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Sample records for antimicrobial resistance phenotypes

  1. Associations between Antimicrobial Resistance Phenotypes, Antimicrobial Resistance Genes, and Virulence Genes of Fecal Escherichia coli Isolates from Healthy Grow-Finish Pigs ▿

    OpenAIRE

    Rosengren, Leigh B.; Waldner, Cheryl L.; Reid-Smith, Richard J.

    2009-01-01

    Escherichia coli often carries linked antimicrobial resistance genes on transmissible genetic elements. Through coselection, antimicrobial use may select for unrelated but linked resistance or virulence genes. This study used unconditional statistical associations to investigate the relationships between antimicrobial resistance phenotypes and antimicrobial resistance genes in 151 E. coli isolates from healthy pigs. Phenotypic resistance to each drug was significantly associated with phenotyp...

  2. Antimicrobial resistance patterns of phenotype Extended Spectrum ...

    African Journals Online (AJOL)

    Methods: From July 2013 to January 2014, urine, pus and blood samples were collected from patients suspected to have bacterial infections at Kilimanjaro Christian Medical Centre in Moshi, Tanzania. The isolates were identified based on standard laboratory procedures. Antimicrobial susceptibility tests were carried out ...

  3. 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

    2015-10-30

    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. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  4. Prediction of Phenotypic Antimicrobial Resistance Profiles From Whole Genome Sequences of Non-typhoidal Salmonella enterica.

    Science.gov (United States)

    Neuert, Saskia; Nair, Satheesh; Day, Martin R; Doumith, Michel; Ashton, Philip M; Mellor, Kate C; Jenkins, Claire; Hopkins, Katie L; Woodford, Neil; de Pinna, Elizabeth; Godbole, Gauri; Dallman, Timothy J

    2018-01-01

    Surveillance of antimicrobial resistance (AMR) in non-typhoidal Salmonella enterica (NTS), is essential for monitoring transmission of resistance from the food chain to humans, and for establishing effective treatment protocols. We evaluated the prediction of phenotypic resistance in NTS from genotypic profiles derived from whole genome sequencing (WGS). Genes and chromosomal mutations responsible for phenotypic resistance were sought in WGS data from 3,491 NTS isolates received by Public Health England's Gastrointestinal Bacteria Reference Unit between April 2014 and March 2015. Inferred genotypic AMR profiles were compared with phenotypic susceptibilities determined for fifteen antimicrobials using EUCAST guidelines. Discrepancies between phenotypic and genotypic profiles for one or more antimicrobials were detected for 76 isolates (2.18%) although only 88/52,365 (0.17%) isolate/antimicrobial combinations were discordant. Of the discrepant results, the largest number were associated with streptomycin (67.05%, n = 59). Pan-susceptibility was observed in 2,190 isolates (62.73%). Overall, resistance to tetracyclines was most common (26.27% of isolates, n = 917) followed by sulphonamides (23.72%, n = 828) and ampicillin (21.43%, n = 748). Multidrug resistance (MDR), i.e., resistance to three or more antimicrobial classes, was detected in 848 isolates (24.29%) with resistance to ampicillin, streptomycin, sulphonamides and tetracyclines being the most common MDR profile ( n = 231; 27.24%). For isolates with this profile, all but one were S . Typhimurium and 94.81% ( n = 219) had the resistance determinants bla TEM-1, strA-strB, sul2 and tet (A). Extended-spectrum β-lactamase genes were identified in 41 isolates (1.17%) and multiple mutations in chromosomal genes associated with ciprofloxacin resistance in 82 isolates (2.35%). This study showed that WGS is suitable as a rapid means of determining AMR patterns of NTS for public health surveillance.

  5. Phenotypic and Genotypic Analysis of Antimicrobial Resistance among Listeria monocytogenes Isolated from Australian Food Production Chains

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    Annaleise Wilson

    2018-02-01

    Full Text Available The current global crisis of antimicrobial resistance (AMR among important human bacterial pathogens has been amplified by an increased resistance prevalence. In recent years, a number of studies have reported higher resistance levels among Listeria monocytogenes isolates, which may have implications for treatment of listeriosis infection where resistance to key treatment antimicrobials is noted. This study examined the genotypic and phenotypic AMR patterns of 100 L. monocytogenes isolates originating from food production supplies in Australia and examined this in the context of global population trends. Low levels of resistance were noted to ciprofloxacin (2% and erythromycin (1%; however, no resistance was observed to penicillin G or tetracycline. Resistance to ciprofloxacin was associated with a mutation in the fepR gene in one isolate; however, no genetic basis for resistance in the other isolate was identified. Resistance to erythromycin was correlated with the presence of the ermB resistance gene. Both resistant isolates belonged to clonal complex 1 (CC1, and analysis of these in the context of global CC1 isolates suggested that they were more similar to isolates from India rather than the other CC1 isolates included in this study. This study provides baseline AMR data for L. monocytogenes isolated in Australia, identifies key genetic markers underlying this resistance, and highlights the need for global molecular surveillance of resistance patterns to maintain control over the potential dissemination of AMR isolates.

  6. Phenotypic and Genotypic Analysis of Antimicrobial Resistance among Listeria monocytogenes Isolated from Australian Food Production Chains.

    Science.gov (United States)

    Wilson, Annaleise; Gray, Jessica; Chandry, P Scott; Fox, Edward M

    2018-02-09

    The current global crisis of antimicrobial resistance (AMR) among important human bacterial pathogens has been amplified by an increased resistance prevalence. In recent years, a number of studies have reported higher resistance levels among Listeria monocytogenes isolates, which may have implications for treatment of listeriosis infection where resistance to key treatment antimicrobials is noted. This study examined the genotypic and phenotypic AMR patterns of 100 L. monocytogenes isolates originating from food production supplies in Australia and examined this in the context of global population trends. Low levels of resistance were noted to ciprofloxacin (2%) and erythromycin (1%); however, no resistance was observed to penicillin G or tetracycline. Resistance to ciprofloxacin was associated with a mutation in the fepR gene in one isolate; however, no genetic basis for resistance in the other isolate was identified. Resistance to erythromycin was correlated with the presence of the ermB resistance gene. Both resistant isolates belonged to clonal complex 1 (CC1), and analysis of these in the context of global CC1 isolates suggested that they were more similar to isolates from India rather than the other CC1 isolates included in this study. This study provides baseline AMR data for L. monocytogenes isolated in Australia, identifies key genetic markers underlying this resistance, and highlights the need for global molecular surveillance of resistance patterns to maintain control over the potential dissemination of AMR isolates.

  7. Antimicrobial Resistance

    Science.gov (United States)

    ... least 10 countries (Australia, Austria, Canada, France, Japan, Norway, Slovenia, South Africa, Sweden and the United Kingdom ... plan Global report on surveillance Country situation analysis Policy to combat antimicrobial resistance More on antimicrobial resistance ...

  8. Associations between anti-microbial resistance phenotypes, anti-microbial resistance genotypes and virulence genes of Escherichia coli isolates from Pakistan and China.

    Science.gov (United States)

    Yaqoob, M; Wang, L P; Wang, S; Hussain, S; Memon, J; Kashif, J; Lu, C-P

    2013-10-01

    The objective of this study was to determine the association between phenotypic resistance, genotypic resistance and virulence genes of Escherichia coli isolates in Jiangsu province, China and Punjab province Pakistan. A total of 62 E. coli isolates were characterized for phenotypic resistance, genotypic resistance and virulence factor genes. The anti-microbial resistance phenotype and genotypes in relation to virulence factor genes were assessed by statistical analysis. Of 20 tested virulence genes, twelve were found and eight were not found in any isolates. sitA and TspE4C2 were the most prevalent virulence genes. Of the 13 anti-microbial agents tested, resistance to ampicillin, sulphonamide and tetracycline was the most frequent. All isolates were multiresistant, and 74% were resistant to trimethoprim and sulphamethaxazole. Phenotypically, tetracycline-, cefotaxime- and trimethoprim-resistant isolates had increased virulence factors as compared with susceptible isolates. Genotypically, resistant genes Tem, ctx-M, Tet, Sul 1, dhfr1, Cat2 and flo-R showed the association with the virulence genes. Almost all classes of anti-microbial-resistant genes have a high association with virulence. Resistant isolates have more virulent genes than the susceptible isolates. © 2012 Blackwell Verlag GmbH.

  9. Phenotypic and genotypic characterisation of antimicrobial resistance in faecal bacteria from 30 Giant pandas.

    Science.gov (United States)

    Zhang, An-Yun; Wang, Hong-Ning; Tian, Guo-Bao; Zhang, Yi; Yang, Xin; Xia, Qing-Qing; Tang, Jun-Ni; Zou, Li-Kou

    2009-05-01

    To study the prevalence of antimicrobial resistance in faecal bacteria from Giant pandas in China, 59 isolates were recovered from faecal pats of 30 Giant pandas. Antimicrobial susceptibility testing of the isolates was performed by the standardised disk diffusion method (Kirby-Bauer). Of the 59 study isolates, 32.20% were resistant to at least one antimicrobial and 16.95% showed multidrug-resistant phenotypes. Thirteen drug resistance genes [aph(3')-IIa, aac(6')-Ib, ant(3'')-Ia, aac(3)-IIa, sul1, sul2, sul3, tetA, tetC, tetM, cat1, floR and cmlA] were analysed using four primer sets by multiplex polymerase chain reaction (PCR). The detection frequency of the aph(3')-IIa gene was the highest (10.17%), followed by cmlA (8.47%). The genes aac(6')-Ib, sul2 and tetA were not detected. PCR products were confirmed by DNA sequence analysis. The results revealed that multidrug resistance was widely present in bacteria isolated from Giant pandas.

  10. Phenotypic and molecular characterization of antimicrobial resistance in Enterobacter spp. isolates from companion animals in Japan.

    Science.gov (United States)

    Harada, Kazuki; Shimizu, Takae; Mukai, Yujiro; Kuwajima, Ken; Sato, Tomomi; Kajino, Akari; Usui, Masaru; Tamura, Yutaka; Kimura, Yui; Miyamoto, Tadashi; Tsuyuki, Yuzo; Ohki, Asami; Kataoka, Yasushi

    2017-01-01

    The emergence of antimicrobial resistance among Enterobacter spp., including resistance to extended-spectrum cephalosporins (ESC), is of great concern in both human and veterinary medicine. In this study, we investigated the prevalence of antimicrobial resistance among 60 isolates of Enterobacter spp., including E. cloacae (n = 44), E. aerogenes (n = 10), and E. asburiae (n = 6), from clinical specimens of dogs and cats from 15 prefectures in Japan. Furthermore, we characterized the resistance mechanisms harbored by these isolates, including extended-spectrum β-lactamases (ESBLs) and plasmid-mediated quinolone resistance (PMQR); and assessed the genetic relatedness of ESC-resistant Enterobacter spp. strains by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Antimicrobial susceptibility testing demonstrated the resistance rates to ampicillin (93.3%), amoxicillin-clavulanic acid (93.3%), cefmetazole (93.3%), chloramphenicol (46.7%), ciprofloxacin (43.3%), tetracycline (40.0%), ceftazidime (33.3%), cefotaxime (33.3%), trimethoprim/sulfamethoxazole (28.3%), gentamicin (23.3%), and meropenem (0%). Phenotypic testing detected ESBLs in 16 of 18 ESC-resistant E. cloacae isolates but not in the other species. The most frequent ESBL was CTX-M-15 (n = 8), followed by SHV-12 (n = 7), and CTX-M-3 (n = 1). As for AmpC β-lactamases, CMY-2 (n = 2) and DHA-1 (n = 2) were identified in ESC-resistant E. cloacae strains with or without ESBLs. All of the ESC-resistant E. cloacae strains also harbored one or two PMQRs, including qnrB (n = 15), aac(6')-Ib-cr (n = 8), and qnrS (n = 2). Based on MLST and PFGE analysis, E. cloacae clones of ST591-SHV-12, ST171-CTX-M-15, and ST121-CTX-M-15 were detected in one or several hospitals. These results suggested intra- and inter-hospital dissemination of E. cloacae clones co-harboring ESBLs and PMQRs among companion animals. This is the first report on the large-scale monitoring of antimicrobial-resistant isolates

  11. Genotypic and phenotypic characterization of antimicrobial-resistant Escherichia coli from farm-raised diarrheic sika deer in Northeastern China.

    Directory of Open Access Journals (Sweden)

    Rui Li

    Full Text Available In China, overuse and/or abuse of antimicrobials are common in stockbreeding, which possess high risks of antimicrobial-resistant contaminations. The serogroups, major virulence genes, and antimicrobial resistant patterns of the antimicrobial-resistant Escherichia coli (E. coli were investigated in the feces of diarrheic farm-raised sika deer from 50 farms in three Northeastern provinces of China. A total of 220 E. coli isolates were obtained and characterized. Twenty-eight O serogroups were identified from the obtained E. coli isolates with O2, O26, O128, O142 and O154 being dominant. Nearly all the isolates were resistant to at least four of the tested antimicrobials. More than 90% of the E. coli isolates carried at least one of the tested virulence genes. About 85% of the E. coli isolates carried one or more antimicrobial-resistant genes responsible for resistant phenotypes of sulfonamides, streptomycin/spectionomycin or tetracycline. The antimicrobial resistant level and pathogenic group occurrences of the obtained E. coli isolates were higher than that of livestock and wild animals reported in some developed countries. Thus, the fecal-carrying antimicrobial-resistant E. coli from the farm-raised sika deer is potentially a significant contamination source for freshwater systems and food chain, and may pose great health risks for human and animals in Northeastern China.

  12. Use of phenotype microarrays to study the effect of acquisition of resistance to antimicrobials in bacterial physiology.

    Science.gov (United States)

    Reales-Calderon, Jose A; Blanco, Paula; Alcalde-Rico, Manuel; Corona, Fernando; Lira, Felipe; Hernando-Amado, Sara; Bernardini, Alejandra; Sánchez, María B; Martínez, José L

    It is widely accepted that the acquisition of resistance to antimicrobials confers a fitness cost. Different works have shown that the effect of acquiring resistance in bacterial physiology may be more specific than previously thought. Study of these specific changes may help to predict the outcome of resistant organisms in different ecosystems. In addition to changing bacterial physiology, acquisition of resistance either increases or reduces susceptibility to other antimicrobials. In the current article, we review recent information on the effect of acquiring resistance upon bacterial physiology, with a specific focus on studies using phenotype microarray technology. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  13. Animation of Antimicrobial Resistance

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  14. Animation of Antimicrobial Resistance

    Science.gov (United States)

    ... Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it More sharing options ... of Animation of Antimicrobial Resistance More in Antimicrobial ... Antimicrobial Resistance Monitoring System About NARMS 2015 NARMS Integrated ...

  15. Animation of Antimicrobial Resistance

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  16. Phenotypic and genotypic profiling of antimicrobial resistance in enteric Escherichia coli communities isolated from finisher pigs in Australia.

    Science.gov (United States)

    Smith, M G; Jordan, D; Gibson, J S; Cobbold, R N; Chapman, T A; Abraham, S; Trott, D J

    2016-10-01

    To assess herd-to-herd variation in antimicrobial resistance phenotypes and associated antimicrobial resistance genes (ARGs) in faecal commensal Escherichia coli communities isolated from Australian slaughter-age pigs. Hydrophobic grid-membrane filtration (HGMF) was used to screen populations of E. coli isolated from faecal samples obtained from pigs prior to or at slaughter. Multiplex PCRs were applied to the pooled DNA extracted from the samples to identify specific ARGs. Pooled faecal samples from 30 finishers, from 72 different Australian pig farms, produced 5003 isolates for screening. HGMF techniques and image analysis were used to confirm E. coli resistance phenotypes to four antimicrobial agents (ampicillin, gentamicin, florfenicol and ceftiofur) using selective agars. Multiplex PCRs were performed on DNA from pooled samples for 35 ARGs associated with seven chemical classes. The prevalence of E. coli isolates showing no resistance to any of the drugs was 50.2% (95% confidence interval (CI) 41.8-58.6%). Ceftiofur resistance was very low (1.8%; CI 0.8-3.9%) and no ARGs associated with 3rd-generation cephalosporin resistance were detected. By contrast, ampicillin (29.4%, CI 22.8-37.0%), florfenicol (24.3%, CI 17.8-32.3%) and gentamicin (CI 17.5%, 10.7-27.2%) resistance prevalence varied greatly between farms and associated ARGs were common. The most common combined resistance phenotype was ampicillin-florfenicol. The use of registered antimicrobials in Australian pigs leads to the enteric commensal populations acquiring associated ARGs. However, despite a high intensity of sampling, ARGs imparting resistance to the critically important 3rd-generation cephalosporins were not detected. © 2016 Australian Veterinary Association.

  17. 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......-the-counter sale of antibiotics, the use of antimicrobial stewardship programmes, the active participation of clinicians in audits, the utilization of valid rapid point-of-care tests, the promotion of delayed antibiotic prescribing strategies, the enhancement of communication skills with patients with the aid...... 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...

  18. Animation of Antimicrobial Resistance

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  19. Animation of Antimicrobial Resistance

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    Full Text Available ... Antimicrobial Resistance More in Antimicrobial Resistance National Antimicrobial Resistance Monitoring System About NARMS 2015 NARMS Integrated Report Data Meetings and Publications Resources Judicious Use of Antimicrobials Page Last Updated: ...

  20. Phenotypical and Genotypical Antimicrobial Resistance of Coagulase-negative staphylococci Isolated from Cow Mastitis.

    Science.gov (United States)

    Klimiene, I; Virgailis, M; Pavilonis, A; Siugzdiniene, R; Mockeliunas, R; Ruzauskas, M

    2016-09-01

    The objectives of this study were to determine the prevalence and antimicrobial resistance of coagulase-negative staphylococci (CNS) isolated from dairy cows with subclinical mastitis. Antimicrobial resistance in staphylococci were evaluated by breakpoint values specific to the species (EU-CAST). The presence of resistance-encoding genes was detected by multiplex PCR. A total of 191 CNS isolates were obtained. The CNS isolates were typically resistant to penicillin (67.4%), tetracyc-line (18.9%), and erythromycin (13.7%). CNS isolates (78.0%) were resistant to at least one antimicrobial compound, and 22.0% were multiresistant. The multiresistant isolates were predominantly Staphylococcus chromogenes (28.6%), Staphylococcus warneri (19%) and Staphylococcus haemolyticus (14.3%). According to MIC pattern data, multiresistant isolates showed the highest resistance (pchromogenes (9.5%), S. haemolyticus (4.8%), and S. capitis ss capitis (2.4%) strains were resistant to methicillin; their resistance to oxacillin and penicillin was more than 8 mg/l. A high rate of resistance to penicillin was linked to a blaZ gene found in 66.6% of the isolated multiresistant CNS strains. Resistance to tetracycline via the tetK (38.1%) gene and penicillin via the mecA (23.8%) gene were detected less frequently. Gene msrAB was responsible for macrolides and lincosamides resistance and detected in 28.6% of the CNS isolates. Antimicrobial resistance genes were identified more frequently in S. epidermidis, S. chromogenes, and S. warneri.

  1. Phenotypic antimicrobial resistance profile of isolates causing clinical mastitis in dairy animals

    Directory of Open Access Journals (Sweden)

    Carlotta Ceniti

    2017-05-01

    Full Text Available Mastitis is the most frequent and costly disease of lactating animals and is associated with a significant reduction in milk yield, increased cost and culling. Early and specific antibiotic based treatment reduces the severity of the disease. Over the years the extensive use of antimicrobials has led to increase antimicrobial resistance. The present study was designed to investigate the prevalence of microorganisms responsible for mastitis and their antimicrobial resistance pattern. A total of 282 milk samples were collected from different animal species (sheep, cows and goats with clinical mastitis. Antimicrobial resistance was evaluated for Streptococcus spp. and Staphylococcus spp. In cow samples Streptococcus spp. represented the most frequently isolated genus (33.84%, while Staphylococcus spp. was the most prevalent genus in sheep and goat samples (44.4 and 73.86%, respectively. Gentamicin and chloramphenicol were found to be the most effective drugs against the tested isolates, while the highest resistance rates were observed for amoxicillin, ampicillin, tetracycline, trimethoprim-sulfamethoxazole.

  2. Resistance phenotypes and genotypes among multiple-antimicrobial-resistant Salmonella enterica subspecies enterica serovar Choleraesuis strains isolated between 2008 and 2012 from slaughter pigs in Okinawa Prefecture, Japan.

    Science.gov (United States)

    Matayoshi, Masanao; Kitano, Takashi; Sasaki, Tetsu; Nakamura, Masaji

    2015-06-01

    A total of 349 Salmonella enterica subspecies enterica serovar Choleraesuis (S. Choleraesuis) strains, which were isolated between 2008 and 2012 from 349 pigs at two slaughterhouses in Okinawa Prefecture, Japan, were investigated for antimicrobial susceptibility and the presence of antimicrobial resistance genes. All isolates were resistant to at least four antimicrobial agents. The antimicrobial agents for which isolates showed a high incidence of resistance were as follows: ampicillin (100%) and streptomycin (100%), followed by gentamicin (99.7%), oxytetracycline (99.7%), sulfamethoxazole/trimethoprim (99.4%), nalidixic acid (40.1%) and oxolinic acid (40.1%). All isolates were sensitive to cefuroxime, ceftiofur, colistin, fosfomycin, enrofloxacin, orbifloxacin and danofloxacin. The predominant resistance phenotypes and genotypes were: resistance to ampicillin, streptomycin, gentamicin, oxytetracycline and sulfamethoxazole/trimethoprim (58.5%, 204/349) and blaTEM-strA-strB-aadA1-aadA2-aacC2-tet (B)-sul1-sul2-dhfrXII-dhfrXIII (36.1%, 126/349). The quinolone resistance-determining regions (QRDRs) of gyrA, gyrB, parC and parE of the quinolone-resistant isolates (n=12) showed amino acid substitutions of Ser-83→Phe or Asp-87→Tyr in GyrA and Ser-107→Ala in ParC. To our knowledge, this is the first report on the molecular characterization of antimicrobial resistance among S. Choleraesuis strains in Japan.

  3. Animation of Antimicrobial Resistance

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    Full Text Available ... Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it More sharing options ... produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. Over time, ...

  4. Animation of Antimicrobial Resistance

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    Full Text Available ... Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it More sharing options ... CVM) produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. Over time, ...

  5. Animation of Antimicrobial Resistance

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  6. Animation of Antimicrobial Resistance

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  7. Phenotypic and Genotypic Antimicrobial Resistance of Lactococcus Sp. Strains Isolated from Rainbow Trout (Oncorhynchus Mykiss

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    Ture Mustafa

    2015-04-01

    Full Text Available A current profile of antimicrobial resistance and plasmid of 29 Lactococcus garvieae and one Lactococcus lactis strains isolated from rainbow trouts (Oncorhynchus mykiss from farms throughout Turkey were investigated. All isolates were sensitive to penicillin G (90%, ampicillin (86.7%, florfenicol (83.3%, amoxicillin (80.1%, and tetracycline (73.4%, and resistant to trimethoprim+sulfamethoxazole (86.6% and gentamycin (46.6% by disc diffusion method. Twenty-eight (93% isolates had two to seven antibiotic resistance genes (ARGs determined by PCR. The most prevalent ARGs were tetracycline (tetB, erythromycin (ereB, and β-lactam (blaTEM. Bacterial strains were also screened for plasmid DNA by agarose gel electrophoresis and two strains harboured plasmids, with sizes ranging from 3 to 9 kb.

  8. Animation of Antimicrobial Resistance

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    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 ...

  9. 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.

  10. Animation of Antimicrobial Resistance

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    Full Text Available ... version) Arabic Translation of Animation of Antimicrobial Resistance Chinese Translation of Animation of Antimicrobial Resistance French Translation ... FEAR Act Site Map Nondiscrimination Website Policies U.S. Food and Drug Administration 10903 New Hampshire Avenue Silver ...

  11. Animation of Antimicrobial Resistance

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    Full Text Available ... Medicine (CVM) produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. ... concept more understandable to non-scientists by showing how bacterial antimicrobial resistance can develop and spread. All ...

  12. Animation of Antimicrobial Resistance

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    Full Text Available ... Home Food Drugs Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Animal & Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share ...

  13. Molecular Detection of Antimicrobial Resistance

    Science.gov (United States)

    Fluit, Ad C.; Visser, Maarten R.; Schmitz, Franz-Josef

    2001-01-01

    The determination of antimicrobial susceptibility of a clinical isolate, especially with increasing resistance, is often crucial for the optimal antimicrobial therapy of infected patients. Nucleic acid-based assays for the detection of resistance may offer advantages over phenotypic assays. Examples are the detection of the methicillin resistance-encoding mecA gene in staphylococci, rifampin resistance in Mycobacterium tuberculosis, and the spread of resistance determinants across the globe. However, molecular assays for the detection of resistance have a number of limitations. New resistance mechanisms may be missed, and in some cases the number of different genes makes generating an assay too costly to compete with phenotypic assays. In addition, proper quality control for molecular assays poses a problem for many laboratories, and this results in questionable results at best. The development of new molecular techniques, e.g., PCR using molecular beacons and DNA chips, expands the possibilities for monitoring resistance. Although molecular techniques for the detection of antimicrobial resistance clearly are winning a place in routine diagnostics, phenotypic assays are still the method of choice for most resistance determinations. In this review, we describe the applications of molecular techniques for the detection of antimicrobial resistance and the current state of the art. PMID:11585788

  14. Antimicrobial Resistance

    Science.gov (United States)

    ... life-threatening infections – to a last resort treatment (carbapenem antibiotics) has spread to all regions of the ... unit patients. In some countries, because of resistance, carbapenem antibiotics do not work in more than half ...

  15. The Transient Multidrug Resistance Phenotype ofSalmonella entericaSwarming Cells Is Abolished by Sub-inhibitory Concentrations of Antimicrobial Compounds.

    Science.gov (United States)

    Irazoki, Oihane; Campoy, Susana; Barbé, Jordi

    2017-01-01

    Swarming motility is the rapid and coordinated multicellular migration of bacteria across a moist surface. During swarming, bacterial cells exhibit increased resistance to multiple antibiotics, a phenomenon described as adaptive or transient resistance. In this study, we demonstrate that sub-inhibitory concentrations of cefotaxime, ciprofloxacin, trimethoprim, or chloramphenicol, but not that of amikacin, colistin, kanamycin or tetracycline, impair Salmonella enterica swarming. Chloramphenicol-treated S. enterica cells exhibited a clear decrease in their flagellar content, while treatment with other antibiotics that reduced swarming (cefotaxime, ciprofloxacin, and trimethoprim) inhibited polar chemoreceptor array assembly. Moreover, the increased resistance phenotype acquired by swarming cells was abolished by the presence of these antimicrobials. The same occurred in cells treated with these antimicrobial agents in combination with others that had no effect on swarming motility. Our results reveal the potential of inhibiting swarming ability to enhance the therapeutic effectiveness of antimicrobial agents.

  16. Phenotypic and genotypic characterization of antimicrobial resistance in enterohemorrhagic Escherichia coli and atypical enteropathogenic E. coli strains from ruminants.

    Science.gov (United States)

    Medina, Alberto; Horcajo, Pilar; Jurado, Sonia; De la Fuente, Ricardo; Ruiz-Santa-Quiteria, José A; Domínguez-Bernal, Gustavo; Orden, José A

    2011-01-01

    Two hundred and twenty-six attaching and effacing Escherichia coli (AEEC) strains (20 enterohemorrhagic E. coli and 206 atypical enteropathogenic E. coli) isolated from calves, lambs, and goat kids with diarrhea and from healthy cattle, sheep, and goats were tested for their resistance to 10 antimicrobial agents by the disc diffusion method. Resistant and intermediate strains were analyzed by polymerase chain reaction for the presence of the major resistance genes. The overall percentage of resistant strains to tetracycline, streptomycin, erythromycin, and sulfamethoxazole was very high (>65%). Moreover, a high level of resistance (approximately 30%) to ampicillin, chloramphenicol, trimethoprim, and trimethoprim-sulfamethoxazole was also detected. The AEEC strains were very susceptible (>90%) to gentamicin and colistin. Because AEEC from ruminants can cause diseases in human beings, the high frequency of antimicrobial resistance detected in the current study is a source of concern. For each antimicrobial agent, the predominant resistance genes in the resistant strains were ampicillin, bla(TEM) (97.1%); tetracycline, tetA (76.7%); gentamicin, aac(3)II (80%); streptomycin, strA/strB (76.7%) and aadA (71.7%); chloramphenicol, catI (85.1%); trimethoprim, dhfrI (76.3%); and sulfamethoxazole, sul1 (60%) and sul2 (63.3%). In the majority of cases, resistance to a given antimicrobial, except for streptomycin, was caused by a single gene. A negative association between tetA and tetB, between aac(3)II and aac(3)IV, and between dhfrI and dhfrV was observed. The present study gives baseline data on frequency and molecular basis of antimicrobial resistance in AEEC strains from ruminants.

  17. Animation of Antimicrobial Resistance

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    Full Text Available ... topics menu Skip to common links HHS U.S. Department of Health and Human Services U.S. Food and ... More in Antimicrobial Resistance National Antimicrobial Resistance Monitoring System ... If you need help accessing information in different file formats, see Instructions for Downloading ...

  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 to select the appropriate antimicrobial for treatment. Accordingly, efforts are underway in both veterinary and human medicine to preserve the effectiveness of these drugs. ...

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    Full Text Available ... to make the concept of antimicrobial resistance more real and understandable to veterinarians, livestock producers, lawmakers, consumer ... FEAR Act Site Map Nondiscrimination Website Policies U.S. Food and Drug Administration 10903 New Hampshire Avenue Silver ...

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  7. Detection of Enterohemorrhagic Escherichia coli Related Genes in E. coli Strains Belonging to B2 Phylogroup Isolated from Urinary Tract Infections in Combination with Antimicrobial Resistance Phenotypes

    Directory of Open Access Journals (Sweden)

    Hamid Staji

    2017-07-01

    Full Text Available Background:  This study was conducted to detect the prevalence of EHEC virulence genes and antimicrobial resistance profile of Escherichia coli strains belonging to B2 phylogroup implicated in Urinary tract infections in Semnan, Iran.Methods:   From 240 urine samples 160 E. coli strains were isolated, biochemically. Then, E. coli isolates were examined by Multiplex-PCR for phylogenetic typing and detection of virulence genes (hly, stx1, stx2, eae associated with Enterohemorrhagic E. coli. Finally, Antimicrobial resistance of E. coli isolates were characterized using Disk Diffusion method.  Results:  From 160 E. coli isolates, 75 strains (47% were assigned to B2 phylogenetic group and prevalence of virulence genes were as follow: hly (21.3%, stx1 (16%, stx2 (10.6% and eae (6.7%, subsequently.  Phenotypic antimicrobial resistance of B2 isolates showed that all isolates were sensitive to Meropenem and Furazolidone and then highest frequency of resistance was observed to Streptomycin, Oxytetracycline, Neomycin, Nalidixic acid and Ampicillin (98.7% to 49.3%. Also low resistance prevalence was observed in case of Ceftizoxime, Lincospectin, Imipenem, Chloramphenicol and flurefenicole (16% to 1.3%.Conclusion:   The data suggest a high prevalence of antibiotic resistance in UPEC strains belonging to B2 phylogroup even for the antimicrobials using in pet and farm animals and their potential to cause EHEC specific clinical symptoms which may represent a serious health risk since these strains can be transmitted to GI tract and act as a reservoir for other uropathogenic E. coli and commensal strains.

  8. The phenotypic and genotypic characteristics of antibiotic resistance in Escherichia coli populations isolated from farm animals with different exposure to antimicrobial agents.

    Science.gov (United States)

    Mazurek, Justyna; Pusz, Paweł; Bok, Ewa; Stosik, Michał; Baldy-Chudzik, Katarzyna

    2013-01-01

    The aim of the study was to determine the influence of the presence or the absence of antibiotic input on the emergence and maintenance of resistance in commensal bacteria from food producing animals. The research material constituted E. coli isolates from two animal species: swine at different age from one conventional pig farm with antibiotic input in young pigs and from beef and dairy cattle originated from organic breeding farm. The sensitivity to 16 antimicrobial agents was tested, and the presence of 15 resistance genes was examined. In E. coli from swine, the most prevalent resistance was resistance to streptomycin (88.3%), co-trimoxazole (78.8%), tetracycline (57.3%) ampicillin (49.3%) and doxycycline (44.9%) with multiple resistance in the majority. The most commonly observed resistance genes were: bla(TEM) (45.2%), tetA (35.8%), aadA1 (35.0%), sul3 (29.5%), dfrA1 (20.4%). Differences in phenotypes and genotypes of E. coli between young swine undergoing prevention program and the older ones without the antibiotic pressure occurred. A disparate resistance was found in E. coli from cattle: cephalothin (36.9%), cefuroxime (18.9%), doxycycline (8.2%), nitrofurantoin (7.7%), and concerned mainly dairy cows. Among isolates from cattle, multidrug resistance was outnumbered by resistance to one or two antibiotics and the only found gene markers were: bla(SHV), (3.4%), tetA (1.29%), bla(TEM) (0.43%) and tetC (0.43%). The presented outcomes provide evidence that antimicrobial pressure contributes to resistance development, and enteric microflora constitutes an essential reservoir of resistance genes.

  9. Phenotypic and molecular characterization of antimicrobial resistance and virulence factors in Pseudomonas aeruginosa clinical isolates from Recife, State of Pernambuco, Brazil

    Directory of Open Access Journals (Sweden)

    Paula Regina Luna de Araújo Jácome

    2012-12-01

    Full Text Available INTRODUCTION: The emergence of carbapenem resistance mechanisms in Pseudomonas aeruginosa has been outstanding due to the wide spectrum of antimicrobial degradation of these bacteria, reducing of therapeutic options. METHODS: Sixty-one clinical strains of P. aeruginosa isolated from five public hospitals in Recife, Pernambuco, Brazil, were examined between 2006 and 2010, aiming of evaluating the profiles of virulence, resistance to antimicrobials, presence of metallo-β-lactamase (MBL genes, and clonal relationship among isolates. RESULTS: A high percentage of virulence factors (34.4% mucoid colonies; 70.5% pyocyanin; 93.4% gelatinase positives; and 72.1% hemolysin positive and a high percentage of antimicrobial resistance rates (4.9% pan-resistant and 54.1% multi-drug resistant isolates were observed. Among the 29 isolates resistant to imipenem and/or ceftazidime, 44.8% (13/29 were MBL producers by phenotypic evaluation, and of these, 46.2% (6/13 were positive for the blaSPM-1 gene. The blaIMP and blaVIM genes were not detected. The molecular typing revealed 21 molecular profiles of which seven were detected in distinct hospitals and periods. Among the six positive blaSPM-1 isolates, three presented the same clonal profile and were from the same hospital, whereas the other three presented different clonal profiles. CONCLUSIONS: These results revealed that P. aeruginosa is able to accumulate different resistance and virulence factors, making the treatment of infections difficult. The identification of blaSPM-1 genes and the dissemination of clones in different hospitals, indicate the need for stricter application of infection control measures in hospitals in Recife, Brazil, aiming at reducing costs and damages caused by P. aeruginosa infections.

  10. Phenotypic and Genotypic Antimicrobial Resistance Profiles of Campylobacter jejuni Isolated from Cattle, Sheep, and Free-Range Poultry Faeces

    Directory of Open Access Journals (Sweden)

    Beatriz Oporto

    2009-01-01

    Full Text Available Minimum inhibitory concentrations (MIC of 13 antimicrobial agents were determined by broth microdilution for 72 Campylobacter jejuni strains from livestock. Twenty-three (31.9% isolates were fully susceptible; all isolates were susceptible to erythromycin, chloramphenicol, streptomycin, gentamicin, sulfamethoxazole, and meropenem, and all but one to kanamycin. Resistance to quinolones was highest (52.8%, reaching similar values among poultry, dairy cattle, and sheep, but lower in beef cattle. Resistance to tetracyclines (48.6% was mainly associated to dairy cattle and β-lactams (26.4% to poultry. Multidrug resistance was mainly detected in dairy cattle (28.6% and poultry (21.0%, whereas beef cattle had the highest percentage of fully susceptible isolates. Two real-time PCR assays to detect point mutations associated to quinolone (C257T in the gyrA gene and macrolide (A2075G in the 23S rRNA genes resistance were developed and validated on these strains. The analysis of a further set of 88 isolates by real-time PCR confirmed the absence of macrolide resistance and demonstrated the reproducibility and processability of the assay.

  11. Phenotypic and genotypic properties of Neisseria gonorrhoeae isolates in Norway in 2009: antimicrobial resistance warrants an immediate change in national management guidelines.

    Science.gov (United States)

    Hjelmevoll, S O; Golparian, D; Dedi, L; Skutlaberg, D H; Haarr, E; Christensen, A; Jørgensen, S; Nilsen, Ø J; Unemo, M; Skogen, V

    2012-06-01

    Despite rapidly diminishing treatment options for Neisseria gonorrhoeae and high levels of ciprofloxacin resistance worldwide, Norwegian guidelines still recommend ciprofloxacin as empirical treatment for gonorrhea. The present study aimed to characterize phenotypical and genotypical properties of N. gonorrhoeae isolates in Norway in 2009. All viable N. gonorrhoeae isolates (n = 114) from six university hospitals in Norway (2009) were collected, representing 42% of all notified gonorrhea cases. Epidemiological data were collected from the Norwegian Surveillance System for Communicable Diseases and linked to phenotypical and genotypical characteristics for each N. gonorrhoeae isolate. Resistance levels to the antimicrobials examined were: ciprofloxacin 78%, azithromycin 11%, cefixime 3.5%, ceftriaxone 1.8%, and spectinomycin 0%. The minimum inhibitory concentrations of gentamicin varied from 1.5 to 8 mg/L. Forty-one (36%) of the isolates were β-lactamase-producing, 17 displayed penA mosaic alleles, and 72 different N. gonorrhoeae multiantigen sequence types (ST; 37 novel) were identified. The most common ST was ST1407 (n = 11), containing penA mosaic allele. Four of these isolates displayed intermediate susceptibility/resistance to cefixime. The N. gonorrhoeae strains circulating in Norway were highly diverse. The level of ciprofloxacin resistance was high and the Norwegian management guidelines should promptly exclude ciprofloxacin as an empirical treatment option for gonorrhea.

  12. 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...

  13. Animation of Antimicrobial Resistance

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  14. Animation of Antimicrobial Resistance

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    Full Text Available ... 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 ...

  15. Animation of Antimicrobial Resistance

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  16. Animation of Antimicrobial Resistance

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    Full Text Available ... emerges and proliferates among bacteria. Over time, the use of antimicrobial drugs will result in the development of resistant strains ... human medicine to preserve the effectiveness of these drugs. One of the major obstacles to understanding the ... Page Last Updated: 02/23/2018 ...

  17. 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...... and pigs were susceptible to avilamycin, whereas 35% of isolates from broilers were resistant. All E. faecium isolates from humans were susceptible to vancomycin, whereas 10% and 17% of isolates from broilers and pigs, respectively, were resistant. A vancomycin resistant E. faecium isolate was found in one....... faecium isolates of human and animal origin, examined. tet(K) was not observed, whereas tet(L) was detected in 17% of tetracycline resistant E. faecalis isolates and in 16% of the E. faecium isolates. tet(O) was not detected in any of the isolates from pigs, but was observed in 38% of E. faecalis isolates...

  18. Profile of antimicrobial susceptibility isolated microorganisms from hospitalized patients in PICU ward and detection of Methicillin-resistant Staphylococcus aureus and ESBL-producing bacteria by phenotypic methods

    Directory of Open Access Journals (Sweden)

    Shahla Abbas Poor

    2014-10-01

    Full Text Available Background: Hospital-acquired infections are a major challenge to patient. A range of gram-negative organisms are responsible for hospital-acquired infections, the Enterobacteriaceae family being the most commonly identified group overall. Infections by ESBL producers are associated with severe adverse clinical outcomes that have led to increased mortality, prolonged hospitalization, and rising medical costs. The aim of this study was to survey profile of antimicrobial susceptibility isolated microorganisms from hospitalized patients in PICU ward and detection of methicillin-resistant Staphylococcus aureus and ESBL-producing bacteria by phenotypic methods. Material and Methods: In this study participants were patients hospitalized in PICU part of Bahrami Hospital, Tehran, with attention to involved organ. For isolation of bacteria from patient’s samples, culture performed on different selective and differential media. After confirmation of bacteria by biochemical tests, susceptibility testing was performed by disc diffusion method. Phenotypic detection of MRSA strains was performed using cefoxcitin disc. ESBL producing strains were detected by ceftazidime (CAZ and ceftazidime/clavulanic acid (CAZ/CLA discs. Results: Among all isolated organisms from clinical samples, the most common isolated organisms were Escherichia coli (24 cases, Pseudomonas areoginosa (9 cases and Staphylococcus aureus (8 cases, respectively. Among eight MRSA isolated strains from different clinical samples, six strains (75% were MRSA. Among 52 isolated gram negative organisms, 5 strains (9/6% were ESBL. Conclusion: Standard interventions to prevent the transmission of antimicrobial resistance in health care facilities include hand hygiene, using barrier precautions in the care of colonized and infected patients, using dedicated instruments and equipment for these patients. The colonized or infected patients should be isolated in single rooms, multibed rooms or areas

  19. Strategies to combat antimicrobial resistance.

    Science.gov (United States)

    Uchil, Rajesh R; Kohli, Gurdeep Singh; Katekhaye, Vijay M; Swami, Onkar C

    2014-07-01

    The global burden of antimicrobial resistance is rising and is associated with increased morbidity and mortality in clinical and community setting. Spread of antibiotic resistance to different environmental niches and development of superbugs have further complicated the effective control strategies. International, national and local approaches have been advised for control and prevention of antimicrobial resistance. Rational use of antimicrobials, regulation on over-the-counter availability of antibiotics, improving hand hygiene and improving infection prevention and control are the major recommended approaches. Thorough understanding of resistance mechanism and innovation in new drugs and vaccines is the need. A multidisciplinary, collaborative, regulatory approach is demanded for combating antimicrobial resistance.

  20. 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.

  1. Antimicrobial resistant coagulase positive Staphylococcus aureus ...

    African Journals Online (AJOL)

    ADEYEYE

    Isolates of coagulase positive S. aureus resistance to 10 antimicrobials was determined by disc diffusion method. Staphylococcus .... Table 1: Antimicrobial resistance of coagulase positive Staphylococcus. aureus isolates from chickens in Maiduguri,. Nigeria. Antimicrobials .... on Danish poultry and pig farms. Preventive.

  2. 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....

  3. Antimicrobial resistance in the environment

    National Research Council Canada - National Science Library

    Keen, Patricia L; Montforts, M. H. M. M

    2012-01-01

    ... or antibiotic resistance genes as environmental contaminants. It also considers alternate uses and functions for antimicrobial compounds other than those intended for medicinal purposes in humans, animals, and fish...

  4. Phenotypic and Molecular Characterization of Antimicrobial Resistance in Klebsiella spp. Isolates from Companion Animals in Japan: Clonal Dissemination of Multidrug-Resistant Extended-Spectrum β-Lactamase-Producing Klebsiella pneumoniae

    Science.gov (United States)

    Harada, Kazuki; Shimizu, Takae; Mukai, Yujiro; Kuwajima, Ken; Sato, Tomomi; Usui, Masaru; Tamura, Yutaka; Kimura, Yui; Miyamoto, Tadashi; Tsuyuki, Yuzo; Ohki, Asami; Kataoka, Yasushi

    2016-01-01

    The emergence of antimicrobial resistance in Klebsiella spp., including resistance to extended-spectrum cephalosporins (ESC) and fluoroquinolones, is of great concern in both human and veterinary medicine. In this study, we investigated the prevalence of antimicrobial resistance in a total of 103 Klebsiella spp. isolates, consisting of Klebsiella pneumoniae complex (KP, n = 89) and K. oxytoca (KO, n = 14) from clinical specimens of dogs and cats in Japan. Furthermore, we characterized the resistance mechanisms, including extended-spectrum β-lactamase (ESBL), plasmid-mediated AmpC β-lactamase (PABL), and plasmid-mediated quinolone resistance (PMQR); and assessed genetic relatedness of ESC-resistant Klebsiella spp. strains by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Antimicrobial susceptibility testing demonstrated that resistance rates to ampicillin, cephalothin, enrofloxacin, ciprofloxacin, trimethoprim/sulfamethoxazole, cefotaxime, gentamicin, tetracycline, chloramphenicol, amoxicillin-clavulanic acid, and cefmetazole were 98.1, 37.9, 37.9, 35.9, 35.0, 34.0, 31.1, 30.1, 28.2, 14.6, and 6.8%, respectively. Phenotypic testing detected ESBLs and/or AmpC β-lactamases in 31 of 89 (34.8%) KP isolates, but not in KO isolates. Resistances to 5 of the 12 antimicrobials tested, as well as the three PMQRs [qnrB, qnrS, and aac(6′)-Ib-cr], were detected significantly more frequently in ESBL-producing KP, than in non-ESBL-producing KP and KO. The most frequent ESBL was CTX-M-15 (n = 13), followed by CTX-M-14 (n = 7), CTX-M-55 (n = 6), SHV-2 (n = 5), CTX-M-2 (n = 2), and CTX-M-3 (n = 2). Based on the rpoB phylogeny, all ESBL-producing strains were identified as K. pneumoniae, except for one CTX-M-14-producing strain, which was identified as K. quasipneumoniae. All of AmpC β-lactamase positive isolates (n = 6) harbored DHA-1, one of the PABLs. Based on MLST and PFGE analysis, ST15 KP clones producing CTX-M-2, CTX-M-15, CTX-M-55, and

  5. Antimicrobial resistance mechanisms among Campylobacter.

    Science.gov (United States)

    Wieczorek, Kinga; Osek, Jacek

    2013-01-01

    Campylobacter jejuni and Campylobacter coli are recognized as the most common causative agents of bacterial gastroenteritis in the world. Humans most often become infected by ingesting contaminated food, especially undercooked chicken, but also other sources of bacteria have been described. Campylobacteriosis is normally a self-limiting disease. Antimicrobial treatment is needed only in patients with more severe disease and in those who are immunologically compromised. The most common antimicrobial agents used in the treatment of Campylobacter infections are macrolides, such as erythromycin, and fluoroquinolones, such as ciprofloxacin. Tetracyclines have been suggested as an alternative choice in the treatment of clinical campylobacteriosis but in practice are not often used. However, during the past few decades an increasing number of resistant Campylobacter isolates have developed resistance to fluoroquinolones and other antimicrobials such as macrolides, aminoglycosides, and beta-lactams. Trends in antimicrobial resistance have shown a clear correlation between use of antibiotics in the veterinary medicine and animal production and resistant isolates of Campylobacter in humans. In this review, the patterns of emerging resistance to the antimicrobial agents useful in treatment of the disease are presented and the mechanisms of resistance to these drugs in Campylobacter are discussed.

  6. Antimicrobial Resistance Mechanisms among Campylobacter

    Science.gov (United States)

    2013-01-01

    Campylobacter jejuni and Campylobacter coli are recognized as the most common causative agents of bacterial gastroenteritis in the world. Humans most often become infected by ingesting contaminated food, especially undercooked chicken, but also other sources of bacteria have been described. Campylobacteriosis is normally a self-limiting disease. Antimicrobial treatment is needed only in patients with more severe disease and in those who are immunologically compromised. The most common antimicrobial agents used in the treatment of Campylobacter infections are macrolides, such as erythromycin, and fluoroquinolones, such as ciprofloxacin. Tetracyclines have been suggested as an alternative choice in the treatment of clinical campylobacteriosis but in practice are not often used. However, during the past few decades an increasing number of resistant Campylobacter isolates have developed resistance to fluoroquinolones and other antimicrobials such as macrolides, aminoglycosides, and beta-lactams. Trends in antimicrobial resistance have shown a clear correlation between use of antibiotics in the veterinary medicine and animal production and resistant isolates of Campylobacter in humans. In this review, the patterns of emerging resistance to the antimicrobial agents useful in treatment of the disease are presented and the mechanisms of resistance to these drugs in Campylobacter are discussed. PMID:23865047

  7. Animation of Antimicrobial Resistance

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    Full Text Available ... Monitoring System About NARMS 2015 NARMS Integrated Report Data Meetings and Publications Resources Judicious Use of Antimicrobials ... Federal, State & Local Officials Consumers Health Professionals Science & Research Industry Scroll back to top Popular Content Home ...

  8. Animation of Antimicrobial Resistance

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    Full Text Available ... More sharing options Linkedin Pin it Email Print The Food and Drug Administration's (FDA's) Center for Veterinary ... both emerges and proliferates among bacteria. Over time, the use of antimicrobial drugs will result in the ...

  9. Animation of Antimicrobial Resistance

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    Full Text Available ... Integrated Report Data Meetings and Publications Resources Judicious Use of Antimicrobials Page Last Updated: 02/23/2018 Note: If you need help accessing information in different file formats, see Instructions for Downloading Viewers and Players . Language Assistance Available: Español | 繁體ä¸æ–‡ | ...

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  11. Leading Antimicrobial Drug-Resistant Diseases

    Science.gov (United States)

    ... supporting research on several organisms that have developed resistance to antimicrobial drug treatment. The institute manages a research portfolio of grants aimed at the problem of antimicrobial resistance and hospital-acquired infections. Here is a list ...

  12. Antimicrobial Drug Resistance and Gonorrhea

    Centers for Disease Control (CDC) Podcasts

    2017-12-26

    Dr. Robert Kirkcaldy, a medical officer at CDC, discusses his article on antimicrobial resistance and gonorrhea.  Created: 12/26/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 12/26/2017.

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  14. Antimicrobial (Drug) Resistance

    Science.gov (United States)

    ... causes of resistance. Learn more about research and investigations currently underway . Clinical Research Clinical research projects related ... Interest for NIAID’s Small Business Program Division of AIDS High-Priority Areas of Interest Division of Allergy, ...

  15. Machine learning: novel bioinformatics approaches for combating antimicrobial resistance.

    Science.gov (United States)

    Macesic, Nenad; Polubriaginof, Fernanda; Tatonetti, Nicholas P

    2017-12-01

    Antimicrobial resistance (AMR) is a threat to global health and new approaches to combating AMR are needed. Use of machine learning in addressing AMR is in its infancy but has made promising steps. We reviewed the current literature on the use of machine learning for studying bacterial AMR. The advent of large-scale data sets provided by next-generation sequencing and electronic health records make applying machine learning to the study and treatment of AMR possible. To date, it has been used for antimicrobial susceptibility genotype/phenotype prediction, development of AMR clinical decision rules, novel antimicrobial agent discovery and antimicrobial therapy optimization. Application of machine learning to studying AMR is feasible but remains limited. Implementation of machine learning in clinical settings faces barriers to uptake with concerns regarding model interpretability and data quality.Future applications of machine learning to AMR are likely to be laboratory-based, such as antimicrobial susceptibility phenotype prediction.

  16. Antimicrobial resistance of mastitis pathogens.

    Science.gov (United States)

    Oliver, Stephen P; Murinda, Shelton E

    2012-07-01

    Antibiotics are used extensively in the dairy industry to combat disease and to improve animal performance. Antibiotics such as penicillin, cephalosporin, streptomycin, and tetracycline are used for the treatment and prevention of diseases affecting dairy cows caused by a variety of gram-positive and gram-negative bacteria. Antibiotics are often administrated routinely to entire herds to prevent mastitis during the dry period. An increase in the incidence of disease in a herd generally results in increased use of antimicrobials, which in turn increases the potential for antibiotic residues in milk and the potential for increased bacterial resistance to antimicrobials. Continued use of antibiotics in the treatment and prevention of diseases of dairy cows will continue to be scrutinized. It is clear that strategies employing the prudent use of antimicrobials are needed. This clearly illustrates the importance of effective herd disease prevention and control programs. Based on studies published to date, scientific evidence does not support widespread, emerging resistance among mastitis pathogens to antibacterial drugs even though many of these antibiotics have been used in the dairy industry for treatment and prevention of disease for several decades. However, it is clear that use of antibiotics in dairy cows can contribute to increased antimicrobial resistance. While antimicrobial resistance does occur, we are of the opinion that the advantages of using antibiotics for the treatment of mastitis far outweigh the disadvantages. The clinical consequences of antimicrobial resistance of dairy pathogens affecting humans appear small. Antimicrobial resistance among dairy pathogens, particularly those found in milk, is likely not a human health concern as long as the milk is pasteurized. However, there are an increasing number of people who choose to consume raw milk. Transmission of an antimicrobial-resistant mastitis pathogen and/or foodborne pathogen to humans could occur

  17. Postoperative Nosocomial Infections and Antimicrobial Resistance ...

    African Journals Online (AJOL)

    Postoperative Nosocomial Infections and Antimicrobial Resistance Pattern of Bacteria Isolates among Patients Admitted at Felege Hiwot Referral Hospital, Bahirdar, ... Wound swab and venous blood samples were collected and processed for bacterial isolation and antimicrobial susceptibility testing following standard ...

