克雷伯菌中SHV、TEM、CTX-M-1基因扩增阳性率分别为71.64%、37.50%、49.79%,同时携带2种或3种耐药基因的菌株分别占37.71%和12.28%.结论:新生儿科产ESBLs肺炎克雷伯菌的耐药现象严重,ESBLs基因型以SHV、CTX-M-1为主.

  12. THE STUDY OF RESISTENCE OF STAPHYLOCOCCUS AUREUS STRAINS TO ANTIMICROBIALS

    Directory of Open Access Journals (Sweden)

    Nazarchuk GG

    2012-12-01

    Full Text Available In the research work the results of the study of resistance forming to antibiotics, antiseptics and decametoxine composition with modified polysaccharides in S.aureus strains are presented. The development of resistance to penicillins, cephalosporins, glycopeptides, macrolides is shown. Slow forming of resistance to decasan and decametoxine composition with carboxymethylamylum, oxyethylcellulose was determined.

  13. Investigation of antimicrobial resistance in Escherichia coli and enterococci isolated from Tibetan pigs.

    Directory of Open Access Journals (Sweden)

    Peng Li

    Full Text Available OBJECTIVES: This study investigated the antimicrobial resistance of Escherichia coli and enterococci isolated from free-ranging Tibetan pigs in Tibet, China, and analyzed the influence of free-ranging husbandry on antimicrobial resistance. METHODS: A total of 232 fecal samples were collected from Tibetan pigs, and the disk diffusion method was used to examine their antimicrobial resistance. Broth microdilution and agar dilution methods were used to determine minimum inhibitory concentrations for antimicrobial agents for which disks were not commercially available. RESULTS: A total of 129 E. coli isolates and 84 Enterococcus isolates were recovered from the fecal samples. All E. coli isolates were susceptible to amoxicillin/clavulanic acid, and 40.4% were resistant to tetracycline. A small number of isolates were resistant to florfenicol (27.9%, ampicillin (27.9%, sulfamethoxazole/trimethoprim (19.4%, nalidixic acid (19.4%, streptomycin (16.2% and ceftiofur (10.9%, and very low resistance rates to ciprofloxacin (7.8%, gentamicin (6.9%, and spectinomycin (2.3% were observed in E. coli. All Enterococcus isolates, including E. faecium, E. faecalis, E. hirae, and E. mundtii, were susceptible to amoxicillin/clavulanic acid and vancomycin, but showed high frequencies of resistance to oxacillin (92.8%, clindamycin (82.1%, tetracycline (64.3%, and erythromycin (48.8%. Resistance rates to florfenicol (17.9%, penicillin (6.0%, ciprofloxacin (3.6%, levofloxacin (1.2%, and ampicillin (1.2% were low. Only one high-level streptomycin resistant E. faecium isolate and one high-level gentamicin resistant E. faecium isolate were observed. Approximately 20% and 70% of E. coli and Enterococcus isolates, respectively, were defined as multidrug-resistant. CONCLUSIONS: In this study, E. coli and Enterococcus isolated from free-ranging Tibetan pigs showed relatively lower resistance rates than those in other areas of China, where more intensive farming practices are

  14. Klebsiella pneumoniae: development of a mixed population of carbapenem and tigecycline resistance during antimicrobial therapy in a kidney transplant patient.

    Science.gov (United States)

    Rodríguez-Avial, C; Rodríguez-Avial, I; Merino, P; Picazo, J J

    2012-01-01

    Nine isolates of Klebsiella pneumoniae were isolated from a renal transplant patient suffering from recurrent urosepsis over a period of 4 months. Imipenem resistance was detected after imipenem-ertapenem therapy. When treatment was switched to tigecycline the K. pneumoniae developed resistance to tigecycline (MIC = 8 mg/L). The nine isolates were tested by determination of agar dilution MICs, phenotypic carbapenemase, extended-spectrum beta-lactamases and metallo-beta-lactamase (MBL) testing and pulsed-field gel electrophoresis. Polymerase chain reaction and sequencing analysis were employed for identification of bla genes and mapping of the integron carrying the MBL gene. The nine isolates were clonally related and all produced the SHV-12 enzyme. Five MBL-producing isolates showed imipenem MICs ranging from 2 to 64 mg/L and all were detected by testing with imipenem and EDTA. The five isolates harboured the bla(VIM-1) gene. Three isolates showed increased tigecycline MICs (4-8 mg/L). Serial blood cultures obtained on the same day resulted in a VIM-positive/tigecycline-susceptible and a VIM-negative/tigecycline-resistant K. pneumoniae isolate. No isolate developed concurrent imipenem and tigecycline resistance. The patient had a persistent urinary tract infection and recurrent bacteraemia caused by a mixed population of Klebesiella pneumoniae isolates adapting to the selective pressure of antimicrobial therapy at the time. The present study is a worrisome example of what could happen when an immunocompromised host is subjected to the pressures of antimicrobial therapy. In addition, we report the first treatment-emergent MIC increase of tigecycline from 0.5 to 8 mg/L in K. pneumoniae. PMID:21722259