  18. [Study of phenotypical and antimicrobial susceptibility markers in enteric Escherichia coli strains].

    Science.gov (United States)

    Aguila, Adalberto; Bernedo, Robert; Llop, Alina; Ramírez, Margarita; Bravo, Laura; Fernández, Anabel; Ledo, Yudith

    2007-01-01

    Forty strains of Escherichia coli isolated from children under 5 years of age with acute diarreas, coming from different provinces of the country , were analyzed. Four important phenotypical determinants were tested: sorbosa, sorbitol, enterohemolysin and 0157:H7 serology, in order to select those strains from enterohemorrhagic or Shiga toxin-producing category. Likewise, they were characterized by biotyping and antimicrobial susceptibility methods. The use of phenotypical tests showed six strains with presumptive characteristics, four of which were most likely to be Shiga toxin-producing strains. In antimicrobial susceptibility test, the strains showed high resistance mainly to ampicillin and trimethrophin-sulfamethoxasole. Another interesting finding were intermediate resistance and susceptibility values to augmentin, aztreonan and ceftriaxone. There were 12 antimicrobial resistance patterns of which 10 were multi-resistant.

  19. Antimicrobial resistance challenged with metal-based antimicrobial macromolecules.

    Science.gov (United States)

    Abd-El-Aziz, Alaa S; Agatemor, Christian; Etkin, Nola

    2017-02-01

    Antimicrobial resistance threatens the achievements of science and medicine, as it deactivates conventional antimicrobial therapeutics. Scientists respond to the threat by developing new antimicrobial platforms to prevent and treat infections from these resistant strains. Metal-based antimicrobial macromolecules are emerging as an alternative to conventional platforms because they combine multiple mechanisms of action into one platform due to the distinctive properties of metals. For example, metals interact with intracellular proteins and enzymes, and catalyse various intracellular processes. The macromolecular architecture offers a means to enhance antimicrobial activity since several antimicrobial moieties can be conjugated to the scaffold. Further, these macromolecules can be fabricated into antimicrobial materials for contact-killing medical implants, fabrics, and devices. As volatilization or leaching out of the antimicrobial moieties from the macromolecular scaffold is reduced, these medical implants, fabrics, and devices can retain their antimicrobial activity over an extended period. Recent advances demonstrate the potential of metal-based antimicrobial macromolecules as effective platforms that prevent and treat infections from resistant strains. In this review these advances are thoroughly discussed within the context of examples of metal-based antimicrobial macromolecules, their mechanisms of action and biocompatibility. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Antimicrobial usage and resistance in beef production

    OpenAIRE

    Cameron, Andrew; McAllister, Tim A.

    2016-01-01

    Antimicrobials are critical to contemporary high-intensity beef production. Many different antimicrobials are approved for beef cattle, and are used judiciously for animal welfare, and controversially, to promote growth and feed efficiency. Antimicrobial administration provides a powerful selective pressure that acts on the microbial community, selecting for resistance gene determinants and antimicrobial-resistant bacteria resident in the bovine flora. The bovine microbiota includes many harm...

  1. 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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. WGS accurately predicts antimicrobial resistance in Escherichia coli.

    Science.gov (United States)

    Tyson, Gregory H; McDermott, Patrick F; Li, Cong; Chen, Yuansha; Tadesse, Daniel A; Mukherjee, Sampa; Bodeis-Jones, Sonya; Kabera, Claudine; Gaines, Stuart A; Loneragan, Guy H; Edrington, Tom S; Torrence, Mary; Harhay, Dayna M; Zhao, Shaohua

    2015-10-01

    The objective of this study was to determine the effectiveness of WGS in identifying resistance genotypes of MDR Escherichia coli and whether these correlate with observed phenotypes. Seventy-six E. coli strains were isolated from farm cattle and measured for phenotypic resistance to 15 antimicrobials with the Sensititre(®) system. Isolates with resistance to at least four antimicrobials in three classes were selected for WGS using an Illumina MiSeq. Genotypic analysis was conducted with in-house Perl scripts using BLAST analysis to identify known genes and mutations associated with clinical resistance. Over 30 resistance genes and a number of resistance mutations were identified among the E. coli isolates. Resistance genotypes correlated with 97.8% specificity and 99.6% sensitivity to the identified phenotypes. The majority of discordant results were attributable to the aminoglycoside streptomycin, whereas there was a perfect genotype-phenotype correlation for most antibiotic classes such as tetracyclines, quinolones and phenicols. WGS also revealed information about rare resistance mechanisms, such as structural mutations in chromosomal copies of ampC conferring third-generation cephalosporin resistance. WGS can provide comprehensive resistance genotypes and is capable of accurately predicting resistance phenotypes, making it a valuable tool for surveillance. Moreover, the data presented here showing the ability to accurately predict resistance suggest that WGS may be used as a screening tool in selecting anti-infective therapy, especially as costs drop and methods improve. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  3. Correlations between Income inequality and antimicrobial resistance.

    Science.gov (United States)

    Kirby, Andrew; Herbert, Annie

    2013-01-01

    The aim of this study is to investigate if correlations exist between income inequality and antimicrobial resistance. This study's hypothesis is that income inequality at the national level is positively correlated with antimicrobial resistance within developed countries. Income inequality data were obtained from the Standardized World Income Inequality Database. Antimicrobial resistance data were obtained from the European antimicrobial Resistance Surveillance Network and outpatient antimicrobial consumption data, measured by Defined daily Doses per 1000 inhabitants per day, from the European Surveillance of antimicrobial Consumption group. Spearman's correlation coefficient (r) defined strengths of correlations of: > 0.8 as strong, > 0.5 as moderate and > 0.2 as weak. Confidence intervals and p values were defined for all r values. Correlations were calculated for the time period 2003-10, for 15 European countries. Income inequality and antimicrobial resistance correlations which were moderate or strong, with 95% confidence intervals > 0, included the following. Enterococcus faecalis resistance to aminopenicillins, vancomycin and high level gentamicin was moderately associated with income inequality (r= ≥0.54 for all three antimicrobials). Escherichia coli resistance to aminoglycosides, aminopenicillins, third generation cephalosporins and fluoroquinolones was moderately-strongly associated with income inequality (r= ≥0.7 for all four antimicrobials). Klebsiella pneumoniae resistance to third generation cephalosporins, aminoglycosides and fluoroquinolones was moderately associated with income inequality (r= ≥0.5 for all three antimicrobials). Staphylococcus aureus methicillin resistance and income inequality were strongly associated (r=0.87). As income inequality increases in European countries so do the rates of antimicrobial resistance for bacteria including E. faecalis, E. coli, K. pneumoniae and S. aureus. Further studies are needed to confirm these

  4. Antimicrobial resistance among commensal Escherichia coli from ...

    African Journals Online (AJOL)

    Commensal bacteria contribute to the distribution and persistence of antimicrobial resistance in the environment. This study monitored antimicrobial resistance in commensal Escherichia coli from the faeces of on-farm and slaughter cattle and beef. A total of 342 (89.5%) E. coli isolates were obtained from 382 samples.

  5. Antimicrobial resistance issues in beef production

    Science.gov (United States)

    Antimicrobial resistance threats to human health as identified have been recognized as a critical global public health concern. Linkage of some threats to beef production is discussed. The relevance to beef production of recent government actions will be examined. Prominent antimicrobial resistance ...

  6. Antimicrobial resistance among commensal Escherichia coli from ...

    African Journals Online (AJOL)

    user1

    2012-07-19

    Jul 19, 2012 ... Commensal bacteria contribute to the distribution and persistence of antimicrobial resistance in the environment. This study monitored antimicrobial resistance in commensal Escherichia coli from the faeces of on-farm and slaughter cattle and beef. A total of 342 (89.5%) E. coli isolates were obtained.

  7. Antimicrobial resistance patterns and plasmid profiles of ...

    African Journals Online (AJOL)

    Objectives: To determine the frequency of resistance of Staphylococcus aureus to various antimicrobial agents, and the relationship between antimicrobial resistance of the isolates and carriage of plasmids. Design: A random sampling of milk and meat samples was carried out. Setting: Milk was collected from various dairy ...

  8. 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...... the availability of tetracycline as non-registered speciality products. The focus on consumption of antimicrobials and on resistance prompted a number of initiatives by Danish authorities to limit the increase in antimicrobial resistance. One such initiative was the implementation of an integrated programme...... 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...

  9. 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...... to fluoroquinolones, which are used for empirical treatment of diarrhea in humans. Resistance to vancomycin and Synercid((R)) in enterococci is associated with use of similar drugs as growth promoters in food animals. Danish food animal producers have terminated the use of antimicrobial growth promoters. This has...... reduced the total use of antimicrobials by more than 50% and markedly reduced levels of resistance. There is an urgent need to implement globally, WHO principles for prudent use of antimicrobials in food animals. Use of antimicrobials as growth promoters could and should be terminated completely....

  10. Identification mission on Antimicrobial resistance in Indonesia

    NARCIS (Netherlands)

    Claassen, I.J.T.M.; Wagenaar, J.A.; Schreijer, Anja

    2015-01-01

    This report contains the findings and recommendations on antimicrobial use (AMU) and antimicrobial resistance (AMR) practice and policies in Indonesia.
    The observations were made by a team of Dutch and Indonesian experts during an identification mission in August 2015. The mission did address

  11. Mechanisms of bacterial resistance to antimicrobial agents.

    NARCIS (Netherlands)

    van Duijkeren, Engeline; Schink, Anne-Kathrin; Roberts, Marilyn C; Wang, Yang; Schwarz, Stefan

    During the past decades resistance to virtually all antimicrobial agents has been observed in bacteria of animal origin. This chapter describes in detail the mechanisms so far encountered for the various classes of antimicrobial agents. The main mechanisms include enzymatic inactivation by either

  12. Antimicrobial Activity of Actinomycetes Against Multidrug Resistant ...

    African Journals Online (AJOL)

    Antimicrobial Activity of Actinomycetes Against Multidrug Resistant Staphylococcus aureus, E. coli and Various Other Pathogens. ... Results: Among these isolates, 51 (38 %) showed antimicrobial activity against one or more test organisms and six exhibited promising broad-spectrum activity against all the tested organisms.

  13. Plasmids carrying antimicrobial resistance genes in Enterobacteriaceae

    NARCIS (Netherlands)

    Rozwandowicz, M.; Brouwer, M.S.M.; Fischer, J.; Wagenaar, J.A.; Gonzalez-Zorn, B.; Guerra, B.; Mevius, D.J.; Hordijk, J.

    2018-01-01

    Bacterial antimicrobial resistance (AMR) is constantly evolving and horizontal gene transfer through plasmids plays a major role. The identification of plasmid characteristics and their association with different bacterial hosts provides crucial knowledge that is essential to understand the

  14. A retrospective analysis of antimicrobial resistance in bacterial pathogens in an equine hospital (2012-2015).

    Science.gov (United States)

    van Spijk, J N; Schmitt, S; Fürst, A E; Schoster, A

    2016-06-01

    Antimicrobial resistance has become an important concern in veterinary medicine. The aim of this study was to describe the rate of antimicrobial resistance in common equine pathogens and to determine the occurrence of multidrug-resistant isolates. A retrospective analysis of all susceptibility testing results from bacterial pathogens cultured from horses at the University of Zurich Equine Hospital (2012-2015) was performed. Strains exhibiting resistance to 3 or more antimicrobial categories were defined as multidrug-resistant. Susceptibility results from 303 bacterial pathogens were analyzed, most commonly Escherichia coli (60/303, 20%) and Staphylococcus aureus (40/303, 13%). High rates of acquired resistance against commonly used antimicrobials were found in most of the frequently isolated equine pathogens. The highest rate of multidrug resistance was found in isolates of Acinetobacter baumannii (23/24, 96%), followed by Enterobacter cloacae complex (24/28, 86%) and Escherichia coli (48/60, 80%). Overall, 60% of Escherichia coli isolates were phenotypically ESBL-producing and 68% of Staphylococcus spp. were phenotypically methicillin-resistant. High rates of acquired antimicrobial resistance towards commonly used antibiotics are concerning and underline the importance of individual bacteriological and antimicrobial susceptibility testing to guide antimicrobial therapy. Minimizing and optimizing antimicrobial therapy in horses is needed.

  15. Occurrence of antimicrobial resistance among bacterial pathogens

    OpenAIRE

    Hendriksen, Rene S.; Mevius, Dik J.; Schroeter, Andreas; Teale, Christopher; Jouy, Eric; Butaye, Patrick; Franco, Alessia; Utinane, Andra; Amado, Alice; Moreno, Miguel; Greko, Christina; Stärk, Katharina D.C.; Berghold, Christian; Myllyniemi, Anna-Liisa; Hoszowski, Andrzej

    2008-01-01

    Background: The project "Antibiotic resistance in bacteria of animal origin – II" (ARBAO-II) was funded by the European Union (FAIR5-QLK2-2002-01146) for the period 2003–05. The aim of this project was to establish a program for the continuous monitoring of antimicrobial susceptibility of pathogenic and indicator bacteria from food animals using validated and harmonised methodologies. In this report the first data on the occurrence of antimicrobial resistance among bacteria cau...

  16. Phenotypic and genetic heterogeneity within biofilms with particular emphasis on persistence and antimicrobial tolerance.

    Science.gov (United States)

    Sadiq, Faizan A; Flint, Steve; Li, YanJun; Ou, Kai; Yuan, Lei; He, Guo Qing

    2017-09-01

    Phenotypic changes or phase variation within biofilms is an important feature of bacterial dormant life. Enhanced resistance to antimicrobials is one of the distinct features displayed by a fraction of cells within biofilms. It is believed that persisters are mainly responsible for this phenotypic heterogeneity. However, there is still an unresolved debate on the formation of persisters. In this short review, we highlight all known genomic and proteomic changes encountered by bacterial cells within biofilms. We have also described all phenotypic changes displayed by bacterial cells within biofilms with particular emphasis on enhanced antimicrobial tolerance of biofilms with particular reference to persisters. In addition, all currently known models of persistence have been succinctly discussed.

  17. Antimicrobial resistance in the environment

    National Research Council Canada - National Science Library

    Keen, Patricia L; Montforts, M. H. M. M

    2012-01-01

    .... Recognizing the connectivity between overlapping complex systems, the book discusses the subject from the perspective of an ecosystem approach"-- "This book explores the role that antimicrobial...

  18. Antimicrobial Resistance in Urine and Skin Isolates in Timor-Leste.

    Science.gov (United States)

    Marr, Ian; Sarmento, Nevio; O'Brien, Matt; Lee, Karl; Gusmao, Celia; de Castro, Gloria; Janson, Sonja; Tong, Steven Y C; Baird, Rob W; Francis, Joshua R

    2017-12-22

    High rates of antimicrobial resistance are seen throughout Southeast Asia. Limited antimicrobial resistance data exists for Timor-Leste, which is situated on the south-eastern portion of the Malay Archipelago. The purpose of this study was to identify antimicrobial resistance in bacteria isolated from urine and skin swabs from patients in Dili, Timor-Leste. Urine and skin swabs were collected from symptomatic patients and processed for bacterial culture in Timor-Leste. Isolates were processed in Australia using VITEK ® 2 (bioMerieux, France) for bacterial identification and to determine antimicrobial susceptibility according to CLSI standards. A total of 154 urine isolates and 57 skin isolates were analysed. Of the Enterobacteriaceae, 35% were resistant to ceftriaxone with an extended spectrum beta-lactamase producing phenotype. Carbapenem resistance was not found in any of the Gram-negative isolates. Of the Staphylococcus aureus isolates, 11% were of the community-acquired methicillin resistant S. aureus phenotype. A moderately high proportion of Gram negative urine isolates in Timor-Leste demonstrate phenotypic extended spectrum beta-lactamase production; and a relatively low proportion of S. aureus isolates are methicillin-resistant. Improved understanding of antimicrobial resistance rates in Timor-Leste can help guide antimicrobial prescribing and inform antimicrobial stewardship strategies. Copyright © 2017. Published by Elsevier Ltd.

  19. Whole-Genome Sequencing and Concordance Between Antimicrobial Susceptibility Genotypes and Phenotypes of Bacterial Isolates Associated with Bovine Respiratory Disease

    Directory of Open Access Journals (Sweden)

    Joseph R. Owen

    2017-09-01

    Full Text Available Extended laboratory culture and antimicrobial susceptibility testing timelines hinder rapid species identification and susceptibility profiling of bacterial pathogens associated with bovine respiratory disease, the most prevalent cause of cattle mortality in the United States. Whole-genome sequencing offers a culture-independent alternative to current bacterial identification methods, but requires a library of bacterial reference genomes for comparison. To contribute new bacterial genome assemblies and evaluate genetic diversity and variation in antimicrobial resistance genotypes, whole-genome sequencing was performed on bovine respiratory disease–associated bacterial isolates (Histophilus somni, Mycoplasma bovis, Mannheimia haemolytica, and Pasteurella multocida from dairy and beef cattle. One hundred genomically distinct assemblies were added to the NCBI database, doubling the available genomic sequences for these four species. Computer-based methods identified 11 predicted antimicrobial resistance genes in three species, with none being detected in M. bovis. While computer-based analysis can identify antibiotic resistance genes within whole-genome sequences (genotype, it may not predict the actual antimicrobial resistance observed in a living organism (phenotype. Antimicrobial susceptibility testing on 64 H. somni, M. haemolytica, and P. multocida isolates had an overall concordance rate between genotype and phenotypic resistance to the associated class of antimicrobials of 72.7% (P < 0.001, showing substantial discordance. Concordance rates varied greatly among different antimicrobial, antibiotic resistance gene, and bacterial species combinations. This suggests that antimicrobial susceptibility phenotypes are needed to complement genomically predicted antibiotic resistance gene genotypes to better understand how the presence of antibiotic resistance genes within a given bacterial species could potentially impact optimal bovine respiratory

  20. Identification of acquired antimicrobial resistance genes

    DEFF Research Database (Denmark)

    Zankari, Ea; Hasman, Henrik; Cosentino, Salvatore

    2012-01-01

    ObjectivesIdentification of antimicrobial resistance genes is important for understanding the underlying mechanisms and the epidemiology of antimicrobial resistance. As the costs of whole-genome sequencing (WGS) continue to decline, it becomes increasingly available in routine diagnostic laborato......ObjectivesIdentification of antimicrobial resistance genes is important for understanding the underlying mechanisms and the epidemiology of antimicrobial resistance. As the costs of whole-genome sequencing (WGS) continue to decline, it becomes increasingly available in routine diagnostic...... laboratories and is anticipated to substitute traditional methods for resistance gene identification. Thus, the current challenge is to extract the relevant information from the large amount of generated data.MethodsWe developed a web-based method, ResFinder that uses BLAST for identification of acquired...... 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...

  1. Danish integrated antimicrobial in resistance monitoring and research program

    DEFF Research Database (Denmark)

    Hammerum, Anette Marie; Heuer, Ole Eske; Emborg, Hanne-Dorthe

    2007-01-01

    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......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...... 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....

  2. Rapid electrochemical phenotypic profiling of antibiotic-resistant bacteria.

    Science.gov (United States)

    Besant, Justin D; Sargent, Edward H; Kelley, Shana O

    2015-07-07

    Rapid phenotyping of bacteria to identify drug-resistant strains is an important capability for the treatment and management of infectious disease. At present, the rapid determination of antibiotic susceptibility is hindered by the requirement that, in existing devices, bacteria must be pre-cultured for 2-3 days to reach detectable levels. Here we report a novel electrochemical approach that achieves rapid readout of the antibiotic susceptibility profile of a bacterial infection within one hour. The electrochemical reduction of a redox-active molecule is monitored that reports on levels of metabolically-active bacteria. Bacteria are captured in miniaturized wells, incubated with antimicrobials and monitored for resistance. This electrochemical phenotyping approach is effective with clinically-relevant levels of bacteria, and provides results comparable to culture-based analysis. Results, however, are delivered on a much faster timescale, with resistance profiles available after a one hour incubation period.

  3. Bacterial Resistance to the Tetracyclines and Antimicrobial ...

    African Journals Online (AJOL)

    Optimizing of tetracycline antibiotics dosing and duration in human and animal healthcare and food production might help minimize the emergence of resistance in some situations. New approaches to antimicrobial chemotherapy are needed if we are to survive the increasing rates of tetracycline antibiotic resistance ...

  4. Molecular Methods for Detection of Antimicrobial Resistance

    DEFF Research Database (Denmark)

    Anjum, Muna F.; Zankari, Ea; Hasman, Henrik

    2017-01-01

    The increase in bacteria harboring antimicrobial resistance (AMR) is a global problem because there is a paucity of antibiotics available to treat multidrug-resistant bacterial infections in humans and animals. Detection of AMR present in bacteria that may pose a threat to veterinary and public...

  5. Widespread acquisition of antimicrobial resistance among Campylobacter isolates from UK retail poultry and evidence for clonal expansion of resistant lineages.

    Science.gov (United States)

    Wimalarathna, Helen M L; Richardson, Judith F; Lawson, Andy J; Elson, Richard; Meldrum, Richard; Little, Christine L; Maiden, Martin C J; McCarthy, Noel D; Sheppard, Samuel K

    2013-07-15

    Antimicrobial resistance is increasing among clinical Campylobacter cases and is common among isolates from other sources, specifically retail poultry - a major source of human infection. In this study the antimicrobial susceptibility of isolates from a UK-wide survey of Campylobacter in retail poultry in 2001 and 2004-5 was investigated. The occurrence of phenotypes resistant to tetracycline, quinolones (ciprofloxacin and naladixic acid), erythromycin, chloramphenicol and aminoglycosides was quantified. This was compared with a phylogeny for these isolates based upon Multi Locus Sequence Typing (MLST) to investigate the pattern of antimicrobial resistance acquisition. Antimicrobial resistance was present in all lineage clusters, but statistical testing showed a non-random distribution. Erythromycin resistance was associated with Campylobacter coli. For all antimicrobials tested, resistant isolates were distributed among relatively distant lineages indicative of widespread acquisition. There was also evidence of clustering of resistance phenotypes within lineages; indicative of local expansion of resistant strains. These results are consistent with the widespread acquisition of antimicrobial resistance among chicken associated Campylobacter isolates, either through mutation or horizontal gene transfer, and the expansion of these lineages as a proportion of the population. As Campylobacter are not known to multiply outside of the host and long-term carriage in humans is extremely infrequent in industrialized countries, the most likely location for the proliferation of resistant lineages is in farmed chickens.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    Michael, Carolyn Anne; Dominey-Howes, Dale; Labbate, Maurizio

    2014-01-01

    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 among 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; and (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 program 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.

  8. Antimicrobial-resistant Shigella infections from Iran

    DEFF Research Database (Denmark)

    Tajbakhsh, Mercedeh; García Migura, Lourdes; Rahbar, Mohammad

    2012-01-01

    Objectives: In this study, we wanted to assess the level of antimicrobial resistance, the presence of genes encoding resistance to cephalosporins and plasmid-mediated quinolone resistance (PMQR), and genetic relatedness among Shigella isolates obtained from Iranian patients. ; Methods: A total....... ; Results: Of the isolates, 25 (68%) were S. sonnei phase II, with 5 (14%) S. flexneri, 5 (14%) Shigella dysenteriae type 2, and 2 (5%) Shigella boydii type 2. Resistance to at least threeclasses of antimicrobials was detected in all species. The presence of blaCTX-M-15 and the AmpC β-lactamase producer bla...... Shigella flexneri type 1b) were examined for the presence of genes encoding cephalosporin resistance. The presence of PMQR was assessed in one S. flexneri isolate exhibiting low-level resistance to ciprofloxacin and susceptibility to nalidixic acid. PFGE was performed on 25 S. sonnei phase II isolates...

  9. 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.

  10. Bacterial strategies of resistance to antimicrobial peptides.

    Science.gov (United States)

    Joo, Hwang-Soo; Fu, Chih-Iung; Otto, Michael

    2016-05-26

    Antimicrobial peptides (AMPs) are a key component of the host's innate immune system, targeting invasive and colonizing bacteria. For successful survival and colonization of the host, bacteria have a series of mechanisms to interfere with AMP activity, and AMP resistance is intimately connected with the virulence potential of bacterial pathogens. In particular, because AMPs are considered as potential novel antimicrobial drugs, it is vital to understand bacterial AMP resistance mechanisms. This review gives a comparative overview of Gram-positive and Gram-negative bacterial strategies of resistance to various AMPs, such as repulsion or sequestration by bacterial surface structures, alteration of membrane charge or fluidity, degradation and removal by efflux pumps.This article is part of the themed issue 'Evolutionary ecology of arthropod antimicrobial peptides'. © 2016 The Author(s).

  11. Antimicrobial and disinfectant resistance of Escherichia coli isolated from giant pandas.

    Science.gov (United States)

    Guo, L; Long, M; Huang, Y; Wu, G; Deng, W; Yang, X; Li, B; Meng, Y; Cheng, L; Fan, L; Zhang, H; Zou, L

    2015-07-01

    The study aims to demonstrate the antimicrobial and disinfectant resistance phenotypes and genotypes of Escherichia coli isolates obtained from giant pandas (Ailuropoda melanoleuca). Antimicrobial testing was performed according to the standard disk diffusion method. The minimal inhibitory concentrations (MICs) of disinfectants were determined using the agar dilution method. All isolates were screened for the presence of antimicrobial and disinfectant resistance genes and further analysed for genetic relatedness by pulse-field gel electrophoresis (PFGE). Results showed that 46·6% of the isolates were resistant to at least one antimicrobial. Escherichia coli isolates showed resistance to fewer antimicrobials as panda age increased. Among antimicrobial-resistant E. coli isolates, the antimicrobial resistance genes blaCTX-M (88·2%) and sul1 (92·3%) were most prevalent. The disinfectant resistance genes emrE, ydgE/ydgF, mdfA and sugE(c) were commonly present (68·2-98·9%), whereas qac and sugE(p) were relatively less prevalent (0-21·3%). The frequencies of resistance genes tended to be higher in E. coli isolated in December than in July, and PFGE profiles were also more diverse in isolates in December. The qacEΔ1 and sugE(p) genes were higher in adolescent pandas than in any other age groups. PFGE revealed that antimicrobial resistance correlated well with sampling time and habitat. This study demonstrated that antimicrobial and disinfectant resistance was common in giant panda-derived E. coli, and the antimicrobial resistance was associated with sampling time and habitat. Escherichia coli could serve as a critical vector in spreading disinfectant and antimicrobial resistance. This is the first study that demonstrated the phenotypic and genetic characterizations of antimicrobial and disinfectant resistance in E. coli isolates from more than 60 giant pandas. Frequent transfer of pandas to other cages may lead to the dissemination of antimicrobial resistance. The

  12. Comparison of antimicrobial resistance patterns in enterococci from intensive and free range chickens in Australia.

    Science.gov (United States)

    Obeng, Akua Serwaah; Rickard, Heather; Ndi, Olasumbo; Sexton, Margaret; Barton, Mary

    2013-02-01

    Resistance to antimicrobials in enterococci from poultry has been found throughout the world and is generally recognized as associated with antimicrobial use. This study was conducted to evaluate the phenotypic and genotypic profile of enterococcal isolates of intensive (indoor) and free range chickens from 2008/09 and 2000 in order to determine the patterns of antimicrobial resistance associated with different management systems. The minimum inhibitory concentrations in faecal enterococci isolates were determined by agar dilution. Resistance to bacitracin, ceftiofur, erythromycin, lincomycin, tylosin and tetracycline was more common among meat chickens (free range and intensive) than free range egg layers (Pfree range meat chickens.

  13. Antimicrobial resistance in campylobacter: susceptibility testing methods and resistance trends.

    Science.gov (United States)

    Ge, Beilei; Wang, Fei; Sjölund-Karlsson, Maria; McDermott, Patrick F

    2013-10-01

    Most Campylobacter infections are self-limiting but antimicrobial treatment (e.g., macrolides, fluoroquinolones) is necessary in severe or prolonged cases. Susceptibility testing continues to play a critical role in guiding therapy and epidemiological monitoring of resistance. The methods of choice for Campylobacter recommended by the Clinical and Laboratory Standards Institute (CLSI) are agar dilution and broth microdilution, while a disk diffusion method was recently standardized by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Macrolides, quinolones, and tetracyclines are among the common antimicrobials recommended for testing. Molecular determination of Campylobacter resistance via DNA sequencing or PCR-based methods has been performed. High levels of resistance to tetracycline and ciprofloxacin are frequently reported by many national surveillance programs, but resistance to erythromycin and gentamicin in Campylobacter jejuni remains low. Nonetheless, variations in susceptibility observed over time underscore the need for continued public health monitoring of Campylobacter resistance from humans, animals, and food. Published by Elsevier B.V.

  14. 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

    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

  15. 76 FR 16795 - The National Antimicrobial Resistance Monitoring System Strategic Plan 2011-2015; Request for...

    Science.gov (United States)

    2011-03-25

    ...] The National Antimicrobial Resistance Monitoring System Strategic Plan 2011-2015; Request for Comments..., FDA requested comments on a document for the National Antimicrobial Resistance Monitoring System....fda.gov/AnimalVeterinary/SafetyHealth/AntimicrobialResistance/NationalAntimicrobialResistance...

  16. Antimicrobial resistance determinants among anaerobic bacteria isolated from footrot.

    Science.gov (United States)

    Lorenzo, María; García, Nuria; Ayala, Juan Alfonso; Vadillo, Santiago; Píriz, Segundo; Quesada, Alberto

    2012-05-25

    Antibiotic resistance has been evaluated among 36 Gram negative and anaerobic bacilli (10 Bacteroides, 11 Prevotella, 7 Porphyromonas and 8 Fusobacterium strains) isolated from clinical cases of caprine and ovine footrot (necrotic pododermatitis). The initial analysis on this bacterial consortium evaluates the relationships existing among antimicrobial resistance determinants, phenotype expression and mobilization potential. The Bacteroides strains were generally resistant to penicillins, first-generation cephalosporins, tetracycline and erythromycin, and expressed low level of β-lactamase activity. The main determinants found among the Bacteroides strains were cepA and tetQ genes, conferring resistance to β-lactams and tetracycline, respectively. A general susceptibility to β-lactams was shown for most Prevotella, Porphyromonas and Fusobacterium strains, where none of the β-lactamase genes described in Bacteroides was detected. Resistance to tetracycline and/or erythromycin was found among the three bacterial groups. Although tetQ genes were detected for several Prevotella and Porphyromonas strains, a unique ermF positive was revealed among Prevotella strains. The expression of resistance markers was not related with the polymorphism of their coding sequences. However, the finding of sequence signatures for conjugative transposons in the vicinities of tetQ and ermF suggests a mobilization potential that might have contributed to the spread of antimicrobial resistance genes. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Prevalence and genetic mechanisms of antimicrobial resistance in Staphylococcus species: A multicentre report of the indian council of medical research antimicrobial resistance surveillance network

    Directory of Open Access Journals (Sweden)

    Sunanda Rajkumar

    2017-01-01

    Full Text Available Purpose: Routine surveillance of antimicrobial resistance (AMR is an essential component of measures aimed to tackle the growing threat of resistant microbes in public health. This study presents a 1-year multicentre report on AMR in Staphylococcus species as part of Indian Council of Medical Research-AMR surveillance network. Materials and Methods: Staphylococcus species was routinely collected in the nodal and regional centres of the network and antimicrobial susceptibility testing was performed against a panel of antimicrobials. Minimum inhibitory concentration (MIC values of vancomycin (VAN, daptomycin, tigecycline and linezolid (LNZ against selected methicillin-resistant Staphylococcus aureus(MRSA isolates were determined by E-test and MIC creep, if any, was determined. Resistant genotypes were determined by polymerase chain reaction for those isolates showing phenotypic resistance. Results: The prevalence of MRSA was found to be range from moderate (21% to high (45% among the centres with an overall prevalence of 37.3%. High prevalence of resistance was observed with commonly used antimicrobials such as ciprofloxacin and erythromycin in all the centres. Resistance to LNZ was not encountered except for a single case. Full-blown resistance to VAN in S. aureus was not observed; however, a few VAN-intermediate S. aureus isolates were documented. The most common species of coagulase negative staphylococci (CoNS identified was Staphylococcus haemolyticus and Staphylococcus epidermidis. Resistance among CoNS was relatively higher than S. aureus. Most phenotypically resistant organisms possessed the corresponding resistance genes. Conclusion: There were localised differences in the prevalence of resistance between the centres. The efficacy of the anti-MRSA antimicrobials was very high; however, almost all these antimicrobials showed evidence of creeping MIC.

  18. Antimicrobial resistant coagulase positive Staphylococcus aureus ...

    African Journals Online (AJOL)

    ADEYEYE

    ISSN 2315-6201). Suleiman/Sokoto Journal of Veterinary Sciences (2013). 11(1): 51-55. http://dx.doi.org/10.4314/sokjvs.v11i1.8. Antimicrobial resistant coagulase positive Staphylococcus aureus from chickens in Maiduguri,Nigeria. A Suleiman.

  19. Campylobacter Antimicrobial Drug Resistance among Humans in ...

    African Journals Online (AJOL)

    Background: Though Campylobacter enteritis is a self-limiting disease, antimicrobial agents are recommended for extraintestinal infections and for treating immunocompromised persons. Erythromycin and ciprofloxacin are drugs of choice. The rate of resistance to these drugs is increasing in both developed and developing ...

  20. Antimicrobial resistant bacteria in the food chain

    DEFF Research Database (Denmark)

    Wegener, Henrik Caspar

    2003-01-01

    to fluoroquinolones, which are used for empirical treatment of diarrhea in humans. Resistance to vancomycin and Synercid((R)) in enterococci is associated with use of similar drugs as growth promoters in food animals. Danish food animal producers have terminated the use of antimicrobial growth promoters. This has...

  1. Prevalence and antimicrobial resistance pattern of coagulase ...

    African Journals Online (AJOL)

    Prevalence and antimicrobial resistance pattern of coagulase negative Staphylococci isolated from pigs and in-contact humans in Jos Metropolis, Nigeria. ... (53/401) of the isolates were CoNS species based on confirmatory test with Microgen biochemical kit and were further subjected to antibiotic susceptibility testing.

  2. Relation between antimicrobial use and resistance in Belgian pig herds

    OpenAIRE

    Callens, Benedicte; Boyen, Filip; Maes, Dominiek; Haesebrouck, Freddy; Butaye, Patrick; Dewulf, Jeroen

    2011-01-01

    The aim of this study was to determine the link between the characteristics of antimicrobial therapy and occurrence of antimicrobial resistance in Escherichia coli of clinically healthy pigs exposed to antimicrobial treatments. A total of 918 Escherichia coli isolates were obtained from faecal samples, collected from 50 pig herds at the end of the fattening period and susceptibility was tested towards 15 different antimicrobial agents, using the disk diffusion method. The Antimicrobial Resist...

  3. Cationic antimicrobial peptide resistance mechanisms of streptococcal pathogens.

    Science.gov (United States)

    LaRock, Christopher N; Nizet, Victor

    2015-11-01

    Cationic antimicrobial peptides (CAMPs) are critical front line contributors to host defense against invasive bacterial infection. These immune factors have direct killing activity toward microbes, but many pathogens are able to resist their effects. Group A Streptococcus, group B Streptococcus and Streptococcus pneumoniae are among the most common pathogens of humans and display a variety of phenotypic adaptations to resist CAMPs. Common themes of CAMP resistance mechanisms among the pathogenic streptococci are repulsion, sequestration, export, and destruction. Each pathogen has a different array of CAMP-resistant mechanisms, with invasive disease potential reflecting the utilization of several mechanisms that may act in synergy. Here we discuss recent progress in identifying the sources of CAMP resistance in the medically important Streptococcus genus. Further study of these mechanisms can contribute to our understanding of streptococcal pathogenesis, and may provide new therapeutic targets for therapy and disease prevention. This article is part of a Special Issue entitled: Bacterial Resistance to Antimicrobial Peptides. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Integrating tuberculosis and antimicrobial resistance control programmes.

    Science.gov (United States)

    Hasan, Rumina; Shakoor, Sadia; Hanefeld, Johanna; Khan, Mishal

    2018-03-01

    Many low- and middle-income countries facing high levels of antimicrobial resistance, and the associated morbidity from ineffective treatment, also have a high burden of tuberculosis. Over recent decades many countries have developed effective laboratory and information systems for tuberculosis control. In this paper we describe how existing tuberculosis laboratory systems can be expanded to accommodate antimicrobial resistance functions. We show how such expansion in services may benefit tuberculosis case-finding and laboratory capacity through integration of laboratory services. We further summarize the synergies between high-level strategies on tuberculosis and antimicrobial resistance control. These provide a potential platform for the integration of programmes and illustrate how integration at the health-service delivery level for diagnostic services could occur in practice in a low- and middle-income setting. Many potential mutual benefits of integration exist, in terms of accelerated scale-up of diagnostic testing towards rational use of antimicrobial drugs as well as optimal use of resources and sharing of experience. Integration of vertical disease programmes with separate funding streams is not without challenges, however, and we also discuss barriers to integration and identify opportunities and incentives to overcome these.

  5. Antimicrobial Peptides: A Promising Therapeutic Strategy in Tackling Antimicrobial Resistance.

    Science.gov (United States)

    Nuti, Ramya; Goud, Nerella S; Saraswati, A Prasanth; Alvala, Ravi; Alvala, Mallika

    2017-01-01

    Antimicrobial resistance (AMR) has posed a serious threat to global public health and it requires immediate action, preferably long term. Current drug therapies have failed to curb this menace due to the ability of microbes to circumvent the mechanisms through which the drugs act. From the drug discovery point of view, the majority of drugs currently employed for antimicrobial therapy are small molecules. Recent trends reveal a surge in the use of peptides as drug candidates as they offer remarkable advantages over small molecules. Newer synthetic strategies like organometalic complexes, Peptide-polymer conjugates, solid phase, liquid phase and recombinant DNA technology encouraging the use of peptides as therapeutic agents with a host of chemical functions, and tailored for specific applications. In the last decade, many peptide based drugs have been successfully approved by the Food and Drug Administration (FDA). This success can be attributed to their high specificity, selectivity and efficacy, high penetrability into the tissues, less immunogenicity and less tissue accumulation. Considering the enormity of AMR, the use of Antimicrobial Peptides (AMPs) can be a viable alternative to current therapeutics strategies. AMPs are naturally abundant allowing synthetic chemists to develop semi-synthetics peptide molecules. AMPs have a broad spectrum of activity towards microbes and they possess the ability to bypass the resistance induction mechanisms of microbes. The present review focuses on the potential applications of AMPs against various microbial disorders and their future prospects. Several resistance mechanisms and their strategies have also been discussed to highlight the importance in the current scenario. Breakthroughs in AMP designing, peptide synthesis and biotechnology have shown promise in tackling this challenge and has revived the interest of using AMPs as an important weapon in fighting AMR. Copyright© Bentham Science Publishers; For any queries

  6. 75 FR 16817 - 2010 Scientific Meeting of the National Antimicrobial Resistance Monitoring System; Public...

    Science.gov (United States)

    2010-04-02

    ... Scientific Meeting of the National Antimicrobial Resistance Monitoring System; Public Meeting; Request for... Meeting of the National Antimicrobial Resistance Monitoring System.'' The topic to be discussed is the results from the National Antimicrobial Resistance Monitoring System (NARMS) and related antimicrobial...

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

    Directory of Open Access Journals (Sweden)

    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.

  8. ANTIMICROBIAL RESISTANCE AND ITS GLOBAL SPREAD

    Directory of Open Access Journals (Sweden)

    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

  9. Coagulase-Positive Staphylococcus: Prevalence and Antimicrobial Resistance.

    Science.gov (United States)

    Beça, Nuno; Bessa, Lucinda Janete; Mendes, Ângelo; Santos, Joana; Leite-Martins, Liliana; Matos, Augusto J F; da Costa, Paulo Martins

    2015-01-01

    Staphylococcus pseudintermedius is the most prevalent coagulase-positive Staphylococcus inhabitant of the skin and mucosa of dogs and cats, causing skin and soft tissue infections in these animals. In this study, coagulase-positive Staphylococcus species were isolated from companion animals, veterinary professionals, and objects from a clinical veterinary environment by using two particular culture media, Baird-Parker RPF agar and CHROMagar Staph aureus. Different morphology features of colonies on the media allowed the identification of the species, which was confirmed by performing a multiplex polymerase chain reaction (PCR). Among 23 animals, 15 (65.2%) harbored coagulase-positive Staphylococcus, being 12 Staphylococcus pseudintermedius carriers. Four out of 12 were methicillin-resistant S. pseudintermedius (MRSP). All veterinary professionals had coagulase-positive Staphylococcus (CoPS) species on their hands and two out of nine objects sampled harbored MRSP. The antimicrobial-resistance pattern was achieved for all isolates, revealing the presence of many multidrug-resistant CoPS, particularly S. pseudintermedius . The combined analysis of the antimicrobial-resistance patterns shown by the isolates led to the hypothesis that there is a possible crosscontamination and dissemination of S. aureus and S. pseudintermedius species between the three types of carriers sampled in this study that could facilitate the spread of the methicillin-resistance phenotype.

  10. Antimicrobial Susceptibility/Resistance of Streptococcus Pneumoniae

    Science.gov (United States)

    Karcic, Emina; Aljicevic, Mufida; Bektas, Sabaheta; Karcic, Bekir

    2015-01-01

    Introduction: Pneumococcal infections are a major cause of morbidity and mortality worldwide, whose treatment is threatened with an increase in the number of strains resistant to antibiotic therapy. Goal: The main goal of this research was to investigate the presence of antimicrobial susceptibility/resistance of S. pneumoniae. Material and methods: Taken are swabs of the nose and nasopharynx, eye and ear. In vitro tests that were made in order to study the antimicrobial resistance of pneumococci are: disk diffusion method and E-test. Results: The resistance to inhibitors of cell wall synthesis was recorded at 39.17%, protein synthesis inhibitors 19.67%, folate antagonists 47.78% and quinolone in 1.11%. S. pneumoniae has shown drug resistance to erythromycin in 45%, clindamycin in 45%, chloramphenicol–0.56%, rifampicin–6.11%, tetracycline–4.67%, penicillin-G in 4.44%, oxacillin in 73.89%, ciprofloxacin in 1.11% and trimethoprim-sulfamethoxazole in 5.34% of cases. Conclusion: The highest resistance pneumococcus showed to erythromycin, clindamycin and trimethoprim-sulfamethoxazole and these should be avoided in the treatment. The least resistance pneumococcus showed to tetracycline, rifampicin, chloramphenicol, penicillin-G and ciprofloxacin. PMID:26236165

  11. 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

  12. Impact of antimicrobial use during beef production on fecal occurrence of antimicrobial resistance

    Science.gov (United States)

    Objective: To determine the impact of typical antimicrobial use during cattle production on fecal occurrence of antimicrobial resistance by culture, quantitative PCR, and metagenomic sequencing. Experimental Design & Analysis: Feces were recovered from colons of 36 lots of "conventional" (CONV) ca...

  13. Antimicrobial resistance, heavy metal resistance and integron content in bacteria isolated from a South African tilapia aquaculture system.

    Science.gov (United States)

    Chenia, Hafizah Y; Jacobs, Anelet

    2017-11-21

    Antibacterial compounds and metals co-select for antimicrobial resistance when bacteria harbour resistance genes towards both types of compounds, facilitating the proliferation and evolution of antimicrobial and heavy metal resistance. Antimicrobial and heavy metal resistance indices of 42 Gram-negative bacteria from a tilapia aquaculture system were determined to identify possible correlations between these phenotypes. Agar dilution assays were carried out to determine susceptibility to cadmium, copper, lead, mercury, chromate and zinc, while susceptibility to 21 antimicrobial agents was investigated by disk diffusion assays. Presence of merA, the mercury resistance gene, was determined by dot-blot hybridizations and PCR. Association of mercury resistance with integrons and transposon Tn21 was also investigated by PCR. Isolates displayed a high frequency of antimicrobial (erythromycin: 100%; ampicillin: 85%; trimethoprim: 78%) and heavy metal (Zn2+: 95%; Cd2+: 91%) resistance. No correlation was established between heavy metal and multiple antibiotic resistance indices. Significant positive correlations were observed between heavy metal resistance profiles, indices, Cu2+ and Cr3+ resistance with erythromycin resistance. Significant positive correlations were observed between merA (24%)/Tn21 (24%) presence and heavy metal resistance profiles and indices; however, significant negative correlations were obtained between integron-associated qacE∆1 (43%) and sulI (26%) gene presence and heavy metal resistance indices. Heavy metal and antimicrobial agents co-select for resistance, with fish-associated, resistant bacteria demonstrating simultaneous heavy metal resistance. Thus, care should be taken when using anti-fouling heavy metals as feed additives in aquaculture facilities.

  14. Marine echinoderms as reservoirs of antimicrobial resistant bacteria

    Directory of Open Access Journals (Sweden)

    Catarina Marinho

    2014-06-01

    (Marinho et al., 2013. Erythromycin and tetracycline are widely used in human therapy, and this may have contributed to the increasing resistance to these antibiotics (Hummel et al., 2007, Barros et al., 2011. It also highlights the lack of antibiotic efficiency in medicine, doing with resistance dissemination. Also, several genes associated with antimicrobial resistance were already found in antimicrobial-resistant enterococci from echinoderms: tet(M/tet(L, erm(A/erm(B, vat(D/vat(E, aac(6’-aph(2'' and aph(3'-IIIa genes were detected in tetracycline, erythromycin, quinupristin-dalfopristin, gentamicin and kanamycin-resistant isolates, respectively (Marinho et al., 2013. Despite of the small number of Escherichia coli isolates from echinoderms samples, they displayed an antibiotic-resistant phenotype to: tetracycline, streptomycin, tobramycin and amoxicillin + clavulanic acid. E. coli isolates from echinoderms tetracycline-resistant had tet(A and tet(B genes present in their genome. Besides, the aadA gene was detected in all E. coli streptomycin-resistant strains isolated from echinoderms (Marinho et al., 2013. According to some results, enterococci and E. coli displaying phenotype and resistance genes to some antibiotics that were already documented in marine animals, humans, wastewaters and numerous wildlife animals (Marinho et al., 2013, Barros et al., 2011, Sousa et al., 2011, Foti et al., 2009. Echinoderms are coastal animals and, consequently, it is possible that sewage discharges at the ocean may represent the main source of antibiotic-resistant bacteria deriving from several habitats. Indirect effects in micro-systems from the antibiotic disturbance are largely unknown; however, it is expected that such disorder might have significant long-term effects on the rate and stability of the ecosystem. Nevertheless, the consumption of exotic food is an example of a potential pathway for human contact with marine echinoderms microbiota, which may contain antibiotic-resistant

  15. The growing problem of antimicrobial resistance

    DEFF Research Database (Denmark)

    Holmstrup, Palle; Klausen, Bjarne

    2018-01-01

    Antibiotic therapy over the years has saved millions of lives, but antimicrobial resistance (AMR) is a current threat to human health. An interesting review on AMR has recently been presented in the Journal of American Medical Association (Marston et al., 2016). The review is authored by five staff...... members at National Institutes of Health in Bethesda, Maryland, and the purpose of the review was to identify factors associated with AMR, the current epidemiology of important resistant organisms, and possible solutions to the AMR problem. This article is protected by copyright. All rights reserved....

  16. 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...

  17. Shigella Antimicrobial Drug Resistance Mechanisms, 2004-2014.

    Science.gov (United States)

    Nüesch-Inderbinen, Magdalena; Heini, Nicole; Zurfluh, Katrin; Althaus, Denise; Hächler, Herbert; Stephan, Roger

    2016-06-01

    To determine antimicrobial drug resistance mechanisms of Shigella spp., we analyzed 344 isolates collected in Switzerland during 2004-2014. Overall, 78.5% of isolates were multidrug resistant; 10.5% were ciprofloxacin resistant; and 2% harbored mph(A), a plasmid-mediated gene that confers reduced susceptibility to azithromycin, a last-resort antimicrobial agent for shigellosis.

  18. 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. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Antimicrobial resistance in Danish pigs: A cross sectional study of the association between antimicrobial resistance and geography, exposure to antimicrobials, and trade

    DEFF Research Database (Denmark)

    Birkegård, Anna Camilla

    the risk of human pathogens becoming resistant. Pigs might constitute an important reservoir. Therefore, it is important to manage antimicrobial resistance in pigs. Before effectiveactions can be initiated, it is crucial to know which factors are associated with the levels of antimicrobial resistance...... the collection of information on relevant factors. The aim of this PhD project was to study the relationship between the levels of antimicrobial resistance genes and three factors in Danish pig farms: the geographical location of the farm, the exposure to antimicrobials, and the trade patterns. Data collection......-randomness in the spatial distribution. One of the aims of this PhD project was to estimate the quantitative relationship between the antimicrobial resistance gene levels and antimicrobial exposure. Previous studies have indicated that antimicrobial exposure in early periods of a pig’s life can influence the antimicrobial...

  20. Antimicrobial resistance genes in Actinobacillus pleuropneumoniae, Haemophilus parasuis and Pasteurella multocida isolated from Australian pigs.

    Science.gov (United States)

    Dayao, Dae; Gibson, J S; Blackall, P J; Turni, C

    2016-07-01

    To identify genes associated with the observed antimicrobial resistance in Actinobacillus pleuropneumoniae, Haemophilus parasuis and Pasteurella multocida isolated from Australian pigs. Isolates with known phenotypic resistance to β-lactams, macrolides and tetracycline were screened for the presence of antimicrobial resistance genes. A total of 68 A. pleuropneumoniae, 62 H. parasuis and 20 P. multocida isolates exhibiting phenotypic antimicrobial resistance (A. pleuropneumoniae and P. multocida) or elevated minimal inhibitory concentrations (MICs) (H. parasuis) to any of the following antimicrobial agents - ampicillin, erythromycin, penicillin, tetracycline, tilmicosin and tulathromycin - were screened for a total of 19 associated antimicrobial resistance genes (ARGs) by PCR. The gene bla ROB-1 was found in all ampicillin- and penicillin-resistant isolates, but none harboured the bla TEM-1 gene. The tetB gene was found in 76% (74/97) of tetracycline-resistant isolates, 49/53 A. pleuropneumoniae, 17/30 H. parasuis and 8/14 P. multocida. One A. pleuropneumoniae isolate harboured the tetH gene, but none of the 97 isolates had tetA, tetC, tetD, tetE, tetL, tetM or tetO. A total of 92 isolates were screened for the presence of macrolide resistance genes. None was found to have ermA, ermB, ermC, erm42, mphE, mefA, msrA or msrE. The current study has provided a genetic explanation for the resistance or elevated MIC of the majority of isolates of Australian porcine respiratory pathogens to ampicillin, penicillin and tetracycline. However, the macrolide resistance observed by phenotypic testing remains genetically unexplained and further studies are required. © 2016 Australian Veterinary Association.

  1. Population mobility, globalization, and antimicrobial drug resistance.

    Science.gov (United States)

    MacPherson, Douglas W; Gushulak, Brian D; Baine, William B; Bala, Shukal; Gubbins, Paul O; Holtom, Paul; Segarra-Newnham, Marisel

    2009-11-01

    Population mobility is a main factor in globalization of public health threats and risks, specifically distribution of antimicrobial drug-resistant organisms. Drug resistance is a major risk in healthcare settings and is emerging as a problem in community-acquired infections. Traditional health policy approaches have focused on diseases of global public health significance such as tuberculosis, yellow fever, and cholera; however, new diseases and resistant organisms challenge existing approaches. Clinical implications and health policy challenges associated with movement of persons across barriers permeable to products, pathogens, and toxins (e.g., geopolitical borders, patient care environments) are complex. Outcomes are complicated by high numbers of persons who move across disparate and diverse settings of disease threat and risk. Existing policies and processes lack design and capacity to prevent or mitigate adverse health outcomes. We propose an approach to global public health risk management that integrates population factors with effective and timely application of policies and processes.

  2. Diversity and Antimicrobial Resistance Genotypes in Non-Typhoidal Salmonella Isolates from Poultry Farms in Uganda

    Directory of Open Access Journals (Sweden)

    Terence Odoch

    2018-02-01

    Full Text Available Non-typhoidal Salmonella (NTS are foodborne pathogens of global public health significance. The aim of this study was to subtype a collection of 85 NTS originating from poultry farms in Uganda, and to evaluate a subgroup of phenotypically resistant isolates for common antimicrobial resistance genes and associated integrons. All isolates were subtyped by pulsed-field gel electrophoresis (PFGE. Phenotypically resistant isolates (n = 54 were screened by PCR for the most relevant AMR genes corresponding to their phenotypic resistance pattern, and all 54 isolates were screened by PCR for the presence of integron class 1 and 2 encoding genes. These genes are known to commonly encode resistance to ampicillin, tetracycline, ciprofloxacin, trimethoprim, sulfonamide and chloramphenicol. PFGE revealed 15 pulsotypes representing 11 serotypes from 75 isolates, as 10 were non-typable. Thirty one (57.4% of the 54 resistant isolates carried at least one of the seven genes (blaTEM-1, cmlA, tetA, qnrS, sul1, dhfrI, dhfrVII identified by PCR and six (11% carried class 1 integrons. This study has shown that a diversity of NTS-clones are present in Ugandan poultry farm settings, while at the same time similar NTS-clones occur in different farms and areas. The presence of resistance genes to important antimicrobials used in human and veterinary medicine has been demonstrated, hence the need to strengthen strategies to combat antimicrobial resistance at all levels.

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

    Directory of Open Access Journals (Sweden)

    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

  4. Antimicrobial resistance problems in typhoid fever

    Science.gov (United States)

    Saragih, R. H.; Purba, G. C. F.

    2018-03-01

    Typhoid fever (enteric fever) remains a burden in developing countries and a major health problem in Southern and Southeastern Asia. Salmonella typhi (S. typhi), the causative agent of typhoid fever, is a gram-negative, motile, rod-shaped, facultative anaerobe and solely a human pathogen with no animal reservoir. Infection of S. typhi can cause fever, abdominal pain and many worsenonspecific symptoms, including gastrointestinal symptoms suchas nausea, vomiting, constipation, and diarrhea. Chloramphenicol, ampicillin,and cotrimoxazole were the first-recommended antibiotics in treating typhoid fever. In the last two decades though, these three traditional drugs started to show resistance and developed multidrug resistance (MDR) S. typhi strains. In many parts of the world, the changing modes ofpresentation and the development of MDR have made typhoid fever increasingly difficult to treat.The use of first-line antimicrobials had been recommended to be fluoroquinolone as a replacement. However, this wassoonfollowedbyreportsof isolates ofS. typhi showing resistancetofluoroquinolones as well. These antimicrobial resistance problems in typhoid fever have been an alarming situation ever since and need to be taken seriously or else typhoid fever will no longer be taken care completely by administering antibiotics.

  5. Antimicrobial Resistance Trend of Bacteria from Clinical Isolates: An ...

    African Journals Online (AJOL)

    For decades, antimicrobials have proven useful for the treatment of bacterial infections. However, the immergence of antimicrobial resistance has become a major challenge to public health in many countries. The aim of this study was to investigate the antimicrobial susceptibility of bacterial isolates from clinical sources.

  6. Antimicrobial use in swine production and its effect on the swine gut microbiota and antimicrobial resistance.

    Science.gov (United States)

    Holman, Devin B; Chénier, Martin R

    2015-11-01

    Antimicrobials have been used in swine production at subtherapeutic levels since the early 1950s to increase feed efficiency and promote growth. In North America, a number of antimicrobials are available for use in swine. However, the continuous administration of subtherapeutic, low concentrations of antimicrobials to pigs also provides selective pressure for antimicrobial-resistant bacteria and resistance determinants. For this reason, subtherapeutic antimicrobial use in livestock remains a source of controversy and concern. The swine gut microbiota demonstrates a number of changes in response to antimicrobial administration depending on the dosage, duration of treatment, age of the pigs, and gut location that is sampled. Both culture-independent and -dependent studies have also shown that the swine gut microbiota contains a large number of antimicrobial resistance determinants even in the absence of antimicrobial exposure. Heavy metals, such as zinc and copper, which are often added at relatively high doses to swine feed, may also play a role in maintaining antimicrobial resistance and in the stability of the swine gut microbiota. This review focuses on the use of antimicrobials in swine production, with an emphasis on the North American regulatory context, and their effect on the swine gut microbiota and on antimicrobial resistance determinants in the gut microbiota.

  7. 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 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...... species, genes conferring antimicrobial resistance were observed with the following frequencies: bla TEM, 40.7%; bla CMY-2, 15.2%; bla CTX-M, 11.5%; sul2, 27.2%; sul1, 14.4%; tet(A), 5.4%;tet(L), 5.4%; tet(M), 5.0%; tet(E), 3.7%; tet(C), 3.3%; tet(S), 2.5%; and tet(K), 0.8%. Various antimicrobial...

  8. Antimicrobial resistance in Swiss laying hens, prevalence and risk factors.

    Science.gov (United States)

    Harisberger, M; Gobeli, S; Hoop, R; Dewulf, J; Perreten, V; Regula, G

    2011-09-01

    Antimicrobial resistance is an emerging concern to public health, and food-producing animals are known to be a potential source for transmission of resistant bacteria to humans. As legislation of the European Union requires to ban conventional cages for the housing of laying hens on the one hand, and a high food safety standard for eggs on the other hand, further investigations about the occurrence of antimicrobial resistance in alternative housing types are required. In this study, we determined antimicrobial resistance in indicator bacteria from 396 cloacal swabs from 99 Swiss laying hen farms among four alternative housing types during a cross-sectional study. On each farm, four hens were sampled and exposure to potential risk factors was identified with a questionnaire. The minimal inhibitory concentration was determined using broth microdilution in Escherichia coli (n=371) for 18 antimicrobials and in Enterococcus faecalis (n=138) and Enterococcus faecium (n=153) for 16 antimicrobials. All antimicrobial classes recommended by the European Food Safety Authority for E. coli and enterococci were included in the resistance profile. Sixty per cent of the E. coli isolates were susceptible to all of the considered antimicrobials and 30% were resistant to at least two antimicrobials. In E. faecalis, 33% of the strains were susceptible to all tested antimicrobials and 40% were resistant to two or more antimicrobials, whereas in E. faecium these figures were 14% and 39% respectively. Risk factor analyses were carried out for bacteria species and antimicrobials with a prevalence of resistance between 15% and 85%. In these analyses, none of the considered housing and management factors showed a consistent association with the prevalence of resistance for more than two combinations of bacteria and antimicrobial. Therefore we conclude that the impact of the considered housing and management practices on the egg producing farms on resistance in laying hens is low. © 2010

  9. Antimicrobial resistance and its association with tolerance to heavy metals in agriculture production.

    Science.gov (United States)

    Yu, Zhongyi; Gunn, Lynda; Wall, Patrick; Fanning, Séamus

    2017-06-01

    Antimicrobial resistance is a recognized public health challenge that since its emergence limits the therapeutic options available to veterinarians and clinicians alike, when treatment is warranted. This development is further compounded by the paucity of new antibiotics. The agri-food industry benefits from the availability of antimicrobial compounds for food-animal production and crop protection. Nonetheless, their improper use can result in the selection for bacteria that are phenotypically resistant to these compounds. Another class of agents used in agriculture includes various cationic metals that can be included in animal diets as nutritional supplements or spread on pastures to support crop growth and protection. Heavy metals, in particular, are giving rise to concerns among public health professionals, as they can persist in the environment remaining stable for prolonged periods. Moreover, bacteria can also exhibit resistance to these chemical elements and the genes encoding this phenotype can be physically localized to plasmids that may also contain one or more antimicrobial resistance-encoding gene(s). This paper reviews our current understanding of the role that bacteria play in expressing resistance to heavy metals. It will describe how heavy metals are used in agri-food production, and explore evidence available to link resistance to heavy metals and antimicrobial compounds. In addition, possible solutions to reduce the impact of heavy metal resistance are also discussed, including using organic minerals and reducing the level of trace minerals in animal feed rations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Genetic elements associated with antimicrobial resistance among avian pathogenic Escherichia coli

    Directory of Open Access Journals (Sweden)

    Amal Awad

    2016-11-01

    Full Text Available Abstract Background Avian-pathogenic Escherichia coli (APEC are pathogenic strains of E. coli that are responsible for one of the most predominant bacterial disease affecting poultry worldwide called avian colibacillosis. This study describes the genetic determinants implicated in antimicrobial resistance among APEC isolated from different broiler farms in Egypt. Methods A total of 116 APEC were investigated by serotyping, antimicrobial resistance patterns to 10 antimicrobials, and the genetic mechanisms underlying the antimicrobial-resistant phenotypes. Results Antibiogram results showed that the highest resistance was observed for ampicillin, tetracycline, nalidixic acid, and chloramphenicol. The detected carriage rate of integron was 29.3% (34/116. Further characterization of gene cassettes revealed the presence gene cassettes encoding resistance to trimethoprim (dfrA1, dfrA5, dfrA7, dfrA12, streptomycin/spectinomycin (aadA1, aadA2, aadA5, aadA23, and streptothricin (sat2. To our knowledge, this the first description of the presence of aadA23 in APEC isolates. Analysis of other antimicrobial resistance types not associated with integrons revealed the predominance of resistance genes encoding resistance to tetracycline (tetA and tetB, ampicillin (bla TEM, chloramphenicol (cat1, kanamycin (aphA1, and sulphonamide (sul1 and sul2. Among ciprofloxacin-resistant isolates, the S83L mutation was the most frequently substitution observed in the quinolone resistance-determining region of gyrA (56.3%. The bla TEM and bla CTX−M−1 genes were the most prevalent among APEC isolates producing extended-spectrum beta-lactamase (ESβL. Conclusions These findings provided important clues about the role of integron-mediated resistance genes together with other independent resistance genes and chromosomal mutations in shaping the epidemiology of antimicrobial resistance in E. coli isolates from poultry farms in Egypt.

  11. Genetic elements associated with antimicrobial resistance among avian pathogenic Escherichia coli.

    Science.gov (United States)

    Awad, Amal; Arafat, Nagah; Elhadidy, Mohamed

    2016-11-25

    Avian-pathogenic Escherichia coli (APEC) are pathogenic strains of E. coli that are responsible for one of the most predominant bacterial disease affecting poultry worldwide called avian colibacillosis. This study describes the genetic determinants implicated in antimicrobial resistance among APEC isolated from different broiler farms in Egypt. A total of 116 APEC were investigated by serotyping, antimicrobial resistance patterns to 10 antimicrobials, and the genetic mechanisms underlying the antimicrobial-resistant phenotypes. Antibiogram results showed that the highest resistance was observed for ampicillin, tetracycline, nalidixic acid, and chloramphenicol. The detected carriage rate of integron was 29.3% (34/116). Further characterization of gene cassettes revealed the presence gene cassettes encoding resistance to trimethoprim (dfrA1, dfrA5, dfrA7, dfrA12), streptomycin/spectinomycin (aadA1, aadA2, aadA5, aadA23), and streptothricin (sat2). To our knowledge, this the first description of the presence of aadA23 in APEC isolates. Analysis of other antimicrobial resistance types not associated with integrons revealed the predominance of resistance genes encoding resistance to tetracycline (tetA and tetB), ampicillin (bla TEM ), chloramphenicol (cat1), kanamycin (aphA1), and sulphonamide (sul1 and sul2). Among ciprofloxacin-resistant isolates, the S83L mutation was the most frequently substitution observed in the quinolone resistance-determining region of gyrA (56.3%). The bla TEM and bla CTX-M-1 genes were the most prevalent among APEC isolates producing extended-spectrum beta-lactamase (ESβL). These findings provided important clues about the role of integron-mediated resistance genes together with other independent resistance genes and chromosomal mutations in shaping the epidemiology of antimicrobial resistance in E. coli isolates from poultry farms in Egypt.

  12. Antimicrobial resistance in Campylobacter spp. isolated from Ontario sheep flocks and associations between antimicrobial use and antimicrobial resistance.

    Science.gov (United States)

    Scott, L; Menzies, P; Reid-Smith, R J; Avery, B P; McEwen, S A; Moon, C S; Berke, O

    2012-06-01

    The objectives of this study were to determine the prevalence of antimicrobial resistance (AMR) in faecal Campylobacter spp. from lambs and adult sheep and associations between antimicrobial use (AMU) and AMR. A total of 275 faecal samples collected during initial and final visits from 51 sheep flocks, including one feedlot, across southern Ontario were tested for the presence of Campylobacter spp. Campylobacter jejuni was detected in 52% (143/275) of the faecal samples, Campylobacter coli in 7% (19/275), Campylobacter lari in 1% (2/275) and 2% (4/275) were non-speciated Campylobacter. Broth microdilution was used to test antimicrobial susceptibility of 162 isolates to nine antimicrobials. Campylobacter jejuni isolates (n = 142) were resistant to tetracycline (39%), ciprofloxacin (4%), nalidixic acid (4%) and telithromycin (1%). C. coli isolates (n = 19) were resistant to tetracycline (74%), and azithromycin, clindamycin, erythromycin, and telithromycin (5%). The C. lari isolate displayed resistance to nalidixic acid. No statistically significant associations were found between AMU and AMR during multivariate modelling in this study. © 2012 Blackwell Verlag GmbH.

  13. 76 FR 37356 - 2011 Scientific Meeting of the National Antimicrobial Resistance Monitoring System; Public...

    Science.gov (United States)

    2011-06-27

    ...] 2011 Scientific Meeting of the National Antimicrobial Resistance Monitoring System; Public Meeting... Scientific Meeting of the National Antimicrobial Resistance Monitoring System.'' The topic to be discussed is animal and retail sampling methods for the National Antimicrobial Resistance Monitoring System (NARMS...

  14. Refugees and antimicrobial resistance: A systematic review.

    Science.gov (United States)

    de Smalen, Allard Willem; Ghorab, Hatem; Abd El Ghany, Moataz; Hill-Cawthorne, Grant A

    There is a large increase in the numbers of refugees and asylum seekers worldwide and a lack of data on the carriage of antimicrobial resistance in refugee/asylum seeking groups. This article aims to identify the impact of refugees and asylum seekers on the acquisition and transmission of antimicrobial resistance (AMR) through a literature search. The databases Embase, Medline, Pubmed, and Web of Science Core Collection were utilised and covered all articles before the 1st of October 2016. In total, 577 articles were identified, and studies were eligible if they met the selection criteria, including observational study design, English language, and AMR strains reported in absolute numbers. In total, 17 articles met the criteria, the majority were from the European region. Articles fitting the selection criteria exclusively reported AMR in bacterial species including Mycobacterium tuberculosis, Escherichia coli, Klebsiella pneumonia, K. oxytoca, Shigella spp., Staphylococcus aureus, Enterococcus faecium, and Acinetobacter baumannii. The analyses indicated that a high percentage of AMR strains, have been circulating among refugees and asylum seekers. The displacement of refugees and asylum seekers seem to play a key role in the transmission of AMR. Therefore, improved AMR control measures are essential. A knowledge gap was identified; further research is strongly recommended. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. 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.

  16. Heavy metals in liquid pig manure in light of bacterial antimicrobial resistance

    International Nuclear Information System (INIS)

    Hölzel, Christina S.; Müller, Christa; Harms, Katrin S.; Mikolajewski, Sabine; Schäfer, Stefanie; Schwaiger, Karin; Bauer, Johann

    2012-01-01

    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.

  17. Providing context: antimicrobial resistance from multiple environmental sources

    Science.gov (United States)

    Background: Animal agriculture has been identified as encouraging the spread of resistance due to the use of large quantities of antimicrobials for animal production purposes. When antimicrobial resistance (AMR) is reported in agricultural settings without comparison to other environments there is a...

  18. Plasmid profile and antimicrobial resistance ratings of enterococci ...

    African Journals Online (AJOL)

    Our aim was to isolate and investigate the resistance ratings of enterococci poultry and pig isolates to various antimicrobial agents as well as to determine their plasmid profiles. Antimicrobial resistance ratings and the plasmid profiles of Enterococci isolated from poultry birds and pigs were analyzed. Three hundred and ...

  19. Multiple antimicrobial-resistant Salmonella serotypes isolated from ...

    African Journals Online (AJOL)

    Background: Antimicrobial-resistant Salmonella and other zoonotic bacterial pathogens can be transferred from animals to humans through consumption of contaminated food and food products and thus present a public health risk. The increase in Salmonella resistance to the commonly used antimicrobials both in the ...

  20. Antimicrobial resistance of gram-negative aerobic bacteria isolates ...

    African Journals Online (AJOL)

    The increasing incidence of antimicrobial resistance in pathogenic and commensal Gram-negative bacteria from dogs has continued to raise concerns in veterinary small animal practice and public health. In this study, antimicrobial resistance was investigated in Gram-negative aerobic bacteria isolated from the faeces of ...

  1. Antimicrobial resistance among Brazilian Corynebacterium diphtheriae strains

    Directory of Open Access Journals (Sweden)

    Gabriela Andrade Pereira

    2008-08-01

    Full Text Available The increasing problems with multidrug resistance in relation to Corynebacterium, including C. diphtheriae, are examples of challenges confronting many countries. For this reason, Brazilian C. diphtheriae strains were evaluated by the E-Test for their susceptibility to nine antibacterial drugs used in therapy. Resistance (MIC < 0.002; 0.38 µg/ml to penicillin G was found in 14.8% of the strains tested. Although erythromycin (MIC90 0.75 µg/ml and azithromycin (MIC90 0.064 µg/ml were active against C. diphtheriae in this study, 4.2% of the strains showed decreased susceptibility (MIC 1.0 µg/ml to erythromycin. Multiple resistance profiles were determined by the disk diffusion method using 31 antibiotics. Most C. diphtheriae strains (95.74% showed resistance to mupirocin, aztreonam, ceftazidime, and/or oxacillin, ampicillin, penicillin, tetracycline, clindamycin, lincomycin, and erythromycin. This study presents the antimicrobial susceptibility profiles of Brazilian C. diphtheriae isolates. The data are of value to practitioners, and suggest that some concern exists regarding the use of penicillin.

  2. Cyclodextrins: A Weapon in the Fight Against Antimicrobial Resistance

    Science.gov (United States)

    Wong, Chew Ee; Dolzhenko, Anton V.; Lee, Sui Mae; Young, David James

    Antimicrobial resistance poses one of the most serious global challenges of our age. Cyclodextrins (CDs) are widely utilized excipients in formulations because of their solubilizing properties, low toxicity, and low inflammatory response. This review summarizes recent investigations of antimicrobial agents involving CDs and CD-based antimicrobial materials. CDs have been employed for antimicrobial applications either through formation of inclusion complexes or by chemical modification of their hydroxyl groups to tailor pharmaceutically active compounds. Applications of these CD inclusion complexes include drug delivery, antimicrobial coatings on materials (e.g., biomedical devices and implants) and antimicrobial dressings that help to prevent wound infections. There are relatively limited studies of chemically modified CDs with antimicrobial activity. The mechanism of action of antimicrobial CD inclusion complexes and derivatives needs further elucidation, but activity of CDs and their derivatives is often associated with their interaction with bacterial cell membranes.

  3. Phenotypic and Genotypic Antibiotic Resistance of Salmonella from Chicken Carcasses Marketed at Ibague, Colombia

    Directory of Open Access Journals (Sweden)

    D Cortes Vélez

    Full Text Available ABSTRACT Salmonella enterica is responsible for alimentary toxic infections associated with the consumption of contaminated poultry products and the antimicrobial resistant patterns of Salmonella circulating in the Tolima region are currently unknown. To address this issue, both the phenotype and genotype antibiotic resistance patterns of 47 Salmonella isolated from raw chicken carcasses sold at the Ibague city were analyzed by the disc diffusion, microdilution and PCR assays. All 47 Salmonella isolates showed resistance to five or more antimicrobial agents. Resistance to Ampicillin (AMP, Amikacin (AMK, Gentamicin (GEN, Tobramycin (TOB, Cefazoline (CFZ, Cefoxitin (FOX, Nitrofurantoin (NIT, Trimethoprim-Sulfamethoxazole (SXT, Tetracycline (TET, Ciprofloxacin (CIP and Enrofloxacin (ENR was observed in 42.35% of Salmonella isolates. All tested S. Paratyphi B var Java isolates showed resistance to at least 12 antibiotics. S. Hvittingfoss showed resistance to 5 antibiotics, whereas S. Muenster showed resistance to seven antibiotics. Amplification of a number of antibiotic resistance genes showed that blaTEM (100% correlated well with resistance to Ampicilin and Cephalosporin, whereas aadB (87% correlated well with resistance to Aminoglycosides. It is concluded that Salmonella isolated from raw chicken meat marketed at Ibague showed MDR by both phenotypic and genotypic methods and they may represent an important threat to human health. Additional studies are needed to establish the relationship between antibiotic resistance in Salmonella from poultry products and clinical isolates.

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

    Directory of Open Access Journals (Sweden)

    Alejandro H Buschmann

    Full Text Available 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.

  5. 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. PMID:22905164

  6. 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.

  7. Antimicrobial resistance in the 21st century: a multifaceted challenge.

    Science.gov (United States)

    Nolte, O

    2014-04-01

    Antimicrobial resistance, the ability of (pathogenic) bacteria to withstand the action of antibiotic drugs, has recently been rated of having an impact on humans similar to that of global climate change. Indeed, during the last years medicine has faced the development of highly resistant bacterial strains, which were, as a consequence of worldwide travel activity, dispersed all over the globe. This is even more astonishing if taking into account that antibiotics were introduced into human medicine not even hundred years ago. Resistance covers different principle aspects, natural resistance, acquired resistance and clinical resistance. In the modern microbiology laboratory, antimicrobial resistance is determined by measuring the susceptibility of micro-organisms in vitro in the presence of antimicrobials. However, since the efficacy of an antibiotic depends on its pharmacokinetic and pharmacodynamics properties, breakpoints are provided to translate minimal inhibitory concentration to categorical efficacy (i.e. susceptible or resistant). Resistance in one microorganism against one particular drug may drive treatment decisions of clinicians, thereby fostering selection pressure to resistance development against another antibiotic. Thereby, bacteria may acquire more and more resistance traits, ending up with multi-resistance. To this end, antimicrobial resistance becomes a public health concern, not only in terms of limited treatment options but also due to its economic burden. The current paper provides a summary of the main topics associated with antimicrobial resistance as an introduction to this special issue.

  8. Public health risk of antimicrobial resistance transfer from companion animals.

    Science.gov (United States)

    Pomba, Constança; Rantala, Merja; Greko, Christina; Baptiste, Keith Edward; Catry, Boudewijn; van Duijkeren, Engeline; Mateus, Ana; Moreno, Miguel A; Pyörälä, Satu; Ružauskas, Modestas; Sanders, Pascal; Teale, Christopher; Threlfall, E John; Kunsagi, Zoltan; Torren-Edo, Jordi; Jukes, Helen; Törneke, Karolina

    2017-04-01

    Antimicrobials are important tools for the therapy of infectious bacterial diseases in companion animals. Loss of efficacy of antimicrobial substances can seriously compromise animal health and welfare. A need for the development of new antimicrobials for the therapy of multiresistant infections, particularly those caused by Gram-negative bacteria, has been acknowledged in human medicine and a future corresponding need in veterinary medicine is expected. A unique aspect related to antimicrobial resistance and risk of resistance transfer in companion animals is their close contact with humans. This creates opportunities for interspecies transmission of resistant bacteria. Yet, the current knowledge of this field is limited and no risk assessment is performed when approving new veterinary antimicrobials. The objective of this review is to summarize the current knowledge on the use and indications for antimicrobials in companion animals, drug-resistant bacteria of concern among companion animals, risk factors for colonization of companion animals with resistant bacteria and transmission of antimicrobial resistance (bacteria and/or resistance determinants) between animals and humans. The major antimicrobial resistance microbiological hazards originating from companion animals that directly or indirectly may cause adverse health effects in humans are MRSA, methicillin-resistant Staphylococcus pseudintermedius, VRE, ESBL- or carbapenemase-producing Enterobacteriaceae and Gram-negative bacteria. In the face of the previously recognized microbiological hazards, a risk assessment tool could be applied in applications for marketing authorization for medicinal products for companion animals. This would allow the approval of new veterinary medicinal antimicrobials for which risk levels are estimated as acceptable for public health. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For

  9. Genomic and functional techniques to mine the microbiome for novel antimicrobials and antimicrobial resistance genes.

    Science.gov (United States)

    Adu-Oppong, Boahemaa; Gasparrini, Andrew J; Dantas, Gautam

    2017-01-01

    Microbial communities contain diverse bacteria that play important roles in every environment. Advances in sequencing and computational methodologies over the past decades have illuminated the phylogenetic and functional diversity of microbial communities from diverse habitats. Among the activities encoded in microbiomes are the abilities to synthesize and resist small molecules, yielding antimicrobial activity. These functions are of particular interest when viewed in light of the public health emergency posed by the increase in clinical antimicrobial resistance and the dwindling antimicrobial discovery and approval pipeline, and given the intimate ecological and evolutionary relationship between antimicrobial biosynthesis and resistance. Here, we review genomic and functional methods that have been developed for accessing the antimicrobial biosynthesis and resistance capacity of microbiomes and highlight outstanding examples of their applications. © 2016 New York Academy of Sciences.

  10. Dealing with antimicrobial resistance - the Danish experience

    DEFF Research Database (Denmark)

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

    2000-01-01

    as possible and ultimately abolished. During the first half of the 1990s the consumption of tetracyclines, mainly in pig production, increased markedly. This was countered by severely reducing through legal means the financial enticement for veterinarians to prescribe medicines and by restricting...... (DANMAP), which monitors resistance among bacteria from food animals, food and humans. A programme to monitor all use of prescription medicine in food animals at the herd level is presently being implemented. Another initiative was the elaboration of a series of practical recommendations to veterinarians...... 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...

  11. The antimicrobial resistance crisis: management through gene monitoring

    Science.gov (United States)

    2016-01-01

    Antimicrobial resistance (AMR) is an acknowledged crisis for humanity. Its genetic origins and dire potential outcomes are increasingly well understood. However, diagnostic techniques for monitoring the crisis are currently largely limited to enumerating the increasing incidence of resistant pathogens. Being the end-stage of the evolutionary process that produces antimicrobial resistant pathogens, these measurements, while diagnostic, are not prognostic, and so are not optimal in managing this crisis. A better test is required. Here, using insights from an understanding of evolutionary processes ruling the changing abundance of genes under selective pressure, we suggest a predictive framework for the AMR crisis. We then discuss the likely progression of resistance for both existing and prospective antimicrobial therapies. Finally, we suggest that by the environmental monitoring of resistance gene frequency, resistance may be detected and tracked presumptively, and how this tool may be used to guide decision-making in the local and global use of antimicrobials. PMID:27831476

  12. Antimicrobial resistance, virulence, and phylogenetic characteristics of Escherichia coli isolates from clinically healthy swine.

    Science.gov (United States)

    Lay, Khin Khin; Koowattananukul, Chailai; Chansong, Nisit; Chuanchuen, Rungtip

    2012-11-01

    A total of 344 commensal Escherichia coli isolates from clinically healthy pigs were examined for antimicrobial resistance phenotypes, class 1 integrons, resistance genes, virulence gene profile, and phylogenetic groups. The majority of E. coli isolates were resistant to tetracycline (96.2%) and ampicillin (91.6%). Up to 98% were multidrug resistant. Seventy-three percent of the isolates carried class 1 integrons. Inserted-gene cassette arrays in variable regions included incomplete sat, aadA22, aadA1, dfrA12-aadA2, and sat-psp-aadA2, of which the aadA2 gene cassette was most prevalent (42.9%). Horizontal transfer was detected in eight E. coli isolates carrying class 1 integrons with dfrA12-aadA2 gene cassette array. Sixteen resistance genes were identified among the E. coli isolates with corresponding resistance phenotype. Ten virulence genes (including elt, estA, estB, astA, faeG, fasA, fedA, eaeA, paa, and sepA) were detected, of which fasA was most commonly found (98.3%). Most of the E. coli isolates belonged to phylogenetic group B1. Significantly positive associations were observed between some virulence genes and some resistance phenotypes and genotypes (p antimicrobial resistance-encoding genes and virulence determinants.

  13. Experimental evolution of resistance to an antimicrobial peptide

    OpenAIRE

    Perron, Gabriel G; Zasloff, Michael; Bell, Graham

    2005-01-01

    A novel class of antibiotics based on the antimicrobial properties of immune peptides of multicellular organisms is attracting increasing interest as a major weapon against resistant microbes. It has been claimed that cationic antimicrobial peptides exploit fundamental features of the bacterial cell so that resistance is much less likely to evolve than in the case of conventional antibiotics. Population models of the evolutionary genetics of resistance have cast doubt on this claim. We docume...

  14. Emergence of Antimicrobial-Resistant Escherichia coli of Animal Origin Spreading in Humans

    Science.gov (United States)

    Skurnik, David; Clermont, Olivier; Guillard, Thomas; Launay, Adrien; Danilchanka, Olga; Pons, Stéphanie; Diancourt, Laure; Lebreton, François; Kadlec, Kristina; Roux, Damien; Jiang, Deming; Dion, Sara; Aschard, Hugues; Denamur, Maurice; Cywes-Bentley, Colette; Schwarz, Stefan; Tenaillon, Olivier; Andremont, Antoine; Picard, Bertrand; Mekalanos, John; Brisse, Sylvain; Denamur, Erick

    2016-01-01

    In the context of the great concern about the impact of human activities on the environment, we studied 403 commensal Escherichia coli/Escherichia clade strains isolated from several animal and human populations that have variable contacts to one another. Multilocus sequence typing (MLST) showed a decrease of diversity 1) in strains isolated from animals that had an increasing contact with humans and 2) in all strains that had increased antimicrobial resistance. A specific B1 phylogroup clonal complex (CC87, Institut Pasteur schema nomenclature) of animal origin was identified and characterized as being responsible for the increased antimicrobial resistance prevalence observed in strains from the environments with a high human-mediated antimicrobial pressure. CC87 strains have a high capacity of acquiring and disseminating resistance genes with specific metabolic and genetic determinants as demonstrated by high-throughput sequencing and phenotyping. They are good mouse gut colonizers but are not virulent. Our data confirm the predominant role of human activities in the emergence of antimicrobial resistance in the environmental bacterial strains and unveil a particular E. coli clonal complex of animal origin capable of spreading antimicrobial resistance to other members of microbial communities. PMID:26613786

  15. Association between selected antimicrobial resistance genes and antimicrobial exposure in Danish pig farms

    DEFF Research Database (Denmark)

    Birkegård, Anna Camilla; Hisham Beshara Halasa, Tariq; Græsbøll, Kaare

    2017-01-01

    Bacterial antimicrobial resistance (AMR) in pigs is an important public health concern due to its possible transfer to humans. We aimed at quantifying the relationship between the lifetime exposure of antimicrobials and seven antimicrobial resistance genes in Danish slaughter pig farms. AMR gene...... levels were quantified by qPCR of total-community DNA in faecal samples obtained from 681 batches of slaughter pigs. The lifetime exposure to antimicrobials was estimated at batch level for the piglet, weaner, and finisher periods individually for the sampled batches. We showed that the effect...... of antimicrobial exposure on the levels of AMR genes was complex and unique for each individual gene. Several antimicrobial classes had both negative and positive correlations with the AMR genes. From 10-42% of the variation in AMR gene levels could be explained in the final regression models, indicating...

  16. Characteristic diversity and antimicrobial resistance of Salmonella from gastroenteritis.

    Science.gov (United States)

    Luo, Yunchun; Yi, Wen; Yao, Yuzhou; Zhu, Ni; Qin, Pengfei

    2018-04-01

    Salmonella is a leading cause of foodborne disease worldwide and may cause to gastroenteritis. The aim of this study was to determine the prevalence, serotypes, virulence genes, molecular subtyping, and antibiotic resistance phenotype of Salmonella from gastroenteritis in Hubei, China. Of 500 patients stools samples collected from January 2015 to January 2016, 52 (10.40%) samples were contaminated by Salmonella. The results showed that most of the isolates were positive for eight virulence genes that appear on pathogenicity islands, prophages, plasmid, and fimbrial. A total of twelve serotypes were found. Antimicrobial susceptibility results indicated that most strains were resistant to ampicillin (57.69%), kanamycin (53.85%), and tetracycline (40.38%). There were 33 STs on MLST types, and were grouped into two clusters. Thus, our findings provided insights into the dissemination of antibiotic resistant strains, genetic diversity, and improved our knowledge of microbiological risk assessment in Salmonella from gastroenteritis. Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  17. Refractory versus resistant hypertension: Novel distinctive phenotypes

    Science.gov (United States)

    Dudenbostel, Tanja; Siddiqui, Mohammed; Gharpure, Nitin; Calhoun, David A.

    2017-01-01

    Resistant hypertension (RHTN) is relatively common with an estimated prevalence of 10-20% of treated hypertensive patients. It is defined as blood pressure (BP) >140/90 mmHg treated with ≥3 antihypertensive medications, including a diuretic, if tolerated. Refractory hypertension is a novel phenotype of severe antihypertensive treatment failure. The proposed definition for refractory hypertension, i.e. BP >140/90 mmHg with use of ≥5 different antihypertensive medications, including a diuretic and a mineralocorticoid receptor antagonist (MRA) has been applied inconsistently. In comparison to RHTN, refractory hypertension seems to be less prevalent than RHTN. This review focuses on current knowledge about this novel phenotype compared with RHTN including definition, prevalence, mechanisms, characteristics and comorbidities, including cardiovascular risk. In patients with RHTN excess fluid retention is thought to be a common mechanism for the development of RHTN. Recently, evidence has emerged suggesting that refractory hypertension may be more of neurogenic etiology due to increased sympathetic activity as opposed to excess fluid retention. Treatment recommendations for RHTN are generally based on use and intensification of diuretic therapy, especially with the combination of a long-acting thiazide-like diuretic and an MRA. Based on findings from available studies, such an approach does not seem to be a successful strategy to control BP in patients with refractory hypertension and effective sympathetic inhibition in such patients, either with medications and/or device based approaches may be needed. PMID:29034321

  18. 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.

  19. Resistencia bacteriana Bacterial resistance to antimicrobial agents

    Directory of Open Access Journals (Sweden)

    Jesualdo Fuentes

    1993-01-01

    Full Text Available

    Se presenta un panorama de la resistencia bacteriana incluyendo su fisiopatogenia y formas de presentación y se establecen algunas consideraciones generales de tipo clínico como auxiliares para racionalizar el uso de los antimicrobianos y evitar o retardar el problema de la resistencia; éste plantea la necesidad de un reordenamiento definitivo en la prescripción de antimicrobianos. No será tanto la creación o descubrimiento de nuevos antibióticos sino la racionalización del manejo de los existentes lo que permitirá alcanzar victorias sobre estos microorganismos. Es Importante mantener educación continua sobre el uso adecuado de los antimicrobianos desde los puntos de vista epidemiológico, farmacocinético y fisiopatogénico.

    An overview on bacterial resistance to antimicrobial agents is presented. It includes the different genetic mechanisms for Its development and the biochemical phenomena that explain It. Some clinical considerations are proposed in order to rationalize the use of these drugs and to avoid or delay the appearance of resistance.

  20. Correlation of molecular resistance mechanisms and phenotypic resistance levels in streptomycin-resistant Mycobacterium tuberculosis.

    OpenAIRE

    Meier, A; Sander, P; Schaper, K J; Scholz, M; Böttger, E C

    1996-01-01

    Quantitative susceptibility testing of clinical isolates of streptomycin-resistant Mycobacterium tuberculosis demonstrated that there is a close correlation between the molecular resistance mechanism and the in vitro activity of streptomycin: mutations in rpsL were mainly associated with high-level resistance, mutations in rrs were associated with an intermediate level of resistance, and streptomycin-resistant isolates with wild-type rpsL and rrs exhibited a low-level resistance phenotype. In...

  1. Frequency and antimicrobial resistance of aerobic bacteria isolated ...

    African Journals Online (AJOL)

    This study was carried out to evaluate the frequency of occurrence and antimicrobial resistance of aerobic bacteria isolated from surgical sites in human and animal patients in Nsukka, southeast Nigeria. Wound swabs from 132 patients (96 humans and 36 animals) were cultured for bacterial isolation. Antimicrobial ...

  2. Acid resistance, bile tolerance and antimicrobial properties of ...

    African Journals Online (AJOL)

    Yomi

    2012-01-16

    Jan 16, 2012 ... antimicrobial activity against a broad spectrum of bacteria, including food spoilage and pathogenic organisms such ... Key words: Baobab seeds, maari, fermentation, lactic acid bacteria, acid resistance, bile tolerance, antimicrobial .... cells was estimated by microscope using a counting chamber. (Neubauer ...

  3. 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 pa...

  4. Antimicrobial resistance in aerobic bacteria isolated from oral ...

    African Journals Online (AJOL)

    This study reinforces the need for dog bite wound microbial culture and antimicrobial sensitivity test as isolates showed varied antimicrobial susceptibility patterns. The oral cavities of hunting dogs are laden with multi-drug resistant bacteria of significant public health importance that could be transferred to humans through ...

  5. 76 FR 4120 - The National Antimicrobial Resistance Monitoring System Strategic Plan 2011-2015; Request for...

    Science.gov (United States)

    2011-01-24

    ...] The National Antimicrobial Resistance Monitoring System Strategic Plan 2011-2015; Request for Comments... National Antimicrobial Resistance Monitoring System (NARMS) entitled ``NARMS Strategic Plan 2011-2015.../AntimicrobialResistance/NationalAntimicrobialResistanceMonitoringSystem/default.htm or http://www.regulations...

  6. Bacterial resistance to antimicrobial peptides: an evolving phenomenon.

    Science.gov (United States)

    Fleitas, Osmel; Agbale, Caleb M; Franco, Octavio L

    2016-06-01

    Bacterial resistance to conventional antibiotics is currently a real problem all over the world, making novel antimicrobial compounds a real research priority. Some of the most promising compounds found to date are antimicrobial peptides (AMPs). The benefits of these drugs include their broad spectrum of activity that affects several microbial processes, making the emergence of resistance less likely. However, bacterial resistance to AMPs is an evolving phenomenon that compromises the therapeutic potential of these compounds. Therefore, it is mandatory to understand bacterial mechanisms of resistance to AMPs in depth, in order to develop more powerful AMPs that overcome the bacterial resistance response.

  7. 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 corresponds...... to the amounts of antimicrobial agents used in food animal production in those countries. Similar genes were found to encode resistance in the different countries, but the tet(L) and let(S) genes were more frequently found among isolates from Spain. A recently identified transferable copper resistance gene...... was found in all copper-resistant isolates from the different countries....

  8. Antimicrobial Resistance among Enterococci from Pigs in Three European Countries

    Science.gov (United States)

    Aarestrup, Frank Møller; Hasman, Henrik; Jensen, Lars Bogø; Moreno, Miguel; Herrero, Inmaculada A.; Domínguez, Lucas; Finn, Maria; Franklin, Anders

    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 corresponds to the amounts of antimicrobial agents used in food animal production in those countries. Similar genes were found to encode resistance in the different countries, but the tet(L) and tet(S) genes were more frequently found among isolates from Spain. A recently identified transferable copper resistance gene was found in all copper-resistant isolates from the different countries. PMID:12147518

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

    Directory of Open Access Journals (Sweden)

    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.

  10. 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

    quantitative data on antimicrobial resistance (resistance prevalence per sample). Methods: In this study, a total of 98 faecal samples from slaughter pigs were tested for tetracycline and sulphonamide resistance in Escherichia coli using the single colony method, and these results were compared......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....

  11. Advances in pharmacovigilance initiatives surrounding antimicrobial resistance-Indian perspective.

    Science.gov (United States)

    Bairy, Laxminarayana Kurady; Nayak, Veena; A, Avinash; Kunder, Sushil Kiran

    2016-08-01

    In recent years the development of antimicrobial resistance has been accelerating, the discovery of new antimicrobial agents has slowed substantially in past decades. This review mainly focuses on the problem of antimicrobial resistance(AMR); the various contributor mechanisms, consequences and future of AMR. The review also highlights the irrational use of antimicrobials, improving their usage and problems associated with pharmacovigilance of antimicrobial resistance. Pharmacovigilance in the form of surveillance of antibiotic use is being done in 90% of the countries worldwide through the WHONET program developed by WHO. However, the data comes from a limited area of the globe. Data from every part of the world is required, so that there is geographical representation of every region. A major hurdle in quantifying the extent of antimicrobial resistance is the fact that there are several known microbes, that may turn out to be resistant to one or more of the several known antimicrobial agents. The global action plan initiated by WHO, if implemented successfully will definitely reduce AMR and will help in evaluating treatment interventions.

  12. 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.

  13. Antimicrobial resistance profiles in pathogens isolated from chickens

    Science.gov (United States)

    Antimicrobial resistance profiles are frequently studied from the perspective of epidemiology and not so often from the perspective of population genetics. The population geneticist assumes that gene flow, vertically (generation to generation), horizontally (individual to individual) or migratory (...

  14. Antimicrobial, heavy metal resistance and plasmid profile of ...

    African Journals Online (AJOL)

    The antimicrobial, heavy metal resistance patterns and plasmid profiles of Coliforms (Enterobacteriacea) isolated from nosocomial infections and healthy human faeces were compared. Fifteen of the 25 isolates from nosocomial infections were identified as Escherichia coli, and remaining as Kelebsiella pneumoniae.

  15. The fight against Antimicrobial Resistance: Important recent publications

    DEFF Research Database (Denmark)

    Minssen, Timo

    2014-01-01

    One of my previous blogs discussed the growing threat of antimicrobial resistance (AMR). I concluded that antimicrobial resistance is a growing and complex threat involving multifaceted legal, socio-economic and scientific aspects. This requires sustained and coordinated action on both global...... to be tackled on a global level. That something is indeed being done to tackle these problems on an international level is documented by the Progress report of the Transatlantic Taskforce on Antimicrobial Resistance (TATFAR), which was published in May 2014. This report summarizes the progress and the outcomes...... with regard to 17 recommendations that were identified in an earlier TATFAR report to strengthen EU and US communication and cooperation in the area of AMR. These recommendations fall into three key areas: (1) appropriate use of antimicrobial drugs in medicine; (2) prevention of drug resistant infections...

  16. Antimicrobial resistance in clinical Escherichia coli isolated from companion animals in Australia.

    Science.gov (United States)

    Saputra, Sugiyono; Jordan, David; Mitchell, Tahlia; Wong, Hui San; Abraham, Rebecca J; Kidsley, Amanda; Turnidge, John; Trott, Darren J; Abraham, Sam

    2017-11-01

    Multidrug-resistant (MDR) Escherichia coli have become a major public health concern to both humans and animal health. While the frequency of antimicrobial resistance (AMR) in clinical E. coli is monitored regularly in human medicine, current frequency of AMR in companion animals remains unknown in Australia. In this study we conducted antimicrobial susceptibility testing (AST) and where possible, determined potential risk factors for MDR infection among 883 clinical Escherichia coli isolated from dogs (n=514), cats (n=341) and horses (n=28). AST was undertaken for 15 antimicrobial agents according to the Clinical Laboratory Standards Institute (CLSI) guidelines and interpreted using epidemiological cut-off values (ECOFFs) as well as CLSI veterinary and human clinical breakpoints. The AST revealed complete absence of resistance to carbapenems while resistance to amikacin was observed at a low level in isolates from dogs (1.6%) and cats (1.5%) compared to horses (10.7%). Among dog isolates, resistance to fluoroquinolones ranged from 9.1%-9.3% whereas among cat isolates, it ranged from 3.2%-5%. Among dog isolates, the proportion showing a 3rd generation cephalosporin (3GC) non-wild type phenotype was significantly higher (Presistance was 18.1%, 11.7% and 42.9% in dog, cat and horse isolates, respectively. Risk factor analysis revealed that MDR E. coli isolated from UTI were positively associated with chronicity of infection and previous antimicrobial treatment. Dogs and cats with chronic UTI that had been previously treated with antimicrobials were eight times and six times more likely to be infected with MDR E. coli compared to dogs and cats with non-chronic UTI, and no history of antimicrobial treatment, respectively. This study revealed that pre-existing disease condition and prior antimicrobial use were the major risks associated with UTI with MDR E. coli in companion animals. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

    Noor Uddin, Gazi Md; Larsen, Marianne Halberg; Christensen, Henrik; Aarestrup, Frank M; Phu, Tran Minh; Dalsgaard, Anders

    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 in aquaculture ponds. Concerns have been raised that the declared information on probiotic product labels are incorrect and information on bacterial composition are often missing. We therefore evaluated seven probiotics commonly used in Vietnamese shrimp culture for their bacterial species content, phenotypic 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. 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 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 that they contained macrolide (ermD), tetracycline (tetL), phenicol (fexA) and trimethoprim (dfrD, dfrG and dfrK) resistance genes, but not known structures associated with horizontal gene transfer. Probiotic bacterial strains used in Vietnamese shrimp culture seem to contribute with very limited types and numbers of resistance genes compared to the naturally occurring bacterial species in aquaculture environments. Approval procedures of probiotic products must be strengthened

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

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    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

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

    Science.gov (United States)

    Li, Lili; Heidemann Olsen, Rikke; Ye, Lei; Yan, He; Nie, Qing; Meng, Hecheng; Shi, Lei

    2016-04-01

    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 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 species, genes conferring antimicrobial resistance were observed with the following frequencies: blaTEM, 40.7%; blaCMY-2, 15.2%; blaCTX-M, 11.5%; sul2, 27.2%; sul1, 14.4%; tet(A), 5.4%; tet(L), 5.4%; tet(M), 5.0%; tet(E), 3.7%; tet(C), 3.3%; tet(S), 2.5%; and tet(K), 0.8%. Various antimicrobial resistance genes were found in new carriers: blaTEM in Lactococcus garvieae, Myroides odoratimimus, Aeromonas hydrophila, Staphylococcus sciuri, Raoultella terrigena, Macrococcus caseolyticus, Acinetobacter ursingii, Sphingobacterium sp., and Oceanobacillus sp.; blaCMY-2 in Lactococcus lactis, Klebsiella oxytoca, Serratia marcescens, Acinetobacter baumannii, and Myroides phaeus; tet(L) in M. caseolyticus; sul1 in Vibrio cincinnatiensis; sul2 in Acinetobacter bereziniae, Acinetobacter johnsonii, and V. cincinnatiensis; and the class 1 integron and gene cassette aadA2 in V. cincinnatiensis. Approximately 6.6% of isolates contained class 1 integrons, and one isolate harbored class 2 integrons. Plasmid associated intI1 and androgen receptor- encoding genes were transferred into Escherichia coli J53 and E. coli DH5α by conjugation and transformation experiments, respectively. Our study highlights the importance of aerobic bacteria from pork as reservoirs for antimicrobial resistance genes and mobile genetic elements that can readily be transferred intra- and interspecies.

  20. How to measure and monitor antimicrobial consumption and resistance.

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    Grau, Santiago; Bou, Germán; Fondevilla, Esther; Nicolás, Jordi; Rodríguez-Maresca, Manuel; Martínez-Martínez, Luis

    2013-09-01

    Collateral damage caused by antibiotic use includes resistance, which could be reduced if the global inappropriate use of antibiotics, especially in low-income countries, could be prevented. Surveillance of antimicrobial consumption can identify and target practice areas for quality improvement, both in the community and in healthcare institutions. The defined daily dose, the usual adult dose of an antimicrobial for treating one patient for one day, has been considered useful for measuring antimicrobial prescribing trends within a hospital. Various denominators from hospital activity including beds, admissions and discharges have been used to obtain some standard ratios for comparing antibiotic consumption between hospitals and countries. Laboratory information systems in Clinical Microbiology Services are the primary resource for preparing cumulative reports on susceptibility testing results. This information is useful for planning empirical treatment and for adopting infection control measures. Among the supranational initiatives on resistance surveillance, the EARS-Net provides information about trends on antimicrobial resistance in Europe. Resistance is the consequence of the selective pressure of antibiotics, although in some cases these agents also promote resistance by favouring the emergence of mutations that are subsequently selected. Multiple studies have shown a relationship between antimicrobial use and emergence or resistance. While in some cases a decrease in antibiotic use was associated with a reduction in resistance rates, in many other situations this has not been the case, due to co-resistance and/or the low biological cost of the resistance mechanisms involved. New antimicrobial agents are urgently needed, which coupled with infection control measures will help to control the current problem of antimicrobial resistance. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  1. 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.

  2. Prevalence and Genetic Basis of Antimicrobial Resistance in Non-aureusStaphylococci Isolated from Canadian Dairy Herds.

    Science.gov (United States)

    Nobrega, Diego B; Naushad, Sohail; Naqvi, S Ali; Condas, Larissa A Z; Saini, Vineet; Kastelic, John P; Luby, Christopher; De Buck, Jeroen; Barkema, Herman W

    2018-01-01

    Emergence and spread of antimicrobial resistance is a major concern for the dairy industry worldwide. Objectives were to determine: (1) phenotypic and genotypic prevalence of drug-specific resistance for 25 species of non-aureus staphylococci, and (2) associations between presence of resistance determinants and antimicrobial resistance. Broth micro-dilution was used to determine resistance profiles for 1,702 isolates from 89 dairy herds. Additionally, 405 isolates were sequenced to screen for resistance determinants. Antimicrobial resistance was clearly species-dependent. Resistance to quinupristin/dalfopristin was common in Staphylococcus gallinarum (prevalence of 98%), whereas S. cohnii and S. arlettae were frequently resistant to erythromycin (prevalence of 63 and 100%, respectively). Prevalence of resistance was 10% against β-lactams and tetracyclines. In contrast, resistance to antimicrobials critically important for human medicine, namely vancomycin, fluoroquinolones, linezolid and daptomycin, was uncommon (staphylococci from dairy cattle. These results will be important for evaluating effects of interventions in antimicrobial use in Canadian dairy herds.

  3. PointFinder: a novel web tool for WGS-based detection of antimicrobial resistance associated with chromosomal point mutations in bacterial pathogens

    DEFF Research Database (Denmark)

    Zankari, Ea; Allesøe, Rosa Lundbye; Joensen, Katrine Grimstrup

    2017-01-01

    Background Antibiotic resistance is a major health problem, as drugs that were once highly effective no longer cure bacterial infections. WGS has previously been shown to be an alternative method for detecting horizontally acquired antimicrobial resistance genes. However, suitable bioinformatics...... methods that can provide easily interpretable, accurate and fast results for antimicrobial resistance associated with chromosomal point mutations are still lacking. Methods Phenotypic antimicrobial susceptibility tests were performed on 150 isolates covering three different bacterial species: Salmonella...... were compared with phenotypic antimicrobial susceptibility testing results. Results A total of 685 different phenotypic tests associated with chromosomal resistance to quinolones, polymyxin, rifampicin, macrolides and tetracyclines resulted in 98.4% concordance. Eleven cases of disagreement between...

  4. Bacteria from Animals as a Pool of Antimicrobial Resistance Genes

    Science.gov (United States)

    Argudín, Maria Angeles; Deplano, Ariane; Meghraoui, Alaeddine; Dodémont, Magali; Heinrichs, Amelie; Denis, Olivier; Nonhoff, Claire; Roisin, Sandrine

    2017-01-01

    Antimicrobial agents are used in both veterinary and human medicine. The intensive use of antimicrobials in animals may promote the fixation of antimicrobial resistance genes in bacteria, which may be zoonotic or capable to transfer these genes to human-adapted pathogens or to human gut microbiota via direct contact, food or the environment. This review summarizes the current knowledge of the use of antimicrobial agents in animal health and explores the role of bacteria from animals as a pool of antimicrobial resistance genes for human bacteria. This review focused in relevant examples within the ESC(K)APE (Enterococcus faecium, Staphylococcus aureus, Clostridium difficile (Klebsiella pneumoniae), Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacteriaceae) group of bacterial pathogens that are the leading cause of nosocomial infections throughout the world. PMID:28587316

  5. Phenotypic and Genotypic Resistance of Salmonella Isolates from Healthy and Diseased Pigs in China During 2008-2015.

    Science.gov (United States)

    Jiu, Yueguang; Zhu, Shun; Khan, Sher Bahadar; Sun, Mengzhen; Zou, Geng; Meng, Xianrong; Wu, Bin; Zhou, Rui; Li, Shaowen

    2017-07-01

    The antimicrobial resistance of Salmonella strains is rapidly increasing worldwide, which poses significant threats to animal and public health. In this study, a total of 249 porcine Salmonella isolates collected in China during 2008-2015 were examined, including 155 clinical isolates from diseased pigs and 94 nonclinical isolates from healthy pigs. Based on the minimum inhibitory concentration of seven antimicrobial agents, 96.4% of the isolates were resistant to at least one of the tested antibiotics and 81.0% of them showed multidrug resistance. The highest antimicrobial resistance was observed for tetracycline (85.9%), and the lowest was found for cefotaxime (13.3%). The isolates from diseased pigs exhibited significantly higher levels of antimicrobial resistance than those from healthy pigs. Twenty-two isolates from healthy pigs were resistant to ciprofloxacin, which may inhibit the curative effectiveness of fluoroquinolones on bacterial food-borne poisoning and infections in humans caused by contaminated food. Moreover, cefotaxime resistance of the strains isolated from diseased pigs during 2013-2015 was significantly higher compared with the strains isolated during 2008-2010. Further study showed that the correlation between phenotypic and genotypic resistance varied among the isolates from different sources, and in many cases, the presence of resistance genes was not consistent with the resistance to the corresponding antimicrobials. These results are very significant for veterinary practice and public health.