  15. Antimicrobial resistance in Salmonella enterica subsp. enterica serovar typhimurium from humans and production animals

    DEFF Research Database (Denmark)

    Seyfarth, Anne Mette; Wegener, Henrik Caspar; FrimodtMoller, N.

    1997-01-01

    to the State Serum Institute during August 1993 (228 isolates). The animal strains were isolated from clinical or subclinical infections in cattle (48 isolates), pigs (99 isolates) or poultry (98 isolates), all from 1993. All strains were tested against 22 different antimicrobial agents used in both human...... and veterinary medicine with the tablet diffusion method. Strains were also phage-typed and the plasmid content determined in all resistant strains. Ribotyping was performed on selected strains. Of 228 human isolates tested, 19.3% of the strains were resistant to one or more antimicrobial agent compared with 10...... infections contracted outside Denmark, most often in southern Europe or south-east Asia. Resistance in human strains was most common against tetracycline (13%), ampicillin (12%), sulphonamide (12%), streptomycin (10%) and chloramphenicol (8%). The resistance pattern differed somewhat in animal isolates...

  16. Isolation and characterization of antimicrobial compounds in plant extracts against multidrug-resistant Acinetobacter baumannii.

    Directory of Open Access Journals (Sweden)

    Yoko Miyasaki

    Full Text Available The number of fully active antibiotic options that treat nosocomial infections due to multidrug-resistant Acinetobacter baumannii (A. baumannii is extremely limited. Magnolia officinalis, Mahonia bealei, Rabdosia rubescens, Rosa rugosa, Rubus chingii, Scutellaria baicalensis, and Terminalia chebula plant extracts were previously shown to have growth inhibitory activity against a multidrug-resistant clinical strain of A. baumannii. In this study, the compounds responsible for their antimicrobial activity were identified by fractionating each plant extract using high performance liquid chromatography, and determining the antimicrobial activity of each fraction against A. baumannii. The chemical structures of the fractions inhibiting >40% of the bacterial growth were elucidated by liquid chromatography/mass spectrometry analysis and nuclear magnetic resonance spectroscopy. The six most active compounds were identified as: ellagic acid in Rosa rugosa; norwogonin in Scutellaria baicalensis; and chebulagic acid, chebulinic acid, corilagin, and terchebulin in Terminalia chebula. The most potent compound was identified as norwogonin with a minimum inhibitory concentration of 128 µg/mL, and minimum bactericidal concentration of 256 µg/mL against clinically relevant strains of A. baumannii. Combination studies of norwogonin with ten anti-Gram negative bacterial agents demonstrated that norwogonin did not enhance the antimicrobial activity of the synthetic antibiotics chosen for this study. In conclusion, of all identified antimicrobial compounds, norwogonin was the most potent against multidrug-resistant A. baumannii strains. Further studies are warranted to ascertain the prophylactic and therapeutic potential of norwogonin for infections due to multidrug-resistant A. baumannii.

  17. Isolation and characterization of antimicrobial compounds in plant extracts against multidrug-resistant Acinetobacter baumannii.

    Science.gov (United States)

    Miyasaki, Yoko; Rabenstein, John D; Rhea, Joshua; Crouch, Marie-Laure; Mocek, Ulla M; Kittell, Patricia Emmett; Morgan, Margie A; Nichols, Wesley Stephen; Van Benschoten, M M; Hardy, William David; Liu, George Y