  6. Antimicrobial resistance of Pseudomonas spp. isolated from wastewater and wastewater-impacted marine coastal zone.

    Science.gov (United States)

    Luczkiewicz, Aneta; Kotlarska, Ewa; Artichowicz, Wojciech; Tarasewicz, Katarzyna; Fudala-Ksiazek, Sylwia

    2015-12-01

    In this study, species distribution and antimicrobial susceptibility of cultivated Pseudomonas spp. were studied in influent (INF), effluent (EFF), and marine outfall (MOut) of wastewater treatment plant (WWTP). The susceptibility was tested against 8 antimicrobial classes, active against Pseudomonas spp.: aminoglycosides, carbapenems, broad-spectrum cephalosporins from the 3rd and 4th generation, extended-spectrum penicillins, as well as their combination with the β-lactamase inhibitors, monobactams, fluoroquinolones, and polymyxins. Among identified species, resistance to all antimicrobials but colistin was shown by Pseudomonas putida, the predominant species in all sampling points. In other species, resistance was observed mainly against ceftazidime, ticarcillin, ticarcillin-clavulanate, and aztreonam, although some isolates of Pseudomonas aeruginosa, Pseudomonas fluorescens, Pseudomonas pseudoalcaligenes, and Pseudomonas protegens showed multidrug-resistance (MDR) phenotype. Among P. putida, resistance to β-lactams and to fluoroquinolones as well as multidrug resistance become more prevalent after wastewater treatment, but the resistance rate decreased in marine water samples. Obtained data, however, suggests that Pseudomonas spp. are equipped or are able to acquire a wide range of antibiotic resistance mechanisms, and thus should be monitored as possible source of resistance genes.

  7. 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.

  8. 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 resistant bacteria and antimicrobial resistance genes exist in cattle, human, and swine waste streams, but a higher diversity of antimicrobial resistance genes are present

  9. Mechanisms of Antimicrobial Peptide Resistance in Gram-Negative Bacteria

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    Victor I. Band

    2014-12-01

    Full Text Available Cationic antimicrobial peptides (CAMPs are important innate immune defenses that inhibit colonization by pathogens and contribute to clearance of infections. Gram-negative bacterial pathogens are a major target, yet many of them have evolved mechanisms to resist these antimicrobials. These resistance mechanisms can be critical contributors to bacterial virulence and are often crucial for survival within the host. Here, we summarize methods used by Gram-negative bacteria to resist CAMPs. Understanding these mechanisms may lead to new therapeutic strategies against pathogens with extensive CAMP resistance.

  10. National disparities in the relationship between antimicrobial resistance and antimicrobial consumption in Europe: an observational study in 29 countries.

    Science.gov (United States)

    McDonnell, Lucy; Armstrong, David; Ashworth, Mark; Dregan, Alexandru; Malik, Umer; White, Patrick

    2017-11-01

    Antimicrobial resistance in invasive infections is driven mainly by human antimicrobial consumption. Limited cross-national comparative evidence exists about variation in antimicrobial consumption and effect on resistance. We examined the relationship between national community antimicrobial consumption rates (2013) and national hospital antimicrobial resistance rates (2014) across 29 countries in the European Economic Area (EEA). Consumption rates were obtained from the European Surveillance of Antimicrobial Consumption Network (ESAC-Net). Resistance data were obtained from the European Antimicrobial Resistance Surveillance Network (EARS-Net), based on 196480 invasive isolates in 2014. Data availability and consistency were good. Some countries did not report figures for each strain of resistant bacteria. National antimicrobial consumption rates (2013) varied from ≤ 13 DDD (Estonia, the Netherlands and Sweden) to ≥ 30 DDD (France, Greece and Romania) per 1000 inhabitants per day. National antimicrobial resistance rates (hospital isolates, 15 species) also varied from  37.2% (Bulgaria, Greece, Romania and Slovakia). National antimicrobial consumption rates (2013) showed strong to moderate correlation with national hospital antimicrobial resistance rates (2014) in 19 strains of bacteria (r = 0.84 to r = 0.39). Some countries defied the trend with high consumption and low resistance (France, Belgium and Luxembourg) or low consumption and high resistance (Bulgaria, Hungary and Latvia). We found associations between national community antimicrobial consumption and national hospital antimicrobial resistance across a wide range of bacteria. These associations were not uniform. Different mechanisms may drive resistance in hospital-based invasive infections. Future research on international variations in antimicrobial resistance should consider environmental factors, agricultural use, vaccination policies and prescribing quality. © The Author 2017

  11. Antimicrobial Resistance of Faecal Escherichia coli Isolates from Pig Farms with Different Durations of In-feed Antimicrobial Use.

    Science.gov (United States)

    Gibbons, J F; Boland, F; Egan, J; Fanning, S; Markey, B K; Leonard, F C

    2016-05-01

    Antimicrobial use and resistance in animal and food production are of concern to public health. The primary aims of this study were to determine the frequency of resistance to 12 antimicrobials in Escherichia coli isolates from 39 pig farms and to identify patterns of antimicrobial use on these farms. Further aims were to determine whether a categorization of farms based on the duration of in-feed antimicrobial use (long-term versus short-term) could predict the occurrence of resistance on these farms and to identify the usage of specific antimicrobial drugs associated with the occurrence of resistance. Escherichia coli were isolated from all production stages on these farms; susceptibility testing was carried out against a panel of antimicrobials. Antimicrobial prescribing data were collected, and farms were categorized as long term or short term based on these. Resistance frequencies and antimicrobial use were tabulated. Logistic regression models of resistance to each antimicrobial were constructed with stage of production, duration of antimicrobial use and the use of 5 antimicrobial classes included as explanatory variables in each model. The greatest frequencies of resistance were observed to tetracycline, trimethoprim/sulphamethoxazole and streptomycin with the highest levels of resistance observed in isolates from first-stage weaned pigs. Differences in the types of antimicrobial drugs used were noted between long-term and short-term use farms. Categorization of farms as long- or short-term use was sufficient to predict the likely occurrence of resistance to 3 antimicrobial classes and could provide an aid in the control of resistance in the food chain. Stage of production was a significant predictor variable in all models of resistance constructed and did not solely reflect antimicrobial use at each stage. Cross-selection and co-selection for resistance was evident in the models constructed, and the use of trimethoprim/sulphonamide drugs in particular was

  12. 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...... of antimicrobial's for mink. A total of 164 haemolytic staphylococci. 49 haemolytic streptococci. 39 Pseudomonas aeruginosa, 13 Pasteurella multocida. and 1093 Escherichia coli isolates front Danish mink were included in the Study. A high frequency of resistance among S. intermedius was found for tetracyclines (54.......7%). followed by penicillin (21.7%), lincosamides (20.4%), macrolides (19.1%), and spectinomycin (18.5%). Very low frequencies of resistance were recorded for other antimicrobials. The highest frequency among the E. coli isolates was recorded for ampicillin, streptomycin, sulphonamides, and tetracyclines...

  13. Statins: antimicrobial resistance breakers or makers?

    Directory of Open Access Journals (Sweden)

    Humphrey H.T. Ko

    2017-10-01

    Full Text Available Introduction The repurposing of non-antibiotic drugs as adjuvant antibiotics may help break antimicrobial resistance (AMR. Statins are commonly prescribed worldwide to lower cholesterol. They also possess qualities of AMR “breakers”, namely direct antibacterial activity, synergism with antibiotics, and ability to stimulate the host immune system. However, statins’ role as AMR breakers may be limited. Their current extensive use for cardiovascular protection might result in selective pressures for resistance, ironically causing statins to be AMR “makers” instead. This review examines statins’ potential as AMR breakers, probable AMR makers, and identifies knowledge gaps in a statin-bacteria-human-environment continuum. The most suitable statin for repurposing is identified, and a mechanism of antibacterial action is postulated based on structure-activity relationship analysis. Methods A literature search using keywords “statin” or “statins” combined with “minimum inhibitory concentration” (MIC was performed in six databases on 7th April 2017. After screening 793 abstracts, 16 relevant studies were identified. Unrelated studies on drug interactions; antifungal or antiviral properties of statins; and antibacterial properties of mevastatin, cerivastatin, antibiotics, or natural products were excluded. Studies involving only statins currently registered for human use were included. Results Against Gram-positive bacteria, simvastatin generally exerted the greatest antibacterial activity (lowest MIC compared to atorvastatin, rosuvastatin, and fluvastatin. Against Gram-negative bacteria, atorvastatin generally exhibited similar or slightly better activity compared to simvastatin, but both were more potent than rosuvastatin and fluvastatin. Discussion Statins may serve as AMR breakers by working synergistically with existing topical antibiotics, attenuating virulence factors, boosting human immunity, or aiding in wound healing. It

  14. FDA-CDC Antimicrobial Resistance Isolate Bank: a Publicly Available Resource To Support Research, Development, and Regulatory Requirements.

    Science.gov (United States)

    Lutgring, Joseph D; Machado, María-José; Benahmed, Faiza H; Conville, Patricia; Shawar, Ribhi M; Patel, Jean; Brown, Allison C

    2018-02-01

    The FDA-CDC Antimicrobial Resistance Isolate Bank was created in July 2015 as a publicly available resource to combat antimicrobial resistance. It is a curated repository of bacterial isolates with an assortment of clinically important resistance mechanisms that have been phenotypically and genotypically characterized. In the first 2 years of operation, the bank offered 14 panels comprising 496 unique isolates and had filled 486 orders from 394 institutions throughout the United States. New panels are being added. Copyright © 2018 American Society for Microbiology.

  15. 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 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 provision of information on sample size. Oral administration of antimicrobials increases the risk of AMR in E. coli from swine. There is however a lack of studies on the impact of dosage and longitudinal effects of treatment. The published studies have a number of issues concerning their scientific quality. More high quality research is needed to better address and quantifiy the effect of orally administered antimicrobials on AMR in swine. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Susceptibility to disinfectants in antimicrobial-resistant and -susceptible isolates of Escherichia coli, Enterococcus faecalis and Enterococcus faecium from poultry-ESBL/AmpC-phenotype of E. coli is not associated with resistance to a quaternary ammonium compound, DDAC.

    Science.gov (United States)

    Wieland, N; Boss, J; Lettmann, S; Fritz, B; Schwaiger, K; Bauer, J; Hölzel, C S

    2017-06-01

    The spread of bacteria that are simultaneously resistant to disinfectants and antimicrobials would constitute an unsettling scenario. In order to explore an association between antimicrobial resistance and reduced susceptibility to biocides/microbicides (disinfectants) in agriculture, we investigated Escherichia coli (n = 438) and enterococci (n = 120) isolated from six different flocks of the same poultry farm with known history of antimicrobial treatment. Susceptibility to disinfectants (formic acid and a quaternary ammonium compound (QAC), didecyldimethylammoniumchloride-DDAC) was assessed by macrodilution according to guidelines of the German Veterinary Society. Escherichia coli, Enterococcus faecalis and Enterococcus faecium were screened (i) for reduced biocide susceptibility and (ii) for an association of biocide susceptibility and antimicrobial resistance including the production of extended-spectrum beta-lactamases (ESBL) and the hyperproduction of AmpC-type beta-lactamases. DDAC inhibited ESBL/AmpC(hyper)-producing E. coli (n = 53) from poultry at similar or slightly lower inhibitory concentrations, compared with non-ESBL/AmpC strains (median MIC = 0·36 vs 1·44 mg l -1 ). In contrast, DDAC-MICs were positively correlated with several other antibiotic MICs (e.g. piperacillin and sulphamethoxazole + trimethoprim in E. coli, chloramphenicol in E. faecalis) and increased DDAC-MICs were statistically linked to high-level aminoglycoside resistance in enterococci (streptomycin high level). DDAC-MICs did not correlate with the presence of the integron marker qacEDelta1. This study provides indication that residual disinfectant might be able to select antimicrobial-resistant enterococci, but not ESBL-/AmpC (hyper)producing E. coli from poultry. While ESBL-/AmpC-E. coli were inhibited at disinfectant concentrations comparable to or lower than wildtype values, low concentrations of QACs might be able to select other antimicrobial-resistant E

  17. Macromolecular agents with antimicrobial potentialities: A drive to combat antimicrobial resistance.

    Science.gov (United States)

    Bilal, Muhammad; Rasheed, Tahir; Iqbal, Hafiz M N; Hu, Hongbo; Wang, Wei; Zhang, Xuehong

    2017-10-01

    In recent years, the antimicrobial resistance (AMR) or multidrug resistance (MDR) has become a serious health concern and major challenging issue, worldwide. After decades of negligence, the AMR has now captured global attention. The increasing number of antibiotic-resistant strains has threatened the achievements of science and medicine since it inactivates conventional antimicrobial therapeutics. Scientists are trying to respond to AMR/MDR threat by exploring innovative platforms and new therapeutic strategies to tackle infections from these resistant strains and bypass treatment limitations related to these pathologies. The present review focuses on the utilization of bio-inspired novel constructs and their potential applications as novel antimicrobial agents. The first part of the review describes plant-based biological macromolecules containing an immense variety of secondary metabolites, which could be potentially used as alternative strategies to combat antimicrobial resistance. The second part discusses the potential of metal-based macromolecules as effective antimicrobial platforms for preventing infections from resistant strains. The third part comprehensively elucidates how nanoparticles, in particular, metal-integrated nanoparticles can overcome this AMR or MDR issue. Towards the end, information is given with critical concluding remarks, gaps, and finally envisioned with future considerations. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Antimicrobial resistance and virulence characterization of Staphylococcus aureus and coagulase-negative staphylococci from imported beef meat.

    Science.gov (United States)

    Osman, Kamelia; Alvarez-Ordóñez, Avelino; Ruiz, Lorena; Badr, Jihan; ElHofy, Fatma; Al-Maary, Khalid S; Moussa, Ihab M I; Hessain, Ashgan M; Orabi, Ahmed; Saad, Alaa; Elhadidy, Mohamed

    2017-05-10

    The objectives of this study were to characterize the diversity and magnitude of antimicrobial resistance among Staphylococcus species recovered from imported beef meat sold in the Egyptian market and the potential mechanisms underlying the antimicrobial resistance phenotypes including harboring of resistance genes (mecA, cfr, gyrA, gyrB, and grlA) and biofilm formation. The resistance gene mecA was detected in 50% of methicillin-resistant non-Staphylococcus aureus isolates (4/8). Interestingly, our results showed that: (i) resistance genes mecA, gyrA, gyrB, grlA, and cfr were absent in Staphylococcus hominis and Staphylococcus hemolyticus isolates, although S. hominis was phenotypically resistant to methicillin (MR-non-S. aureus) while S. hemolyticus was resistant to vancomycin only; (ii) S. aureus isolates did not carry the mecA gene (100%) and were phenotypically characterized as methicillin- susceptible S. aureus (MSS); and (iii) the resistance gene mecA was present in one isolate (1/3) of Staphylococcus lugdunensis that was phenotypically characterized as methicillin-susceptible non-S. aureus (MSNSA). Our findings highlight the potential risk for consumers, in the absence of actionable risk management information systems, of imported foods and advice a strict implementation of international standards by different venues such as CODEX to avoid the increase in prevalence of coagulase positive and coagulase negative Staphylococcus isolates and their antibiotic resistance genes in imported beef meat at the Egyptian market.

  19. Mechanisms of antimicrobial resistance among hospital-associated pathogens.

    Science.gov (United States)

    Khan, Ayesha; Miller, William R; Arias, Cesar A

    2018-04-01

    The introduction of antibiotics revolutionized medicine in the 20th-century permitting the treatment of once incurable infections. Widespread use of antibiotics, however, has led to the development of resistant organisms, particularly in the healthcare setting. Today, the clinician is often faced with pathogens carrying a cadre of resistance determinants that severely limit therapeutic options. The genetic plasticity of microbes allows them to adapt to stressors via genetic mutations, acquisition or sharing of genetic material and modulation of genetic expression leading to resistance to virtually any antimicrobial used in clinical practice. Areas covered: This is a comprehensive review that outlines major mechanisms of resistance in the most common hospital-associated pathogens including bacteria and fungi. Expert commentary: Understanding the genetic and biochemical mechanisms of such antimicrobial adaptation is crucial to tackling the rapid spread of resistance, can expose unconventional therapeutic targets to combat multidrug resistant pathogens and lead to more accurate prediction of antimicrobial susceptibility using rapid molecular diagnostics. Clinicians making treatment decisions based on the molecular basis of resistance may design therapeutic strategies that include de-escalation of broad spectrum antimicrobial usage, more focused therapies or combination therapies. These strategies are likely to improve patient outcomes and decrease the risk of resistance in hospital settings.

  20. Towards a research agenda for water, sanitation and antimicrobial resistance.

    NARCIS (Netherlands)

    Wuijts, Susanne; van den Berg, Harold H J L; Miller, Jennifer; Abebe, Lydia; Sobsey, Mark; Andremont, Antoine; Medlicott, Kate O; van Passel, Mark W J; de Roda Husman, Ana Maria

    Clinically relevant antimicrobial resistant bacteria, genetic resistance elements, and antibiotic residues (so-called AMR) from human and animal waste are abundantly present in environmental samples. This presence could lead to human exposure to AMR. In 2015, the World Health Organization (WHO)

  1. Towards a research agenda for water, sanitation and antimicrobial resistance

    NARCIS (Netherlands)

    Wuijts, Susanne; van den Berg, Harold H J L; Miller, Jennifer; Abebe, Lydia; Sobsey, Mark; Andremont, Antoine; Medlicott, Kate O; van Passel, Mark W J; de Roda Husman, Ana Maria

    Clinically relevant antimicrobial resistant bacteria, genetic resistance elements, and antibiotic residues (so-called AMR) from human and animal waste are abundantly present in environmental samples. This presence could lead to human exposure to AMR. In 2015, the World Health Organization (WHO)

  2. Antimicrobial resistance of fecal isolates of salmonella and shigella ...

    African Journals Online (AJOL)

    Salmonellosis and Shigellosis coupled with increased levels of multidrug resistances are public health problems, especially in developing countries. This study was aimed at determining the prevalence of fecal Salmonella and Shigella spp and its antimicrobial resistance patterns. A retrospective study was conducted on ...

  3. 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. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Metalloproteins during development of Walker-256 carcinosarcoma resistant phenotype

    Directory of Open Access Journals (Sweden)

    V. F. Chekhun

    2015-04-01

    Full Text Available The study was focused on the detection of changes in serum and tumor metal-containing proteins in animals during development of doxorubicin-resistant phenotype in malignant cells after 12 courses of chemotherapy. We found that on every stage of resistance development there was a significant increase in content of ferritin and transferrin proteins (which take part in iron traffick and storage in Walker-256 carcinosarcoma tissue. We observed decreased serum ferritin levels at the beginning stage of the resistance development and significant elevation of this protein levels in the cases with fully developed resistance phenotype. Transferrin content showed changes opposite to that of ferritin. During the development of resistance phenotype the tumor tissue also exhibited increased ‘free iron’ concentration that putatively correlate with elevation of ROS generation and levels of MMP-2 and MMP-9 active forms. The tumor non-protein thiol content increases gradually as well. The serum of animals with early stages of resistance phenotype development showed high ceruloplasmin activity and its significant reduction after loss of tumor sensitivity to doxorubicin. Therefore, the development of resistance phenotype in Walker-256 carcinosarcoma is accompanied by both the deregulation of metal-containing proteins in serum and tumor tissue and by the changes in activity of antioxidant defense system. Thus, the results of this study allow us to determine the spectrum of metal-containing proteins that are involved in the development of resistant tumor phenotype and that may be targeted for methods for doxorubicin sensitivity correction therapy.

  5. Antimicrobial Use and Resistance in Australia (AURA) surveillance system: coordinating national data on antimicrobial use and resistance for Australia.

    Science.gov (United States)

    Turnidge, John D; Meleady, Kathy T

    2017-06-22

    Objective The aim of the present study was to describe the process of establishment and coordination of the national Antimicrobial Use and Resistance in Australia (AURA) surveillance system. Methods Existing surveillance programs conducted by health organisations at state or multi-jurisdictional levels were reviewed, and gaps and opportunities identified for the development of a national system. In view of the time frame available as part of the Australian Government Department of Health funding agreement, the strategy used by the Australian Commission on Safety and Quality in Health Care was to commence work with existing surveillance programs, expanding and enhancing them and developing new systems where gaps were identified. Using the specifications of the AURA national system, the data from each of these elements were then analysed and reported. The system provides coverage for the acute and community sectors for antimicrobial use and antimicrobial resistance. Results The AURA surveillance system integrates eight streams of surveillance activities, including passive and targeted surveillance of antimicrobial use and resistance from hospitals (public and private) and the community (general practitioners and aged care homes). A gap was identified in timely surveillance of critical antimicrobial resistances (CARs), which resulted in the development of the national CARAlert system. The first comprehensive analyses of data across the surveillance programs was published in June 2016, providing baseline data for future reports to build on. Conclusion The AURA surveillance system has established the framework and foundation systems for an integrated and comprehensive picture of both antimicrobial use and resistance in Australia over time. National coordination and support will improve data collection, standardisation and analysis, and will facilitate collaboration across the states and territories, the Australian Government and the private sector. AURA publications

  6. Narrow grass hedges reduce tylosin and associated antimicrobial resistance genes in agricultural runoff

    Science.gov (United States)

    Agricultural runoff from areas receiving livestock manure can potentially contaminate surface water with antimicrobials and antimicrobial resistance genes (ARGs). The objective of this study was to investigate the effectiveness of narrow grass hedges (NGHs) on reducing the transport of antimicrobial...

  7. Mycoplasma bovis: mechanisms of resistance and trends in antimicrobial susceptibility

    Directory of Open Access Journals (Sweden)

    Inna eLysnyansky

    2016-04-01

    Full Text Available 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.

  8. 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.

  9. Phenotypic methods for determination of methicillin resistance in Staphylococcus spp. from health care workers

    Directory of Open Access Journals (Sweden)

    Marcelle Aquino Rabelo

    2013-04-01

    Full Text Available INTRODUCTION: Staphylococcus spp. is an important healthcare-associated pathogen and the identification of methicillin-resistant strains in samples of colonization may provide data to assist in the antimicrobial therapy success. OBJECTIVES: To determine the occurrence of colonization by methicillin-resistant Staphylococcus spp. (MRS, through the detection of the mecA gene and to evaluate different phenotypic methods for the presumptive detection of methicillin resistance in samples of the anterior nasal cavity and hands of the health care personnel of a university hospital in the state of Pernambuco, Brazil. METHODS: We selected the 28 isolates of Staphylococcus spp., which showed an intermediate or resistant phenotypic profile for oxacillin, detected by the Kirby Bauer technique. The methods used were disk-diffusion tests for cefoxitin, minimal inhibitory concentration by E-test for oxacillin, screening for oxacillin resistance and mecA gene detection by polymerase chain reaction (PCR. RESULTS: About the phenotypic methods utilized, only the E-test of oxacillin did not show a statistically significant difference in relation to PCR for the mecA gene detection, considered the gold standard. CONCLUSION: The E-test of oxacillin was the best of the phenotypic methods utilized. It is necessary to correctly detect MRS in healthy individuals, because they can act as carriers and can therefore be a potential source of microorganisms involved in hospital infections.

  10. Occurrence of Diverse Antimicrobial Resistance Determinants in Genetically Unrelated Biocide Tolerant Klebsiella pneumoniae.

    Directory of Open Access Journals (Sweden)

    Amitabha Mondal

    Full Text Available Nosocomial infections due to Klebsiella pneumoniae is a significant problem in health care settings worldwide. In this study, we examined the antimicrobial susceptibility, genetic profiles and mechanisms of antibiotic resistance in K. pneumoniae isolates of Indian origin. To our knowledge this is the first report demonstrating the high prevalence of β-lactamases, aminoglycoside modifying enzymes, quinolone resistance genes besides demonstrating the involvement of active efflux in K. pneumoniae Indian isolates. This study has enabled us to correlate the phenotypic and genotypic characteristics in K. pneumoniae, providing an important base for continued monitoring and epidemiological studies of this emerging nosocomial pathogen in Indian hospitals.

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

    Directory of Open Access Journals (Sweden)

    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.

  12. The evolution of antimicrobial peptide resistance in Pseudomonas aeruginosa is shaped by strong epistatic interactions

    DEFF Research Database (Denmark)

    Jochumsen, Nicholas; Marvig, Rasmus Lykke; Pedersen, Søren Damkiær

    2016-01-01

    Colistin is an antimicrobial peptide that has become the only remaining alternative for the treatment of multidrug-resistant Gram-negative bacterial infections, but little is known of how clinical levels of colistin resistance evolve. We use in vitro experimental evolution and whole-genome sequen......Colistin is an antimicrobial peptide that has become the only remaining alternative for the treatment of multidrug-resistant Gram-negative bacterial infections, but little is known of how clinical levels of colistin resistance evolve. We use in vitro experimental evolution and whole......-genome sequencing of colistin-resistant Pseudomonas aeruginosa isolates from cystic fibrosis patients to reconstruct the molecular evolutionary pathways open for high-level colistin resistance. We show that the evolution of resistance is a complex, multistep process that requires mutation in at least five...... independent loci that synergistically create the phenotype. Strong intergenic epistasis limits the number of possible evolutionary pathways to resistance. Mutations in transcriptional regulators are essential for resistance evolution and function as nodes that potentiate further evolution towards higher...

  13. Short communication: Antimicrobial resistance and virulence characterization of methicillin-resistant staphylococci isolates from bovine mastitis cases in Portugal.

    Science.gov (United States)

    Seixas, R; Santos, J P; Bexiga, R; Vilela, C L; Oliveira, M

    2014-01-01

    Methicillin-resistant staphylococci (MRS) have already been reported as mastitis agents. Such bacterial species are a public health concern, and the characterization of their antimicrobial resistance and virulence profile is important to better control their dissemination. The present work evaluated the distribution of methicillin-resistance among 204 staphylococci from clinical (n=50) and subclinical (n=154) bovine mastitis. The presence ofthe mecA gene was determined by PCR. Phenotypic expression of coagulase, DNase, lipase, gelatinase, hemolytic enzymes, and biofilm production was evaluated. The presence of biofilm-related genes, icaA, icaD, and bap, was also determined. Antimicrobial resistance patterns for aminoglycosides, lincosamides, macrolides, fluoroquinolones, sulphonamides, tetracyclines, and fusidic acid were determined. Nineteen (9.3%) isolates were identified as MRS, and the presence of mecA in these isolates was confirmed by PCR. Virulence factors evaluation revealed that gelatinase was the most frequently detected (94.7%), followed by hemolysins (73.7%) and lipase (68.4%); 84.2% of the MRS isolates produced biofilm and icaA and icaD were detected in almost half of the MRS isolates (52.6%), but all were bap-negative. Resistance against other antimicrobial agents ranged from 0 (fusidic acid, ciprofloxacin, norfloxacin, enrofloxacin) to 100% (nalidixic acid). Resistance to nalidixic acid and nalidixic acid-tetracycline were the most common antimicrobial resistance profiles (31.6%). This study confirms that despite the low prevalence of MRS, isolates frequently express other virulence traits, especially biofilm, that may represent a serious challenge to clinicians. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  14. Genotypic and Phenotypic Markers of Livestock-Associated Methicillin-Resistant Staphylococcus aureus CC9 in Humans

    OpenAIRE

    Ye, Xiaohua; Wang, Xiaolin; Fan, Yanping; Peng, Yang; Li, Ling; Li, Shunming; Huang, Jingya; Yao, Zhenjiang; Chen, Sidong

    2016-01-01

    Use of antimicrobials in industrial food animal production is associated with the presence of multidrug-resistant Staphylococcus aureus among animals and humans. The livestock-associated (LA) methicillin-resistant S. aureus (MRSA) clonal complex 9 (CC9) is associated with animals and related workers in Asia. This study aimed to explore the genotypic and phenotypic markers of LA-MRSA CC9 in humans. We conducted a cross-sectional study of livestock workers and controls in Guangdong, China. The ...

  15. National Antimicrobial Resistance Monitoring System: Two Decades of Advancing Public Health Through Integrated Surveillance of Antimicrobial Resistance.

    Science.gov (United States)

    Karp, Beth E; Tate, Heather; Plumblee, Jodie R; Dessai, Uday; Whichard, Jean M; Thacker, Eileen L; Hale, Kis Robertson; Wilson, Wanda; Friedman, Cindy R; Griffin, Patricia M; McDermott, Patrick F

    2017-10-01

    Drug-resistant bacterial infections pose a serious and growing public health threat globally. In this review, we describe the role of the National Antimicrobial Resistance Monitoring System (NARMS) in providing data that help address the resistance problem and show how such a program can have broad positive impacts on public health. NARMS was formed two decades ago to help assess the consequences to human health arising from the use of antimicrobial drugs in food animal production in the United States. A collaboration among the Centers for Disease Control and Prevention, the U.S. Food and Drug Administration, the United States Department of Agriculture, and state and local health departments, NARMS uses an integrated "One Health" approach to monitor antimicrobial resistance in enteric bacteria from humans, retail meat, and food animals. NARMS has adapted to changing needs and threats by expanding surveillance catchment areas, examining new isolate sources, adding bacteria, adjusting sampling schemes, and modifying antimicrobial agents tested. NARMS data are not only essential for ensuring that antimicrobial drugs approved for food animals are used in ways that are safe for human health but they also help address broader food safety priorities. NARMS surveillance, applied research studies, and outbreak isolate testing provide data on the emergence of drug-resistant enteric bacteria; genetic mechanisms underlying resistance; movement of bacterial populations among humans, food, and food animals; and sources and outcomes of resistant and susceptible infections. These data can be used to guide and evaluate the impact of science-based policies, regulatory actions, antimicrobial stewardship initiatives, and other public health efforts aimed at preserving drug effectiveness, improving patient outcomes, and preventing infections. Many improvements have been made to NARMS over time and the program will continue to adapt to address emerging resistance threats, changes in

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

    International Nuclear Information System (INIS)

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

    2013-01-01

    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. - 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

  17. Insights on antimicrobial resistance, biofilms and the use of phytochemicals as new antimicrobial agents.

    Science.gov (United States)

    Borges, Anabela; Saavedra, Maria J; Simões, Manuel

    2015-01-01

    Antimicrobial resistance is one of the most serious public health problems. This is of particular concern when bacteria become resistant to various antimicrobial agents simultaneously and when they form biofilms. Consequently, therapeutic options for the treatment of infections have become limited, leading frequently to recurrent infections, treatment failure and increase of morbidity and mortality. Both, persistence and spread of antibiotic resistance, in combination with decreased effectiveness and increased toxicity of current antibiotics have emphasized the urgent need to search alternative sources of antimicrobial substances. Plants are recognized as a source of unexplored chemical structures with high therapeutic potential, including antimicrobial activity against clinically important microorganisms. Additionally, phytochemicals (plant secondary metabolites) present several advantages over synthetic molecules, including green status and different mechanisms of action from antibiotics which could help to overcome the resistance problem. In this study, an overview of the main classes of phytochemicals with antimicrobial properties and their mode of action is presented. A revision about the application of phytochemicals for biofilm prevention and control is also done. Moreover, the use of phytochemicals as scaffolds of new functional molecules to expand the antibiotics pipeline is reviewed.

  18. Opinions of clinical veterinarians at a US veterinary teaching hospital regarding antimicrobial use and antimicrobial-resistant infections.

    Science.gov (United States)

    Jacob, Megan E; Hoppin, Jane A; Steers, Nicola; Davis, Jennifer L; Davidson, Gigi; Hansen, Bernie; Lunn, Katharine F; Murphy, K Marcia; Papich, Mark G

    2015-10-15

    To determine opinions of faculty members with clinical appointments, clinical veterinarians, residents, and interns at a US veterinary teaching hospital regarding antimicrobial use and antimicrobial-resistant infections. Cross-sectional survey. 71 veterinarians. An online questionnaire was sent to all veterinarians with clinical service responsibilities at the North Carolina State University veterinary teaching hospital (n = 167). The survey included 23 questions regarding demographic information, educational experiences, current prescribing practices, and personal opinions related to antimicrobial selection, antimicrobial use, restrictions on antimicrobial use, and antimicrobial resistance. Of the 167 veterinarians eligible to participate, 71 (43%) responded. When respondents were asked to rate their level of concern (very concerned = 1; not concerned = 5) about antimicrobial-resistant infections, most (41/70 [59%]) assigned a score of 1, with mean score for all respondents being 1.5. Most survey participants rated their immediate colleagues (mean score, 1.9) as more concerned than other veterinary medical professionals (mean score, 2.3) and their clients (mean score, 3.4). Fifty-nine of 67 (88%) respondents felt that antimicrobials were overprescribed at the hospital, and 32 of 69 (46%) respondents felt uncomfortable prescribing at least one class of antimicrobials (eg, carbapenems or glycopeptides) because of public health concerns. Findings indicated that veterinarians at this teaching hospital were concerned about antimicrobial resistance, thought antimicrobials were overprescribed, and supported restricting use of certain antimicrobial classes in companion animals. Findings may be useful in educating future veterinarians and altering prescribing habits and antimicrobial distribution systems in veterinary hospitals.

  19. Epidemiology of Antimicrobial Resistance among Escherichia coli Strains in Trans-Nzoia County, Kenya

    Directory of Open Access Journals (Sweden)

    Collins Kibenei Kipkorir, Philip Bett, Patrick O. Onyango

    2016-09-01

    Full Text Available Objective: This study aimed to determine prevalence, antimicrobial susceptibility profile and the genetic basis to antimicrobial resistance, targeting blaTEM gene expression of diarrheagenic Escherichia coli among patients suffering from gastroenteritis in Kitale County Referral Hospital. Methods: A cross-sectional study design was adopted. A total of 103 fecal specimens were collected from participants ranging in age from two weeks to 82 years. E. coli was isolated and identified based on phenotypic and biochemical properties. Antimicrobial susceptibility was determined by Kirby-Bauer disk diffusion method. Polymerase chain reaction was used to detect the presence of blaTEM gene. Results: The prevalence of E. coli was 90.2% and age of the patient explained 53% of variation in prevalence. Isolates of diarrheagenic E. coli showed varied degree of susceptibility with sulfamethoxazole at 97%, co-trimoxazole 96%, ampicillin 84%, chloramphenicol 27%, tetracycline 16%, kanamycin 10% and streptomycin 9%. However, E. coli was highly sensitive to gentamicin at 96.8%. Approximately 42.2% of E. coli isolates were multidrug resistant to sulfamethoxazole, co-trimoxazole, ampicillin, chloramphenicol, tetracycline, kanamycin and streptomycin. All isolates that were resistant to ampicillin harbored blaTEM gene suggesting genetic mediation. Conclusion: The observed pattern of resistance to antibiotics points to the need to regulate their use and arrest buildup of resistant genes within the population. J Microbiol Infect Dis 2016;6(3: 107-112

  20. Markov Networks of Collateral Resistance: National Antimicrobial Resistance Monitoring System Surveillance Results from Escherichia coli Isolates, 2004-2012.

    Directory of Open Access Journals (Sweden)

    William J Love

    2016-11-01

    Full Text Available Surveillance of antimicrobial resistance (AMR is an important component of public health. Antimicrobial drug use generates selective pressure that may lead to resistance against to the administered drug, and may also select for collateral resistances to other drugs. Analysis of AMR surveillance data has focused on resistance to individual drugs but joint distributions of resistance in bacterial populations are infrequently analyzed and reported. New methods are needed to characterize and communicate joint resistance distributions. Markov networks are a class of graphical models that define connections, or edges, between pairs of variables with non-zero partial correlations and are used here to describe AMR resistance relationships. The graphical least absolute shrinkage and selection operator is used to estimate sparse Markov networks from AMR surveillance data. The method is demonstrated using a subset of Escherichia coli isolates collected by the National Antimicrobial Resistance Monitoring System between 2004 and 2012 which included AMR results for 16 drugs from 14418 isolates. Of the 119 possible unique edges, 33 unique edges were identified at least once during the study period and graphical density ranged from 16.2% to 24.8%. Two frequent dense subgraphs were noted, one containing the five β-lactam drugs and the other containing both sulfonamides, three aminoglycosides, and tetracycline. Density did not appear to change over time (p = 0.71. Unweighted modularity did not appear to change over time (p = 0.18, but a significant decreasing trend was noted in the modularity of the weighted networks (p < 0.005 indicating relationships between drugs of different classes tended to increase in strength and frequency over time compared to relationships between drugs of the same class. The current method provides a novel method to study the joint resistance distribution, but additional work is required to unite the underlying biological and genetic

  1. Antimicrobial Activity of Actinomycetes Against Multidrug Resistant ...

    African Journals Online (AJOL)

    Results: Among these isolates, 51 (38 %) showed antimicrobial activity against one or more test organisms and six exhibited promising broad-spectrum activity against all the tested organisms. The observed cultural, morphological, physiological and biochemical characteristics confirmed that these isolates are species of ...

  2. Current resistance issues in antimicrobial therapy | Senekal ...

    African Journals Online (AJOL)

    The human gut contains 1013 - 1014 bacteria that are exposed to selection pressure whenever antibiotics are administered.1 The same selection pressure applies to respiratory flora, which is one of the reasons why antimicrobial therapy prescribed for the treatment of respiratory tract infection should aim to eradicate ...

  3. Prevalence and antimicrobial resistance in Campylobacter from ...

    African Journals Online (AJOL)

    Poultry are recognized as a main reservoir of Campylobacter spp. However, longitudinal studies investigating the persistence of Campylobacter on broilers and retail chciekn meat in Tanzania are rare. The aim of the current work was to evaluate the prevalence and antimicrobial susceptibility of Campylobacter spp. isolated ...

  4. Antimicrobial resistance and plasmid profiles of Aeromonas ...

    African Journals Online (AJOL)

    The purpose of this study was to investigate the presence of Aeromonas hydrophila at commonly used water collection points on the River Njoro and to determine the in-vitro antimicrobial susceptibility and plasmid profiles of isolates. In total, 126 samples were collected and 36.5% of them were positive for A. hydrophila.

  5. Characterization and Antimicrobial Resistance of Salmonella Typhimurium Isolates from Clinically Diseased Pigs in Korea.

    Science.gov (United States)

    Oh, Sang-Ik; Kim, Jong Wan; Chae, Myeongju; Jung, Ji-A; So, Byungjae; Kim, Bumseok; Kim, Ha-Young

    2016-11-01

    This study investigated the prevalence of Salmonella enterica serovar and antimicrobial resistance in Salmonella Typhimurium isolates from clinically diseased pigs collected from 2008 to 2014 in Korea. Isolates were also characterized according to the presence of antimicrobial resistance genes and pulsed-field gel electrophoresis patterns. Among 94 Salmonella isolates, 81 (86.2%) were identified as being of the Salmonella Typhimurium serotype, followed by Salmonella Derby (6 of 94, 6.4%), Salmonella 4,[5],12:i:- (4 of 94, 4.3%), Salmonella Enteritidis (2 of 94, 2.1%), and Salmonella Brandenburg (1 of 94, 1.1%). The majority of Salmonella Typhimurium isolates were resistant to tetracycline (92.6%), followed by streptomycin (88.9%) and ampicillin (80.2%). Overall, 96.3% of Salmonella Typhimurium isolates showed multidrug-resistant phenotypes and commonly harbored the resistance genes bla TEM (64.9%), flo (32.8%), aadA (55.3%), strA (58.5%), strB (58.5%), sulII (53.2%), and tetA (61.7%). The pulsed-field gel electrophoresis analysis of 45 Salmonella Typhimurium isolates from individual farms revealed 27 distinct patterns that formed one major and two minor clusters in the dendrogram analysis, suggesting that most of the isolates (91.1%) from diseased pigs were genetically related. These findings can assist veterinarians in the selection of appropriate antimicrobial agents to combat Salmonella Typhimurium infections in pigs. Furthermore, they highlight the importance of continuous surveillance of antimicrobial resistance and genetic status in Salmonella Typhimurium for the detection of emerging resistance trends.

  6. Effect of preweaned dairy calf housing system on antimicrobial resistance in commensal Escherichia coli.

    Science.gov (United States)

    Pereira, R V; Siler, J D; Ng, J C; Davis, M A; Warnick, L D

    2014-12-01

    Group housing of preweaned dairy calves is a growing practice in the United States. The objective of this practice is to increase the average daily gain of calves in a healthy and humane environment while reducing labor requirements. However, feeding protocols, commingling of calves, and occurrence of disease in different calf-housing systems may affect the prevalence of antimicrobial drug-resistant bacteria. This study evaluated the effect of a group pen-housing system and individual pen-housing system on antimicrobial resistance trends in fecal Escherichia coli of preweaned dairy calves and on the prevalence of environmental Salmonella. Twelve farms from central New York participated in the study: 6 farms using an individual pen-housing system (IP), and 6 farms using a group pen-housing system (GP). A maximum of 3 fecal E. coli isolates per calf was tested for susceptibility to 12 antimicrobial drugs using a Kirby-Bauer disk diffusion assay. Calves in GP had a significantly higher proportion of E. coli resistant to ciprofloxacin and nalidixic acid, whereas calves in IP had a significantly higher proportion of E. coli resistant to ampicillin, ceftiofur, gentamycin, streptomycin, and tetracycline. Calf-housing system had an effect on resistance to individual antimicrobial drugs in E. coli, but no clear-cut advantage to either system was noted with regard to overall resistance frequency. No outstanding difference in the richness and diversity of resistant phenotypes was observed between the 2 calf-housing systems. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  7. Effects of chlortetracycline and copper supplementation on antimicrobial resistance of fecal Escherichia coli from weaned pigs.

    Science.gov (United States)

    Agga, G E; Scott, H M; Amachawadi, R G; Nagaraja, T G; Vinasco, J; Bai, J; Norby, B; Renter, D G; Dritz, S S; Nelssen, J L; Tokach, M D

    2014-06-01

    Feed-grade chlortetracycline (CTC) and copper are both widely utilized in U.S. pig production. Cluster randomized experiment was conducted to evaluate the effects of CTC and copper supplementation in weaned pigs on antimicrobial resistance (AMR) among fecal Escherichia coli. Four treatment groups: control, copper, CTC, or copper plus CTC were randomly allocated to 32 pens with five pigs per pen. Fecal samples were collected weekly from three pigs per pen for six weeks. Two E. coli isolates per fecal sample were tested for phenotypic and genotypic resistance against antibiotics and copper. Data were analyzed with multilevel mixed effects logistic regression, multivariate probit analysis and discrete time survival analysis. CTC-supplementation was significantly (99% [95% CI=98-100%]) associated with increased tetracycline resistance compared to the control group (95% [95% CI=94-97%]). Copper supplementation was associated with decreased resistance to most of the antibiotics tested, including cephalosporins, over the treatment period. Overall, 91% of the E. coli isolates were multidrug resistant (MDR) (resistant to ≥3 antimicrobial classes). tetA and blaCMY-2 genes were positively associated (Ppigs exhibited high levels of antibiotic resistance, with diverse multi-resistant phenotypic profiles. The roles of copper supplementation in pig production, and pco-mediated copper resistance among E. coli in particular, need to be further explored since a strong negative association of pco with both tetA and blaCMY-2 points to opportunities for selecting a more innocuous resistance profile. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Antimicrobial resistance profiles among Escherichia coli strains isolated from commercial and cooked foods.

    Science.gov (United States)

    Ryu, Seung-Hee; Lee, Jip-Ho; Park, Sang-Hoon; Song, Mi-Ok; Park, Sun-Hee; Jung, Hyo-Won; Park, Geon-Yong; Choi, Sung-Min; Kim, Moo-Sang; Chae, Young-Zoo; Park, Seog-Gee; Lee, Young-Ki

    2012-10-15

    A total of 4330 food samples of which microbiological standard for Escherichia coli is negative in Korea were determined for the frequency of E. coli. Ninety six samples (2.2%) were positive for E. coli. Detection rate of E. coli varied significantly by food type and ranged from 0.3% to 10.9%. Seasoned raw meat (yukhoe) and cold bean-soup had the highest prevalence for E. coli (10.9%) followed by gimbap (5.2%), meat broth for cold noodle (2.9%) and sprout (2.1%). E. coli isolates (n=96) were investigated for their phenotypic and genotypic antimicrobial resistance patterns. Seventeen E. coli isolates (17.7%) were resistant to one or more antimicrobial agents tested. High rates of resistance to the following drugs were observed: tetracycline (15.6%), streptomycin (12.5%), ampicillin (10.4%), nalidixic acid (9.4%) and ticarcillin (9.4%). All ampicillin resistant isolates were screened for extended-spectrum β-lactamase (ESBL) production by the combination disk test. None of the E. coli isolates produced ESBLs. Seventeen out of 96 E. coli isolates which were resistant to at least one antibiotic were investigated by PCR for the presence of 3 classes of antimicrobial resistance genes (tetracycline, aminoglycosides and beta-lactams). The tetracycline resistance genes tetA and tetB were found in 7 and 5 isolates, respectively. The aminoglycoside resistance genes, strA/B, aphA1, aadA and aac(3)-IV were found in 9, 5, 2 and 2 isolates, respectively. The beta-lactam resistance gene, bla(TEM) was found in 7 isolates. Results of this study show that 13 E. coli isolates were multidrug resistant (to three or more antibiotics) and 12 isolates carried at least one antimicrobial resistance gene. These isolates can act as the reservoir for antimicrobial resistance genes and facilitate the dissemination of these genes to other pathogenic and commensal bacteria. Adequate intervention to reduce microbial contamination of these foods is strongly recommended. Copyright © 2012 Elsevier B

  9. Studying the Phenotypic and Genotypic Expression of Antibiotic Resistance in Campylobacter jejuni under Stress Conditions.

    Science.gov (United States)

    Efimochkina, N R; Stetsenko, V V; Bykova, I V; Markova, Yu M; Polyanina, A S; Aleshkina, A I; Sheveleva, S A

    2018-03-01

    Specific features for the development of resistance in Campylobacter jejuni strains were studied after treatment with antibiotics of 6 pharmacological groups. Populations of 18 native strains of C. jejuni (isolated from raw poultry products) and their subcultures (obtained after 2-3-fold stress exposures to antimicrobial agents in subinhibitory doses) were examined to evaluate the expression of phenotypic antibiotic resistance. Genotypic properties of strains were studied by the PCR with primers that detect the presence of genes for resistance to aminoglycosides (aphA-1, aphA-3, and aphA-7), tetracyclines (tetO), and quinolones (GZgyrA). The majority of test strains of C. jejuni exhibited a high resistance to nalidixic acid, ciprofloxacin, and tetracycline, which reached the maximum value after numerous passages. The expression of antibiotic resistance was greatest in the presence of nalidixic acid and tetracycline. Ciprofloxacin resistance of 33% strains, which were initially resistant to this antibiotic, was increased after 2-3-fold treatment. We revealed a high degree of correspondence between phenotypic and genotypic profiles of antibiotic resistance in food isolates of Campylobacter. One, two, or more genes of aphA were identified in 85% strains phenotypically resistant to aminoglycosides. The tetO gene was found nearly in all strains resistant to tetracycline. Studying the biofilm matrix in C. jejuni after culturing with antibiotics in subinhibitory doses showed that quinolones (particularly nalidixic acid) and tetracyclines potentiate the formation of biofilms and increase the tolerance of Campylobacter to stress exposures. The intensity of biofilm growth was shown to depend little on the effect of macrolides and aminoglycosides. Therefore, the presence of these agents in residual concentrations is associated with a lower risk for the development of antibiotic resistance in C. jejuni populations.

  10. Antimicrobial Usage and Antimicrobial Resistance in Animal Production in Southeast Asia: A Review

    Directory of Open Access Journals (Sweden)

    Nguyen T. Nhung

    2016-11-01

    Full Text Available Southeast Asia is an area of great economic dynamism. In recent years, it has experienced a rapid rise in the levels of animal product production and consumption. The region is considered to be a hotspot for infectious diseases and antimicrobial resistance (AMR. We reviewed English-language peer-reviewed publications related to antimicrobial usage (AMU and AMR in animal production, as well as antimicrobial residues in meat and fish from 2000 to 2016, in the region. There is a paucity of data from most countries and for most bacterial pathogens. Most of the published work relates to non-typhoidal Salmonella (NTS, Escherichia coli (E. coli, and Campylobacter spp. (mainly from Vietnam and Thailand, Enterococcus spp. (Malaysia, and methicillin-resistant Staphylococcus aureus (MRSA (Thailand. However, most studies used the disk diffusion method for antimicrobial susceptibility testing; breakpoints were interpreted using Clinical Standard Laboratory Institute (CSLI guidelines. Statistical models integrating data from publications on AMR in NTS and E. coli studies show a higher overall prevalence of AMR in pig isolates, and an increase in levels of AMR over the years. AMU studies (mostly from Vietnam indicate very high usage levels of most types of antimicrobials, including beta-lactams, aminoglycosides, macrolides, and quinolones. This review summarizes information about genetic determinants of resistance, most of which are transferrable (mostly plasmids and integrons. The data in this review provide a benchmark to help focus research and policies on AMU and AMR in the region.

  11. Neisseria gonorrhoeae: testing, typing and treatment in an era of increased antimicrobial resistance

    NARCIS (Netherlands)

    Wind, C.M.

    2017-01-01

    This thesis discusses the management of Neisseria gonorrhoeae infections while under threat of emerging antimicrobial resistance. It focuses on improved diagnostics, and antimicrobial resistance to current and future therapies. We describe a new method of targeted deferred culture, using nucleic

  12. Molecular clonality and antimicrobial resistance in Salmonella enterica serovars Enteritidis and Infantis from broilers in three Northern regions of Iran

    DEFF Research Database (Denmark)

    Rahmani, Maral; Peighambari, Seyed Mostafa; Svendsen, Christina Aaby

    2013-01-01

    ) were resistant to tetracycline, spectinomycin, streptomycin, and sulfamethoxazole and harbored the associated resistance genes; tetA, dfrA14, aadA1, and sulI together with class 1 integrons. The isolates revealed highly similar PFGE patterns indicating clonal relatedness across different geographical......ABSTRACT: BACKGROUND: Multidrug-resistant Salmonella strains are frequently encountered problems worldwide with considerable increased occurrences in recent years. The aim of this study was to investigate the occurrence and frequency of antimicrobial resistance and associated resistance genes......, and characterized for antimicrobial resistance genes associated to the phenotype. Pulsed-field gel electrophoresis (PFGE) was applied for comparison of genetic relatedness.Two serovars were detected among the isolates; Salmonella enterica serovar Infantis (75%) and S. Enteritidis (25%). Thirty-four (94...

  13. Methods to Study Antimicrobial Resistance in Campylobacter jejuni.

    Science.gov (United States)

    Sahin, Orhan; Shen, Zhangqi; Zhang, Qijing

    2017-01-01

    Campylobacter jejuni is a leading bacterial cause of foodborne gastroenteritis worldwide and is increasingly resistant to clinically important antibiotics. Detection of antibiotic resistance in C. jejuni can be performed with both phenotypic and genotypic methods. In this chapter, we describe the most commonly used molecular biology methods for detection of resistance to clinically important antibiotics. These methods can be employed in both clinical and research settings to facilitate clinical therapy and to monitor the emergence and dissemination of antibiotic-resistant C. jejuni.

  14. Antibiotic and Antimicrobial Resistance: Threat Report 2013

    Science.gov (United States)

    ... Role What CDC is Doing: AR Solutions Initiative Investing in States: Map Antibiotic Resistance Lab Network Antibiotic ... CDC and Partners Tackle Drug-Resistant TB in India Newly Reported Gene, mcr -1, Threatens Last-Resort ...

  15. Multidrug Resistant Acinetobacter Infection and Their Antimicrobial ...

    African Journals Online (AJOL)

    Conclusion: The high rate of antibiotic resistance shown by Acintobacter isolates in this study demonstrates the need for antibiotic stewardship protocols to be set up in health facilities to prevent outbreaks of multi-resistant bacterial infections. Key words: Acinotebacter infection, Multidrug resistant, Intensive care unit.

  16. Antimicrobial Resistance: A Global Public Health Threat

    African Journals Online (AJOL)

    The 60 years of the antibiotic era has been marked by cycles of discovery of new antibiotics and the subsequent emergence of drug resistance. Imprudent use of antibiotics has lead to the development of resistance which has reached a grave situation. The factors which increase bacterial resistance to antibiotics are the ...

  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. Salmonella Heidelberg: Genetic profile of its antimicrobial resistance related to extended spectrum β-lactamases (ESBLs).

    Science.gov (United States)

    Giuriatti, Jéssica; Stefani, Lenita Moura; Brisola, Maiara Cristina; Crecencio, Regiane Boaretto; Bitner, Dinael Simão; Faria, Gláucia Amorim

    2017-08-01

    The objective of this study was to evaluate the phenotypic and genotypic profile of antimicrobial susceptibility and the possible involvement of extended spectrum beta-lactamases (ESBLs) in the resistance profile of Salmonella Heidelberg (SH) isolated from chicken meat. We used 18 SH isolates from chicken meat produced in 2013 in the state of Paraná, Southern Brazil. The isolates were submitted to disk-diffusion tests and from these results it was possible to determine the number of isolates considered multiresistant and the index of multiple antimicrobial resistance (IRMA) against ten antimicrobials routinely used in human and veterinary medicine. It was considered multidrug resistant the isolate that showed resistance to three or more classes of antibiotics. Another test performed was the disc-approximation in order to investigate interposed zones of inhibition, indicative of ESBLs production. In the isolates that presented multidrug resistance (18/18), a search of resistance genes involved in the production of ESBLs was performed using PCR: blaCMY-2, blaSHV-1, blaTEM-1, blaCTX-M2, blaOXA-1, blaPSE-1 and AmpC. The overall antimicrobial resistance was 80.55%. The highest levels of resistance were observed for nalidixic acid and ceftiofur (100%). The most commonly resistance pattern found (42.1%) was A (penicillin-cephalosporin-quinolone-tetracycline). The results were negative for ghost zone formation, indicative of ESBLs. However, PCR technique was able to detect resistance genes via ESBLs where the blaTEM-1 gene showed the highest amplification (83.33%), and the second most prevalent genes were blaCMY-2 (38.88%) and AmpC gene (38.88%). The blaOXA-1 and blaPSE-1 genes were not detected. These results are certainly of concern since SH is becoming more prevalent in the South of Brazil and able to cause severe disease in immune compromised individuals, showing high antimicrobial resistance to those drugs routinely used in the treatment and control of human and

  19. Anti-Microbial Resistance In Pakistan: A Public Health Issue

    Science.gov (United States)

    Shaikh, Babar Tasneem

    2017-01-01

    Anti-microbial or antibiotic resistance is a global public health problem, more dominant in the developing countries. Illiteracy and lack of awareness among the general population is a leading cause, compounded by lack of concern by the physicians and the pharmacists selling drugs over the counter. Another side of the phenomenon is attributed to profit making goals of pharmaceutical companies and weak regulation of the market. Nevertheless, misuse and overuse of antimicrobials accelerates this process. Besides, health issues, anti-microbial resistance also has economic implications on the health care system, where the simpler treatments are becoming difficult, day by day. Enforcement of standard treatment guidelines for the health providers and behavior changes at the patients’ end are likely to bring about a change in the situation.

  20. Mechanisms of resistance to antimicrobial peptides in staphylococci.

    Science.gov (United States)

    Joo, Hwang-Soo; Otto, Michael

    2015-11-01

    Staphylococci are commensal bacteria living on the epithelial surfaces of humans and other mammals. Many staphylococci, including the dangerous pathogen Staphylococcus aureus, can cause severe disease when they breach the epithelial barrier. Both during their commensal life and during infection, staphylococci need to evade mechanisms of innate host defense, of which antimicrobial peptides (AMPs) play a key role in particular on the skin. Mechanisms that staphylococci have developed to evade the bactericidal activity of AMPs are manifold, comprising repulsion of AMPs via alteration of cell wall and membrane surface charges, proteolytic inactivation, sequestration, and secretion. Furthermore, many staphylococci form biofilms, which represents an additional way of protection from antimicrobial agents, including AMPs. Finally, staphylococci can sense the presence of AMPs by sensor/regulator systems that control many of those resistance mechanisms. This article is part of a Special Issue entitled: Bacterial Resistance to Antimicrobial Peptides. Published by Elsevier B.V.

  1. Genotypic and phenotypic patterns of antimicrobial susceptibility of ...

    African Journals Online (AJOL)

    Marwa S. Fathi

    2013-04-22

    Apr 22, 2013 ... 100% and 25% for metronidazole and ciprofloxacin respectively from 16 isolated H. pylori strains. Improving the knowledge of resistance mechanisms, the elaboration of rational and efficacious associations for the treatment H. pylori infection are of high importance especially in determining the therapeutic ...

  2. Molecular characterization of antimicrobial resistance in clinical Shigella isolates during 2014 and 2015: trends in South India.

    Science.gov (United States)

    Anandan, Shalini; Muthuirulandi Sethuvel, Dhiviya Prabaa; Gajendiren, Revathi; Verghese, Valsan Philip; Walia, Kamini; Veeraraghavan, Balaji

    2017-09-01

    Shigella species are an important cause of acute diarrheal disease worldwide. This study describes the prevalence of Shigella spp. serotypes and their resistance profile in Vellore, South India from 2014 to 2015. From 2014 to 2015, 338 Shigella strains were isolated from stool samples at Christian Medical College, Vellore, India. Identification and serotyping was carried out using standard protocols. Antimicrobial susceptibility testing was done against commonly used antibiotics. Multidrug resistance was detected in 157 isolates. A subset of 73 isolates was randomly characterized further for acquired antimicrobial resistance genes in this study. The resistance profile of the study isolates varied by species and year. S. sonnei isolates were 100% resistant to all tested antibiotics in 2014, whereas in 2015, resistance was found for AMP-NAL-TAX-SXT-FIX. The resistance phenotypes among S. flexneri isolates for the year 2014 and 2015 were AMP-SXT-NAL-NOR-FIX-TAX and AMP-NAL-SXT-TAX-NOR-FIX respectively. Screening for antimicrobial resistance genes in S. flexneri found dhfr1A , sulII , bla OXA , bla TEM , bla CTX-M-1, qnr B, qnr S and AmpC genes while S. sonnei were found to have only dhfr1A , sulII, bla CTX-M-1 and qnr S genes respectively. Antimicrobial resistance genes were predominantly seen in AMP-SXT-NAL and AMP-SXT-NAL-NOR resistance phenotypes. Shigella prevalence of 4.8% to 4.6% was documented between the years 2014 to 2015 in this study. We show evidence that resistance to commonly used antibiotics continues to increase among Shigella spp. in South India. The presence of qnr S and bla CTX-M-15 in the study isolates further indicates the threat of spreading resistance to quinolones and third-generation cephalosporins.

  3. 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

  4. 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

    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

  5. 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...

  6. 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...... 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...... that there are multiple susceptible and resistant bacterial strains in the pig intestines, how can we describe their coexistence? To what extent does the composition of these multiple strains in individual pigs influence the total bacterial population of the pig pen? What happens to a complex population when...

  7. 76 FR 21907 - Draft Action Plan-A Public Health Action Plan To Combat Antimicrobial Resistance

    Science.gov (United States)

    2011-04-19

    ...-2011-0002] Draft Action Plan--A Public Health Action Plan To Combat Antimicrobial Resistance AGENCY... Antimicrobial Resistance (76 FR 14402). Written and electronic comments were to be received on or before April... Infectious Diseases, Division of Healthcare Quality Promotion, Office of Antimicrobial Resistance, Attn...

  8. 76 FR 14402 - Draft Action Plan-A Public Health Action Plan To Combat Antimicrobial Resistance

    Science.gov (United States)

    2011-03-16

    ...-2011-0002] Draft Action Plan--A Public Health Action Plan To Combat Antimicrobial Resistance AGENCY... requesting public comment on the draft A Public Health Action Plan to Combat Antimicrobial Resistance. HHS/CDC is publishing this notice on behalf of the HHS Interagency Task Force on Antimicrobial Resistance...

  9. Acid resistance, bile tolerance and antimicrobial properties of ...

    African Journals Online (AJOL)

    Maari is a fermented food condiment obtained by spontaneous fermentation of seeds from the baobab tree (Adansonia digitata). Nine dominant lactic acid bacteria (LAB) strains, isolated from traditional maari fermentation were examined for their resistance to pH 2.5, their tolerance to 0.3% bile and their antimicrobial ...

  10. Prevalence of antimicrobial resistance in Helicobacter pylori isolates ...

    African Journals Online (AJOL)

    Therefore, information concerning the prevalence of antimicrobial-resistant H. pylori strains is important in predicting therapeutic response. In this study, drug susceptibility of H. pylori in patients was investigated in Laleh hospital, Tehran, Iran from 2007 - 2008. 104 antral biopsies of patients with non ulcer dyspepsia and ...

  11. Antimicrobial resistance patterns in outpatient urinary tract infections ...

    African Journals Online (AJOL)

    Background. There is a global emergence of resistance against commonly prescribed antibiotics. Empirical antibiotic prescribing should be guided by local antimicrobial susceptibility patterns. Aim. To identify organisms and determine antibiotic susceptibility in urinary tract infections (UTIs) at 3 Military Hospital, Bloemfontein ...

  12. Antimicrobial resistance of bacterial isolates from urinary tract ...

    African Journals Online (AJOL)

    Urinary tract infections are common health problems and vary according to geography and regions. A retrospective analysis was conducted to determine the antimicrobial resistance of bacterial isolates from urine at Felege Hiwot Referral Hospital from September 2003 to June 2008. From 529 urine specimens, bacterial ...

  13. Persistence of antimicrobial resistance genes from sows to finisher pigs

    DEFF Research Database (Denmark)

    Birkegård, Anna Camilla; Halasa, Tariq; Folkesson, Anders

    2018-01-01

    Antimicrobial resistance in pigs has been under scrutiny for many years. However, many questions remain unanswered, including whether the initial antimicrobial resistance level of a pig will influence the antimicrobial resistance found at slaughter. Faecal samples from finishers pigs from 681 farms...... and from sows from 82 farms were collected, and levels of seven antimicrobial resistance genes, ermB, ermF, sulI, sulII, tet(M), tet(O), and tet(W), were quantified by high-capacity qPCR. There were 40 pairs of observations where the finishers were born in the farms of the sows. The objective of this study...... was to evaluate whether the levels of AMR genes found in finisher pigs at slaughter were associated with the levels in the farm where the finishers were born, and whether the levels of the AMR genes were equal in the sow and finisher pig populations. We found a significant positive correlation between the levels...

  14. Antimicrobial Resistance Pattern of Salmonella Isolates from Gondar ...

    African Journals Online (AJOL)

    Salmonellosis is a major health problem, especially in developing countries. Moreover, Salmonella species are becoming resistant to the commonly used antimicrobials in most parts of the world. Nevertheless, studies on Salmonella are limited in Ethiopia. The aim of this paper is, therefore to determine the antibiotic ...

  15. Antimicrobial resistance of non-clinical Escherichia coli strains from ...

    African Journals Online (AJOL)

    This study was carried out to determine resistance profiles of Escherichia coli strains isolated from clinically healthy chickens in Nsukka, southeast Nigeria. A total of 324 E. coli strains isolated from cloaca swabs from 390 chickens were tested against 16 antimicrobial agents using the disc diffusion method. The antibiotics ...

  16. Evolution of Pseudomonas aeruginosa Antimicrobial Resistance and Fitness under Low and High Mutation Rates.

    Science.gov (United States)

    Cabot, Gabriel; Zamorano, Laura; Moyà, Bartolomé; Juan, Carlos; Navas, Alfonso; Blázquez, Jesús; Oliver, Antonio

    2016-01-04

    Pseudomonas aeruginosa, a major cause of nosocomial and chronic infections, is considered a paradigm of antimicrobial resistance development. However, the evolutionary trajectories of antimicrobial resistance and the impact of mutator phenotypes remain mostly unexplored. Therefore, whole-genome sequencing (WGS) was performed in lineages of wild-type and mutator (ΔmutS) strains exposed to increasing concentrations of relevant antipseudomonal agents. WGS provided a privileged perspective of the dramatic effect of mutator phenotypes on the accumulation of random mutations, most of which were transitions, as expected. Moreover, a frameshift mutagenic signature, consistent with error-prone DNA polymerase activity as a consequence of SOS system induction, was also seen. This effect was evidenced for all antibiotics tested, but it was higher for fluoroquinolones than for cephalosporins or carbapenems. Analysis of genotype versus phenotype confirmed expected resistance evolution trajectories but also revealed new pathways. Classical mechanisms included multiple mutations leading to AmpC overexpression (ceftazidime), quinolone resistance-determining region (QRDR) mutations (ciprofloxacin), oprD inactivation (meropenem), and efflux pump overexpression (ciprofloxacin and meropenem). Groundbreaking findings included gain-of-function mutations leading to the structural modification of AmpC (ceftazidime), novel DNA gyrase (GyrA) modification (ciprofloxacin), and the alteration of the β-lactam binding site of penicillin-binding protein 3 (PBP3) (meropenem). A further striking finding was seen in the evolution of meropenem resistance, selecting for specific extremely large (>250 kb) genomic deletions providing a growth advantage in the presence of the antibiotic. Finally, fitness and virulence varied within and across evolved antibiotic-resistant populations, but mutator lineages showed a lower biological cost for some antibiotics. Copyright © 2016, American Society for

  17. The association between measurements of antimicrobial use and resistance in the faeces microbiota of finisher batches

    DEFF Research Database (Denmark)

    Dalhoff Andersen, Vibe; de Knegt, Leonardo; Munk, Patrick

    2017-01-01

    The objectives were to present three approaches for calculating antimicrobial (AM) use in pigs that take into account the rearing period and rearing site, and to study the association between these measurements and phenotypical resistance and abundance of resistance genes in faeces samples from 10...... finisher batches. The AM use was calculated relative to the rearing period of the batches as (i) 'Finisher Unit Exposure' at unit level, (ii) 'Lifetime Exposure' at batch level and (iii) 'Herd Exposure' at herd level. A significant effect on the occurrence of tetracycline resistance measured by cultivation...... effect was observed on the occurrence of genes coding for the AM resistance classes: aminoglycoside, lincosamide, macrolide, β-lactam, sulfonamide and tetracycline. No effect was observed for Finisher Unit Exposure. Overall, the study shows that Lifetime Exposure is an efficient measurement of AM use...

  18. Molecular determination of antimicrobial resistance in Escherichia coli isolated from raw meat in Addis Ababa and Bishoftu, Ethiopia.

    Science.gov (United States)

    Messele, Yohannes Equar; Abdi, Reta Duguma; Yalew, Shimels Tikuye; Tegegne, Desiye Tesfaye; Emeru, Bezina Arega; Werid, Gebremeskel Mamu

    2017-08-15

    Consumption of meat contaminated by E. coli causes a serious illness and even death to affected individuals. Recently the emerging of antibiotic resistant foodborne E. coli poses serious public health risks worldwide. However, little is known about the antibiotic resistance profile of E. coli in Ethiopia. This study aimed to determine the prevalence and Antimicrobial resistance (AMR) status of E. coli isolated from different type of meat. Overall 292 samples were collected from December 2015 to April 2016 from slaughterhouses to determine the prevalence and AMR of E. coli isolated from raw beef, mutton, chevon and chicken meat from Addis Ababa and Bishoftu, Ethiopia. The isolates were screened for AMR against commonly used antibiotics circulating in the Ethiopian market. Both phenotypic and genotypic approach were employed for AMR detection using disc diffusion test and PCR respectively. The prevalence of E. coli was 63 (21.6%), indicating one sample in every five samples harbors E. coli. Among these, the highest E. coli isolates was observed in chicken meat samples (37.0%; 27), followed by mutton (23.3%; 17), chevon (20.6%; 15) and beef (5.5%; 4). Results of disk diffusion test on the 63 isolates showed that only 4.8% of them were not resistance to all antimicrobials tested. Multiple drug resistance (resistance to ≥3 drugs) was 46.0%. Significantly high resistance to ampicillin (71.4%) and tetracycline (47.6%) was observed. Identification of genes associated with AMR was also done using PCR. The prevalence of E. coli isolates harboring resistance gene responsible for tetracycline (tet(A)), beta lactams (blaCMY) and sulphanamide (sulI) antibiotics were found 65.1, 65.1 and 54.0%, respectively. Twenty-five out of the 63 (39.7% %) E. coli isolates have got antimicrobial resistance gene to three or more classes of drugs. The associations of antimicrobial resistance phenotypes and resistance genes was also determined. The detection of resistance trait against

  19. Phenotypic, molecular characterization, antimicrobial susceptibility and draft genome sequence of Corynebacterium argentoratense strains isolated from clinical samples

    Directory of Open Access Journals (Sweden)

    I. Fernández-Natal

    2016-03-01

    Full Text Available During a 12-year period we isolated five Corynebacterium argentoratense strains identified by phenotypic methods, including the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF and 16S rRNA gene sequencing. In addition, antimicrobial susceptibility was determined, and genome sequencing for the detection of antibiotic resistance genes was performed. The organisms were isolated from blood and throat cultures and could be identified by all methods used. All strains were resistant to cotrimoxazole, and resistance to β-lactams was partly present. Two strains were resistant to erythromycin and clindamycin. The draft genome sequences of theses isolates revealed the presence of the erm(X resistance gene that is embedded in the genetic structure of the transposable element Tn5423. Although rarely reported as a human pathogen, C. argentoratense can be involved in bacteraemia and probably in other infections. Our results also show that horizontal transfer of genes responsible for antibiotic resistance is occurring in this species.

  20. Antimicrobial Resistance Profiles of the Two Porcine Salmonella Typhimurium Isolates

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    Kemal METİNER

    2016-07-01

    Full Text Available The aim of the study is to detect the presence of the Salmonella species in swine with diarrhea, and to investigate their antimicrobial resistance and extended spectrum beta lactamase (ESBL and/or AmpC β-lactamase production. For this purpose, stool samples from three commercial pig farms in Istanbul and Tekirdag were collected and processed for Salmonella isolation by culture and isolates were identified by biochemical activity tests. Salmonella isolates were confirmed by PCR then serotyped. Antimicrobial resistance and ESBL and AmpC production of the isolates were determined according to the Clinical and Laboratory Standards Institute (CLSI standard. In the study, two hundred and thirty eight stool samples were examined. Salmonella spp. were obtained from 2 samples, and the isolation rate was determined as 0.8%. Both of the isolates were defined as Salmonella enterica subsp. enterica serovar Typhimurium (serotype 1, 4, [5], 12: I: 1, 2 by serotyping. Both of them were resistant to cefaclor, cloxacillin and lincomycin (100%. Multidrug resistance (resistance ≥3 antimicrobials observed in all isolates. ESBL and AmpC production were not detected in any of the isolates. To our knowledge, this is the first report of the isolation of S. Typhimurium in pigs with diarrhea in Turkey. This study also represents the first report of multi-drug resistant S. Typhimurium isolates from pig stools in Turkey.

  1. 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...... genome shotgun sequencing as a method for predicting antimicrobial resistance properties, one meropenem resistant and five multidrug-resistant blood culture isolates were sequenced and antimicrobial resistance genes and IS elements identified using ResFinder 2.1 (http...

  2. Antimicrobial Susceptibility Patterns and Macrolide Resistance Genes of β-Hemolytic Viridans Group Streptococci in a Tertiary Korean Hospital

    Science.gov (United States)

    Hwang, Gyu Yel; Jang, In Ho; Kwon, Ohgun; Kim, Hyo Youl; Yoon, Kap Jun

    2007-01-01

    The aim of this study was to investigate antimicrobial susceptibilities and macrolide resistance mechanisms of β-hemolytic viridans group streptococci (VGS) in a tertiary Korean hospital. Minimum inhibitory concentrations (MICs) of seven antimicrobials were determined for 103 β-hemolytic VGS isolated from various specimens. The macrolide resistance mechanisms of erythromycin-resistant isolates were studied by the double disk test and polymerase chain reaction (PCR). The overall resistance rates of β-hemolytic VGS were found to be 47.5% to tetracycline, 3.9% to chloramphenicol, 9.7% to erythromycin, and 6.8% to clindamycin, whereas all isolates were susceptible to penicillin G, ceftriaxone, and vancomycin. Among ten erythromycin-resistant isolates, six isolates expressed a constitutive MLSB (cMLSB) phenotype, and each of the two isolates expressed the M phenotype, and the inducible MLSB (iMLSB) phenotype. The resistance rates to erythromycin and clindamycin of β-hemolytic VGS seemed to be lower than those of non-β-hemolytic VGS in our hospital, although cMLSB phenotype carrying erm(B) was dominant in β-hemolytic VGS. PMID:17982224

  3. Comparison of phenotypic and genotypic antimicrobial profiles in Eschericia coli and Salmonella enterica from the same dairy cattle farms

    OpenAIRE

    Scaria, Joy; Warnick, Lorin D; Kaneene, John B.; May, Katherine; Teng, Ching-Hao; Chang, Yung-Fu

    2010-01-01

    Transmission of antimicrobial drug resistance from resistant bacteria to non-resistant strains is an important public health issue. In this study, we have examined the possibility of multiple resistance gene transfer between Escherichia coli and Salmonella in the natural setting. Bacteria isolated from calves concurrently shedding E. coli and Salmonella showed similar antimicrobial drug resistance patterns as measured by a broth dilution method. However, microarray analysis of the antibiotic ...

  4. 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.

  5. Evolution of antimicrobial resistance of Salmonella enteritidis (1972–2005

    Directory of Open Access Journals (Sweden)

    Jermaine Khumalo

    2014-11-01

    Full Text Available With the extensive use of antibiotics in livestock production, surveillance revealed an increase in Salmonella resistance to the commonly used antimicrobials in veterinary and public health. This serious threat to health care is further exacerbated by the limited epidemiological information about the common zoonotic agent, Salmonella enteritidis, required to determine antibiotic therapy. The aim was to characterise the antimicrobial resistance patterns of S. enteritidis isolates across different timelines (1972–2005 with accompanying genetic changes being investigated. Thirty-seven stored S. enteritidis isolates were collected from the Central Veterinary Laboratory, Harare, with antimicrobial susceptibility determined against eight antibiotics. Plasmids were isolated to analyse any genetic variation. An overall significant increase in resistance (p < 0.05 to nalidixic acid (0% – 10%, ampicillin (14.3% – 50%, tetracycline (14.3% – 30% and erythromycin (71.4% – 100% was observed across the timeline. However, the highest rates of susceptibility were maintained for gentamicin, sulphamethoxazole-trimethoprim, kanamycin and chloramphenicol. We report an increase in multidrug resistance (MDR of 14.2% – 50% with an increase in resistotypes and plasmid profiles across the timeline. Eleven plasmid profiles were obtained in the 37 isolates studied with a minority of isolates (21.6%, 8/37 harbouring a 54 kb plasmid, commonly serovar-specific. A concerning increase in antimicrobial resistance to commonly administered drugs was observed across the timeline. The surge in MDR is of great concern and implies the need for consistent antimicrobial stewardship. No correlation was observed between the plasmid and antibiotic profiles.

  6. WGS accurately predicts antimicrobial resistance in Escherichia coli

    Science.gov (United States)

    Objectives: To determine the effectiveness of whole-genome sequencing (WGS) in identifying resistance genotypes of multidrug-resistant Escherichia coli (E. coli) and whether these correlate with observed phenotypes. Methods: Seventy-six E. coli strains were isolated from farm cattle and measured f...

  7. 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

    Staphylococcus pseudintermedius is a commensal and a common opportunistic pathogen causing mainly infections of the integumentary system in dogs. The recent emergence of multidrug-resistant S. pseudintermedius isolates, in particular methicillin-resistant strains (MRSP) is a threat to small animal...... health and highlights the need for antimicrobial resistance surveillance to detect trends and potentially perform timeous interventions. We systematically reviewed 202 published articles to investigate temporal changes in antimicrobial resistance in clinical and commensal S. pseudintermedius isolated...... 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...

  8. Inferring the interaction structure of resistance to antimicrobials.

    Science.gov (United States)

    Zawack, Kelson; Love, Will; Lanzas, Cristina; Booth, James G; Gröhn, Yrjö T

    2018-04-01

    The growth of antimicrobial resistance presents a significant threat to human and animal health. Of particular concern is multi-drug resistance, as this increases the chances an infection will be untreatable by any antibiotic. In order to understand multi-drug resistance, it is essential to understand the association between drug resistances. Pairwise associations characterize the connectivity between resistances and are useful in making decisions about courses of treatment, or the design of drug cocktails. Higher-order associations, interactions, which tie together groups of drugs can suggest commonalities in resistance mechanism and lead to their identification. To capture interactions, we apply log-linear models of contingency tables to analyze publically available data on the resistance of Escheresia coli isolated from chicken and turkey meat by the National Antimicrobial Resistance Monitoring System. Standard large sample and conditional exact testing approaches for assessing significance of parameters in these models breakdown due to structured patterns inherent to antimicrobial resistance. To address this, we adopt a Bayesian approach which reveals that E. coli resistance associations can be broken into two subnetworks. The first subnetwork is characterized by a hierarchy of β-lactams which is consistent across the chicken and turkey datasets. Tier one in this hierarchy is a near equivalency between amoxicillin-clavulanic acid, ceftriaxone and cefoxitin. Susceptibility to tier one then implies susceptibility to ceftiofur. The second subnetwork is characterized by more complex interactions between a variety of drug classes that vary between the chicken and turkey datasets. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Guideline recommendations and antimicrobial resistance: the need for a change.

    Science.gov (United States)

    Elias, Christelle; Moja, Lorenzo; Mertz, Dominik; Loeb, Mark; Forte, Gilles; Magrini, Nicola

    2017-07-26

    Antimicrobial resistance has become a global burden for which inappropriate antimicrobial use is an important contributing factor. Any decisions on the selection of antibiotics use should consider their effects on antimicrobial resistance. The objective of this study was to assess the extent to which antibiotic prescribing guidelines have considered resistance patterns when making recommendations for five highly prevalent infectious syndromes. We used Medline searches complemented with extensive use of Web engine to identify guidelines on empirical treatment of community-acquired pneumonia, urinary tract infections, acute otitis media, rhinosinusitis and pharyngitis. We collected data on microbiology and resistance patterns and identified discrete pattern categories. We assessed the extent to which recommendations considered resistance, in addition to efficacy and safety, when recommending antibiotics. We identified 135 guidelines, which reported a total of 251 recommendations. Most (103/135, 79%) were from developed countries. Community-acquired pneumonia was the syndrome mostly represented (51, 39%). In only 16 (6.4%) recommendations, selection of empirical antibiotic was discussed in relation to resistance and specific microbiological data. In a further 69 (27.5%) recommendations, references were made in relation to resistance, but the attempt was inconsistent. Across syndromes, 12 patterns of resistance with implications on recommendations were observed. 50% to 75% of recommendations did not attempt to set recommendation in the context of these patterns. There is consistent evidence that guidelines on empirical antibiotic use did not routinely consider resistance in their recommendations. Decision-makers should analyse and report the extent of local resistance patterns to allow better decision-making. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless

  10. 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.

  11. 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. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  12. Associations of antimicrobial use with antimicrobial resistance in Campylobacter coli from grow-finish pigs in Japan.

    Science.gov (United States)

    Ozawa, M; Makita, K; Tamura, Y; Asai, T

    2012-10-01

    To determine associations between antimicrobial use and antimicrobial resistance in Campylobacter coli, 155 isolates were obtained from the feces of apparently healthy grow-finish pigs in Japan. In addition, data on the use of antibiotics collected through the national antimicrobial resistance monitoring system in Japan were used for the analysis. Logistic regression was used to identify risk factors to antimicrobial resistance in C. coli in pigs for the following antimicrobials: ampicillin, dihydrostreptomycin, erythromycin, oxytetracycline, chloramphenicol, and enrofloxacin. The data suggested the involvement of several different mechanisms of resistance selection. The statistical relationships were suggestive of co-selection; use of macrolides was associated with enrofloxacin resistance (OR=2.94; CI(95%): 0.997, 8.68) and use of tetracyclines was associated with chloramphenicol resistance (OR=2.37; CI(95%): 1.08, 5.19). The statistical relationships were suggestive of cross-resistance: use of macrolides was associated with erythromycin resistance (OR=9.36; CI(95%): 2.96, 29.62) and the use of phenicols was associated with chloramphenicol resistance (OR=11.83; CI(95%): 1.41, 99.44). These data showed that the use of antimicrobials in pigs selects for resistance in C. coli within and between classes of antimicrobials. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Understanding media publics and the antimicrobial resistance crisis.

    Science.gov (United States)

    Davis, Mark; Whittaker, Andrea; Lindgren, Mia; Djerf-Pierre, Monika; Manderson, Lenore; Flowers, Paul

    2017-06-08

    Antimicrobial resistance (AMR) imperils health for people across the world. This enormous challenge is being met with the rationalisation of prescription, dispensing and consumption of antimicrobials in clinical settings and in the everyday lives of members of the general population. Individuals need to be reached outside clinical settings to prepare them for the necessary changes to the pharmaceutical management of infections; efforts that depend on media and communications and, therefore, how the AMR message is mediated, received and applied. In 2016, the UK Review on Antimicrobial Resistance called on governments to support intense, worldwide media activity to promote public awareness and to further efforts to rationalise the use of antimicrobial pharmaceuticals. In this article, we consider this communications challenge in light of contemporary currents of thought on media publics, including: the tendency of health communications to cast experts and lay individuals in opposition; the blaming of individuals who appear to 'resist' expert advice; the challenges presented by negative stories of AMR and their circulation in public life, and; the problems of public trust tied to the construction and mediation of expert knowledge on the effective management of AMR.

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

    Directory of Open Access Journals (Sweden)

    Wei WANG

    2011-03-01

    Full Text Available Antimicrobial 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 Xanthomonas 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.

  15. Bacterial resistance and susceptibility to antimicrobial peptides and peptidomimetics

    DEFF Research Database (Denmark)

    Citterio, Linda

    Bacterial resistance to conventional antibiotics has become a global challenge and there is urgent need for new and alternative compounds. Antimicrobial peptides (AMPs) are under investigation as novel antibiotics. These are part of the immune defense of all living organisms; hence, they represen...... be a threat to our immunity may be overestimated. In conclusion, this PhD project supports the belief that bacteria hold the potential to develop resistance to each novel antibacterial agent. Nevertheless, strategies to circumvent resistance exist and must be pursued.......Bacterial resistance to conventional antibiotics has become a global challenge and there is urgent need for new and alternative compounds. Antimicrobial peptides (AMPs) are under investigation as novel antibiotics. These are part of the immune defense of all living organisms; hence, they represent...... are one class of such synthetic modified peptides. The purpose of this PhD project was to determine the antibacterial spectrum and potential use of synthetic antimicrobial peptides and peptidomimetics. Another key investigation has been the experimental development of resistance to these novel...

  16. Antimicrobial resistance patterns in Danish isolates of Flavobacterium psychrophilum

    DEFF Research Database (Denmark)

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

    2000-01-01

    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...... 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...... years. Apparently, F. psychrophilum carries intrinsic resistance towards the potentiated sulfonamides, and in correlation with this, we found very few susceptible isolates, All isolates were susceptible to FLO. The method used for determining minimum inhibitory concentration (MIC) follows the American...

  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....... intermedius and Proteus isolates. Conclusions: This investigation provided data on occurrence of antimicrobial resistance in important pathogenic bacteria from dogs, which may be useful for the small animal practitioner. Resistance was low to the compounds that were most often used, but unfortunately......, these compounds were broad-spectrum. Data on resistance and usage may form a background for the establishment of a set of recommendations for prudent use of antimicrobials for companion animals....

  18. Phenotypic occurrence of methicillin-resistant Staphylococcus ...

    African Journals Online (AJOL)

    ADEYEYE

    2017-03-13

    Mar 13, 2017 ... Because of the ability of the staphylococci to change resistance pattern over time, MRSA may continue to be a problem in the future. In Africa, relatively high prevalence rates of MRSA have been reported especially in Nigeria, Kenya and Cameroon (20-76%) and below 10% in Tunisia and Algeria (Nwanko ...

  19. Phenotypic occurrence of methicillin-resistant Staphylococcus ...

    African Journals Online (AJOL)

    To assess the occurrence of MRSA among camels in Kano abattoir, a total of 300 nasal swabs were collected from camels at the lairage in Kano abattoir, Kano state, Nigeria to isolate and biochemically characterize Staphylococcus aureus and confirm methicillin-resistant Staphylococcus aureus among isolates using ...

  20. 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.

  1. Antimicrobial Resistance Risks of Cholera Prophylaxis for United Nations Peacekeepers.

    Science.gov (United States)

    Kunkel, Amber; Lewnard, Joseph A; Pitzer, Virginia E; Cohen, Ted

    2017-08-01

    More than 5 years after a United Nations peacekeeping battalion introduced cholera to Haiti, over 150,000 peacekeepers continue to be deployed annually from countries where cholera is endemic. The United Nations has thus far declined to provide antimicrobial chemoprophylaxis to peacekeepers, a policy based largely on concerns that the risks of drug resistance generation and spread would outweigh the potential benefits of preventing future cholera importations. In this study, we sought to better understand the relative benefits and risks of cholera chemoprophylaxis for peacekeepers in terms of antibiotic resistance. Using a stochastic model to quantify the potential impact of chemoprophylaxis on importation and transmission of drug-resistant and drug-sensitive Vibrio cholerae , we found that chemoprophylaxis would decrease the probability of cholera importation but would increase the expected number of drug-resistant infections if an importation event were to occur. Despite this potential increase, we found that at least 10 drug-sensitive infections would likely be averted per excess drug-resistant infection under a wide range of assumptions about the underlying prevalence of drug resistance and risk of acquired resistance. Given these findings, policymakers should reconsider whether the potential resistance risks of providing antimicrobial chemoprophylaxis to peacekeepers are sufficient to outweigh the anticipated benefits. Copyright © 2017 American Society for Microbiology.

  2. In Vitro Synergistic Effect of Psidium guineense (Swartz in Combination with Antimicrobial Agents against Methicillin-Resistant Staphylococcus aureus Strains

    Directory of Open Access Journals (Sweden)

    Tiago Gomes Fernandes

    2012-01-01

    Full Text Available The aim of this study was to evaluate the antimicrobial activity of aqueous extract of Psidium guineense Swartz (Araçá-do-campo and five antimicrobials (ampicillin, amoxicillin/clavulanic acid, cefoxitin, ciprofloxacin, and meropenem against twelve strains of Staphylococcus aureus with a resistant phenotype previously determined by the disk diffusion method. Four S. aureus strains showed resistance to all antimicrobial agents tested and were selected for the study of the interaction between aqueous extract of P. guineense and antimicrobial agents, by the checkerboard method. The criteria used to evaluate the synergistic activity were defined by the fractional inhibitory concentration index (FICI. All S. aureus strains were susceptible to P. guineense as determined by the microdilution method. The combination of the P. guineense extract with the antimicrobial agents resulted in an eight-fold reduction in the MIC of these agents, which showed a FICI ranging from 0.125 to 0.5, suggesting a synergistic interaction against methicillin-resistant Staphylococcus aureus (MRSA strains. The combination of the aqueous extract of P. guineense with cefoxitin showed the lowest FICI values. This study demonstrated that the aqueous extract of P. guineense combined with beta lactamics antimicrobials, fluoroquinolones, and carbapenems, acts synergistically by inhibiting MRSA strains.

  3. Antimicrobial resistance, virulence genes and PFGE-profiling of Escherichia coli isolates from South Korean cattle farms.

    Science.gov (United States)

    Shin, Seung Won; Byun, Jae-Won; Jung, Myounghwan; Shin, Min-Kyoung; Yoo, Han Sang

    2014-09-01

    To estimate the prevalence of Escherichia coli with potential pathogenicity in cattle farm in South Korea, a total of 290 E. coli isolates were isolated from cattle farms over a period of 2 years in South Korea. These were examined for phenotypic and genotypic characteristics including antimicrobial susceptibility, serotype, and gene profiles of virulence and antimicrobial resistance. The most dominant virulence gene was f17 (26.2%), followed by stx2 (15.9%), ehxA (11.0%), stx1 (8.3%), eae (5.2%), and sta (4.1%). Some shiga-toxin producing E. coli isolates possessed eae (15.9%). All isolates except for one showed resistance to one or more antimicrobials, with 152 isolates exhibiting multidrug-resistance. The most prevalent resistance phenotype detected was streptomycin (63.1%), followed by tetracycline (54.5%), neomycin (40.3%), cephalothin (32.8%), amoxicillin (30.0%), ampicillin (29.7%), and sulphamethoxazole/trimethoprim (16.6%). The associated resistance determinants detected were strA-strB (39.0%), tet(E) (80.0%), tet(A) (27.6%), aac(3)-IV (33.1%), aphA1 (21.4%), bla TEM (23.8%), and sul2 (22.1%). When investigated by O serotyping and PFGE molecular subtyping, the high degree of diversity was exhibited in E. coli isolates. These results suggest that E. coli isolates from South Korean cattle farms are significantly diverse in terms of virulence and antimicrobial resistance. In conclusion, the gastroinstestinal flora of cattle could be a significant reservoir of diverse virulence and antimicrobial resistance determinants, which is potentially hazardous to public health.

  4. Antimicrobial resistance and virulence-related genes of Streptococcus obtained from dairy cows with mastitis in Inner Mongolia, China.

    Science.gov (United States)

    Ding, Yuexia; Zhao, Junli; He, Xiuling; Li, Man; Guan, Hong; Zhang, Ziying; Li, Peifeng

    2016-01-01

    Mastitis is the most expensive disease in the dairy cattle industry and results in decreased reproductive performance. Streptococcus, especially Streptococcus agalactiae, possesses a variety of virulence factors that contribute to pathogenicity. Streptococcus isolated from mastitis was tested to assess the prevalence of antimicrobial resistance and distribution of antibiotic resistance- and virulence-related genes. Eighty-one Streptococcus isolates were phenotypically characterized for antimicrobial resistance against 15 antibiotics by determining minimum inhibitory concentrations (MIC) using a micro-dilution method. Resistance- and virulence-related genes were detected by PCR. High percentage of resistance to β-lactams, along with tetracycline and erythromycin, was found. Resistance to three or more of seven antimicrobial agents was observed at 88.9%, with penicillin-tetracycline-erythromycin-clindamycin as the major profile in Streptococcus isolates. Resistant genes were detected by PCR, the result showed that 86.4, 86.4, 81.5, and 38.3% of isolates were mainly carrying the pbp2b, tetL, tetM, and ermB genes, respectively. Nine virulence genes were investigated. Genes cyl, glnA, cfb, hylB, and scaA were found to be in 50% of isolates, while 3.7, 21, and 4.9% of isolates were positive for bca, lmb, and scpB, genes, respectively. None of the isolates carried the bac gene. This study suggests the need for prudent use of antimicrobial agents in veterinary clinical medicine to avoid the increase and dissemination of antimicrobial resistance arising from the use of antimicrobial drugs in animals.

  5. Antimicrobial resistance of coagulase-negative staphylococci and lactic acid bacteria from industrially produced dairy products

    Directory of Open Access Journals (Sweden)

    Nevijo Zdolec

    2013-03-01

    Full Text Available In this research, the susceptibility to clindamycin, tetracycline, amikacin, amoxicillin + clavulanic acid, enrofloxacine, vancomycin, trimethoprim + sulphametoxazol, tobramycin, chloramphenicol, ciprofloxacin, erythromycin, penicillin and trimethoprim was tested in coagulase-negative staphylococci (n=78 and lactic acid bacteria (n=30 by means of disk diffusion test and E-test. The isolates were collected from soft and hard cheeses, butter and brine. All isolates of coagulase-negative staphylococci were susceptible to clindamycin, amikacin, amoxicillin + clavulanic acid, enrofloxacine, vancomycin, chloramphenicol and ciprofloxacin according to CLSI breakpoints. A total of 30 staphylococci isolates (38.46 % were resistant to erythromycin, 18 to penicillin (23.07 %, 4 to tetracycline (5.12 %, and one isolate to trimethoprim, tobramicin and trimethoprim + sulphametoxazol (1.28 %. Among 78 tested staphylococci, 35 of them were resistant to at least one antimicrobial substance (44.87 %. The rate of resistant isolates of different soft cheese types ranged from 22 to 70 %, while resistant staphylococci were absent in hard cheese and brine. The growth of lactic acid bacteria was not influenced by trimethoprim + sulphametoxazol (n=29, vancomycin (n=29, trimethoprim (n=28, amikacin (n=10 and tobramycin (n=10. The results show that significant part of apathogenic microbiota in different dairy products is phenotypically resistant to antimicrobial agents.

  6. Control and monitoring of antimicrobial resistance in bacteria in food-producing animals in Japan

    Directory of Open Access Journals (Sweden)

    Katsuaki Sugiura

    2009-06-01

    Full Text Available Increased antimicrobial resistance in bacteria that cause infections in humans is a threat to public health. The use of antimicrobials in food-producing animals in the form of veterinary medicine and feed additives may lead to the emergence or spread of antimicrobial resistance in bacteria of animal origin. In Japan, the use of antimicrobials in food-producing animals is regulated by the Pharmaceutical Affairs Law and Feed Safety Law to minimise the risk of emergence and spread of antimicrobial resistance in bacteria. Since December 2003, all antimicrobials used in food-producing animals have been subjected to risk assessment by the Food Safety Commission. In addition, an antimicrobial resistance monitoring programme has been in place since 2000 to monitor the evolution of resistance to different antimicrobials in bacteria in food-producing animals.

  7. Antimicrobial Peptide Resistance Mechanisms of Gram-Positive Bacteria.

    Science.gov (United States)

    Nawrocki, Kathryn L; Crispell, Emily K; McBride, Shonna M

    2014-10-13

    Antimicrobial peptides, or AMPs, play a significant role in many environments as a tool to remove competing organisms. In response, many bacteria have evolved mechanisms to resist these peptides and prevent AMP-mediated killing. The development of AMP resistance mechanisms is driven by direct competition between bacterial species, as well as host and pathogen interactions. Akin to the number of different AMPs found in nature, resistance mechanisms that have evolved are just as varied and may confer broad-range resistance or specific resistance to AMPs. Specific mechanisms of AMP resistance prevent AMP-mediated killing against a single type of AMP, while broad resistance mechanisms often lead to a global change in the bacterial cell surface and protect the bacterium from a large group of AMPs that have similar characteristics. AMP resistance mechanisms can be found in many species of bacteria and can provide a competitive edge against other bacterial species or a host immune response. Gram-positive bacteria are one of the largest AMP producing groups, but characterization of Gram-positive AMP resistance mechanisms lags behind that of Gram-negative species. In this review we present a summary of the AMP resistance mechanisms that have been identified and characterized in Gram-positive bacteria. Understanding the mechanisms of AMP resistance in Gram-positive species can provide guidelines in developing and applying AMPs as therapeutics, and offer insight into the role of resistance in bacterial pathogenesis.

  8. 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...... gradually decreased. Chlorhexidine also gradually reduced biofilm cell number, but was inhibitory at concentrations closer to the MIC than was the case for the antibiotics. Thus S. sanguis in biofilms survived up to 500 times the MIC found in batch culture for up to 48 h....

  9. 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...... in aquaculture ponds. Concerns have been raised that the declared information on probiotic product labels are incorrect and information on bacterial composition are often missing. We therefore evaluated seven probiotics commonly used in Vietnamese shrimp culture for their bacterial species content, phenotypic....... 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...

  10. Antimicrobial Resistance of Enteric Salmonella in Bangui, Central African Republic

    Directory of Open Access Journals (Sweden)

    Christian Diamant Mossoro-Kpinde

    2015-01-01

    Full Text Available Introduction. The number of Salmonella isolated from clinical samples that are resistant to multiple antibiotics has increased worldwide. The aim of this study was to determine the prevalence of resistant Salmonella enterica isolated in Bangui. Methods. All enteric Salmonella strains isolated from patients in 2008 were identified and serotyped, and the phenotypes of resistance were determined by using the disk diffusion method. Nine resistance-associated genes, blaTEM, blaOXA, blaSHV, tetA, aadA1, catA1, dhfrA1, sul I, and sul II, were sought by genic amplification in seven S.e. Typhimurium strains. Results. The 94 strains isolated consisted of 47 S.e. Typhimurium (50%, 21 S.e. Stanleyville (22%, 18 S.e. Enteritidis (19%, 4 S.e. Dublin (4%, 4 S.e. Hadar (4%, and 1 S.e. Papuana (1%. Twenty-five (28% were multiresistant, including 20 of the Typhimurium serovar (80%. Two main phenotypes of resistance were found: four antibiotics (56% and to five antibiotics (40%. One S.e. Typhimurium isolate produced an extended-spectrum β-lactamase (ESBL. Only seven strains of S.e. Typhimurium could be amplified genically. Only phenotypic resistance to tetracycline and aminosides was found. Conclusion. S. Typhimurium is the predominant serovar of enteric S. enterica and is the most widely resistant. The search for resistance genes showed heterogeneity of the circulating strains.

  11. Antimicrobial Resistance Profiles of Listeria monocytogenes and Listeria innocua Isolated from Ready-to-Eat Products of Animal Origin in Spain.

    Science.gov (United States)

    Escolar, Cristina; Gómez, Diego; Del Carmen Rota García, María; Conchello, Pilar; Herrera, Antonio

    2017-06-01

    The objective of this work was to investigate the antimicrobial resistance in Listeria spp. isolated from food of animal origin. A total of 50 Listeria strains isolated from meat and dairy products, consisting of 7 Listeria monocytogenes and 43 Listeria innocua strains, were characterized for antimicrobial susceptibility against nine antimicrobials. The strains were screened by real-time PCR for the presence of antimicrobial resistance genes: tet M, tet L, mef A, msr A, erm A, erm B, lnu A, and lnu B. Multidrug resistance was identified in 27 Listeria strains, 4 belonging to L. monocytogenes. Resistance to clindamycin was the most common resistance phenotype and was identified in 45 Listeria strains; the mechanisms of resistance are still unknown. A medium prevalence of resistance to tetracycline (15 and 9 resistant and intermediate strains) and ciprofloxacin (13 resistant strains) was also found. Tet M was detected in Listeria strains with reduced susceptibility to tetracycline, providing evidence that both L. innocua and L. monocytogenes displayed acquired resistance. The presence of antimicrobial resistance genes in L. innocua and L. monocytogenes indicates that these genes may be transferred to commensal and pathogenic bacteria via the food chain; besides this, antibiotic resistance in L. monocytogenes could compromise the effective treatment of listeriosis in humans.

  12. 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. © 2015 Pharmacotherapy Publications, Inc.

  13. Simple method to determine beta-lactam resistance phenotypes in Pseudomonas aeruginosa using the disc agar diffusion test.

    Science.gov (United States)

    Vedel, G

    2005-10-01

    Pseudomonas aeruginosa is a major opportunistic bacterial pathogen in nosocomial infections because of the increasing prevalence of resistance to many of the commonly used antibiotics. To ensure optimal efficiency of antibiotic treatment against this species, antibiotic susceptibility tests must be interpreted with caution. Most microbiologists now consider it essential to characterize the antibiotic resistance expressed by isolates. Particular resistance mechanisms may be suspected when the bacterium is resistant to several antibiotics in the same family (for example beta-lactam agents). Using the disc agar diffusion test, a simple method was developed to distinguish between the common beta-lactam resistance phenotypes of P. aeruginosa and, consequently, the possible resistance mechanism(s). Over a period of 5 years, we analysed 6300 P. aeruginosa strains isolated from various pathological specimens collected from different wards of Cochin Port-Royal Hospital, and reference and collection strains. Each strain had the wild-type phenotype or an acquired resistance phenotype. Eight anti-pseudomonal beta-lactams (ticarcillin, cefotaxime or moxalactam, cefepime or cefpirome, imipenem, ceftazidime, aztreonam, cefsulodin and ticarcillin + clavulanic acid) were used as phenotypic markers. The following markers were sufficient to distinguish between the wild-type phenotype and the various acquired resistance phenotypes: beta-lactamase synthesis, reduced cell wall permeability and/or increased expression of efflux transporters (active efflux). Detection of resistance phenotypes allows 'interpretive reading' of antibiotic susceptibility tests. Clearly, improved interpretation of antibiotic susceptibility tests is important for a better appreciation of the effect of antimicrobial agents on bacteria such as P. aeruginosa.

  14. Antimicrobial resistance risk factors and characterisation of faecal E. coli isolated from healthy Labrador retrievers in the United Kingdom.

    Science.gov (United States)

    Schmidt, Vanessa M; Pinchbeck, Gina L; Nuttall, Tim; McEwan, Neil; Dawson, Susan; Williams, Nicola J

    2015-04-01

    Antimicrobial resistant bacteria are increasingly detected from canine samples but few studies have examined commensal isolates in healthy community dogs. We aimed to characterise faecal Escherichia coli from 73 healthy non-veterinarian-visiting and non-antimicrobial treated Labrador retrievers, recruited from dog shows in the North West United Kingdom between November 2010 and June 2011. Each enrolled dog provided one faecal sample for our study. E. coli were isolated from 72/73 (99%) faecal samples. Disc diffusion susceptibility tests were determined for a range of antimicrobials, including phenotypic extended-spectrum beta-lactamase (ESBL) and AmpC-production. PCR assay detected phylogenetic groups and resistance genes (blaCTX-M, blaSHV, blaTEM, blaOXA, blaCIT, qnr), and conjugation experiments were performed to investigate potential transfer of mobile genetic elements. Multivariable logistic regression examined potential risk factors from owner-questionnaires for the presence of antimicrobial resistant faecal E. coli. Antimicrobial resistant, multi-drug resistant (≥3 antimicrobial classes; MDR) and AmpC-producing E. coli were detected in 63%, 30% and 16% of samples, respectively. ESBL-producing E. coli was detected from only one sample and conjugation experiments found that blaCTX-M and blaCIT were transferred from commensal E. coli to a recipient strain. Most isolates were phylogenetic groups B1 and A. Group B2 isolates were associated with lower prevalence of resistance to at least one antimicrobial (Presistance (3GCR) (OR: 10.9; 95% CI: 2.2-54.0). AMR E. coli were surprisingly prevalent in this group of non-antimicrobial treated and non-veterinarian-visiting dogs and consumption of raw meat was a significant risk factor for antimicrobial resistance. These findings are of concern due to the increasing popularity of raw-meat canine diets, and the potential for opportunistic infection, zoonotic transmission and transmission of antimicrobial resistant

  15. Phenotypic and genotypic characterization of vancomycin-resistant Enterococcus faecium clinical isolates from two hospitals in Mexico: First detection of VanB phenotype-vanA genotype.

    Science.gov (United States)

    Bocanegra-Ibarias, Paola; Flores-Treviño, Samantha; Camacho-Ortiz, Adrián; Morfin-Otero, Rayo; Villarreal-Treviño, Licet; Llaca-Díaz, Jorge; Martínez-Landeros, Erik Alan; Rodríguez-Noriega, Eduardo; Calzada-Güereca, Andrés; Maldonado-Garza, Héctor Jesús; Garza-González, Elvira

    2016-01-01

    Enterococcus faecium has emerged as a multidrug-resistant nosocomial pathogen involved in outbreaks worldwide. Our aim was to determine the antimicrobial susceptibility, biofilm production, and clonal relatedness of vancomycin-resistant E. faecium (VREF) clinical isolates from two hospitals in Mexico. Consecutive clinical isolates (n=56) were collected in two tertiary care hospitals in Mexico from 2011 to 2014. VREF isolates were characterized by phenotypic and molecular methods including pulsed-field gel electrophoresis (PFGE). VREF isolates were highly resistant to vancomycin, erythromycin, norfloxacin, high-level streptomycin, and teicoplanin, and showed lower resistance to tetracycline, nitrofurantoin and quinupristin-dalfopristin. None of the isolates were resistant to linezolid. The vanA gene was detected in all isolates. Two VanB phenotype-vanA genotype isolates, highly resistant to vancomycin and susceptible to teicoplanin, were detected. Furthermore, 17.9% of the isolates were classified as biofilm producers, and the espfm gene was found in 98.2% of the isolates. A total of 37 distinct PFGE patterns and 6 clones (25% of the isolates as clone A, 5.4% as clone B, and 3.6% each as clone C, D, E, and F) were detected. Clone A was detected in 5 different wards of the same hospital during 14 months of surveillance. The high resistance to most antimicrobial agents and the moderate cross-transmission of VREF detected accentuates the need for continuous surveillance of E. faecium in the hospital setting. This is also the first reported incidence of the E. faecium VanB phenotype-vanA genotype in the Americas. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  16. Search Engine for Antimicrobial Resistance: A Cloud Compatible Pipeline and Web Interface for Rapidly Detecting Antimicrobial Resistance Genes Directly from Sequence Data.

    Science.gov (United States)

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

    2015-01-01

    Antimicrobial resistance remains a growing and significant concern in human and veterinary medicine. Current laboratory methods for the detection and surveillance of antimicrobial resistant bacteria are limited in their effectiveness and scope. With the rapidly developing field of whole genome sequencing beginning to be utilised in clinical practice, the ability to interrogate sequencing data quickly and easily for the presence of antimicrobial resistance genes will become increasingly important and useful for informing clinical decisions. Additionally, use of such tools will provide insight into the dynamics of antimicrobial resistance genes in metagenomic samples such as those used in environmental monitoring. Here we present the Search Engine for Antimicrobial Resistance (SEAR), a pipeline and web interface for detection of horizontally acquired antimicrobial resistance genes in raw sequencing data. The pipeline provides gene information, abundance estimation and the reconstructed sequence of antimicrobial resistance genes; it also provides web links to additional information on each gene. The pipeline utilises clustering and read mapping to annotate full-length genes relative to a user-defined database. It also uses local alignment of annotated genes to a range of online databases to provide additional information. We demonstrate SEAR's application in the detection and abundance estimation of antimicrobial resistance genes in two novel environmental metagenomes, 32 human faecal microbiome datasets and 126 clinical isolates of Shigella sonnei. We have developed a pipeline that contributes to the improved capacity for antimicrobial resistance detection afforded by next generation sequencing technologies, allowing for rapid detection of antimicrobial resistance genes directly from sequencing data. SEAR uses raw sequencing data via an intuitive interface so can be run rapidly without requiring advanced bioinformatic skills or resources. Finally, we show that SEAR

  17. Search Engine for Antimicrobial Resistance: A Cloud Compatible Pipeline and Web Interface for Rapidly Detecting Antimicrobial Resistance Genes Directly from Sequence Data.