    2013-01-01

    The number of fully active antibiotic options that treat nosocomial infections due to multidrug-resistant Acinetobacter baumannii (A. baumannii) is extremely limited. Magnolia officinalis, Mahonia bealei, Rabdosia rubescens, Rosa rugosa, Rubus chingii, Scutellaria baicalensis, and Terminalia chebula plant extracts were previously shown to have growth inhibitory activity against a multidrug-resistant clinical strain of A. baumannii. In this study, the compounds responsible for their antimicrobial activity were identified by fractionating each plant extract using high performance liquid chromatography, and determining the antimicrobial activity of each fraction against A. baumannii. The chemical structures of the fractions inhibiting >40% of the bacterial growth were elucidated by liquid chromatography/mass spectrometry analysis and nuclear magnetic resonance spectroscopy. The six most active compounds were identified as: ellagic acid in Rosa rugosa; norwogonin in Scutellaria baicalensis; and chebulagic acid, chebulinic acid, corilagin, and terchebulin in Terminalia chebula. The most potent compound was identified as norwogonin with a minimum inhibitory concentration of 128 µg/mL, and minimum bactericidal concentration of 256 µg/mL against clinically relevant strains of A. baumannii. Combination studies of norwogonin with ten anti-Gram negative bacterial agents demonstrated that norwogonin did not enhance the antimicrobial activity of the synthetic antibiotics chosen for this study. In conclusion, of all identified antimicrobial compounds, norwogonin was the most potent against multidrug-resistant A. baumannii strains. Further studies are warranted to ascertain the prophylactic and therapeutic potential of norwogonin for infections due to multidrug-resistant A. baumannii. PMID:23630600

  18. Antimicrobial resistance in Enterococcus spp. isolated from environmental samples in the area of intensive poultry production

    Science.gov (United States)

    In this study, we investigated antimicrobial resistance of Enterococcus spp. from different environmental compartments including litter from two farms, 12 surface and 28 groundwater sites in an area of intensive poultry production and litter application. The enumerated isolates (n=250) were tested ...

  19. PREVALENCE AND ANTIMICROBIAL RESISTANCE ASSESSMENT OF SUBCLINICAL MASTITIS IN MILK SAMPLES FROM SELECTED DAIRY FARMS

    Directory of Open Access Journals (Sweden)

    Murugaiyah Marimuthu

    2014-01-01

    Full Text Available This study was conducted in order to determine the prevalence and bacteriological assessment of subclinical mastitis and antimicrobial resistance of bacterial isolates from dairy cows in different farms around Selangor, Malaysia. A total of 120 milk samples from 3 different farms were randomly collected and tested for subclinical mastitis using California Mastitis Test (CMT, as well as for bacterial culture for isolation, identification and antimicrobial resistance. The most prevalent bacteria was Staphylococcus sp. (55%, followed by Bacillus sp., (21% and Corynebacterium sp., (7%, Yersinia sp. and Neisseria sp. both showed 5% prevalence, other species with prevalence below 5% are Acinetobacter sp., Actinobacillus sp., Vibrio sp., Pseudomonas sp., E.coli, Klebsiella sp. and Chromobacter sp. Selected Staphylococcus sp. showed a mean antimicrobial resistance of 73.3% to Ampicillin, 26.7% to Penicillin, Methicillin and Compound Sulphonamide each, 20% to Oxacillin, Amoxycillin and Cefuroxime, 13.3% to Polymyxin B, Erythromycin, Ceftriaxone and Azithromycin and 6.7% to Streptomycin, Clindamycin, Lincomycin and Tetracycline each. This study indicates the need for urgent and effective control measures to tackle the increase in prevalence of subclinical mastitis and their antimicrobial resistance in the study area.

  20. Spatial scan statistics to assess sampling strategy of antimicrobial resistance monitoring programme

    DEFF Research Database (Denmark)

    Vieira, Antonio; Houe, Hans; Wegener, Henrik Caspar;

    2009-01-01

    sampled by the Danish Integrated Antimicrobial Resistance Monitoring and Research Programme (DANMAP), by identifying spatial Clusters of samples and detecting areas with significantly high or low sampling rates. These analyses were performed for each year and for the total 5-year study period for all...

  1. 76 FR 21907 - Draft Action Plan-A Public Health Action Plan To Combat Antimicrobial Resistance

    Science.gov (United States)

    2011-04-19

    ... the draft, A Public Health Action Plan to Combat Antimicrobial Resistance (76 FR 14402). Written and... electronically to: http://www.regulations.gov . All comments received will be posted publicly without change..., reflected a broad-based consensus of participating Federal agencies, which was reached with individual...

  2. Comparison of antimicrobial resistance determinants among Salmonella, Campylobacter, Escherichia coli, and Enterococcus isolated from Swine

    Science.gov (United States)

    Introduction: The importance of Salmonella, Campylobacter, E.coli, and Enterococcus as carriers of antimicrobial resistance is well known, but limited work has been done to examine the relationship between this phenotypic characteristic and genotypic attributes among strains isolated in similar set...