    Directory of Open Access Journals (Sweden)

    Will Rowe

    Full Text Available Antimicrobial resistance remains a growing and significant concern in human and veterinary medicine. Current laboratory methods for the detection and surveillance of antimicrobial resistant bacteria are limited in their effectiveness and scope. With the rapidly developing field of whole genome sequencing beginning to be utilised in clinical practice, the ability to interrogate sequencing data quickly and easily for the presence of antimicrobial resistance genes will become increasingly important and useful for informing clinical decisions. Additionally, use of such tools will provide insight into the dynamics of antimicrobial resistance genes in metagenomic samples such as those used in environmental monitoring.Here we present the Search Engine for Antimicrobial Resistance (SEAR, a pipeline and web interface for detection of horizontally acquired antimicrobial resistance genes in raw sequencing data. The pipeline provides gene information, abundance estimation and the reconstructed sequence of antimicrobial resistance genes; it also provides web links to additional information on each gene. The pipeline utilises clustering and read mapping to annotate full-length genes relative to a user-defined database. It also uses local alignment of annotated genes to a range of online databases to provide additional information. We demonstrate SEAR's application in the detection and abundance estimation of antimicrobial resistance genes in two novel environmental metagenomes, 32 human faecal microbiome datasets and 126 clinical isolates of Shigella sonnei.We have developed a pipeline that contributes to the improved capacity for antimicrobial resistance detection afforded by next generation sequencing technologies, allowing for rapid detection of antimicrobial resistance genes directly from sequencing data. SEAR uses raw sequencing data via an intuitive interface so can be run rapidly without requiring advanced bioinformatic skills or resources. Finally, we

  18. 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.

  19. Frequency, Antimicrobial Resistance and Genetic Diversity of Klebsiella pneumoniae in Food Samples.

    Directory of Open Access Journals (Sweden)

    Yumei Guo

    Full Text Available This study aimed to assess the frequency of Klebsiella pneumoniae in food samples and to detect antibiotic resistance phenotypes, antimicrobial resistance genes and the molecular subtypes of the recovered isolates. A total of 998 food samples were collected, and 99 (9.9% K. pneumoniae strains were isolated; the frequencies were 8.2% (4/49 in fresh raw seafood, 13.8% (26/188 in fresh raw chicken, 11.4% (34/297 in frozen raw food and 7.5% (35/464 in cooked food samples. Antimicrobial resistance was observed against 16 antimicrobials. The highest resistance rate was observed for ampicillin (92.3%, followed by tetracycline (31.3%, trimethoprim-sulfamethoxazole (18.2%, and chloramphenicol (10.1%. Two K. pneumoniae strains were identified as extended-spectrum β-lactamase (ESBL-one strain had three beta-lactamases genes (blaSHV, blaCTX-M-1, and blaCTX-M-10 and one had only the blaSHV gene. Nineteen multidrug-resistant (MDR strains were detected; the percentage of MDR strains in fresh raw chicken samples was significantly higher than in other sample types (P<0.05. Six of the 18 trimethoprim-sulfamethoxazole-resistant strains carried the folate pathway inhibitor gene (dhfr. Four isolates were screened by PCR for quinolone resistance genes; aac(6'-Ib-cr, qnrB, qnrA and qnrS were detected. In addition, gyrA gene mutations such as T247A (Ser83Ile, C248T (Ser83Phe, and A260C (Asp87Ala and a parC C240T (Ser80Ile mutation were identified. Five isolates were screened for aminoglycosides resistance genes; aacA4, aacC2, and aadA1 were detected. Pulsed-field gel electrophoresis-based subtyping identified 91 different patterns. Our results indicate that food, especially fresh raw chicken, is a reservoir of antimicrobial-resistant K. pneumoniae, and the potential health risks posed by such strains should not be underestimated. Our results demonstrated high prevalence, antibiotic resistance rate and genetic diversity of K. pneumoniae in food in China. Improved

  20. Multidrug Resistant Acinetobacter Infection and Their Antimicrobial ...

    African Journals Online (AJOL)

    Background: Acinetobacter baumannii, a non-glucose fermenting Gram negative bacillus, has emerged in the last three decades as a major etiological agent of hospital-associated infections giving rise to significant morbidity and mortality particularly in immunocompromised patients. Multidrug resistant A. baumannii ...

  1. 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

  2. Molecular Characterisation and Antimicrobial Resistance Patterns of ...

    African Journals Online (AJOL)

    East African Medical Journal ... Methods: A Total of 400 slaughtered goats which were inspected by veterinary health officers and approved for human consumption were sampled from Huruma ... This indicates that goat meat from abattoirs could pose a risk of transmission of pathogenic antibiotic resistant strains to human.

  3. Prevalence, Risk Factors and Antimicrobial Resistance of ...

    African Journals Online (AJOL)

    Mubeen

    and Gram-positive bacteria. KEY WORDS: Antenatal women, antibiotic resistance, asymptomatic bacteriuria, prevalence, risk factors. INTRODUCTION. Urinary tract infection (UTI) during pregnancy is classified as either symptomatic or asymptomatic. Symptomatic UTI are divided into lower tract (acute cystitis) and upper ...

  4. antimicrobial resistance patterns and plasmid profiles

    African Journals Online (AJOL)

    hi-tech

    2000-09-01

    Sep 1, 2000 ... College of Agriculture and Veterinary Services, University of Nairobi, P. O Box 29053, Nairobi, Kenya. Request for reprints to: Dr. J. N. Ombui, Department of Public Health, ..... Hall, B., Greene, R., Potter, M. E. Cohen, M. L. and Brake, B. A.. Chloramphenicol-resistant Salmonella newport traced through.

  5. Antimicrobial resistance and characterisation of staphylococci isolated from healthy Labrador retrievers in the United Kingdom.

    Science.gov (United States)

    Schmidt, Vanessa M; Williams, Nicola J; Pinchbeck, Gina; Corless, Caroline E; Shaw, Stephen; McEwan, Neil; Dawson, Susan; Nuttall, Tim

    2014-01-14

    Coagulase-positive (CoPS) and coagulase-negative (CoNS) staphylococci are normal commensals of the skin and mucosa, but are also opportunist pathogens. Meticillin-resistant (MR) and multidrug-resistant (MDR) isolates are increasing in human and veterinary healthcare. Healthy humans and other animals harbour a variety of staphylococci, including MR-CoPS and MR-CoNS. The main aims of the study were to characterise the population and antimicrobial resistance profiles of staphylococci from healthy non-vet visiting and non-antimicrobial treated Labrador retrievers in the UK. Nasal and perineal samples were collected from 73 Labrador retrievers; staphylococci isolated and identified using phenotypic and biochemical methods. They were also confirmed by matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF-MS), PCR of the nuc gene and PCR and sequencing of the tuf gene. Disc diffusion and minimum inhibitory concentration (MIC) susceptibility tests were determined for a range of antimicrobials. In total, 102 CoPS (S. pseudintermedius n = 91, S. aureus n = 11) and 334 CoNS isolates were detected from 99% of dogs in this study. In 52% of dogs CoNS only were detected, with both CoNS and CoPS detected in 43% dogs and CoPS only detected in 4% of dogs. Antimicrobial resistance was not common among CoPS, but at least one MDR-CoNS isolate was detected in 34% of dogs. MR-CoNS were detected from 42% of dogs but no MR-CoPS were isolated. S. epidermidis (52% of dogs) was the most common CoNS found followed by S. warneri (30%) and S. equorum (27%), with another 15 CoNS species isolated from ≤ 15% of dogs. S. pseudintermedius and S. aureus were detected in 44% and 8% of dogs respectively. MR- and MDR-CoPS were rare. However a high prevalence of MR- and MDR-CoNS were found in these dogs, even though they had no prior antimicrobial treatment or admission to veterinary premises. These findings are of concern due to the potential for opportunistic

  6. Addressing Antimicrobial Resistance: An Overview of Priority Actions to Prevent Suboptimal Antimicrobial Use in Food-Animal Production.

    Science.gov (United States)

    Lhermie, Guillaume; Gröhn, Yrjö T; Raboisson, Didier

    2016-01-01

    The growing concern regarding emergence of bacteria resistant to antimicrobials and their potential for transmission to humans via animal production has led various authorities worldwide to implement measures to decrease antimicrobial use (AMU) in livestock production. These measures are influenced by those implemented in human medicine, and emphasize the importance of antimicrobial stewardship, surveillance, infection prevention and control and research. In food producing animals, unlike human medicine, antimicrobials are used to control diseases which cause economic losses. This major difference may explain the failure of the public policies implemented to control antimicrobial usage. Here we first review the specific factors influencing AMU across the farm animal sector and highlighting the farmers' decision-making process of AMU. We then discuss the efficiency of existing regulations implemented by policy makers, and assess the need for alternative strategies, such as substitution between antimicrobials and other measures for infectious disease control. We also discuss the interests of regulating antimicrobial prices. Finally, we emphasize the value of optimizing antimicrobial regimens, and developing veterinary precision medicine to achieve clinical efficacy in animals while limiting negative impacts on public health. The fight against antimicrobial resistance requires both a reduction and an optimization of antimicrobial consumption. The set of actions currently implemented by policy makers does not adequately address the economic interests of farmers' use of antimicrobials.

  7. Population structure of Japanese extraintestinal pathogenic Escherichia coli and its relationship with antimicrobial resistance.

    Science.gov (United States)

    Matsumura, Yasufumi; Noguchi, Taro; Tanaka, Michio; Kanahashi, Toru; Yamamoto, Masaki; Nagao, Miki; Takakura, Shunji; Ichiyama, Satoshi

    2017-04-01

    To define the population structure of extraintestinal pathogenic Escherichia coli (ExPEC) in Japan and its relationship with antimicrobial resistance and the major resistance mechanisms for fluoroquinolones and β-lactams, we designed a multicentre prospective study. A total of 329 ExPEC isolates were collected at 10 Japanese acute-care hospitals during December 2014. We defined the clonal groups of ExPEC by fumC and fimH sequencing (CH typing). Antimicrobial susceptibility testing of 18 agents and the detection of mutations in quinolone resistance-determining regions (QRDRs) and β-lactamases were performed. Among the study isolates, 103 CH types were found, and CH40-30 (25%) and another 10 CH types (35% in total) constituted the major ExPEC population. Ciprofloxacin non-susceptibility, ESBLs and MDR phenotypes were found in 34%, 22% and 33%, respectively. CH40-30, corresponding to the C/H30 clade of the global pandemic ST131 clone, was associated with four QRDR mutations (100%) and bla CTX-M (60%) and was the most frequent type in 15 antimicrobial-non-susceptible populations (dominating 39%-75% of each population, the highest prevalence for ciprofloxacin), the ESBL producers (70%) and the MDR isolates (59%). Isolates that were non-susceptible to nalidixic acid and low-level resistant to ciprofloxacin with one or two QRDR mutations represented 16% of the study isolates and were distributed among the eight major and non-major CH types. More than half of the ExPEC population in Japan consisted of 11 major clones. Of these clones, the CH40-30-ST131-C/H30 clone was the predominant antimicrobial-resistant population. The presence of major clones with low-level ciprofloxacin resistance supports the potential future success of a non-ST131 fluoroquinolone-resistant clone. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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

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    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

  9. Antimicrobial-resistant bacteria in wild game in Slovenia

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    Križman, M.; Kirbiš, A.; Jamnikar-Ciglenečki, U.

    2017-09-01

    Wildlife is usually not exposed to clinically-used antimicrobial agents but can acquire antimicrobial resistance throughout contact with humans, domesticated animals and environments. Samples of faeces from intestines (80 in total) were collected from roe deer (52), wild boars (11), chamois (10) red deer (6) and moufflon (1). After culture on ChromID extended spectrum β-lactamase (ESBL) plates to select for growth of ESBL-producing bacteria, 25 samples produced bacterial colonies for further study. Six species of bacteria were identified from the 25 samples: Stenotrophomonas maltophilia, Serratia fonticola, Stenotrophomonas nitritireducens, Enterococcus faecium, Enterococcus faecalis and Escherichia coli. Two ESBL enzymes were amplified from group TEM and three from group CTX-M-1. Undercooked game meat and salami can be a source of resistant bacteria when animals are not eviscerated properly.

  10. Antimicrobial resistance in humans, livestock and the wider environment.

    Science.gov (United States)

    Woolhouse, Mark; Ward, Melissa; van Bunnik, Bram; Farrar, Jeremy

    2015-06-05

    Antimicrobial resistance (AMR) in humans is inter-linked with AMR in other populations, especially farm animals, and in the wider environment. The relatively few bacterial species that cause disease in humans, and are the targets of antibiotic treatment, constitute a tiny subset of the overall diversity of bacteria that includes the gut microbiota and vast numbers in the soil. However, resistance can pass between these different populations; and homologous resistance genes have been found in pathogens, normal flora and soil bacteria. Farm animals are an important component of this complex system: they are exposed to enormous quantities of antibiotics (despite attempts at reduction) and act as another reservoir of resistance genes. Whole genome sequencing is revealing and beginning to quantify the two-way traffic of AMR bacteria between the farm and the clinic. Surveillance of bacterial disease, drug usage and resistance in livestock is still relatively poor, though improving, but achieving better antimicrobial stewardship on the farm is challenging: antibiotics are an integral part of industrial agriculture and there are very few alternatives. Human production and use of antibiotics either on the farm or in the clinic is but a recent addition to the natural and ancient process of antibiotic production and resistance evolution that occurs on a global scale in the soil. Viewed in this way, AMR is somewhat analogous to climate change, and that suggests that an intergovernmental panel, akin to the Intergovernmental Panel on Climate Change, could be an appropriate vehicle to actively address the problem.

  11. Clostridium difficile Infection and Patient-Specific Antimicrobial Resistance Testing Reveals a High Metronidazole Resistance Rate.

    Science.gov (United States)

    Barkin, Jodie A; Sussman, Daniel A; Fifadara, Nimita; Barkin, Jamie S

    2017-04-01

    Clostridium difficile (CD) infection (CDI) causes marked morbidity and mortality, accounting for large healthcare expenditures annually. Current CDI treatment guidelines focus on clinical markers of patient severity to determine the preferred antibiotic regimen of metronidazole versus vancomycin. The antimicrobial resistance patterns for patients with CD are currently unknown. The aim of this study was to define the antimicrobial resistance patterns for CD. This study included all patients with stools sent for CD testing to a private laboratory (DRG Laboratory, Alpharetta, Georgia) in a 6-month period from across the USA. Patient data was de-identified, with only age, gender, and zip-code available per laboratory protocol. All samples underwent PCR testing followed by hybridization for CD toxin regions A and B. Only patients with CD-positive PCR were analyzed. Antimicrobial resistance testing using stool genomic DNA evaluated presence of imidazole- and vancomycin-resistant genes using multiplex PCR gene detection. Of 2743, 288 (10.5%) stool samples were positive for CD. Six were excluded per protocol. Of 282, 193 (69.4%) were women, and average age was 49.4 ± 18.7 years. Of 282, 62 were PCR positive for toxins A and B, 160 for toxin A positive alone, and 60 for toxin B positive alone. Antimicrobial resistance testing revealed 134/282 (47.5%) patients resistant to imidazole, 17 (6.1%) resistant to vancomycin, and 9 (3.2%) resistant to imidazole and vancomycin. CD-positive patients with presence of imidazole-resistant genes from stool DNA extract was a common phenomenon, while vancomycin resistance was uncommon. Similar to treatment of other infections, antimicrobial resistance testing should play a role in CDI clinical decision-making algorithms to enable more expedited and cost-effective delivery of patient care.

  12. Antimicrobial Resistance Risks of Cholera Prophylaxis for United Nations Peacekeepers

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    Kunkel, Amber; Lewnard, Joseph A.; Pitzer, Virginia E.; Cohen, Ted

    2017-01-01

    More than 5 years after a United Nations peacekeeping battalion introduced cholera to Haiti, over 150,000 peacekeepers continue to be deployed annually from countries where cholera is endemic. The United Nations has thus far declined to provide antimicrobial chemoprophylaxis to peacekeepers, a policy based largely on concerns that the risks of drug resistance generation and spread would outweigh the potential benefits of preventing future cholera importations. In this study, we sought to bett...

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

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    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.

  14. Concerning Increase in Antimicrobial Resistance in Shiga Toxin-Producing Escherichia coli Isolated from Young Animals during 1980-2016.

    Science.gov (United States)

    Chirila, Flore; Tabaran, Alexandra; Fit, Nicodim; Nadas, George; Mihaiu, Marian; Tabaran, Flaviu; Cătoi, Cornel; Reget, Oana Lucia; Dan, Sorin Daniel

    2017-09-27

    This study was conducted in order to assess the antimicrobial resistance patterns of E. coli isolated from young animals affected between 1980 and 2016. The selected isolates for this study (n=175) carried stx 1 /stx 2 genes and the most prevalent type of pathogenic E. coli found belonged to serogroup O101, antigen (K99)-F41 positive. All STEC-positive isolates were tested for susceptibility to 11 antimicrobials. Multidrug resistance (MDR) increased from 11% during the 1980s to 40% between 2000 and 2016. Resistance to tetracycline and streptomycin was the most frequent co-resistance phenotype (37%). Co-resistance to tetracycline and sulfonamide was found in 21% of E. coli isolates, while the MDR pattern to tetracycline, sulfonamide, and streptomycin was observed in 12% of the strains tested. Only 8% of isolates were co-resistant to tetracycline, ampicillin, streptomycin, and sulfonamide. The most common resistance genes found were those encoding for tetracycline, sulphonamides, and streptomycin, with 54% (n=95) of the tested isolates containing at least one of the genes encoding tetracycline resistance. A total of 87% of E. coli that tested positive for tetracycline (tetA, tetB, and tetC) and sulphonamide (sul1) resistance genes were isolated between 2000 and 2016. A large number of isolates (n=21) carried int1 and a nucleotide sequence analysis revealed that all class 1 integron gene cassettes carried sul1, tet, and dfrA1 resistance genes. An increase was observed in the level of resistance to antimicrobials in Romania, highlighting the urgent need for a surveillance and prevention system for antimicrobial resistance in livestock in Eastern Europe.

  15. Correlation between antimicrobial consumption and antimicrobial resistance of Pseudomonas aeruginosa in a hospital setting: a 10-year study.

    Science.gov (United States)

    Mladenovic-Antic, S; Kocic, B; Velickovic-Radovanovic, R; Dinic, M; Petrovic, J; Randjelovic, G; Mitic, R

    2016-10-01

    Antimicrobial resistance is one of the greatest threats to human health. One of the most important factors leading to the emergence of resistant bacteria is overuse of antibiotics. The purpose of this study was to investigate the correlation between antimicrobial usage and bacterial resistance of Pseudomonas aeruginosa (P. aeruginosa) over a 10-year period in the Clinical Center Niš, one of the biggest tertiary care hospitals in Serbia. We focused on possible relationships between the consumption of carbapenems and beta-lactam antibiotics and the rates of resistance of P. aeruginosa to carbapenems. We recorded utilization of antibiotics expressed as defined daily doses per 100 bed days (DBD). Bacterial resistance was reported as the percentage of resistant isolates (percentage of all resistant and intermediate resistant strains) among all tested isolates. A significant increasing trend in resistance was seen in imipenem (P resistance to amikacin (P resistance to imipenem in P. aeruginosa shows significance (P resistance to meropenem showed a trend towards significance (P > 0·05, Pearson r = 0·607). We found a very good correlation between the use of all beta-lactam and P. aeruginosa resistance to carbapenems (P antimicrobial resistance to carbapenems, significant correlations between the consumption of antibiotics, especially carbapenems and beta-lactams, and rates of antimicrobial resistance of P. aeruginosa to imipenem and meropenem. © 2016 John Wiley & Sons Ltd.

  16. Troglitazone reverses the multiple drug resistance phenotype in cancer cells

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    Gerald F Davies

    2009-03-01

    Full Text Available Gerald F Davies1, Bernhard HJ Juurlink2, Troy AA Harkness11Department of Anatomy and Cell Biology, College of Medicine, University of Saskatchewan, Saskatoon, Canada; 2College of Medicine, Alfaisal University, Riyadh, Kingdom of Saudi ArabiaAbstract: A major problem in treating cancer is the development of drug resistance. We previously demonstrated doxorubicin (DOX resistance in K562 human leukemia cells that was associated with upregulation of glyoxalase 1 (GLO-1 and histone H3 expression. The thiazolidinedione troglitazone (TRG downregulated GLO-1 expression and further upregulated histone H3 expression and post-translational modifications in these cells, leading to a regained sensitivity to DOX. Given the pleiotropic effects of epigenetic changes in cancer development, we hypothesized that TRG may downregulate the multiple drug resistance (MDR phenotype in a variety of cancer cells. To test this, MCF7 human breast cancer cells and K562 cells were cultured in the presence of low-dose DOX to establish DOX-resistant cell lines (K562/DOX and MCF7/DOX. The MDR phenotype was confirmed by Western blot analysis of the 170 kDa P-glycoprotein (Pgp drug efflux pump multiple drug resistance protein 1 (MDR-1, and the breast cancer resistance protein (BCRP. TRG markedly decreased expression of both MDR-1 and BCRP in these cells, resulting in sensitivity to DOX. Silencing of MDR-1 expression also sensitized MCF7/DOX cells to DOX. Use of the specific and irreversible peroxisome proliferator-activated receptor gamma (PPARγ inhibitor GW9662 in the nanomolar range not only demonstrated that the action of TRG on MCF/DOX was PPARγ-independent, but indicated that PPARγ may play a role in the MDR phenotype, which is antagonized by TRG. We conclude that TRG is potentially a useful adjunct therapy in chemoresistant cancers. Keywords: chemotherapy, doxorubicin, breast cancer resistance protein-1, multiple drug resistance, multiple drug resistance protein 1

  17. Control of Antimicrobial Resistance Requires an Ethical Approach

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    Ben Parsonage

    2017-11-01

    Full Text Available Ethical behavior encompasses actions that benefit both self and society. This means that tackling antimicrobial resistance (AMR becomes an ethical obligation, because the prospect of declining anti-infectives affects everyone. Without preventive action, loss of drugs that have saved lives over the past century, will condemn ourselves, people we know, and people we don’t know, to unacceptable risk of untreatable infection. Policies aimed at extending antimicrobial life should be considered within an ethical framework, in order to balance the choice, range, and quality of drugs against stewardship activities. Conserving availability and effectiveness for future use should not compromise today’s patients. Practices such as antimicrobial prophylaxis for healthy people ‘at risk’ should receive full debate. There are additional ethical considerations for AMR involving veterinary care, agriculture, and relevant bio-industries. Restrictions for farmers potentially threaten the quality and quantity of food production with economic consequences. Antibiotics for companion animals do not necessarily spare those used for humans. While low-income countries cannot afford much-needed drugs, pharmaceutical companies are reluctant to develop novel agents for short-term return only. Public demand encourages over-the-counter, internet, black market, and counterfeit drugs, all of which compromise international control. Prescribers themselves require educational support to balance therapeutic choice against collateral damage to both body and environment. Predicted mortality due to AMR provides justification for international co-operation, commitment and investment to support surveillance and stewardship along with development of novel antimicrobial drugs. Ethical arguments for, and against, control of antimicrobial resistance strategies are presented and discussed in this review.

  18. Phenotypic Assays to Determine Virulence Factors of Uropathogenic Escherichia coli (UPEC) Isolates and their Correlation with Antibiotic Resistance Pattern.

    Science.gov (United States)

    Tabasi, Mohsen; Asadi Karam, Mohammad Reza; Habibi, Mehri; Yekaninejad, Mir Saeed; Bouzari, Saeid

    2015-08-01

    Urinary tract infection caused by uropathogenic Escherichia coli (UPEC) strains is one of the most important infections in the world. UPEC encode widespread virulence factors closely related with pathogenesis of the bacteria. The purpose of this study was to evaluate the presence of different phenotypic virulence markers in UPEC isolates and determine their correlation with antibiotic resistance pattern. UPEC isolates from patients with different clinical symptoms of UTI were collected and screened for biofilm and hemolysin production, mannose resistant, and mannose sensitive hemagglutination (MRHA and MSHA, respectively). In addition, antimicrobial resistance pattern and ESBL-producing isolates were recorded. Of the 156 UPEC isolates, biofilm and hemolysin formation was seen in 133 (85.3%) and 53 (34%) isolates, respectively. Moreover, 98 (62.8%) and 58 (37.2%) isolates showed the presence of Types 1 fimbriae (MSHA) and P fimbriae (MRHA), respectively. Our results also showed a relationship between biofilm formation in UPEC isolated from acute cystitis patients and recurrent UTI cases. Occurrence of UTI was dramatically correlated with the patients' profiles. We observed that the difference in antimicrobial susceptibilities of the biofilm and nonbiofilm former isolates was statistically significant. The UPEC isolates showed the highest resistance to ampicillin, tetracycline, amoxicillin, and cotrimoxazole. Moreover, 26.9% of isolates were ESBL producers. This study indicated that there is a relationship between the phenotypic virulence traits of the UPEC isolates, patients' profiles, and antibiotic resistance. Detection of the phenotypic virulence factors could help to improve understanding of pathogenesis of UPEC isolates and better medical intervention.

  19. 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

  20. 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

    2016-11-07

    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

  1. Enterotoxigenicity and Antimicrobial Resistance of Staphylococcus aureus Isolated from Retail Food in China

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    Wei Wang

    2017-11-01

    Full Text Available Staphylococcus aureus is one of the most common causes of zoonotic agent in the world, which are attributable to the contamination of food with enterotoxins. In this study, a total of 1,150 S. aureus isolates were cultured from 27,000 retail foods items from 203 cities of 24 provinces in China in 2015 and were test for antimicrobial susceptibility. Additionally, the role of the genes responsible for the staphylococcal enterotoxins (SEA to SEE, methicillin resistance (mecA and the toxigenic capabilities were also assessed. The results showed that 4.3% retail foods were contaminated with S. aureus, and 7.9% retail foods isolates were mecA positive. Some 97.6% of S. aureus isolates were resistant to at least one antimicrobial compound, and 57.5% of these were multi drug resistant (MDR. Resistance to penicillin (83.7%, 963/1,150, was common, followed by linezolid (67.7%, 778/1,150 and erythromycin (52.1%, 599/1,150. The isolates cultured from raw meats showed high levels of resistant to tetracycline (42.8%, ciprofloxacin (17.4%, and chloramphenicol (12.0% and expressed a MDR phenotype (62.4%. A total of 29.7% S. aureus isolates harbored the classical SEs genes (sea, seb, sec, and sed. The sea and seb genes were the most frequent SEs genes detected. Of note, 22% of the SEs genes positive S. aureus harbored two or three SEs genes, and 16 isolates were confirmed with the capacity to simultaneously produce two or three enterotoxin types. Moreover, nearly 50% of the MRSA isolates were positive for at least one SE gene in this study. Therefore, it is important to monitor the antimicrobial susceptibility and enterotoxigenicity of MDR S. aureus and MRSA in the food chain and to use these data to develop food safety measures, designed to reduce the contamination and transmission of this bacterium.

  2. Potential Sources and Transmission of Salmonella and Antimicrobial Resistance in Kampala, Uganda.

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    Josephine A Afema

    Full Text Available In sub‒Saharan Africa, non‒typhoidal Salmonellae (NTS cause invasive disease particularly in children and HIV infected adults, but the disease epidemiology is poorly understood. Between 2012 and 2013, we investigated NTS sources and transmission in Kampala. We detected Salmonella in 60% of the influent and 60% of the effluent samples from a wastewater treatment plant and 53.3% of the influent and 10% of the effluent samples from waste stabilization ponds that serve the human population; 40.9% of flush‒water samples from ruminant slaughterhouses, 6.6% of the poultry fecal samples from live bird markets and 4% of the fecal samples from swine at slaughter; and in 54.2% of the water samples from a channel that drains storm-water and effluents from the city. We obtained 775 Salmonella isolates, identified 32 serovars, and determined resistance to 15 antimicrobials. We genotyped common serovars using multiple‒locus variable number tandem repeats analysis or pulsed‒field gel electrophoresis. In addition, we analyzed 49 archived NTS isolates from asymptomatic livestock and human clinical cases. Salmonella from ruminant and swine sources were mostly pan‒susceptible (95% while poultry isolates were generally more resistant. Salmonella Kentucky isolated from poultry exhibited extensive drug resistance characterized by resistance to 10 antimicrobials. Interestingly, similar genotypes of S. Kentucky but with less antimicrobial resistance (AMR were found in poultry, human and environmental sources. The observed AMR patterns could be attributed to host or management factors associated with production. Alternatively, S. Kentucky may be prone to acquiring AMR. The factors driving AMR remain poorly understood and should be elucidated. Overall, shared genotypes and AMR phenotypes were found in NTS from human, livestock and environmental sources, suggesting zoonotic and environmental transmissions most likely occur. Information from this study could be

  3. Enterotoxigenicity and Antimicrobial Resistance of Staphylococcus aureus Isolated from Retail Food in China

    Science.gov (United States)

    Wang, Wei; Baloch, Zulqarnain; Jiang, Tao; Zhang, Cunshan; Peng, Zixin; Li, Fengqin; Fanning, Séamus; Ma, Aiguo; Xu, Jin

    2017-01-01

    Staphylococcus aureus is one of the most common causes of zoonotic agent in the world, which are attributable to the contamination of food with enterotoxins. In this study, a total of 1,150 S. aureus isolates were cultured from 27,000 retail foods items from 203 cities of 24 provinces in China in 2015 and were test for antimicrobial susceptibility. Additionally, the role of the genes responsible for the staphylococcal enterotoxins (SEA to SEE), methicillin resistance (mecA) and the toxigenic capabilities were also assessed. The results showed that 4.3% retail foods were contaminated with S. aureus, and 7.9% retail foods isolates were mecA positive. Some 97.6% of S. aureus isolates were resistant to at least one antimicrobial compound, and 57.5% of these were multi drug resistant (MDR). Resistance to penicillin (83.7%, 963/1,150), was common, followed by linezolid (67.7%, 778/1,150) and erythromycin (52.1%, 599/1,150). The isolates cultured from raw meats showed high levels of resistant to tetracycline (42.8%), ciprofloxacin (17.4%), and chloramphenicol (12.0%) and expressed a MDR phenotype (62.4%). A total of 29.7% S. aureus isolates harbored the classical SEs genes (sea, seb, sec, and sed). The sea and seb genes were the most frequent SEs genes detected. Of note, 22% of the SEs genes positive S. aureus harbored two or three SEs genes, and 16 isolates were confirmed with the capacity to simultaneously produce two or three enterotoxin types. Moreover, nearly 50% of the MRSA isolates were positive for at least one SE gene in this study. Therefore, it is important to monitor the antimicrobial susceptibility and enterotoxigenicity of MDR S. aureus and MRSA in the food chain and to use these data to develop food safety measures, designed to reduce the contamination and transmission of this bacterium. PMID:29209290

  4. 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

  5. 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.

  6. [Susceptibility and resistence of Pseudomonas aeruginosa to antimicrobial agents].

    Science.gov (United States)

    Gamero Delgado, M C; García-Mayorgas, A D; Rodríguez, F; Ibarra, A; Casal, M

    2007-06-01

    Pseudomonas aeruginosa is an opportunistic microorganism that is frequently the cause of nosocomial infections. Multiple mechanisms are involved in its natural and acquired resistance to many of the antimicrobial agents commonly used in clinical practice. The objective of this study was to assess the susceptibility and resistance patterns of P. aeruginosa strains isolated in Hospital Reina Sofia between 2000 and 2005, as well as to analyze the differences between intrahospital and extrahospital isolates in 2005 and to compare the results with those obtained in other studies. A total of 3,019 strains of P. aeruginosa from different hospitals and nonhospital settings were evaluated, taking into consideration their degree of sensitivity to different antibiotics. The MICs were determined by means of the Wider I automated system (Soria Melguizo), taking into consideration the criteria of susceptibility and resistance recommended by MENSURA. Results of the analysis showed that P. aeruginosa maintained similar levels of antimicrobial susceptibility during the period 2000-2005, with increased susceptibility to amikacin, gentamicin and tobramycin. There were also important differences in the degree of susceptibility between intrahospital and extrahospital strains, except for imipenem and fosfomycin. The intrahospital difference in susceptibility was also evaluated, emphasizing the importance of periodically studying susceptibility and resistance patterns of P. aeruginosa in each setting in order to evaluate different therapeutic guidelines, as it is not always advisable to extrapolate data from different regions. These differences can be explained by the different use of antibiotics in each center and the geographic variations of the resistance mechanisms of P. aeruginosa.

  7. Association between antimicrobial resistance and virulence in Escherichia coli.

    Science.gov (United States)

    Da Silva, Gabriela Jorge; Mendonça, Nuno

    2012-01-01

    Escherichia coli represents a major cause of morbidity and mortality worldwide. The treatment of E. coli infections is now threatened by the emergence of antimicrobial resistance. The dissemination of resistance is associated with genetic mobile elements, such as plasmids, that may also carry virulence determinants. A proficient pathogen should be virulent, resistant to antibiotics, and epidemic. However, the interplay between resistance and virulence is poorly understood. This review aims to critically discuss the association and linked transmission of both resistance and virulence traits in strains from extraintestinal infections in E. coli, and intestinal pathotypes. Despite the numerous controversies on this topic, findings from research published to date indicate that there is a link between resistance and virulence, as illustrated by the successful E. coli ST131 epidemic clone. Perhaps the most commonly accepted view is that resistance to quinolones is linked to a loss of virulence factors. However, the low virulent phylogenetic groups might be more prone to acquire resistance to quinolones. Specific characteristics of the E. coli genome that have yet to be identified may contribute to such genetic linkages. Research based on bacterial populations is sorely needed to help understand the molecular mechanisms underlying the association between resistance and virulence, that, in turn, may help manage the future disseminations of infectious diseases in their entirety.

  8. [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.

  9. Antibiotic resistance genes and residual antimicrobials in cattle feedlot surface soil

    Science.gov (United States)

    Antibiotic residues and resistant bacteria in cattle feedlot manure may impact antibiotic resistance in the environment. This study investigated common antimicrobials (tetracyclines and monensin) and associated resistance genes in cattle feedlot soils over time. Animal diets and other feedlot soil...

  10. Proper context: Comparison studies demonstrate that United States food-animal production antimicrobial uses have minimal impact on antimicrobial resistance

    Science.gov (United States)

    In the United States (US) it is estimated that food-animal production agriculture accounts for >70% of antimicrobial (AM) use leading to concerns that agricultural uses "substantially drive" antimicrobial resistance (AMR). Many studies report AMR in food-animal production settings without comparison...

  11. 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.

  12. Quantitative assessment of antimicrobial resistance in livestock during the course of a Nationwide antimicrobial use reduction in the Nethterlands

    NARCIS (Netherlands)

    Dorado-García, Alejandro; Mevius, D.J.; Jacobs, José J.H.; Geijlswijk, van I.M.; Mouton, J.W.; Wagenaar, J.A.; Heederik, Dick

    2016-01-01

    Objectives To quantify associations between antimicrobial use and acquired resistance in indicator Escherichia coli over a period of time which involved sector-wide antimicrobial use reductions in broilers and pigs (years 2004–14), veal calves (2007–14) and dairy cattle (2005–14). Prevalence

  13. Quantitative assessment of antimicrobial resistance in livestock during the course of a nationwide antimicrobial use reduction in the Netherlands.

    NARCIS (Netherlands)

    Dorado-García, Alejandro|info:eu-repo/dai/nl/372621023; Mevius, Dik J|info:eu-repo/dai/nl/079677347; Jacobs, José J H|info:eu-repo/dai/nl/314101144; Van Geijlswijk, Inge M|info:eu-repo/dai/nl/413489477; Mouton, Johan W; Wagenaar, Jaap A|info:eu-repo/dai/nl/126613354; Heederik, Dick J|info:eu-repo/dai/nl/072910542

    2016-01-01

    OBJECTIVES To quantify associations between antimicrobial use and acquired resistance in indicator Escherichia coli over a period of time which involved sector-wide antimicrobial use reductions in broilers and pigs (years 2004-14), veal calves (2007-14) and dairy cattle (2005-14). Prevalence

  14. Phenotypic and genotypic characterization of antimicrobial susceptibility of avian pathogenicEscherichia coliisolated from broiler chickens.

    Science.gov (United States)

    Younis, Gamal; Awad, Amal; Mohamed, Nada

    2017-10-01

    Avian pathogenic Escherichia coli (APEC) is pathogenic strains of E. coli that are responsible for one of the most common bacterial diseases affecting poultry worldwide. This study was designed to determine the occurrence, antibiotic resistance profile, and antibiotic resistance genes of E. coli isolated from diseased and freshly dead broilers. In that context, a total of 200 broilers samples were examined by standard microbiological techniques for isolation of E. coli , and tested for their antimicrobial susceptibility against 15 antimicrobial agents using disc diffusion method. In addition, E. coli isolates were screened by multiplex polymerase chain reaction for detection of a number of resistance genes including aadA1 gene encodes streptomycin/neomycin, tetA encodes resistance to tetracycline, sul1 encodes sulfonamides, and β-lactamase encoding genes (bla TEM and bla SHV ). A total of 73 (36.5%) isolates were biochemically identified as E. coli strains. O78, O2, and O1 are the most prevalent serotypes detected. E. coli displayed a high resistance against penicillin (100%), followed by cefepime (95.8%) and a low resistance to norfloxacin (36.9%), and chloramphenicol (30%). Depending on the results of PCR, sul 1 gene was the most predominant antibiotic resistant gene (87%) followed by bla TEM (78%), tetA genes (60%), and aadA (54%). However, bla SHV had the lowest prevalence (23%). The obtained results demonstrated the importance of studies on APEC and antibiotic resistance genes in our region which associated with intensive poultry industry, aiming to acquire preventive measures to minimize losses due to APEC and associated multidrug-resistance and resistance genes that of high significance to the rational use of antibiotics in clinical and public health.

  15. Phenotypic and genotypic characterization of antimicrobial susceptibility of avian pathogenic Escherichia coli isolated from broiler chickens

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    Gamal Younis

    2017-10-01

    Full Text Available Aim: Avian pathogenic Escherichia coli (APEC is pathogenic strains of E. coli that are responsible for one of the most common bacterial diseases affecting poultry worldwide. This study was designed to determine the occurrence, antibiotic resistance profile, and antibiotic resistance genes of E. coli isolated from diseased and freshly dead broilers. Materials and Methods: In that context, a total of 200 broilers samples were examined by standard microbiological techniques for isolation of E. coli, and tested for their antimicrobial susceptibility against 15 antimicrobial agents using disc diffusion method. In addition, E. coli isolates were screened by multiplex polymerase chain reaction for detection of a number of resistance genes including aadA1 gene encodes streptomycin/neomycin, tetA encodes resistance to tetracycline, sul1 encodes sulfonamides, and β-lactamase encoding genes (blaTEM and blaSHV. Results: A total of 73 (36.5% isolates were biochemically identified as E. coli strains. O78, O2, and O1 are the most prevalent serotypes detected. E. coli displayed a high resistance against penicillin (100%, followed by cefepime (95.8% and a low resistance to norfloxacin (36.9%, and chloramphenicol (30%. Depending on the results of PCR, sul1 gene was the most predominant antibiotic resistant gene (87% followed by blaTEM (78%, tetA genes (60%, and aadA (54%. However, blaSHV had the lowest prevalence (23%. Conclusion: The obtained results demonstrated the importance of studies on APEC and antibiotic resistance genes in our region which associated with intensive poultry industry, aiming to acquire preventive measures to minimize losses due to APEC and associated multidrug-resistance and resistance genes that of high significance to the rational use of antibiotics in clinical and public health.

  16. Perceptions of antimicrobial usage, antimicrobial resistance and policy measures to reduce antimicrobial usage in convenient samples of Belgian, French, German, Swedish and Swiss pig farmers.

    Science.gov (United States)

    Visschers, V H M; Backhans, A; Collineau, L; Iten, D; Loesken, S; Postma, M; Belloc, C; Dewulf, J; Emanuelson, U; Beilage, E Grosse; Siegrist, M; Sjölund, M; Stärk, K D C

    2015-04-01

    We conducted a survey among convenient samples of pig farmers (N=281) in Belgium, France, Germany, Sweden and Switzerland. We identified some significant differences among the five investigated countries (independent variable) regarding farmers' antimicrobial usage compared to their own country and worries related to pig farming (dependent variables), but most of the differences were rather small. In general, farmers perceived their own antimicrobial usage to be lower than that of their peers in the same country and lower than or similar to that of farmers from other countries. This may be a consequence of our convenience sample, resulting in self-selection of highly motivated farmers. Farmers were significantly more worried about financial/legal issues than about antimicrobial resistance. They believed that a reduction in revenues for slaughter pigs treated with a large amount of antimicrobials would have the most impact on reduced antimicrobial usage in their country. Further, farmers who were more worried about antimicrobial resistance and who estimated their own antimicrobial usage as lower than their fellow countrymen, perceived more impact from policy measures on the reduction of antimicrobials. Our results indicated that the same policy measures can be applied to reduce antimicrobial usage in pig farming in all five countries. Moreover, it seems worthwhile to increase pig farmers' awareness of the threat of antimicrobial resistance and its relation to antimicrobial usage; not only because pig farmers appeared little worried about antimicrobial usage but also because it affected farmers' perception of policy measures to reduce antimicrobial usage. Our samples were not representative for the national pig farmer populations. Further research is therefore needed to examine to what extent our findings can be generalised to these populations and to farmers in other countries. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Antimicrobial resistance in Shiga toxin-producing Escherichia coli serogroups O157 and O26 isolated from human cases of diarrhoeal disease in England, 2015.

    Science.gov (United States)

    Day, Martin; Doumith, Michel; Jenkins, Claire; Dallman, Timothy J; Hopkins, Katie L; Elson, Richard; Godbole, Gauri; Woodford, Neil

    2017-01-01

    Shiga toxin-producing Escherichia coli (STEC) are zoonotic and transmission to humans occurs via contaminated food or contact with infected animals. In this study, WGS data were used to predict antimicrobial resistance (AMR) in STEC from symptomatic human cases to assess the extent of transmission of antibiotic-resistant E. coli from animals to humans. WGS data from 430 isolates of STEC were mapped to genes known to be associated with phenotypic AMR. Susceptibility testing was performed by a breakpoint method on all viable isolates exhibiting resistance to at least one antimicrobial. 327/396 (82.6%) of STEC O157 and 22/34 (64.7%) of STEC O26 lacked identifiable resistance genes and were predicted to be fully susceptible to 11 diverse classes of antimicrobials. For the remaining 81 isolates, 74 were phenotypically tested and there was concordance between WGS-predicted resistance and expression of phenotypic resistance. The most common resistance profile was ampicillin, streptomycin, trimethoprim/sulphonamide and tetracycline occurring in 25 (5.8%) isolates. Resistance to other antimicrobials, including resistance to chloramphenicol (2.1%), resistance to azithromycin (0.2%) and reduced susceptibility to ciprofloxacin (2.6%), was less frequent. Three isolates were identified as ESBL producers. β-Lactams, trimethoprim/sulphonamides and tetracyclines account for the majority of therapeutic antimicrobials sold for veterinary use and this may be a risk factor for the presence of AMR in domestically acquired human clinical isolates of STEC. Isolates that were resistant to ampicillin, streptomycin, sulphonamide, tetracycline and azithromycin and had reduced susceptibility to ciprofloxacin were associated with cases who reported recent travel abroad. © Crown copyright 2016.

  18. Beta-lactamase antimicrobial resistance in Klebsiella and Enterobacter species isolated from healthy and diarrheic dogs in Andhra Pradesh, India

    Directory of Open Access Journals (Sweden)

    N. Mohammad Sharif

    2017-08-01

    Full Text Available Aim: The aim of this study was to characterize beta-lactamase antimicrobial resistance in Klebsiella and Enterobacter species isolated from healthy and diarrheic dogs in Andhra Pradesh. Materials and Methods: A total of 136 rectal swabs were collected from healthy (92 and diarrheic (44 dogs, bacteriological cultured for Klebsiella and Enterobacter growth and screened for beta-lactamase antimicrobial resistance phenotypically by disc diffusion method and genotypically by polymerase chain reaction targeting blaTEM, blaSHV, blaOXA, blaCTX-M Group 1, 2, blaAmpC, blaACC, and blaMOX genes. Results: A total of 33 Klebsiella and 29 Enterobacter isolates were recovered. Phenotypic beta-lactamase resistance was detected in 66.6% and 25% of Klebsiella and Enterobacter isolates, respectively, from healthy dogs and 66.6% and 60% of Klebsiella and Enterobacter isolates, respectively, from diarrheic dogs. Overall, incidence of extended-spectrum beta-lactamase (ESBL phenotype was found to be 21.2% (7/33 in Klebsiella isolates, whereas none of the Enterobacter isolates exhibited ESBL phenotype. Predominant beta-lactamase genes detected in Klebsiella species include blaSHV (84.8%, followed by blaTEM (33.3%, blaCTX-M Group 1 (15.1%, and blaOXA (6.1% gene. Predominant beta-lactamase genes detected in Enterobacter species include blaSHV (48.2%, followed by blaTEM (24.1%, blaAmpC (13.7%, and blaOXA (10.3% gene. Conclusion: The present study highlighted alarming beta-lactamase resistance in Klebsiella and Enterobacter species of canine origin in India with due emphasis as indicators of antimicrobial resistance.

  19. Beta-lactamase antimicrobial resistance inKlebsiellaandEnterobacterspecies isolated from healthy and diarrheic dogs in Andhra Pradesh, India.

    Science.gov (United States)

    Sharif, N Mohammad; Sreedevi, B; Chaitanya, R K; Sreenivasulu, D

    2017-08-01

    The aim of this study was to characterize beta-lactamase antimicrobial resistance in Klebsiella and Enterobacter species isolated from healthy and diarrheic dogs in Andhra Pradesh. A total of 136 rectal swabs were collected from healthy (92) and diarrheic (44) dogs, bacteriological cultured for Klebsiella and Enterobacter growth and screened for beta-lactamase antimicrobial resistance phenotypically by disc diffusion method and genotypically by polymerase chain reaction targeting bla TEM , bla SHV , bla OXA , bla CTX-M Group 1, 2, bla AmpC , bla ACC , and bla MOX genes. A total of 33 Klebsiella and 29 Enterobacter isolates were recovered. Phenotypic beta-lactamase resistance was detected in 66.6% and 25% of Klebsiella and Enterobacter isolates, respectively, from healthy dogs and 66.6% and 60% of Klebsiella and Enterobacter isolates, respectively, from diarrheic dogs. Overall, incidence of extended-spectrum beta-lactamase (ESBL) phenotype was found to be 21.2% (7/33) in Klebsiella isolates, whereas none of the Enterobacter isolates exhibited ESBL phenotype. Predominant beta-lactamase genes detected in Klebsiella species include bla SHV (84.8%), followed by bla TEM (33.3%), bla CTX-M Group 1 (15.1%), and bla OXA (6.1%) gene. Predominant beta-lactamase genes detected in Enterobacter species include bla SHV (48.2%), followed by bla TEM (24.1%), bla AmpC (13.7%), and bla OXA (10.3%) gene. The present study highlighted alarming beta-lactamase resistance in Klebsiella and Enterobacter species of canine origin in India with due emphasis as indicators of antimicrobial resistance.

  20. Controlling Antimicrobial Resistance: Lessons from Scotland for India

    Directory of Open Access Journals (Sweden)

    Suchita Bhattacharyya

    2018-01-01

    Full Text Available Introduction In India, antimicrobial resistance (AMR is a serious public health problem. While some official policies have been formulated, they are not comprehensive and their enforcement is not monitored or regulated. This paper discusses the success achieved by the Scottish Antimicrobial Prescribing Group (SAPG and derives lessons relevant for AMR policies in India. Methods This study involved secondary data review and discussions with SAPG representatives. Results India is the largest consumer of antibiotics for human health (10.7 units/person and this consumption is steadily increasing. Irrational use, fixed‐dose combinations and growing antibiotic use in livestock have resulted in newer drug‐resistant pathogens. In 2008, the Scottish government initiated the SAPG that has achieved nationwide success in AMR control. The enormous success achieved by SAPG has demonstrated that this delivery model is effective in addressing AMR and can also be used in India, with country‐specific modifications. Conclusions In India, strong political and stakeholder support is required for a pragmatic one‐health approach to antimicrobial governance that would involve the interplay between agriculture, livestock and pharmaceutical industries. Project management, quality improvement, information management and performance assessment through accountability measures are essential. These can be coordinated nationally and implemented locally through existing structures and institutes. This needs to be supported by a powerful clinical network and underpinned by robust educational support that is dynamic to meet the needs of local healthcare professionals and general population.

  1. Antimicrobial resistance in Acinetobacter baumannii: From bench to bedside

    Science.gov (United States)

    Lin, Ming-Feng; Lan, Chung-Yu

    2014-01-01

    Acinetobacter baumannii (A. baumannii) is undoubtedly one of the most successful pathogens in the modern healthcare system. With invasive procedures, antibiotic use and immunocompromised hosts increasing in recent years, A. baumannii has become endemic in hospitals due to its versatile genetic machinery, which allows it to quickly evolve resistance factors, and to its remarkable ability to tolerate harsh environments. Infections and outbreaks caused by multidrug-resistant A. baumannii (MDRAB) are prevalent and have been reported worldwide over the past twenty or more years. To address this problem effectively, knowledge of species identification, typing methods, clinical manifestations, risk factors, and virulence factors is essential. The global epidemiology of MDRAB is monitored by persistent surveillance programs. Because few effective antibiotics are available, clinicians often face serious challenges when treating patients with MDRAB. Therefore, a deep understanding of the resistance mechanisms used by MDRAB can shed light on two possible strategies to combat the dissemination of antimicrobial resistance: stringent infection control and antibiotic treatments, of which colistin-based combination therapy is the mainstream strategy. However, due to the current unsatisfying therapeutic outcomes, there is a great need to develop and evaluate the efficacy of new antibiotics and to understand the role of other potential alternatives, such as antimicrobial peptides, in the treatment of MDRAB infections. PMID:25516853

  2. Antimicrobial drug resistance: "Prediction is very difficult, especially about the future".

    Science.gov (United States)

    Courvalin, Patrice

    2005-10-01

    Evolution of bacteria towards resistance to antimicrobial drugs, including multidrug resistance, is unavoidable because it represents a particular aspect of the general evolution of bacteria that is unstoppable. Therefore, the only means of dealing with this situation is to delay the emergence and subsequent dissemination of resistant bacteria or resistance genes. Resistance to antimicrobial drugs in bacteria can result from mutations in housekeeping structural or regulatory genes. Alternatively, resistance can result from the horizontal acquisition of foreign genetic information. The 2 phenomena are not mutually exclusive and can be associated in the emergence and more efficient spread of resistance. This review discusses the predictable future of the relationship between antimicrobial drugs and bacteria.

  3. High Prevalence of Antimicrobial-resistant Gram-negative Colonization in Hospitalized Cambodian Infants.

    Science.gov (United States)

    Turner, Paul; Pol, Sreymom; Soeng, Sona; Sar, Poda; Neou, Leakhena; Chea, Phal; Day, Nicholas Pj; Cooper, Ben S; Turner, Claudia

    2016-08-01

    Antimicrobial-resistant Gram-negative infections are a significant cause of mortality in young infants. We aimed to determine characteristics of, and risk factors for, colonization and invasive infection caused by 3rd generation cephalosporin (3GC) or carbapenem-resistant organisms in outborn infants admitted to a neonatal unit (NU) in Cambodia. During the first year of operation, patients admitted to the Angkor Hospital for Children NU, Siem Reap, Cambodia, underwent rectal swabbing on admission and twice weekly until discharge. Swabs were taken also from 7 environmental sites. Swabs were cultured to identify 3GC or carbapenem-resistant Acinetobacter sp., Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa. The study included 333 infants with a median age at NU admission of 10 days (range, 0-43). Colonization by ≥1 3GC-resistant organism was detected in 85.9% (286/333). Admission swabs were collected in 289 infants: 61.9% were colonized by a 3GC-resistant organism at the time of admission, and a further 23.2% were colonized during hospitalization, at a median of 4 days [95% confidence interval: 3-5]. Probiotic treatment (hazard ratio: 0.58; 95% confidence interval: 0.35-0.98) was associated with delayed colonization. Colonization by a carbapenem-resistant organism occurred in 25 (7.5%) infants. Six infants had NU-associated K. pneumoniae bacteremia; phenotypically identical colonizing strains were found in 3 infants. Environmental colonization occurred early. Colonization by antimicrobial-resistant Gram-negative organisms occurred early in hospitalized Cambodian infants and was associated with subsequent invasive infection. Trials of potential interventions such as probiotics are needed.

  4. Resistance to Antimicrobials Mediated by Efflux Pumps in Staphylococcus aureus

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    Isabel Couto

    2013-03-01

    Full Text Available Resistance mediated by efflux has been recognized in Staphylococcus aureus in the last few decades, although its clinical relevance has only been recognized recently. The existence of only a few studies on the individual and overall contribution of efflux to resistance phenotypes associated with the need of well-established methods to assess efflux activity in clinical isolates contributes greatly to the lack of solid knowledge of this mechanism in S. aureus. This study aims to provide information on approaches useful to the assessment and characterization of efflux activity, as well as contributing to our understanding of the role of efflux to phenotypes of antibiotic resistance and biocide tolerance in S. aureus clinical isolates. The results described show that efflux is an important contributor to fluoroquinolone resistance in S. aureus and suggest it as a major mechanism in the early stages of resistance development. We also show that efflux plays an important role on the reduced susceptibility to biocides in S. aureus, strengthening the importance of this long neglected resistance mechanism to the persistence and proliferation of antibiotic/biocide-resistant S. aureus in the hospital environment.

  5. Carbapenem-resistant and cephalosporin-susceptible: a worrisome phenotype among Pseudomonas aeruginosa clinical isolates in Brazil

    Directory of Open Access Journals (Sweden)

    Eloiza Helena Campana

    2017-01-01

    Full Text Available The mechanisms involved in the uncommon resistance phenotype, carbapenem resistance and broad-spectrum cephalosporin susceptibility, were investigated in 25 Pseudomonas aeruginosa clinical isolates that exhibited this phenotype, which were recovered from three different hospitals located in São Paulo, Brazil. The antimicrobial susceptibility profile was determined by CLSI broth microdilution. β-lactamase-encoding genes were investigated by PCR followed by DNA sequencing. Carbapenem hydrolysis activity was investigated by spectrophotometer and MALDI-TOF assays. The mRNA transcription level of oprD was assessed by qRT-PCR and the outer membrane proteins profile was evaluated by SDS-PAGE. Genetic relationship among P. aeruginosa isolates was assessed by PFGE. Carbapenems hydrolysis was not detected by carbapenemase assay in the carbapenem-resistant and cephalosporin-susceptible P. aueruginosa clinical isolates. OprD decreased expression was observed in all P. aeruginosa isolates by qRT-PCR. The outer membrane protein profile by SDS-PAGE suggested a change in the expression of the 46 kDa porin that could correspond to OprD porin. The isolates were clustered into 17 genotypes without predominance of a specific PFGE pattern. These results emphasize the involvement of multiple chromosomal mechanisms in carbapenem-resistance among clinical isolates of P. aeruginosa, alert for adaptation of P. aeruginosa clinical isolates under antimicrobial selective pressure and make aware of the emergence of an uncommon phenotype among P. aeruginosa clinical isolates.

  6. Throat Carriage Rate and Antimicrobial Resistance of Streptococcus pyogenes In Rural Children in Argentina.

    Science.gov (United States)

    Delpech, Gastón; Sparo, Mónica; Baldaccini, Beatriz; Pourcel, Gisela; Lissarrague, Sabina; García Allende, Leonardo

    2017-03-01

    The aim of this study was to determine the prevalence of asymptomatic carriers of group A β-hemolytic streptococci (GAS) in children living in a rural community and to investigate the association between episodes of acute pharyngitis and carrier status. Throat swabs were collected from September to November 2013 among children 5-13 years of age from a rural community (Maria Ignacia-Vela, Argentina). The phenotypic characterization of isolates was performed by conventional tests. Antimicrobial susceptibility was assayed for penicillin, tetracycline, chloramphenicol, erythromycin, and clindamycin (disk diffusion). The minimum inhibitory concentration was determined for penicillin, cefotaxime, tetracycline, and erythromycin. The carriage of β-hemolytic streptococci was detected in 18.1% of participants, with Streptococcus pyogenes in 18 participants followed by S. dysgalactiae ssp. equisimilis in 5. The highest proportion of GAS was found in 8 to 10-year-old children. No significant association between the number of episodes of acute pharyngitis suffered in the last year and the carrier state was detected ( p >0.05). Tetracycline resistance (55.5%) and macrolide-resistant phenotypes (11.1%) were observed. Resistance to penicillin, cefotaxime, or chloramphenicol was not expressed in any streptococcal isolate. The present study demonstrated significant throat carriage of GAS and the presence of group C streptococci ( S. dysgalactiae ssp. equisimilis ) in an Argentinian rural population. These results point out the need for continuous surveillance of GAS and non-GAS carriage as well as of antimicrobial resistance in highly susceptible populations, such as school-aged rural children. An extended surveillance program including school-aged children from different cities should be considered to estimate the prevalence of GAS carriage in Argentina.

  7. The human gut microbiota as a reservoir for antimicrobial resistance genes

    NARCIS (Netherlands)

    Bülow, E.

    2015-01-01

    In the last decades, the emergence and spread of resistant opportunistic pathogens is compromising the effectiveness of antimicrobial therapies. Understanding the emergence and global spread of drug-resistant microorganisms is thus crucial to combat antimicrobial resistance. The human gut harbors a

  8. Antimicrobial resistant Salmonella enterica and Escherichia coli recovered from dairy operations

    Science.gov (United States)

    Antimicrobial resistance has become a major public health concern and animal agriculture is often implicated as a source of resistant bacteria. The primary objective of this study was to determine prevalence of antimicrobial resistance in Salmonella and E. coli from healthy animals on dairy farms i...

  9. Antimicrobial resistance prevalence of pathogenic and commensal Escherichia coli in food-producing animals in Belgium

    OpenAIRE

    Chantziaras, Ilias; Dewulf, Jeroen; Boyen, Filip; Callens, Benedicte; Butaye, Patrick

    2014-01-01

    In this article, detailed studies on antimicrobial resistance to commensal E. coli (in pigs, meat-producing bovines, broiler chickens and veal calves) and pathogenic E. coli (in pigs and bovines) in Belgium are presented for 2011. Broiler chicken and veal calf isolates of commensal E. coli demonstrated higher antimicrobial resistance prevalence than isolates from pigs and bovines. Fifty percent of E. coli isolates from broiler chickens were resistant to at least five antimicrobials, whereas s...

  10. 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 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....

  11. Adaptive Laboratory Evolution of Antibiotic Resistance Using Different Selection Regimes Lead to Similar Phenotypes and Genotypes

    DEFF Research Database (Denmark)

    Jahn, Leonie Johanna; Munck, Christian; Ellabaan, Mostafa M Hashim

    2017-01-01

    compare the geno- and phenotypes of Escherichia coli after evolution to Amikacin, Piperacillin, and Tetracycline under four different selection regimes. Interestingly, key mutations that confer antibiotic resistance as well as phenotypic changes like collateral sensitivity and cross-resistance emerge...

  12. Antimicrobial Resistance Characteristics and Phylogenetic Groups of Escherichia coli Isolated From Diarrheic Calves in Southeast of Iran

    Directory of Open Access Journals (Sweden)

    Zahedeh Naderi

    2016-11-01

    Full Text Available Background: Antimicrobial resistance is one of the main challenges in diarrheal diseases in human and animals. Regardless to the main reason of the disease, approximately all antimicrobial actions including treatment, control and prevention are mostly centralized against Escherichia coli (E. coli strains. Objectives: This work purposed to antimicrobial resistance (AR and determinate virulence genes and phylogenetic groups in E. coli isolates (n=170 obtained from calves with diarrhea. Materials and methods: Isolates were molecular characterized for 17 AR genes and 3 phylogenetic sequences. AR phenotyping were performed on all strains for 12 antimicrobial agents by using disc diffusion method. Results: All AR genes but qnrS were identified with different prevalence in E. coli isolates that the most common genes were aadA (20%, blaTEM (11.7% and sulII (11.2 % belonging to aminoglycoside, β-lactamase and sulphonamide families, respectively. Resistance to the penicillin and sulphamethoxazole drugs was found in 100% of isolates and followed by tetracycline (73.5%, streptomycin (60%, trimethoprim sulphamethoxazole (56.5% and kanamycin (53.5%. The phylogenetic groups A and B1 considerably surrounded the majority of isolates with the frequency of 65.8% and 30.6%, respectively. Conclusions: In Iran, diarrheic calves have an important role as reservoir of resistant E. coli strains against the some drugs which are registered for treatment of calf diarrhea.

  13. Increasing incidence of resistance to antimicrobials in Sidamo.

    Science.gov (United States)

    Belihu, A; Lindtjorn, B

    1999-07-01

    This study compares the prevailing sensitivity of bacterial isolates to common antimicrobials during the two-year 1985-87, 1990-92 and 1996-97 periods at Yirga Alem Hospital in southern Ethiopia. All specimens were from patients attending the hospital. We studied 1371 specimens, 337,671 and 363 specimens from the periods 1985-87, 1990-92 and 1996-97, respectively. The study confirms earlier observations of widespread resistance to commonly used antibiotics. Significant increases in the rate of resistance during this thirteen-year period were observed for Neisseria gonorrhoea against erythromycin, trimethoprim-sulphamethoxazole and tetracyclines, for Escherichia coli against ampicillin and trimethoprim-sulphamethoxazole and for Proteus species against ampicillin. We observed a decrease in the prevalence of resistance for Klebsiella and Proteus species against chloramphenicol.

  14. Enhancing the role of vaccines in combatting antimicrobial resistance.

    Science.gov (United States)

    Clift, Charles; Salisbury, David M

    2017-12-04

    Interest in addressing antimicrobial resistance (AMR) has grown recently but little effort has been made to consider how existing and new vaccines could impact on AMR. A 2017 Chatham House meeting considered the role of vaccines and how to demonstrate their value through their impact on AMR. Ways existing vaccines have reduced antibiotic prescribing and the prevalence of some resistant organisms were reviewed. Other new vaccines could have a similar impact. In gonorrhoea, where complete resistance has developed, vaccine may be the best option. Valuing the impact of vaccines on AMR was challenging: there were difficult methodological issues and a lack of data for modelling. A participant poll suggested priorities for accelerated vaccine development were tuberculosis, typhoid, influenza, RSV and gonorrhoea. More evidence is needed to convince policymakers but that vaccine development projects should be considered by funders on the same basis as those for new antibiotics or diagnostics. Copyright © 2017. Published by Elsevier Ltd.

  15. Antimicrobial resistance of heterotrophic bacteria in sewage-contaminated rivers.

    Science.gov (United States)

    Garcia-Armisen, Tamara; Vercammen, Ken; Passerat, Julien; Triest, David; Servais, Pierre; Cornelis, Pierre

    2011-01-01

    Sewage-contaminated rivers are ecosystems deeply disturbed by human activity due to the release of heavy metals, organic pollutants and pharmaceuticals as well as faecal and pathogenic micro-organisms, which coexist with the autochthonous microbial population. In this study, we compared the percentage of resistance in faecal and heterotrophic bacteria in rivers with different degrees of sewage pollution. As a matter of fact, no correlation was found neither between the degree of sewage pollution and the percentage of antimicrobial resistant heterotrophic bacteria nor between the number of resistant faecal bacteria and that of resistant heterotrophic bacteria. Most of the resistant isolates from the Zenne river downstream Brussels were multi-resistant and the resistance patterns were similar among the strains of each phylogenetic group. The total microbial community in this polluted river (as evaluated through a 16S rRNA gene clone library analysis) appeared to be dominated by the phyla Proteobacteria and Bacteroidetes while the phylum TM7 was the third most represented. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. Herd-level association between antimicrobial use and antimicrobial resistance in bovine mastitis Staphylococcus aureus isolates on Canadian dairy farms.

    Science.gov (United States)

    Saini, V; McClure, J T; Scholl, D T; DeVries, T J; Barkema, H W

    2012-04-01

    Surveillance of antimicrobial use and resistance is needed to manage antimicrobial resistance in bacteria. In this study, data were collected on antimicrobial use and resistance in Staphylococcus aureus (n=562), isolated from intramammary infections and (sub)clinical mastitis cases on 89 dairy farms in 4 regions of Canada [Alberta, Ontario, Québec, and the Maritime Provinces (Prince Edward Island, Nova Scotia, and New Brunswick)]. Dairy producers were asked to deposit empty drug containers into specially provided receptacles, and antimicrobial drug use rate was calculated to quantify antimicrobial use. Minimum inhibitory concentrations were determined using the Sensititer bovine mastitis plate system (TREK Diagnostic Systems Inc., Cleveland, OH), containing antimicrobials commonly used for mastitis treatment and control. Multivariable logistic regression models were built to determine herd-level risk factors of penicillin, ampicillin, pirlimycin, penicillin-novobiocin combination, tetracycline and sulfadimethoxine resistance in Staph. aureus isolates. Intramammary administration of the penicillin-novobiocin combination for dry cow therapy was associated with penicillin and ampicillin resistance [odds ratio (OR): 2.17 and 3.10, respectively]. Systemic administration of penicillin was associated with penicillin resistance (OR: 1.63). Intramammary administration of pirlimycin for lactating cow mastitis treatment was associated with pirlimycin resistance as well (OR: 2.07). Average herd parity was associated with ampicillin and tetracycline resistance (OR: 3.88 and 0.02, respectively). Average herd size was also associated with tetracycline resistance (OR: 1.02). Dairy herds in the Maritime region had higher odds of penicillin and lower odds of ampicillin resistance than dairy herds in Québec (OR: 2.18 and 0.19, respectively). Alberta dairy herds had lower odds of ampicillin and sulfadimethoxine resistance than dairy herds in Québec (OR: 0.04 and 0.08, respectively

  17. Antimicrobial Peptide Resistance Genes in the Plant Pathogen Dickeya dadantii.

    Science.gov (United States)

    Pandin, Caroline; Caroff, Martine; Condemine, Guy

    2016-11-01

    Modification of teichoic acid through the incorporation of d-alanine confers resistance in Gram-positive bacteria to antimicrobial peptides (AMPs). This process involves the products of the dltXABCD genes. These genes are widespread in Gram-positive bacteria, and they are also found in a few Gram-negative bacteria. Notably, these genes are present in all soft-rot enterobacteria (Pectobacterium and Dickeya) whose dltDXBAC operons have been sequenced. We studied the function and regulation of these genes in Dickeya dadantii dltB expression was induced in the presence of the AMP polymyxin. It was not regulated by PhoP, which controls the expression of some genes involved in AMP resistance, but was regulated by ArcA, which has been identified as an activator of genes involved in AMP resistance. However, arcA was not the regulator responsible for polymyxin induction of these genes in this bacterium, which underlines the complexity of the mechanisms controlling AMP resistance in D. dadantii Two other genes involved in resistance to AMPs have also been characterized, phoS and phoH dltB, phoS, phoH, and arcA but not dltD mutants were more sensitive to polymyxin than the wild-type strain. Decreased fitness of the dltB, phoS, and phoH mutants in chicory leaves indicates that their products are important for resistance to plant AMPs. Gram-negative bacteria can modify their lipopolysaccharides (LPSs) to resist antimicrobial peptides (AMPs). Soft-rot enterobacteria (Dickeya and Pectobacterium spp.) possess homologues of the dlt genes in their genomes which, in Gram-positive bacteria, are involved in resistance to AMPs. In this study, we show that these genes confer resistance to AMPs, probably by modifying LPSs, and that they are required for the fitness of the bacteria during plant infection. Two other new genes involved in resistance were also analyzed. These results show that bacterial resistance to AMPs can occur in bacteria through many different mechanisms that need to be

  18. Antimicrobial resistance and resistance gene determinants in clinical Escherichia coli from different animal species in Switzerland.

    Science.gov (United States)

    Lanz, Roland; Kuhnert, Peter; Boerlin, Patrick

    2003-01-02

    Antimicrobial susceptibility testing was performed on a total of 581 clinical Escherichia coli isolates from diarrhea and edema disease in pigs, from acute mastitis in dairy cattle, from urinary tract infections in dogs and cats, and from septicemia in laying hens collected in Switzerland between 1999 and 2001. Among the 16 antimicrobial agents tested, resistance was most frequent for sulfonamides, tetracycline, and streptomycin. Isolates from swine presented significantly more resistance than those from the other animal species. The distribution of the resistance determinants for sulfonamides, tetracycline, and streptomycin was assessed by hybridization and PCR in resistant isolates. Significant differences in the distribution of resistance determinants for tetracycline (tetA, tetB) and sulfonamides (sulII) were observed between the isolates from swine and those from the other species. Resistance to sulfonamides could not be explained by known resistance mechanisms in more than a quarter of the sulfonamide-resistant and sulfonamide-intermediate isolates from swine, dogs and cats. This finding suggests that one or several new resistance mechanisms for sulfonamides may be widespread among E. coli isolates from these animal species. The integrase gene (intI) from class I integrons was detected in a large proportion of resistant isolates in association with the sulI and aadA genes, thus demonstrating the importance of integrons in the epidemiology of resistance in clinical E. coli isolates from animals.

  19. The Impact of Different Antibiotic Regimens on the Emergence of Antimicrobial-Resistant Bacteria

    Science.gov (United States)

    Magal, Pierre; Olivier, Damien; Ruan, Shigui

    2008-01-01

    Backgroud The emergence and ongoing spread of antimicrobial-resistant bacteria is a major public health threat. Infections caused by antimicrobial-resistant bacteria are associated with substantially higher rates of morbidity and mortality compared to infections caused by antimicrobial-susceptible bacteria. The emergence and spread of these bacteria is complex and requires incorporating numerous interrelated factors which clinical studies cannot adequately address. Methods/Principal Findings A model is created which incorporates several key factors contributing to the emergence and spread of resistant bacteria including the effects of the immune system, acquisition of resistance genes and antimicrobial exposure. The model identifies key strategies which would limit the emergence of antimicrobial-resistant bacterial strains. Specifically, the simulations show that early initiation of antimicrobial therapy and combination therapy with two antibiotics prevents the emergence of resistant bacteria, whereas shorter courses of therapy and sequential administration of antibiotics promote the emergence of resistant strains. Conclusions/Significance The principal findings suggest that (i) shorter lengths of antibiotic therapy and early interruption of antibiotic therapy provide an advantage for the resistant strains, (ii) combination therapy with two antibiotics prevents the emergence of resistance strains in contrast to sequential antibiotic therapy, and (iii) early initiation of antibiotics is among the most important factors preventing the emergence of resistant strains. These findings provide new insights into strategies aimed at optimizing the administration of antimicrobials for the treatment of infections and the prevention of the emergence of antimicrobial resistance. PMID:19112501

  20. Laboratory-based surveillance of current antimicrobial resistance patterns and trends among Staphylococcus aureus: 2005 status in the United States

    Directory of Open Access Journals (Sweden)

    Hogan Patricia

    2006-02-01

    Full Text Available Abstract Background The virulence, antimicrobial resistance, and prevalence of S. aureus underscores the need for up-to-date and extensive insights regarding antimicrobial susceptibility trends. One approach to meet this need is analysis of clinical laboratory – based surveillance data. Methods Data from The Surveillance Network-USA (TSN, an electronic surveillance network that collects microbiology data from 300 clinical microbiology laboratories across the United States, were used as the source for analysis that included prevalence of S. aureus in clinical specimens, MRSA and multi-drug resistance phenotype rates and trends according to patient location, geographic distributions, and specimen source. Results S. aureus was the most prevalent species isolated from inpatient specimens (18.7% of all bacterial isolates and the second most prevalent (14.7% from outpatient specimens. In March 2005 MRSA rates were 59.2%, 55%, and 47.9% for strains from non-ICU inpatients, ICU, and outpatients, respectively. This trend was noted in all nine US Bureau of Census regions and multi-drug resistance phenotypes (resistance to ≥ 3 non-beta-lactams was common among both inpatient MRSA (59.9% and outpatient MRSA (40.8%. Greater than 90% of multi-drug resistant MRSA were susceptible to trimethoprim-sulfamethoxazole, linezolid, and vancomycin. Conclusion Prevalence of MRSA among both inpatient and outpatient specimens continues to increase with multi-drug resistance as a common phenotype. Continued emergence of outpatient MRSA that exhibit multi-drug resistant phenotypes has important implications for developing and evolving outpatient treatment guidelines.

  1. Antimicrobial resistance of bacterial enteropathogens isolated from stools in Madagascar.

    Science.gov (United States)

    Randrianirina, Frederique; Ratsima, Elisoa Hariniana; Ramparany, Lova; Randremanana, Rindra; Rakotonirina, Hanitra Clara; Andriamanantena, Tahiry; Rakotomanana, Fanjasoa; Rajatonirina, Soatiana; Richard, Vincent; Talarmin, Antoine

    2014-02-25

    Diarrheal diseases are a major public health problem in developing countries, and are one of the main causes of hospital admissions in Madagascar. The Pasteur Institute of Madagascar undertook a study to determine the prevalence and the pathogenicity of bacterial, viral and protozoal enteropathogens in diarrheal and non-diarrheal stools of children aged less than 5 years in Madagascar. We present here the results of the analysis of antimicrobial susceptibility of the bacteria isolated during this study. The study was conducted in the community setting in 14 districts of Madagascar from October 2008 to May 2009. Conventional methods and PCR were used to identify the bacteria; antimicrobial susceptibility was determined using an agar diffusion method for enterobacteriaceae and MICs were measured by an agar dilution method for Campylobacter sp. In addition to the strains isolated during this study, Salmonella sp and Shigella sp isolated at the Pasteur Institute of Madagascar from 2005 to 2009 were included in the analysis to increase the power of the study. Twenty-nine strains of Salmonella sp, 35 strains of Shigella sp, 195 strains of diarrheagenic E. coli, 203 strains of C. jejuni and 71 strains of C. coli isolated in the community setting were tested for antibiotic resistance. Fifty-five strains of Salmonella sp and 129 strains of Shigella sp isolated from patients referred to the Pasteur Institute of Madagascar were also included in the study. Many E. coli and Shigella isolates (around 80%) but fewer Salmonella isolates were resistant to ampicillin and trimethoprim/sulfamethoxazole. A small proportion of strains of each species were resistant to ciprofloxacin and only 3% of E. coli strains presented a resistance to third generation cephalosporins due to the production of extended-spectrum beta-lactamases. The resistance of Campylobacter sp to ampicillin was the most prevalent, whereas less than 5% of isolates were resistant to each of the other antibiotics. The

  2. Molecular mechanisms of antimicrobial resistance in fecal Escherichia coli of healthy dogs after enrofloxacin or amoxicillin administration.

    Science.gov (United States)

    Aly, Sherine A; Debavalya, Nipattra; Suh, Sang-Jin; Oryazabal, Omar A; Boothe, Dawn M

    2012-11-01

    Escherichia coli respond to selective pressure of antimicrobial therapy by developing resistance through a variety of mechanisms. The purpose of this study was to characterize the genetic mechanisms of antimicrobial resistance in fecal E. coli after the routine use of 2 popular antimicrobials. Fourteen resistant E. coli isolates, representing predominant clones that emerged in healthy dogs' feces after treatment with either amoxicillin (11 E. coli isolates) or enrofloxacin (3 E. coli isolates), were tested for mutations in DNA gyrase (gyrA and gyrB) and in topoisomerase IV (parC) and for the presence of β-lactamases (bla(TEM), bla(SHV), bla(PSE-1) and bla(CTX-M)) and plasmid-mediated quinolone resistance (qnrA, qnrB, qnrS, aac(6')-Ib, and qepA), by polymerase chain reaction. Escherichia coli isolates cultured following amoxicillin therapy only expressed single-drug resistance to β-lactams, while the isolates cultured from dogs receiving enrofloxacin therapy expressed multidrug resistance (MDR). The use of RND efflux pump inhibitors increased the susceptibility of the 3 MDR E. coli isolates to doxycycline, chloramphenicol, enrofloxacin, and ciprofloxacin, which indicates a role of the efflux pump in the acquisition of the MDR phenotype. Amplification and sequencing of AcrAB efflux pump regulators (soxR, soxS, marR, and acrR) revealed only the presence of a single mutation in soxS in the 3 MDR isolates.

  3. Towards a research agenda for water, sanitation and antimicrobial resistance.

    Science.gov (United States)

    Wuijts, Susanne; van den Berg, Harold H J L; Miller, Jennifer; Abebe, Lydia; Sobsey, Mark; Andremont, Antoine; Medlicott, Kate O; van Passel, Mark W J; de Roda Husman, Ana Maria

    2017-04-01

    Clinically relevant antimicrobial resistant bacteria, genetic resistance elements, and antibiotic residues (so-called AMR) from human and animal waste are abundantly present in environmental samples. This presence could lead to human exposure to AMR. In 2015, the World Health Organization (WHO) developed a Global Action Plan for Antimicrobial Resistance with one of its strategic objectives being to strengthen knowledge through surveillance and research. With respect to a strategic research agenda on water, sanitation and hygiene and AMR, WHO organized a workshop to solicit input by scientists and other stakeholders. The workshop resulted in three main conclusions. The first conclusion was that guidance is needed on how to reduce the spread of AMR to humans via the environment and to introduce effective intervention measures. Second, human exposure to AMR via water and its health impact should be investigated and quantified, in order to compare with other human exposure routes, such as direct transmission or via food consumption. Finally, a uniform and global surveillance strategy that complements existing strategies and includes analytical methods that can be used in low-income countries too, is needed to monitor the magnitude and dissemination of AMR.

  4. Helicobacter pylori Infection in Children. Antimicrobial Resistance and Treatment Response.

    Science.gov (United States)

    Montes, Milagrosa; Villalon, Flor N; Eizaguirre, Francisco J; Delgado, Maider; Muñoz-Seca, Ignacio M; Fernández-Reyes, María; Pérez-Trallero, Emilio

    2015-06-01

    The aim of this study was to determine the appropriateness of the recent recommendations for managing Helicobacter pylori infection in children in a university hospital in Southern Europe. Antimicrobial resistance and response to eradication therapy were also determined. The presence of H. pylori was studied in 143 children: by gastric biopsy culture (GBC), (13)C-urea breath test (UBT) and stool antigen immunochromatography test (SAIT) in 56 children; by GBC and UBT in 20, by GBC and SAIT in 18, and by GBC alone in 49. Antimicrobial susceptibility was determined by E-test. Infection was defined as a positive culture or positivity in both UBT and SAIT. Disease progression was studied in 118 patients. First evaluation of symptoms was carried out at 3-6 months after diagnosis and/or after treatment of the infection. H. pylori was detected in 74 from the 143 children analyzed (100% GBC positive, 98.1% UBT positive, and 58.1% SAIT positive). The main symptom was chronic abdominal pain (n = 121). Macroscopic antral nodularity was observed in 29.7% of infected patients and in 5.8% of uninfected patients, respectively. Resistance to clarithromycin and metronidazole was found in 34.7 and 16.7%, respectively. Eradication when susceptible antimicrobials were used occurred in 78.7% (48/61) versus 37.5% (3/8) when the treatment included a drug with resistance (p = .024). In patients with recurrent abdominal pain, symptoms resolved in 92.9% (39/42) patients with HP eradication versus 42.9% (6/14) without HP eradication (p pylori diagnostic screening and treatment because most of them had only recurrent abdominal pain, but remission of their symptoms was associated with H. pylori eradication. © 2014 John Wiley & Sons Ltd.

  5. Impact of raised without antibiotics practices on occurrences of antimicrobial resistance

    Science.gov (United States)

    Background: The increasing occurrence of antimicrobial-resistant human infections has been attributed to the use of antimicrobials in a variety of applications including food-animal production. "Raised without antibiotics" (RWA) meat production has been offered as a practice to reduce antimicrobial-...

  6. Phenotypic, antimicrobial susceptibility profile and virulence factors of Klebsiella pneumoniae isolated from buffalo and cow mastitic milk

    Science.gov (United States)

    Osman, Kamelia M; Hassan, Hany M; Orabi, Ahmed; Abdelhafez, Ahmed S T

    2014-01-01

    Studies on the prevalence and virulence genes of Klebsiella mastitis pathogens in a buffalo population are undocumented. Also, the association of rmpA kfu, uge, magA, Aerobactin, K1 and K2 virulent factors with K. pneumoniae buffalo, and cow mastitis is unreported. The virulence of K. pneumoniae was evaluated through both phenotypic and molecular assays. In vivo virulence was assessed by the Vero cell cytotoxicity, suckling mouse assay and mice lethality test. Antimicrobial susceptibility was tested by disk diffusion method. The 45 K. pneumoniae isolates from buffalo (n = 10/232) and cow (n = 35/293) milk were isolated (45/525; 8.6%) and screened via PCR for seven virulence genes encoding uridine diphosphate galactose 4 epimerase encoding gene responsible for capsule and smooth lipopolysaccharide synthesis (uge), siderophores (kfu and aerobactin), protectines or invasins (rmpA and magA), and the capsule and hypermucoviscosity (K1 and K2). The most common virulence genes were rmpA, kfu, uge, and magA (77.8% each). Aerobactin and K1 genes were found at medium rates of 66.7% each and K2 (55.6%). The Vero cell cytotoxicity and LD (50) in mice were found in 100% of isolates. A multidrug resistance pattern was observed for 40% of the antimicrobials. The distribution of virulence profiles indicate a role of rmpA, kfu, uge, magA, Aerobactin, and K1 and K2 in pathogenicity of K. pneumoniae in udder infections and invasiveness, and constitutes a threat for vulnerable animals, even more if they are in combination with antibiotic resistance. PMID:24915048

  7. Prevalence and Molecular Characterization of Antimicrobial Resistance in Escherichia coli Isolated from Raw Milk and Raw Milk Cheese in Egypt.

    Science.gov (United States)

    Ombarak, Rabee A; Hinenoya, Atsushi; Elbagory, Abdel-Rahman M; Yamasaki, Shinji

    2018-02-01

    The goal of this study was to examine antimicrobial resistance and characterize the implicated genes in 222 isolates of Escherichia coli from 187 samples of raw milk and the two most popular cheeses in Egypt. E. coli isolates were tested for susceptibility to 12 antimicrobials by a disk diffusion method. Among the 222 E. coli isolates, 66 (29.7%) were resistant to one or more antimicrobials, and half of these resistant isolates showed a multidrug resistance phenotype (resistance to at least three different drug classes). The resistance traits were observed to tetracycline (27.5%), ampicillin (18.9%), streptomycin (18.5%), sulfamethoxazole-trimethoprim (11.3%), cefotaxime (4.5%), kanamycin (4.1%), ceftazidime (3.6%), chloramphenicol (2.3%), nalidixic acid (1.8%), and ciprofloxacin (1.4%). No resistance to fosfomycin and imipenem was observed. Tetracycline resistance genes tetA, tetB, and tetD were detected in 53 isolates, 9 isolates, and 1 isolate, respectively, but tetC was not detected. Aminoglycoside resistance genes strA, strB, aadA, and aphA1 were detected in 41, 41, 11, and 9 isolates, respectively. Sulfonamide resistance genes sul1, sul2, and sul3 were detected in 7, 25, and 3 isolates, respectively. Of 42 ampicillin-resistant isolates, bla TEM , bla CTX-M , and bla SHV were detected in 40, 9, and 3 isolates, respectively, and 10 (23.8%) ampicillin-resistant isolates were found to produce extended-spectrum β-lactamase. Each bla gene of extended-spectrum β-lactamase-producing E. coli was further subtyped to be bla CTX-M-15 , bla CTX-M-104 , bla TEM-1 , and bla SHV-12 . The class 1 integron was also detected in 28 resistant isolates, and three different patterns were obtained by PCR-restriction fragment length polymorphism. Sequencing analysis of the variable region revealed that four isolates had dfrA12/orfF/aadA2, two had aadA22, and one had dfrA1/aadA1. These data suggest that antimicrobial-resistant E. coli are widely distributed in the milk production

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

    Science.gov (United States)

    Clausen, Philip T L C; Zankari, Ea; Aarestrup, Frank M; Lund, Ole

    2016-09-01

    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 with two previously described methods; ResFinder and SRST2, which use an assembly/BLAST method and BWA, respectively, using two datasets with a total of 339 isolates, covering five species, originating from the Oxford University Hospitals NHS Trust and Danish pig farms. The predicted resistance 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. This indicates that information might be lost during assembly. KmerResistance performed significantly better than the other methods, when data were contaminated or only contained few sequence reads. Read mapping is superior to assembly-based methods and the new KmerResistance seemingly outperforms currently available methods particularly when including datasets with few reads. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  9. 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...... antimicrobial classes. Substantial differences between countries were observed in the amount of antimicrobials used to produce 1kg of meat. Moreover, large variations in proportions of resistant bacteria were reported by the different countries, suggesting differences in veterinary practice. Despite...

  10. 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...... different antimicrobials was found for the indicator organism Acinetobacter spp. isolated from composite water-sediment samples. The initial resistance levels prior to the new production cycle were 1. to 5%. After 2 months the levels of resistance to oxytetracycline and sulfamethoxazole reached 100...... compared to the resistance levels at four control farms. In conclusion, integrated fish farming seems to favor antimicrobial-resistant bacteria in the pond environment. This could be attributed to the selective pressure of antimicrobials in the pond environment and/or to the introduction of antimicrobial-resistant...

  11. Epidemiology, Clinical Presentation, Laboratory Diagnosis, Antimicrobial Resistance, and Antimicrobial Management of Invasive Salmonella Infections

    Science.gov (United States)

    Sjölund-Karlsson, Maria; Gordon, Melita A.; Parry, Christopher M.

    2015-01-01

    SUMMARY Salmonella enterica infections are common causes of bloodstream infection in low-resource areas, where they may be difficult to distinguish from other febrile illnesses and may be associated with a high case fatality ratio. Microbiologic culture of blood or bone marrow remains the mainstay of laboratory diagnosis. Antimicrobial resistance has emerged in Salmonella enterica, initially to the traditional first-line drugs chloramphenicol, ampicillin, and trimethoprim-sulfamethoxazole. Decreased fluoroquinolone susceptibility and then fluoroquinolone resistance have developed in association with chromosomal mutations in the quinolone resistance-determining region of genes encoding DNA gyrase and topoisomerase IV and also by plasmid-mediated resistance mechanisms. Resistance to extended-spectrum cephalosporins has occurred more often in nontyphoidal than in typhoidal Salmonella strains. Azithromycin is effective for the management of uncomplicated typhoid fever and may serve as an alternative oral drug in areas where fluoroquinolone resistance is common. In 2013, CLSI lowered the ciprofloxacin susceptibility breakpoints to account for accumulating clinical, microbiologic, and pharmacokinetic-pharmacodynamic data suggesting that revision was needed for contemporary invasive Salmonella infections. Newly established CLSI guidelines for azithromycin and Salmonella enterica serovar Typhi were published in CLSI document M100 in 2015. PMID:26180063

  12. Prevalence and antimicrobial resistance pattern of bacterial meningitis in Egypt

    Science.gov (United States)

    Shaban, Lamyaa; Siam, Rania

    2009-01-01

    Infectious diseases are the leading cause of morbidity and mortality in the developing world. In Egypt bacterial diseases constitute a great burden, with several particular bacteria sustaining the leading role of multiple serious infections. This article addresses profound bacterial agents causing a wide array of infections including but not limited to pneumonia and meningitis. The epidemiology of such infectious diseases and the prevalence of Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae are reviewed in the context of bacterial meningitis. We address prevalent serotypes in Egypt, antimicrobial resistance patterns and efficacy of vaccines to emphasize the importance of periodic surveillance for appropriate preventive and treatment strategies. PMID:19778428

  13. Prevalence and antimicrobial resistance pattern of bacterial meningitis in Egypt

    Directory of Open Access Journals (Sweden)

    Shaban Lamyaa

    2009-09-01

    Full Text Available Abstract Infectious diseases are the leading cause of morbidity and mortality in the developing world. In Egypt bacterial diseases constitute a great burden, with several particular bacteria sustaining the leading role of multiple serious infections. This article addresses profound bacterial agents causing a wide array of infections including but not limited to pneumonia and meningitis. The epidemiology of such infectious diseases and the prevalence of Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae are reviewed in the context of bacterial meningitis. We address prevalent serotypes in Egypt, antimicrobial resistance patterns and efficacy of vaccines to emphasize the importance of periodic surveillance for appropriate preventive and treatment strategies.

  14. How externalities impact an evaluation of strategies to prevent antimicrobial resistance in health care organizations

    Directory of Open Access Journals (Sweden)

    Jenine R. Leal

    2017-06-01

    Full Text Available Abstract Background The rates of antimicrobial-resistant organisms (ARO continue to increase for both hospitalized and community patients. Few resources have been allocated to reduce the spread of resistance on global, national and local levels, in part because the broader economic impact of antimicrobial resistance (i.e. the externality is not fully considered when determining how much to invest to prevent AROs, including strategies to contain antimicrobial resistance, such as antimicrobial stewardship programs. To determine how best to measure and incorporate the impact of externalities associated with the antimicrobial resistance when making resource allocation decisions aimed to reduce antimicrobial resistance within healthcare facilities, we reviewed the literature to identify publications which 1 described the externalities of antimicrobial resistance, 2 described approaches to quantifying the externalities associated with antimicrobial resistance or 3 described macro-level policy options to consider the impact of externalities. Medline was reviewed to identify published studies up to September 2016. Main body An externality is a cost or a benefit associated with one person’s activity that impacts others who did not choose to incur that cost or benefit. We did not identify a well-accepted method of accurately quantifying the externality associated with antimicrobial resistance. We did identify three main methods that have gained popularity to try to take into account the externalities of antimicrobial resistance, including regulation, charges or taxes on the use of antimicrobials, and the right to trade permits or licenses for antimicrobial use. To our knowledge, regulating use of antimicrobials is the only strategy currently being used by health care systems to reduce antimicrobial use, and thereby reduce AROs. To justify expenditures on programs that reduce AROs (i.e. to formally incorporate the impact of the negative externality of

  15. Phylogenomics and antimicrobial resistance of the leprosy bacillus Mycobacterium leprae.

    Science.gov (United States)

    Benjak, Andrej; Avanzi, Charlotte; Singh, Pushpendra; Loiseau, Chloé; Girma, Selfu; Busso, Philippe; Fontes, Amanda N Brum; Miyamoto, Yuji; Namisato, Masako; Bobosha, Kidist; Salgado, Claudio G; da Silva, Moisés B; Bouth, Raquel C; Frade, Marco A C; Filho, Fred Bernardes; Barreto, Josafá G; Nery, José A C; Bührer-Sékula, Samira; Lupien, Andréanne; Al-Samie, Abdul R; Al-Qubati, Yasin; Alkubati, Abdul S; Bretzel, Gisela; Vera-Cabrera, Lucio; Sakho, Fatoumata; Johnson, Christian R; Kodio, Mamoudou; Fomba, Abdoulaye; Sow, Samba O; Gado, Moussa; Konaté, Ousmane; Stefani, Mariane M A; Penna, Gerson O; Suffys, Philip N; Sarno, Euzenir Nunes; Moraes, Milton O; Rosa, Patricia S; Baptista, Ida M F Dias; Spencer, John S; Aseffa, Abraham; Matsuoka, Masanori; Kai, Masanori; Cole, Stewart T

    2018-01-24

    Leprosy is a chronic human disease caused by the yet-uncultured pathogen Mycobacterium leprae. Although readily curable with multidrug therapy (MDT), over 200,000 new cases are still reported annually. Here, we obtain M. leprae genome sequences from DNA extracted directly from patients' skin biopsies using a customized protocol. Comparative and phylogenetic analysis of 154 genomes from 25 countries provides insight into evolution and antimicrobial resistance, uncovering lineages and phylogeographic trends, with the most ancestral strains linked to the Far East. In addition to known MDT-resistance mutations, we detect other mutations associated with antibiotic resistance, and retrace a potential stepwise emergence of extensive drug resistance in the pre-MDT era. Some of the previously undescribed mutations occur in genes that are apparently subject to positive selection, and two of these (ribD, fadD9) are restricted to drug-resistant strains. Finally, nonsense mutations in the nth excision repair gene are associated with greater sequence diversity and drug resistance.

  16. Multiple antimicrobial resistance among Avian Escherichia coli strains in Albania

    Directory of Open Access Journals (Sweden)

    Antonio Camarda

    2010-01-01

    Full Text Available In this study, 101 Escherichia (E. coli isolates from broilers, laying hens and turkeys which had died from colibacillosis, collected from 37 intensive and rural farms in Albania, were tested for antimicrobial susceptibility toward 12 different molecules. The highest levels of resistance were observed for Erythromycin (E (100% Amoxicillin (AMX (99.1%, Tetracycline (TE 30 (96.07%, Streptomycin (STR (93.07% and Neomycin (N30 (85.15%. Considerable resistance was also detected for fluoroquinolones. Moreover, 73.33% of E. coli resistant to at least one fluoroquinolone were also resistant to the two other fluoroquinolones checked. No evident differences were found between the E. coli from intensive and from rural farms. Multiple antibiotic resistance was expressed by all the E. coli tested. 23.63% and 17.39% of E. coli isolated from intensive and rural farms, respectively, were resistant towards all the drugs tested. These data would seem to indicate incorrect use of antibiotics on poultry farms in Albania.

  17. Potential enterovirulence and antimicrobial resistance in Escherichia coli isolates from aquatic environments in Rio de Janeiro, Brazil.

    Science.gov (United States)

    Rebello, Raquel Costa de Luca; Regua-Mangia, Adriana Hamond

    2014-08-15

    Escherichia coli contamination in aquatic ecosystems has emerged as a relevant concern of public health impact, especially in developing areas. In this study, E. coli isolates were recovered from residential, industrial, agricultural, hospital wastewaters and recreational waters and, further characterized according to diarrheagenic potential, phylotyping and antimicrobial resistance phenotype. Among the total 178 E. coli isolates, antimicrobial resistance was detected in 37% to at least one of the 11 antimicrobials tested. The highest percentage of resistant E. coli was recovered from agricultural wastewaters (57.7%) followed by recreational waters (56.4%), hospital (34.5%), residential (22.7%) and industrial wastewaters (22.2%). Twenty-three resistance profiles (I-XXIII) were detected and 17 isolates exhibited the MDR phenotype. 11.2% of the total E. coli isolates carried diarrheagenic markers: astA (7.3%, 13/178), stx1 (2.8%, 05/178), escV (2.2%, 04/178) and estIa (0.6%, 01/178). All isolates harbored the uidA gene. E. coli isolates were mostly found in phylogenetic groups A (91.6%, 163/178) followed by groups D (5%, 09/178) and B2 (3.4%, 06/178). Specific gene combinations characterized E. coli pathotypes as ETEC (01/20), ATEC (04/20) and STEC (05/20) which belonged to A (75%, 15/20), D (15%, 03/20) and B2 (10%, 02/20) phylogroups. Our results revealed the widespread distribution of E. coli in aquatic systems in Rio de Janeiro. The circulation of pathogenic E. coli and antimicrobial resistance within bacterial population represents high risk to ecosystem and human health and highlights epidemiological surveillance and sanitary improvement. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Genome-Wide Identification of Antimicrobial Intrinsic Resistance Determinants in Staphylococcus aureus

    DEFF Research Database (Denmark)

    Vestergaard, Martin; Leng, Bingfeng; Haaber, Jakob

    2016-01-01

    that confer intrinsic resistance to antimicrobial agents may be explored for alternative antimicrobial therapies, by potentiating the efficacy of existing antimicrobials. In this study, we identified the intrinsic resistome to a broad spectrum of antimicrobials in the human pathogen, Staphylococcus aureus. We...... confirmed by E-test to display at least twofold increased susceptibility to one or more antimicrobial agents. The majority of the identified genes have not previously been associated with antimicrobial susceptibility in S. aureus. For example, inactivation of genes encoding for subunits of the ATP synthase...... with the atpA mutant compared to wild type cells with gentamicin at a clinically relevant concentration. Our results demonstrate that many gene products contribute to the intrinsic antimicrobial resistance of S. aureus. Knowledge of these intrinsic resistance determinants provides alternative targets...

  19. Mechanisms and consequences of bacterial resistance to antimicrobial peptides.

    Science.gov (United States)

    Andersson, D I; Hughes, D; Kubicek-Sutherland, J Z

    2016-05-01

    Cationic antimicrobial peptides (AMPs) are an intrinsic part of the human innate immune system. Over 100 different human AMPs are known to exhibit broad-spectrum antibacterial activity. Because of the increased frequency of resistance to conventional antibiotics there is an interest in developing AMPs as an alternative antibacterial therapy. Several cationic peptides that are derivatives of AMPs from the human innate immune system are currently in clinical development. There are also ongoing clinical studies aimed at modulating the expression of AMPs to boost the human innate immune response. In this review we discuss the potential problems associated with these therapeutic approaches. There is considerable experimental data describing mechanisms by which bacteria can develop resistance to AMPs. As for any type of drug resistance, the rate by which AMP resistance would emerge and spread in a population of bacteria in a natural setting will be determined by a complex interplay of several different factors, including the mutation supply rate, the fitness of the resistant mutant at different AMP concentrations, and the strength of the selective pressure. Several studies have already shown that AMP-resistant bacterial mutants display broad cross-resistance to a variety of AMPs with different structures and modes of action. Therefore, routine clinical administration of AMPs to treat bacterial infections may select for resistant bacterial pathogens capable of better evading the innate immune system. The ramifications of therapeutic levels of exposure on the development of AMP resistance and bacterial pathogenesis are not yet understood. This is something that needs to be carefully studied and monitored if AMPs are used in clinical settings. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Molecular epidemiology, antimicrobial susceptibilities and resistance mechanisms of Streptococcus pyogenes isolates resistant to erythromycin and tetracycline in Spain (1994–2006

    Directory of Open Access Journals (Sweden)

    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.

  1. 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 use of antimicrobial agents in the modern farm industry has created a reservoir of resistant bacteria in food animals. Foods of animal origin are often contaminated with enterococci that are likely to contribute resistance genes, virulence factors, or other properties to enterococci IN humans....... 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...... to change the current view that antimicrobial-resistant enterococci from animals pose a threat to human health. On the contrary, antimicrobial resistance genes appear to spread freely between enterococci from different reservoirs, irrespective of their apparent host association....

  2. 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

    to change the current view that antimicrobial-resistant enterococci from animals pose a threat to human health. On the contrary, antimicrobial resistance genes appear to spread freely between enterococci from different reservoirs, irrespective of their apparent host association.......The use of antimicrobial agents in the modern farm industry has created a reservoir of resistant bacteria in food animals. Foods of animal origin are often contaminated with enterococci that are likely to contribute resistance genes, virulence factors, or other properties to enterococci IN humans....... 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...

  3. Use of Colistin and Other Critical Antimicrobials on Pig and Chicken Farms in Southern Vietnam and Its Association with Resistance in Commensal Escherichia coli Bacteria

    Science.gov (United States)

    Nguyen, Hoa M.; Nguyen, Cuong V.; Nguyen, Trung V.; Nguyen, Men T.; Thai, Hieu Q.; Ho, Mai H.; Thwaites, Guy; Ngo, Hoa T.; Baker, Stephen; Carrique-Mas, Juan

    2016-01-01

    ABSTRACT Antimicrobial resistance (AMR) is a global health problem, and emerging semi-intensive farming systems in Southeast Asia are major contributors to the AMR burden. We accessed 12 pig and chicken farms at key stages of production in Tien Giang Province, Vietnam, to measure antimicrobial usage and to investigate the prevalence of AMR to five critical antimicrobials (β-lactams, third-generation cephalosporins, quinolones, aminoglycosides, and polymyxins) and their corresponding molecular mechanisms among 180 Escherichia coli isolates. Overall, 94.7 mg (interquartile range [IQR], 65.3 to 151.1) and 563.6 mg (IQR, 398.9 to 943.6) of antimicrobials was used to produce 1 kg (live weight) of chicken and pig, respectively. A median of 3 (out of 8) critical antimicrobials were used on pig farms. E. coli isolates exhibited a high prevalence of resistance to ampicillin (97.8% and 94.4% for chickens and pigs, respectively), ciprofloxacin (73.3% and 21.1%), gentamicin (42.2% and 35.6%), and colistin (22.2% and 24.4%). The prevalence of a recently discovered colistin resistance gene, mcr-1, was 19 to 22% and had strong agreement with phenotypic colistin resistance. We conducted plasmid conjugation experiments with 37 mcr-1 gene-positive E. coli isolates and successfully observed transfer of the gene in 54.0% of isolates through a plasmid of approximately 63 kb, consistent with one recently identified in China. We found no significant correlation between total use of antimicrobials at the farm level and AMR. These data provide additional insight into the role of mcr-1 in colistin resistance on farms and outline the dynamics of phenotypic and genotypic AMR in semi-intensive farming systems in Vietnam. IMPORTANCE Our study provides accurate baseline information on levels of antimicrobial use, as well as on the dynamics of phenotypic and genotypic resistance for antimicrobials of critical importance among E. coli over the different stages of production in emerging pig and

  4. Use of Colistin and Other Critical Antimicrobials on Pig and Chicken Farms in Southern Vietnam and Its Association with Resistance in Commensal Escherichia coli Bacteria.

    Science.gov (United States)

    Nguyen, Nhung T; Nguyen, Hoa M; Nguyen, Cuong V; Nguyen, Trung V; Nguyen, Men T; Thai, Hieu Q; Ho, Mai H; Thwaites, Guy; Ngo, Hoa T; Baker, Stephen; Carrique-Mas, Juan

    2016-07-01

    Antimicrobial resistance (AMR) is a global health problem, and emerging semi-intensive farming systems in Southeast Asia are major contributors to the AMR burden. We accessed 12 pig and chicken farms at key stages of production in Tien Giang Province, Vietnam, to measure antimicrobial usage and to investigate the prevalence of AMR to five critical antimicrobials (β-lactams, third-generation cephalosporins, quinolones, aminoglycosides, and polymyxins) and their corresponding molecular mechanisms among 180 Escherichia coli isolates. Overall, 94.7 mg (interquartile range [IQR], 65.3 to 151.1) and 563.6 mg (IQR, 398.9 to 943.6) of antimicrobials was used to produce 1 kg (live weight) of chicken and pig, respectively. A median of 3 (out of 8) critical antimicrobials were used on pig farms. E. coli isolates exhibited a high prevalence of resistance to ampicillin (97.8% and 94.4% for chickens and pigs, respectively), ciprofloxacin (73.3% and 21.1%), gentamicin (42.2% and 35.6%), and colistin (22.2% and 24.4%). The prevalence of a recently discovered colistin resistance gene, mcr-1, was 19 to 22% and had strong agreement with phenotypic colistin resistance. We conducted plasmid conjugation experiments with 37 mcr-1 gene-positive E. coli isolates and successfully observed transfer of the gene in 54.0% of isolates through a plasmid of approximately 63 kb, consistent with one recently identified in China. We found no significant correlation between total use of antimicrobials at the farm level and AMR. These data provide additional insight into the role of mcr-1 in colistin resistance on farms and outline the dynamics of phenotypic and genotypic AMR in semi-intensive farming systems in Vietnam. Our study provides accurate baseline information on levels of antimicrobial use, as well as on the dynamics of phenotypic and genotypic resistance for antimicrobials of critical importance among E. coli over the different stages of production in emerging pig and poultry production

  5. Sucralose Increases Antimicrobial Resistance and Stimulates Recovery of Escherichia coli Mutants.

    Science.gov (United States)

    Qu, Yilin; Li, Rongyan; Jiang, Mingshan; Wang, Xiuhong

    2017-07-01

    Because of heavy use of antimicrobials, antimicrobial resistance in bacteria has become of great concern. The effect of some widely used food additives such as sucralose on bacteria in the gut and the environment has also drawn increasing attention. In this study, we investigated the interaction between antimicrobials and sucralose impacting antimicrobial resistance and mutation of Escherichia coli (E. coli). To examine antimicrobial resistance and mutation frequency, different subinhibitory concentrations of sucralose were added to cultures of E.coli BW25113 that were then treated with antimicrobials, oxolinic acid, or moxifloxacin. Then the E.coli were assayed for bacterial survival and recovery of mutants resistant to an unrelated antimicrobial, rifampicin. Pre-treatment of E.coli BW25113 with 1/2 minimal inhibitory concentration (MIC) of sucralose increased the survival rate in oxolinic acid or moxifloxacin. A 1/3 MIC of sucralose increased rifampicin-resistant mutation rate of E.coli BW25113 after 72 h, while rifampicin-resistant mutation rate was increased when co-treated with 1/8 MIC, 1/4 MIC, 1/3 MIC sucralose, and oxolinic acid after 24 h. Sucralose can increase the antimicrobial resistance and mutation frequency of E.coli to some antimicrobials.

  6. 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......, 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...... gradually decreased. Chlorhexidine also gradually reduced biofilm cell number, but was inhibitory at concentrations closer to the MIC than was the case for the antibiotics. Thus S. sanguis in biofilms survived up to 500 times the MIC found in batch culture for up to 48 h....

  7. A decade-long commitment to antimicrobial resistance surveillance in Portugal

    Directory of Open Access Journals (Sweden)

    Catarina Moreira Marinho

    2016-10-01

    Full Text Available Antimicrobial resistance (AMR is a worldwide problem with serious health and economic repercussions. Since the 1940s, underuse, overuse, and misuse of antibiotics have had a significant environmental downside. Large amounts of antibiotics not fully metabolized after use in human and veterinary medicine, and other applications, are annually released into the environment. The result has been the development and dissemination of antibiotic-resistant bacteria due to many years of selective pressure. Surveillance of AMR provides important information that helps in monitoring and understanding how resistance mechanisms develop and disseminate within different environments. Surveillance data is needed to inform clinical therapy decisions, to guide policy proposals, and to assess the impact of action plans to fight AMR. The Functional Genomics and Proteomics Unit, based at the University of Trás-os-Montes and Alto Douro (UTAD in Vila Real, Portugal, has recently completed 10 years of research surveying AMR in bacteria, mainly commensal indicator bacteria such as enterococci and Escherichia coli from the microbiota of different animals. Samples from more than 75 different sources have been accessed, from humans to food-producing animals, pets, and wild animals. The typical microbiological workflow involved phenotypic studies followed by molecular approaches. Throughout the decade, 4,017 samples were collected and over 5,000 bacterial isolates obtained. High levels of AMR to several antimicrobial classes have been reported, including to β-lactams, glycopeptides, tetracyclines, aminoglycosides, sulphonamides and quinolones. Multi-resistant strains, some relevant to human and veterinary medicine like extended-spectrum β-lactamase-producing E. coli and vancomycin-resistant enterococci, have been repeatedly isolated even in non-synanthropic animal species. Of particular relevance are reports of AMR bacteria in wildlife from natural reserves and endangered

  8. The association between measurements of antimicrobial use and resistance in the faeces microbiota of finisher batches.

    Science.gov (United States)

    Andersen, V D; DE Knegt, L V; Munk, P; Jensen, M S; Agersø, Y; Aarestrup, F M; Vigre, H

    2017-10-01

    The objectives were to present three approaches for calculating antimicrobial (AM) use in pigs that take into account the rearing period and rearing site, and to study the association between these measurements and phenotypical resistance and abundance of resistance genes in faeces samples from 10 finisher batches. The AM use was calculated relative to the rearing period of the batches as (i) 'Finisher Unit Exposure' at unit level, (ii) 'Lifetime Exposure' at batch level and (iii) 'Herd Exposure' at herd level. A significant effect on the occurrence of tetracycline resistance measured by cultivation was identified for Lifetime Exposure for the AM class: tetracycline. Furthermore, for Lifetime Exposure for the AM classes: macrolide, broad-spectrum penicillin, sulfonamide and tetracycline use as well as Herd Unit Exposure for the AM classes: aminoglycoside, lincosamide and tetracycline use, a significant effect was observed on the occurrence of genes coding for the AM resistance classes: aminoglycoside, lincosamide, macrolide, β-lactam, sulfonamide and tetracycline. No effect was observed for Finisher Unit Exposure. Overall, the study shows that Lifetime Exposure is an efficient measurement of AM use in finisher batches, and has a significant effect on the occurrence of resistance, measured either by cultivation or metagenomics.

  9. Antimicrobial Resistance Control Strategies: A Coordinated Research Initiative Experience in the Asia Pacific Region.

    Science.gov (United States)

    Lapierre, Lisette; Asenjo, Gabriela; Vergara, Constanza; Cornejo, Javiera

    2017-05-01

    The objective was to gather information on the status of antimicrobial surveillance in the Asia Pacific region and suggest control strategies. Twenty-one economies of the Asia Pacific region participated in this initiative. A survey was conducted on antimicrobial use and surveillance throughout the region. A workshop was carried out to create awareness about the issue and discuss the implementation of control strategies. Based on the survey results and workshop conclusions, it can be established that there is better understanding of the implications of antimicrobial resistance in the human medicine area. Only few economies take actions to control antimicrobial resistance on a veterinary/agricultural level. To confront antimicrobial resistance, it is critical to raise awareness; cooperation between all countries is needed to apply international standards, to be able to have harmonized public policies. Countries must align and improve their systems for surveillance and monitoring of antimicrobial resistance in human, animals, and the environment.

  10. Antimicrobial silver: uses, toxicity and potential for resistance.

    Science.gov (United States)

    Mijnendonckx, Kristel; Leys, Natalie; Mahillon, Jacques; Silver, Simon; Van Houdt, Rob

    2013-08-01

    This review gives a comprehensive overview of the widespread use and toxicity of silver compounds in many biological applications. Moreover, the bacterial silver resistance mechanisms and their spread in the environment are discussed. This study shows that it is important to understand in detail how silver and silver nanoparticles exert their toxicity and to understand how bacteria acquire silver resistance. Silver ions have shown to possess strong antimicrobial properties but cause no immediate and serious risk for human health, which led to an extensive use of silver-based products in many applications. However, the risk of silver nanoparticles is not yet clarified and their widespread use could increase silver release in the environment, which can have negative impacts on ecosystems. Moreover, it is shown that silver resistance determinants are widely spread among environmental and clinically relevant bacteria. These resistance determinants are often located on mobile genetic elements, facilitating their spread. Therefore, detailed knowledge of the silver toxicity and resistance mechanisms can improve its applications and lead to a better understanding of the impact on human health and ecosystems.

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

    Directory of Open Access Journals (Sweden)

    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.

  12. Multidrug-Resistant Enterococcal Infections: New Compounds, Novel Antimicrobial Therapies?

    Science.gov (United States)

    van Harten, Roel M; Willems, Rob J L; Martin, Nathaniel I; Hendrickx, Antoni P A

    2017-06-01

    Over the past two decades infections due to antibiotic-resistant bacteria have escalated world-wide, affecting patient morbidity, mortality, and health care costs. Among these bacteria, Enterococcus faecium and Enterococcus faecalis represent opportunistic nosocomial pathogens that cause difficult-to-treat infections because of intrinsic and acquired resistance to a plethora of antibiotics. In recent years, a number of novel antimicrobial compound classes have been discovered and developed that target Gram-positive bacteria, including E. faecium and E. faecalis. These new antibacterial agents include teixobactin (targeting lipid II and lipid III), lipopeptides derived from nisin (targeting lipid II), dimeric vancomycin analogues (targeting lipid II), sortase transpeptidase inhibitors (targeting the sortase enzyme), alanine racemase inhibitors, lipoteichoic acid synthesis inhibitors (targeting LtaS), various oxazolidinones (targeting the bacterial ribosome), and tarocins (interfering with teichoic acid biosynthesis). The targets of these novel compounds and mode of action make them very promising for further antimicrobial drug development and future treatment of Gram-positive bacterial infections. Here we review current knowledge of the most favorable anti-enterococcal compounds along with their implicated modes of action and efficacy in animal models to project their possible future use in the clinical setting. Copyright © 2017 Elsevier Ltd. All rights reserved.

  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...

  14. Comparative genomics of a drug-resistant Pseudomonas aeruginosa panel and the challenges of antimicrobial resistance prediction from genomes.

    Science.gov (United States)

    Jeukens, J; Kukavica-Ibrulj, I; Emond-Rheault, J G; Freschi, L; Levesque, R C

    2017-10-02

    Antimicrobial resistance (AMR) is now recognized as a global threat to human health. The accessibility of microbial whole-genome sequencing offers an invaluable opportunity for resistance surveillance via the resistome, i.e. the genes and mutations underlying AMR. Unfortunately, AMR prediction from genomic data remains extremely challenging, especially for species with a large pan-genome. One such organism, for which multidrug-resistant (MDR) isolates are frequently encountered in the clinic, is Pseudomonas aeruginosa. This study focuses on a commercially available panel of seven MDR P. aeruginosa strains. The main goals were to sequence and compare these strains' genomes, attempt to predict AMR from whole genomes using two different methods and determine whether this panel could be an informative complement to the international P. aeruginosa reference panel. As expected, the results highlight the complexity of associating genotype and AMR phenotype in P. aeruginosa, mainly due to the intricate regulation of resistance mechanisms. Our results also urge caution in the interpretation of predicted resistomes regarding the occurrence of gene identity discrepancies between strains. We envision that, in addition to accounting for the genomic diversity of P. aeruginosa, future development of predictive tools will need to incorporate a transcriptomic, proteomic and/or metabolomic component. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Prevalence of antimicrobial resistance in fecal Escherichia coli and Salmonella enterica in Canadian commercial meat, companion, laboratory, and shelter rabbits (Oryctolagus cuniculus) and its association with routine antimicrobial use in commercial meat rabbits.

    Science.gov (United States)

    Kylie, Jennifer; McEwen, Scott A; Boerlin, Patrick; Reid-Smith, Richard J; Weese, J Scott; Turner, Patricia V

    2017-11-01

    presence of antimicrobial resistant E. coli or S. enterica on farms; trends towards resistance were present when resistance to specific antimicrobial classes was examined. E. coli was widely prevalent in many Canadian domestic rabbit populations, while S. enterica was rare. The prevalence of AMR in isolated bacteria was variable and most common in isolates from commercial meat rabbits (96% of the AMR isolates were from commercial meat rabbit fecal samples). Our results highlight that domestic rabbits, and particularly meat rabbits, may be carriers of phenotypically antimicrobial-resistant bacteria and AMR genes, possibly contributing to transmission of these bacteria and their genes to bacteria in humans through food or direct contact, as well as to other co-housed animal species. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Antibiotic resistance genes and residual antimicrobials in cattle feedlot surface soil

    Science.gov (United States)

    Cattle feedlot soils receive manure containing both antibiotic residues and antibiotic resistant bacteria. The fates of these constituents are largely unknown with potentially serious consequences for increased antibiotic resistance in the environment. Determine if common antimicrobials (tetracycl...

  17. Antimicrobial consumption and resistance in five Gram-negative bacterial species in a hospital from 2003 to 2011.

    Science.gov (United States)

    Lee, Heng-Sim; Loh, Yue-Xia; Lee, Jen-Jain; Liu, Chang-Shee; Chu, Chishih

    2015-12-01

    The misuse of antimicrobial agents increases drug resistance in bacteria. The correlation between antimicrobial agent consumption and related resistance in the Gram-negative bacteria Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Proteus mirabilis was analyzed during the period 2003-2011. Among these five bacteria, overall E. coli and K. pneumoniae were more commonly isolated from bloodstream than the other species. Regarding Enterobacteriaceae, E. coli and K. pneumoniae showed annual increases of resistance to the tested antimicrobial agents; conversely, P. mirabilis exhibited reduced resistance to cefuroxime, ceftriaxone and cefepime. In contrast to the relatively low antimicrobial resistance in P. aeruginosa, A. baumannii revealed high resistance, which was over 85% resistant rate to the tested antimicrobial agents and over 80% carbapenem resistance in 2011. E. coli, K. pneumoniae, and P. mirabilis differed in development of antimicrobial resistance after consumption of the antimicrobial agents. K. pneumoniae developed resistance to all antimicrobial groups, whereas resistance in P. mirabilis was not related to any antimicrobial consumption. P. aeruginosa developed resistance to β-lactam antimicrobials and aminoglycosides, whereas A. baumanii developed resistance to carbapenems after their use. The development of antimicrobial resistance was related to antimicrobial agents and bacterial species. Copyright © 2014. Published by Elsevier B.V.

  18. 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...

  19. Antimicrobial resistance of Salmonella and E. coli from Pennsylvania dairy herds

    Science.gov (United States)

    Antimicrobial resistance in bacterial pathogens is an increasing public health concern. The objective of this study was to examine antimicrobial resistance in Salmonella and E. coli isolates from Pennsylvania dairy herds. Manure composite samples were collected from 76 farms: on each farm one sample...

  20. Antimicrobial resistance: a global view from the 2013 World Healthcare-Associated Infections Forum

    Science.gov (United States)

    2013-01-01

    Antimicrobial resistance (AMR) is now a global threat. Its emergence rests on antimicrobial overuse in humans and food-producing animals; globalization and suboptimal infection control facilitate its spread. While aggressive measures in some countries have led to the containment of some resistant gram-positive organisms, extensively resistant gram-negative organisms such as carbapenem-resistant enterobacteriaceae and pan-resistant Acinetobacter spp. continue their rapid spread. Antimicrobial conservation/stewardship programs have seen some measure of success in reducing antimicrobial overuse in humans, but their reach is limited to acute-care settings in high-income countries. Outside the European Union, there is scant or no oversight of antimicrobial administration to food-producing animals, while evidence mounts that this administration leads directly to resistant human infections. Both horizontal and vertical infection control measures can interrupt transmission among humans, but many of these are costly and essentially limited to high-income countries as well. Novel antimicrobials are urgently needed; in recent decades pharmaceutical companies have largely abandoned antimicrobial discovery and development given their high costs and low yield. Against this backdrop, international and cross-disciplinary collaboration appears to be taking root in earnest, although specific strategies still need defining. Educational programs targeting both antimicrobial prescribers and consumers must be further developed and supported. The general public must continue to be made aware of the current scale of AMR’s threat, and must perceive antimicrobials as they are: a non-renewable and endangered resource. PMID:24237856

  1. High throughput phenotyping for aphid resistance in large plant collections

    Directory of Open Access Journals (Sweden)

    Chen Xi

    2012-08-01

    Full Text Available Abstract Background Phloem-feeding insects are among the most devastating pests worldwide. They not only cause damage by feeding from the phloem, thereby depleting the plant from photo-assimilates, but also by vectoring viruses. Until now, the main way to prevent such problems is the frequent use of insecticides. Applying resistant varieties would be a more environmental friendly and sustainable solution. For this, resistant sources need to be identified first. Up to now there were no methods suitable for high throughput phenotyping of plant germplasm to identify sources of resistance towards phloem-feeding insects. Results In this paper we present a high throughput screening system to identify plants with an increased resistance against aphids. Its versatility is demonstrated using an Arabidopsis thaliana activation tag mutant line collection. This system consists of the green peach aphid Myzus persicae (Sulzer and the circulative virus Turnip yellows virus (TuYV. In an initial screening, with one plant representing one mutant line, 13 virus-free mutant lines were identified by ELISA. Using seeds produced from these lines, the putative candidates were re-evaluated and characterized, resulting in nine lines with increased resistance towards the aphid. Conclusions This M. persicae-TuYV screening system is an efficient, reliable and quick procedure to identify among thousands of mutated lines those resistant to aphids. In our study, nine mutant lines with increased resistance against the aphid were selected among 5160 mutant lines in just 5 months by one person. The system can be extended to other phloem-feeding insects and circulative viruses to identify insect resistant sources from several collections, including for example genebanks and artificially prepared mutant collections.

  2. Does antimicrobial use increase the rate of antimicrobial resistance? A one year experience

    Directory of Open Access Journals (Sweden)

    H Gedik

    2012-01-01

    Full Text Available Antimicrobial resistance has been a challenge in all countries. The aim of this study is to ascertain the risk factors that predispose patients to infections with extended spectrum beta lactamase (ESBL-producing gram-negative bacteria and methicillin-resistant Staphylococcus aureus (MRSA. Patients who were treated in the secondary care hospital due to infections in 2009 and their isolates were evaluated retrospectively. In total, 174 patients and their 189 isolates, which contained 36 ESBL-producing gram-negative bacteria, 112 non-ESBL-producing gram-negative bacteria, and 41 gram-positive bacteria were evaluated retrospectively. Hospitalisation in the previous 3 months, comorbidity, and usage of amoxicillin-clavulanate in the previous 3 months were determined to be the risk factors associated with infections by the ESBL-producing gram-negative bacteria. Hospitalisation was found to be a risk factor for infection with MRSA. Hospitalisation and underlying conditions increase the colonisation with resistant bacteria and resistance rates in the patients, hospitals and communities. An infection control programme should be contemplated not only for hospitals, but also for the greater community.

  3. Epidemiology of Antimicrobial Resistance in Escherichia coli Isolates from Raccoons (Procyon lotor and the Environment on Swine Farms and Conservation Areas in Southern Ontario.

    Directory of Open Access Journals (Sweden)

    Kristin J Bondo

    Full Text Available Antimicrobial resistance is a global threat to livestock, human and environmental health. Although resistant bacteria have been detected in wildlife, their role in the epidemiology of antimicrobial resistance is not clear. Our objective was to investigate demographic, temporal and climatic factors associated with carriage of antimicrobial resistant Escherichia coli in raccoons and the environment. We collected samples from raccoon paws and feces and from soil, manure pit and dumpsters on five swine farms and five conservation areas in Ontario, Canada once every five weeks from May to November, 2011-2013 and tested them for E. coli and susceptibility to 15 antimicrobials. Of samples testing positive for E. coli, resistance to ≥ 1 antimicrobials was detected in 7.4% (77/1044; 95% CI, 5.9-9.1 of raccoon fecal samples, 6.3% (23/365; 95% CI, 4.0-9.3 of paw samples, 9.6% (121/1260; 8.0-11.4 of soil samples, 57.4% (31/54; 95% CI, 43.2-70.8 of manure pit samples, and 13.8% (4/29; 95% CI, 3.9-31.7 of dumpster samples. Using univariable logistic regression, there was no significant difference in the occurrence of resistant E. coli in raccoon feces on conservation areas versus farms; however, E. coli isolates resistant to ≥ 1 antimicrobials were significantly less likely to be detected from raccoon paw samples on swine farms than conservation areas and significantly more likely to be detected in soil samples from swine farms than conservation areas. Resistant phenotypes and genotypes that were absent from the swine farm environment were detected in raccoons from conservation areas, suggesting that conservation areas and swine farms may have different exposures to resistant bacteria. However, the similar resistance patterns and genes in E. coli from raccoon fecal and environmental samples from the same location types suggest that resistant bacteria may be exchanged between raccoons and their environment.

  4. Epidemiology of Antimicrobial Resistance in Escherichia coli Isolates from Raccoons (Procyon lotor) and the Environment on Swine Farms and Conservation Areas in Southern Ontario.

    Science.gov (United States)

    Bondo, Kristin J; Pearl, David L; Janecko, Nicol; Boerlin, Patrick; Reid-Smith, Richard J; Parmley, Jane; Jardine, Claire M

    2016-01-01

    Antimicrobial resistance is a global threat to livestock, human and environmental health. Although resistant bacteria have been detected in wildlife, their role in the epidemiology of antimicrobial resistance is not clear. Our objective was to investigate demographic, temporal and climatic factors associated with carriage of antimicrobial resistant Escherichia coli in raccoons and the environment. We collected samples from raccoon paws and feces and from soil, manure pit and dumpsters on five swine farms and five conservation areas in Ontario, Canada once every five weeks from May to November, 2011-2013 and tested them for E. coli and susceptibility to 15 antimicrobials. Of samples testing positive for E. coli, resistance to ≥ 1 antimicrobials was detected in 7.4% (77/1044; 95% CI, 5.9-9.1) of raccoon fecal samples, 6.3% (23/365; 95% CI, 4.0-9.3) of paw samples, 9.6% (121/1260; 8.0-11.4) of soil samples, 57.4% (31/54; 95% CI, 43.2-70.8) of manure pit samples, and 13.8% (4/29; 95% CI, 3.9-31.7) of dumpster samples. Using univariable logistic regression, there was no significant difference in the occurrence of resistant E. coli in raccoon feces on conservation areas versus farms; however, E. coli isolates resistant to ≥ 1 antimicrobials were significantly less likely to be detected from raccoon paw samples on swine farms than conservation areas and significantly more likely to be detected in soil samples from swine farms than conservation areas. Resistant phenotypes and genotypes that were absent from the swine farm environment were detected in raccoons from conservation areas, suggesting that conservation areas and swine farms may have different exposures to resistant bacteria. However, the similar resistance patterns and genes in E. coli from raccoon fecal and environmental samples from the same location types suggest that resistant bacteria may be exchanged between raccoons and their environment.

  5. Antimicrobial resistance patterns of Shiga toxin-producing Escherichia coli O157:H7 and O157:H7- from different origins.

    Science.gov (United States)

    Srinivasan, Velusamy; Nguyen, Lien T; Headrick, Susan I; Murinda, Shelton E; Oliver, Stephen P

    2007-01-01

    Shiga toxin-producing Escherichia coli (STEC) serotypes including O157:H7 (n = 129) from dairy cows, cull dairy cow feces, cider, salami, human feces, ground beef, bulk tank milk, bovine feces, and lettuce; and O157:H7- (n = 24) isolated from bovine dairy and bovine feedlot cows were evaluated for antimicrobial resistance against 26 antimicrobials and the presence of antimicrobial resistance genes (tetA, tetB, tetC, tetD, tetE, tetG, floR, cmlA, strA, strB, sulI, sulII, and ampC). All E. coli exhibited resistance to five or more antimicrobial agents, and the majority of isolates carried one or more target antimicrobial resistance gene(s) in different combinations. The majority of E. coli showed resistance to ampicillin, aztreonam, cefaclor, cephalothin, cinoxacin, and nalidixic acid, and all isolates were susceptible to chloramphenicol and florfenicol. Many STEC O157:H7 and O157:H7-isolates were susceptible to amikacin, carbenicillin, ceftriaxone, cefuroxime, ciprofloxacin, fosfomycin, moxalactam, norfloxacin, streptomycin, tobramycin, trimethoprim, and tetracycline. The majority of STEC O157:H7 (79.8%) and O157:H7- (91.7%) carried one or more antimicrobial resistance gene(s) regardless of whether phenotypically resistant or susceptible. Four tetracycline resistant STEC O157:H7 isolates carried both tetA and tetC. Other tetracycline resistance genes (tetB, tetD, tetE, and tetG) were not detected in any of the isolates. Among nine streptomycin resistant STEC O157:H7 isolates, eight carried strA-strB along with aadA, whereas the other isolate carried aadA alone. However, the majority of tetracycline and streptomycin susceptible STEC isolates also carried tetA and aadA genes, respectively. Most ampicillin resistant E. coli of both serotypes carried ampC genes. Among sulfonamide resistance genes, sulII was detected only in STEC O157:H7 (4 of 80 sulfonamide-resistant isolates) and sulI was detected in O157:H7- (1 of 16 sulfonamide resistant isolates). The emergence and

  6. Population dynamics and antimicrobial resistance of the most prevalent poultry-associated Salmonella serotypes.

    Science.gov (United States)

    Shah, Devendra H; Paul, Narayan C; Sischo, Willium C; Crespo, Rocio; Guard, Jean

    2017-03-01

    Salmonella spp. is the most predominant bacterial cause of foodborne gastroenteritis in humans. Due to the risk of human infection associated with poultry products and the prevalence of antimicrobial resistance, Salmonella also poses a significant challenge to commercial poultry production. During the last decade (2002 to 2012), the 12 most prevalent poultry-associated Salmonella serotypes (MPPSTs) were frequently and consistently isolated from poultry products in the United States. These MPPSTs and their percent prevalence in poultry products include Kentucky (4%), Enteritidis (2%) Heidelberg (2%), Typhimurium (2%), S. I 4,[5],12:i:- (0.31%), Montevideo (0.20%), Infantis (0.16%) Schwarzengrund (0.15%), Hadar (0.15%), Mbandaka (0.13%), Thompson (0.12%), and Senftenberg (0.04%). All MPPSTs except Kentucky are among the top 30 clinically significant serotypes that cause human illnesses in the United States. However with the exception of a few widely studied serotypes such as S. Enteritidis and Typhimurium, the ecology and epidemiology of the majority of MPPSTs still remain poorly investigated. Published data from the United States suggests that MPPSTs such as Heidelberg, Typhimurium, Kentucky, and Sentfenberg are more likely to be multi-drug resistant (MDR, ≥3 antimicobial classes) whereas Enteritidis, Montevideo, Schwarzengrund, Hadar, Infantis, Thompson, and Mbandaka are generally pan-susceptible or display resistance to fewer antimicobials. In contrast, the majority of MPPSTs isolated globally have been reported to display MDR phenotype. There also appears to be an international spread of a few MDR serotypes including Kentucky, Schwarzengrund, Hadar, Thomson, Sentfenberg, and Enteritidis, which may pose significant challenges to the public health. The current knowledge gaps on the ecology, epidemiology, and antimicrobial resistance of MPPSTs are discussed. © 2016 Poultry Science Association Inc.

  7. 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.

  8. Increasing antimicrobial resistance in clinical isolates of Staphylococcus intermedius group bacteria and emergence of MRSP in the UK.

    Science.gov (United States)

    Beever, L; Bond, R; Graham, P A; Jackson, B; Lloyd, D H; Loeffler, A

    2015-02-14

    Frequencies of antimicrobial resistance were determined amongst 14,555 clinical Staphylococcus intermedius group (SIG) isolates from UK dogs and cats to estimate resistance trends and quantify the occurrence of meticillin-resistant Staphylococcus pseudintermedius (MRSP). Reports from two diagnostic laboratories (13,313 general submissions, 1242 referral centre only submissions) were analysed retrospectively (2003/2006-2012). MRSP were defined by phenotypic resistance to meticillin and concurrent broad β-lactam resistance; a subset was confirmed genetically (SIG-specific nuc and mecA). Trends were analysed by Cochran-Armitage test. Resistance remained below 10 per cent for cefalexin, amoxicillin-clavulanic acid and the fluoroquinolones. Increasing resistance trends were seen in both laboratories for ampicillin/amoxicillin (both PResistance to cefalexin increased over time in referral hospital isolates (Presistance to important antimicrobials was identified overtime and the emergence of MRSP from UK clinical cases was confirmed. Attention to responsible use of antibacterial therapy in small animal practice is urgently needed. British Veterinary Association.

  9. Bicarbonate induces high-level resistance to the human antimicrobial peptide LL-37 in Staphylococcus aureus small colony variants.

    Science.gov (United States)

    Zhang, Ping; Wright, John A; Tymon, Anna; Nair, Sean P

    2017-12-04

    Staphylococcus aureus small colony variants (SCVs) cause persistent infections and are resistant to cationic antibiotics. Antimicrobial peptides (AMPs) have been suggested as promising alternatives for treating antibiotic-resistant bacteria. We investigated the capacity of the human cationic AMP LL-37 to kill SCVs in the presence of physiological concentrations of bicarbonate, which are reported to alter bacterial membrane permeability and change resistance of bacteria to AMPs. MBCs of LL-37 for S. aureus SCVs with mutations in different genes in the presence and absence of bicarbonate were determined. In the absence of bicarbonate, SCVs of S. aureus strains LS-1 and 8325-4 had the same level of resistance to LL-37 as the parental strain (8 mg/L). In the presence of bicarbonate, hemB, menD and aroD SCVs of LS-1 had high-level resistance to LL-37 (≥128 mg/L) compared with the parental strain (16 mg/L). However, only the aroD SCV of strain 8324-5 showed high-level resistance. 8325-4 harbours mutations in two genes, tcaR and rsbU, which are involved in antimicrobial sensing and the stress response, respectively. When rsbU was repaired in 8325-4 it displayed high-level resistance to LL-37 in the presence of bicarbonate. This phenotype was lost when tcaR was also repaired, demonstrating that RsbU and TcaR are involved in LL-37 resistance in the presence of bicarbonate. S. aureus SCVs would be resistant to high concentrations of LL-37 in niches where there are physiological concentrations of bicarbonate and therefore this AMP may not be effective in combating SCVs. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy.

  10. 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.

  11. A 5-year Surveillance Study on Antimicrobial Resistance of Acinetobacter baumannii Clinical Isolates from a Tertiary Greek Hospital.

    Science.gov (United States)

    Maraki, Sofia; Mantadakis, Elpis; Mavromanolaki, Viktoria Eirini; Kofteridis, Diamantis P; Samonis, George

    2016-09-01

    Acinetobacter baumannii has emerged as a major cause of nosocomial outbreaks. It is particularly associated with nosocomial pneumonia and bloodstream infections in immunocompromised and debilitated patients with serious underlying pathologies. Over the last two decades, a remarkable rise in the rates of multidrug resistance to most antimicrobial agents that are active against A. baumannii has been noted worldwide. We evaluated the rates of antimicrobial resistance and changes in resistance over a 5-year period (2010-2014) in A. baumannii strains isolated from hospitalized patients in a tertiary Greek hospital. Identification of A. baumannii was performed by standard biochemical methods and the Vitek 2 automated system, which was also used for susceptibility testing against 18 antibiotics: ampicillin/sulbactam, ticarcillin, ticarcillin/clavulanic acid, piperacillin, piperacillin/tazobactam, cefotaxime, ceftazidime, cefepime, imipenem, meropenem, gentamicin, amikacin, tobramycin, ciprofloxacin, tetracycline, tigecycline, trimethoprim/sulfamethoxazole, and colistin. Interpretation of susceptibility results was based on the Clinical and Laboratory Standards Institute criteria, except for tigecycline, for which the Food and Drug Administration breakpoints were applied. Multidrug resistance was defined as resistance to ≥3 classes of antimicrobial agents. Overall 914 clinical isolates of A. baumannii were recovered from the intensive care unit (ICU) (n = 493), and medical (n = 252) and surgical (n = 169) wards. Only 4.9% of these isolates were fully susceptible to the antimicrobials tested, while 92.89% of them were multidrug resistant (MDR), i.e., resistant to ≥3 classes of antibiotics. ICU isolates were the most resistant followed by isolates from surgical and medical wards. The most effective antimicrobial agents were, in descending order: colistin, amikacin, trimethoprim/sulfamethoxazole, tigecycline, and tobramycin. Nevertheless, with the exception of colistin

  12. Genotypic relatedness and antimicrobial resistance of Salmonella Heidelberg isolated from chickens and turkeys in the midwestern United States.

    Science.gov (United States)

    Nisar, Muhammad; Kassem, Issmat I; Rajashekara, Gireesh; Goyal, Sagar M; Lauer, Dale; Voss, Shauna; Nagaraja, Kakambi V

    2017-05-01

    Salmonella is one of the most common causes of foodborne illnesses in humans in the United States, and domestic poultry is considered an important source of this pathogen. Salmonella enterica subsp. enterica serovar Heidelberg is the fourth most commonly reported Salmonella from retail meats and food animals in the United States. We assessed the genotypes and antimicrobial resistance phenotypes of Salmonella Heidelberg isolated from various chicken and turkey hatcheries and breeder farms in the Midwest. The genotypes of 33 S. Heidelberg isolates from chickens ( n = 19) and turkeys ( n = 14) were compared using pulsed-field gel electrophoresis analysis. Cluster analysis of the fingerprints showed that the majority of the chicken isolates grouped together with 87% similarity; those from turkeys clustered with 88% similarity. Similarity between chicken and turkey isolates was also high (86%). Isolates from turkeys were generally more genetically diverse than those from chickens. Antimicrobial susceptibility analysis detected resistance to sulfisoxazole (36% of the isolates), streptomycin (33%), gentamicin (27%), tetracycline (24%), ampicillin and amoxicillin-clavulanic acid (15%), cefoxitin (12%), ceftriaxone and ceftiofur (12%), and chloramphenicol (9%). None of the isolates was resistant to azithromycin, ciprofloxacin, or nalidixic acid. Although the number of the isolates was limited in our study, we conclude that S. Heidelberg isolates from the same host generally clustered together and that a considerable number of the isolates were resistant to a number of antimicrobial agents.

  13. Monitoring Antimicrobial Use and Resistance: Comparison with a National Benchmark on Reducing Vancomycin Use and Vancomycin-Resistant Enterococci

    OpenAIRE

    Fridkin, Scott K.; Lawton, Rachel; Edwards, Jonathan R.; Tenover, Fred C.; McGowan, John E.; Gaynes, Robert P.

    2002-01-01

    To determine if local monitoring data on vancomycin use directed quality improvement and decreased vancomycin use or vancomycin-resistant enterococci (VRE), we analyzed data from 50 intensive-care units (ICUs) at 20 U.S. hospitals reporting data on antimicrobial-resistant organisms and antimicrobial agent use. We compared local data with national benchmark data (aggregated from all study hospitals). After data were adjusted for changes in prevalence of methicillin-resistant Staphylococcus aur...

  14. 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.

  15. 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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. 75 FR 52751 - Office of Global Health Affairs; Trans-Atlantic Task Force on Antimicrobial Resistance (TATFAR)

    Science.gov (United States)

    2010-08-27

    ... on Antimicrobial Resistance (TATFAR) AGENCY: Office of Global Health Affairs, HHS. ACTION: Notice of... Antimicrobial Resistance (TATFAR). DATES: A public meeting will be held in Bethesda, MD, on Friday, October 1...) agreed to establish a task force to focus ``on urgent antimicrobial resistance issues focused on...

  17. Antimicrobial resistance among Salmonella enterica serovar Infantis from broiler carcasses in Serbia

    Science.gov (United States)

    Nikolić, A.; Baltić, T.; Velebit, B.; Babić, M.; Milojević, L.; Đorđević, V.

    2017-09-01

    This study aimed to investigate antimicrobial resistance of Salmonella Infantis isolates from poultry carcasses in Serbia. A total of 48 Salmonella isolates were examined for antimicrobial resistance. A panel of 10 antibiotics was selected for testing. Isolates showed resistance to sulfamethoxazole, ceftazidime and cefotaxime (100%). However, the highest number of Salmonella Infantis isolates were sensitive to chloramphenicol. The usage of antibiotics in food producing animals could result in antimicrobial resistance pathogenic bacteria especially Salmonella spp. in poultry, which may be transmitted to humans through the food chain and increase risk of treatment failures.

  18. 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.

  19. Injectable antimicrobials in commercial feedlot cattle and their effect on the nasopharyngeal microbiota and antimicrobial resistance.

    Science.gov (United States)

    Holman, Devin B; Timsit, Edouard; Booker, Calvin W; Alexander, Trevor W

    2018-02-01

    Beef cattle in North America that are deemed to be at high risk of developing bovine respiratory disease (BRD) are frequently administered a metaphylactic antibiotic injection to control the disease. Cattle may also receive in-feed antimicrobials to prevent specific diseases and ionophores to improve growth and feed efficiency. Presently, attempts to evaluate the effects that these medications have on antibiotic resistance in the bovine nasopharyngeal microbiota have been focused on culturable bacteria that are associated with BRD. Therefore, we assessed the effects of injectable antibiotics on the nasopharyngeal microbiota of commercial feedlot cattle in Alberta, Canada, through the first 60 d on feed. Although all cattle in the study were also receiving in-feed chlortetracycline and monensin, the administration of a single injection of either oxytetracycline or tulathromycin at feedlot placement altered the nasopharyngeal microbiota in comparison with the cattle receiving only in-feed antibiotics. Oxytetracycline significantly (P Mycoplasma spp. at feedlot exit compared with the in-feed antibiotic only group. The proportion of the tetracycline resistance gene tet(H) was significantly increased following oxytetracycline injection (P < 0.05). Oxytetracycline also reduced both the number of OTUs and the Shannon diversity index in the nasopharyngeal microbiota (P < 0.05). These results demonstrate that in feedlot cattle receiving subtherapeutic in-feed antimicrobials, the administration of a single injection of either oxytetracycline or tulathromycin resulted in measurable changes to the nasopharyngeal microbiota during the first 60 d following feedlot placement. Copyright © 2017. Published by Elsevier B.V.

  20. Whole-Genome Sequence Analysis of Antimicrobial Resistance Genes in Streptococcus uberis and Streptococcus dysgalactiae Isolates from Canadian Dairy Herds

    Science.gov (United States)

    Vélez, Julián Reyes; Cameron, Marguerite; Rodríguez-Lecompte, Juan Carlos; Xia, Fangfang; Heider, Luke C.; Saab, Matthew; McClure, J. Trenton; Sánchez, Javier

    2017-01-01

    The objectives of this study are to determine the occurrence of antimicrobial resistance (AMR) genes using whole-genome sequence (WGS) of Streptococcus uberis (S. uberis) and Streptococcus dysgalactiae (S. dysgalactiae) isolates, recovered from dairy cows in the Canadian Maritime Provinces. A secondary objective included the exploration of the association between phenotypic AMR and the genomic characteristics (genome size, guanine–cytosine content, and occurrence of unique gene sequences). Initially, 91 isolates were sequenced, and of these isolates, 89 were assembled. Furthermore, 16 isolates were excluded due to larger than expected genomic sizes (>2.3 bp × 1,000 bp). In the final analysis, 73 were used with complete WGS and minimum inhibitory concentration records, which were part of the previous phenotypic AMR study, representing 18 dairy herds from the Maritime region of Canada (1). A total of 23 unique AMR gene sequences were found in the bacterial genomes, with a mean number of 8.1 (minimum: 5; maximum: 13) per genome. Overall, there were 10 AMR genes [ANT(6), TEM-127, TEM-163, TEM-89, TEM-95, Linb, Lnub, Ermb, Ermc, and TetS] present only in S. uberis genomes and 2 genes unique (EF-TU and TEM-71) to the S. dysgalactiae genomes; 11 AMR genes [APH(3′), TEM-1, TEM-136, TEM-157, TEM-47, TetM, bl2b, gyrA, parE, phoP, and rpoB] were found in both bacterial species. Two-way tabulations showed association between the phenotypic susceptibility to lincosamides and the presence of linB (P = 0.002) and lnuB (P genes and the between the presence of tetM (P = 0.015) and tetS (P = 0.064) genes and phenotypic resistance to tetracyclines only for the S. uberis isolates. The logistic model showed that the odds of resistance (to any of the phenotypically tested antimicrobials) was 4.35 times higher when there were >11 AMR genes present in the genome, compared with genes (P resistance was lower for S. dysgalactiae than S. uberis (P = 0

  1. Molecular serotyping and antimicrobial resistance profiles of Actinobacillus pleuropneumoniae isolated from pigs in South Korea.

    Science.gov (United States)

    Kim, Boram; Hur, Jin; Lee, Ji Yeong; Choi, Yoonyoung; Lee, John Hwa

    2016-09-01

    Actinobacillus pleuropneumoniae (APP) causes porcine pleuropneumonia (PP). Serotypes and antimicrobial resistance patterns in APP isolates from pigs in Korea were examined. Sixty-five APP isolates were genetically serotyped using standard and multiplex PCR (polymerase chain reaction). Antimicrobial susceptibilities were tested using the standardized disk-agar method. PCR was used to detect β-lactam, gentamicin and tetracycline-resistance genes. The random amplified polymorphic DNA (RAPD) patterns were determined by PCR. Korean pigs predominantly carried APP serotypes 1 and 5. Among 65 isolates, one isolate was sensitive to all 12 antimicrobials tested in this study. Sixty-two isolates was resistant to tetracycline and 53 isolates carried one or five genes including tet(B), tet(A), tet(H), tet(M)/tet(O), tet(C), tet(G) and/or tet(L)-1 markers. Among 64 strains, 9% and 26.6% were resistance to 10 and three or more antimicrobials, respectively. Thirteen different antimicrobial resistance patterns were observed and RAPD analysis revealed a separation of the isolates into two clusters: cluster II (6 strains resistant to 10 antimicrobials) and cluster I (the other 59 strains). Results show that APP serotypes 1 and 5 are the most common in Korea, and multi-drug resistant strains are prevalent. RAPD analysis demonstrated that six isolates resistant to 10 antimicrobials belonged to the same cluster.

  2. Spatial patterns of Antimicrobial Resistance Genes in Danish Pig Farms

    DEFF Research Database (Denmark)

    Birkegård, Anna Camilla; Ersbøll, A. K.; Hisham Beshara Halasa, Tariq

    2016-01-01

    antimicrobial resistance genes, ermB, ermF, sulI, sulII, tet(M), tet(O) and tet(W), was quantified by a high-throughput qPCR. It was evaluated whether the sample method resulted in a study population representative of Danish pig farms with finishers where it was found that the study population was biased......Samples from 687 Danish pig farms were collected at five finisher slaughterhouses in February and March 2015. Faecal samples from five pigs per farm were collected randomly at the slaughter line and pooled into one sample per farm. DNA was extracted from the pooled samples and the level of seven...

  3. Antimicrobial blue light inactivation of Methicillin-resistant Staphylococcus aureus

    Science.gov (United States)

    Wang, Yucheng; Dai, Tianhong; Gu, Ying

    2016-10-01

    Background: With the increasing emergence of multidrug-resistant (MDR) bacterial strains, there is a pressing need for the development of alternative treatment for infections. Antimicrobial blue light (aBL) has provided a simple and effective approach. Methods: We first investigated the effectiveness of aBL (415 nm) inactivation of USA300 LAClux (a communityacquired Methicillin-resistant Staphylococcus aureus strain) both in the planktonic and biofilm forms. The survival of the bacteria in suspensions was determined by serial dilution and that of the biofilm-embedded bacteria was determined by bioluminescence quantification. Using a mouse model of thermal burn infected with USA300 LAClux, we further assessed the effectiveness of aBL for treating localized infections. Bioluminescence imaging was performed to monitor in real time bacterial viability in vivo. Results: In vitro study showed that, for the planktonic counterpart of the bacteria or the 24-h-old biofilms, an irradiance of 55 mW/cm2 for 60 min resulted in a 4.61 log10 or 2.56 log10 inactivation, respectively. In vivo study using infected mouse burns demonstrated that a 2.56-log10 inactivation was achieved after 100-mW/cm2 irradiation for 62 min. Conclusions: aBL is a potential alternative approach for treating Methicillin-resistant Staphylococcus aureus infections.

  4. The streptomycin-sulfadiazine-tetracycline antimicrobial resistance element of calf-adapted Escherichia coli is widely distributed among isolates from Washington state cattle.

    Science.gov (United States)

    Khachatryan, Artashes R; Besser, Thomas E; Call, Douglas R

    2008-01-01

    Association of specific antimicrobial resistance patterns with unrelated selective traits has long been implicated in the maintenance of antimicrobial resistance in a population. Previously we demonstrated that Escherichia coli strains with a specific resistance pattern (resistant to streptomycin, sulfadiazine, and tetracycline [SSuT]) have a selective advantage in dairy calf intestinal environments and in the presence of a milk supplement commonly fed to the calves. In the present study we identified the sequence of the genetic element that confers the SSuT phenotype and show that this element is present in a genetically diverse group of E. coli isolates, as assessed by macrorestriction digestion and pulsed-field gel electrophoresis. This element was also found in E. coli isolates from 18 different cattle farms in Washington State. Using in vitro competition experiments we further demonstrated that SSuT strains from 17 of 18 farms were able to outcompete pansusceptible strains. In a separate set of experiments, we were able to transfer the antimicrobial resistance phenotype by electroporation to a laboratory strain of E. coli (DH10B), making that new strain more competitive during in vitro competition with the parental DH10B strain. These data indicate that a relatively large genetic element conferring the SSuT phenotype is widely distributed in E. coli from cattle in Washington State. Furthermore, our results indicate that this element is responsible for maintenance of these traits owing to linkage to genetic traits that confer a selective advantage in the intestinal lumens of dairy calves.

  5. Antimicrobial Resistance Patterns of Isolated Vibrio cholerae Strains

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    Masood Hajia

    2016-02-01

    Full Text Available Background: Cholera is a potentially life-threatening acute diarrheal disease caused by the toxigenic bacteria, Vibrio cholerae. Antibiotics should be selected using local antibiotic susceptibility testing patterns. Objectives: This study was performed to identify the patterns of antimicrobial resistance in isolates collected from laboratory-confirmed cases of cholera during three years, from 2011 to 2013. Materials and Methods: All isolates at the Health Reference Laboratory were tested by the Minimum Inhibitory Concentration (MIC Test using Liofilchem against ciprofloxacin, nalidixic acid, cefixime, ampicillin, tetracycline, trimethoprim-sulfamethoxazole, and erythromycin. The following organisms were used as quality control strains for MIC E-testing; Escherichia coli (ATCC 25922, Staphylococcus aureus (ATCC 29213, and Pseudomonas aeruginosa (ATCC 27853. Results: Results of susceptibility testing showed complete sensitivity to ciprofloxacin, cefixime and amplicillin for both isolated Inaba and Ogawa serotypes except all isolated Inaba serotypes from year 2011, which were resistant to cefixime. These resistant Inaba serotypes were not isolated in the next year. Inaba serotypes showed an increased resistance rate of up to 100% to nalidixic acid, tetracycline and trimethoprim-sulfamethaxazone, while Ogawa serotypes were 100% sensitive at the end of year 2013. The susceptibility pattern of erytromycine was similar in these two types. Sensitivity to erythromycin was decreased in both Inaba and Ogawa serotypes. Conclusions: The analyzed results indicate that tetracycline should not be considered as a first line antibiotic therapy for patients infected with Ogawa serotypes. Also, national guidelines for confirmation of cholera should be improved by responsible authorities to cover new resistance during outbreaks.

  6. SCC mec typing and antimicrobial resistance of methicillin-resistant Staphylococcus aureus (MRSA) from pigs of Northeast India.

    Science.gov (United States)

    Rajkhowa, S; Sarma, D K; Pegu, S R

    2016-12-01

    Staphylococcus aureus is one of the most important pathogens of both humans and animal. Methicillin-resistant Staphylococcus aureus (MRSA) is an important human pathogen that causes serious infections both in hospitals and communities due to its multidrug resistance tendency. This study was undertaken to characterize the MRSA isolates from pigs and to determine the antimicrobial resistance of these isolates. Forty nine MRSA strains (one strain per positive pig) isolated from pigs of Northeast India were characterized by SCCmec typing and antimicrobial resistance. The overall prevalence of MRSA was 7.02 % with the highest prevalence recorded in pigs aged 1-3 months (P = 0.001) and in nasal samples (P = 0.005). Two SCC mec types (type III and V) were found in Indian pigs with predominance of type V. All isolates were resistant to penicillin. Seventeen resistance groups were observed where 87.75 % isolates showed multidrug resistance (showed resistance to three or more classes of antimicrobials). The most predominant resistance pattern observed was Oxytetracycline + Penicillin + Sulfadiazine + Tetracycline accounting 12.24 % of the isolates. The present study contributes to the understanding of characteristics and antimicrobial resistance of porcine MRSA isolates which in turn will help in devising strategy for the control of this pathogen. Findings of the study also throw light on multidrug resistance MRSA and emphasize the need for judicious use of antimicrobials in animal practice.

  7. Comparative analysis of phenotypic and genotypic detection of methicillin resistance among Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Tulin Demir

    2016-01-01

    Full Text Available Aims: Staphylococcus aureus is a common pathogen causing a wide range of infections ranging from mild skin and soft tissue infections to severe, life-threatening infections. Accuracy in the detection of methicillin resistance is important to avoid treatment failures. The aim of this study was to compare the results of phenotypic and genotypic test methods to detect methicillin resistance and also to determine the antimicrobial susceptibilities. Materials and Methods: Two hundred and forty-two S. aureus strains isolated from skin and soft tissue samples were analyzed for methicillin resistance using oxacillin and cefoxitin disk diffusion (DD, oxacillin screen agar test, cefoxitin E-test, and mecA gene polymerase chain reaction (PCR. Results: 77 of 242 S. aureus isolates were mecA positive. Oxacillin, cefoxitin DD, oxacillin screen agar test and cefoxitin E-test exhibited sensitivities as 98.7%, 98.7%, 100%, 100%, and specificities as 96.9%, 97.5%, 96.9%, 97.5%, respectively. Conclusion: Results of oxacillin screen agar and cefoxitin DD test were in concordance with mecA gene PCR. Thus, it is determined that especially cefoxitin test can be an alternative to PCR in routine.

  8. Understanding bacterial resistance to antimicrobial peptides: From the surface to deep inside.

    Science.gov (United States)

    Maria-Neto, Simone; de Almeida, Keyla Caroline; Macedo, Maria Ligia Rodrigues; Franco, Octávio Luiz

    2015-11-01

    Resistant bacterial infections are a major health problem in many parts of the world. The major commercial antibiotic classes often fail to combat common bacteria. Although antimicrobial peptides are able to control bacterial infections by interfering with microbial metabolism and physiological processes in several ways, a large number of cases of resistance to antibiotic peptide classes have also been reported. To gain a better understanding of the resistance process various technologies have been applied. Here we discuss multiple strategies by which bacteria could develop enhanced antimicrobial peptide resistance, focusing on sub-cellular regions from the surface to deep inside, evaluating bacterial membranes, cell walls and cytoplasmic metabolism. Moreover, some high-throughput methods for antimicrobial resistance detection and discrimination are also examined. This article is part of a Special Issue entitled: Bacterial Resistance to Antimicrobial Peptides. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Eight-Year Surveillance of Antimicrobial Resistance among Enterobacter Cloacae Isolated in the First Bethune Hospital

    Science.gov (United States)

    Zhou, Qi; Zhang, Man; Wang, Ailin; Xu, Jiancheng; Yuan, Ye

    This study was to investigate the antimicrobial resistance of Enterobacter cloacae 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 683 strains of Enterobacter cloacae were collected from sputum 410 (60.0%), secretions and pus 105 (15.4%), urine 69 (10.1%) during the past 8 years. No Enterobacter cloacae was resistant to imipenem and meropenem in the First Bethune Hospital. The antimicrobial resistance of Enterobacter cloacae 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 b eing transmitted.

  10. Surveillance of antimicrobial resistance among Escherichia coli from chicken and swine, China, 2008-2015.

    Science.gov (United States)

    Zhang, Peng; Shen, Zhangqi; Zhang, Chunping; Song, Li; Wang, Bing; Shang, Jun; Yue, Xiuying; Qu, Zhina; Li, Xinnan; Wu, Liqin; Zheng, Yongjun; Aditya, Anand; Wang, Yang; Xu, Shixin; Wu, Congming

    2017-05-01

    The objective of this study was to investigate the antimicrobial resistance trend in Escherichia coli from food animals in China. During 2008-2015, a total of 15,130 E. coli were isolated from chicken and swine from seven provinces. The susceptibilities of these isolates to nine classes of antimicrobial agents were determined using broth microdilution susceptibility method. The findings of this study include: (1) multi-drug resistance was highly prevalent in E. coli; (2) these E. coli isolates showed high resistant rate (>80%) to several old drugs, including ampicillin, tetracycline and sulfisoxazole; (3) increasing resistance to colistin, florfenicol and ceftiofur was observed; (4) the E. coli isolates from different provinces had different resistance patterns. All these data highlight the rising problem of antimicrobial resistance. It is urgent to improve the management of animal production and enhance the proper use of antimicrobials in China as well as the other countries. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Subinhibitory Concentrations of Ciprofloxacin Enhance Antimicrobial Resistance and Pathogenicity of Enterococcus faecium.

    Science.gov (United States)

    Sinel, Clara; Cacaci, Margherita; Meignen, Pierrick; Guérin, François; Davies, Bryan W; Sanguinetti, Maurizio; Giard, Jean-Christophe; Cattoir, Vincent

    2017-05-01

    Enterococcus faecium has emerged as a major opportunistic pathogen for 2 decades with the spread of hospital-adapted multidrug-resistant clones. As members of the intestinal microbiota, they are subjected to numerous bacterial stresses, including antibiotics at subinhibitory concentrations (SICs). Since fluoroquinolones are extensively prescribed, SICs are very likely to occur in vivo , with potential effects on bacterial metabolism with subsequent modulation of opportunistic traits. The aim of this study was to evaluate globally the impact of SICs of ciprofloxacin on antimicrobial resistance and pathogenicity of E. faecium Transcriptomic analysis was performed by RNA sequencing (RNA-seq) (HiSeq 2500; Illumina) using the vanB -positive reference strain E. faecium Aus0004 in the absence or presence of ciprofloxacin SIC (0.38 mg/liter, i.e., 1/8 of the MIC). Several genetic and phenotypic tests were used for validation. In the presence of ciprofloxacin SIC, 196 genes were significantly induced, whereas 286 genes were significantly repressed, meaning that 16.8% of the E. faecium genome was altered. Among upregulated genes, EFAU004_02294 (fold change, 14.3) encoded a protein (Qnr of E. faecium [EfmQnr]) homologue of Qnr proteins involved in quinolone resistance in Gram-negative bacilli. Its implication in intrinsic and adaptive fluoroquinolone (FQ) resistance in E. faecium was experimentally ascertained. Moreover, EFAU004_02292, coding for the collagen adhesin Acm, was also induced by the SIC of ciprofloxacin (fold change, 8.2), and higher adhesion capabilities were demonstrated phenotypically. Both EfmQnr and Acm determinants may play an important role in the transition from a commensal to a pathogenic state of E. faecium that resides in the gut of patients receiving fluoroquinolone therapy. Copyright © 2017 American Society for Microbiology.

  12. Inappropriate use of antibiotics in hospitals: the complex relationship between antibiotic use and antimicrobial resistance.

    Science.gov (United States)

    Cantón, Rafael; Horcajada, Juan Pablo; Oliver, Antonio; Garbajosa, Patricia Ruiz; Vila, Jordi

    2013-09-01

    Hospitals are considered an excellent compartment for the selection of resistant and multi-drug resistant (MDR) bacteria. The overuse and misuse of antimicrobial agents are considered key points fuelling this situation. Antimicrobial stewardship programs have been designed for better use of these compounds to prevent the emergence of resistant microorganisms and to diminish the upward trend in resistance. Nevertheless, the relationship between antibiotic use and antimicrobial resistance is complex, and the desired objectives are difficult to reach. Various factors affecting this relationship have been advocated including, among others, antibiotic exposure and mutant selection windows, antimicrobial pharmacodynamics, the nature of the resistance (natural or acquired, including mutational and that associated with horizontal gene transfer) and the definition of resistance. Moreover, antimicrobial policies to promote better use of these drugs should be implemented not only in the hospital setting coupled with infection control programs, but also in the community, which should also include animal and environmental compartments. Within hospitals, the restriction of antimicrobials, cycling and mixing strategies and the use of combination therapies have been used to avoid resistance. Nevertheless, the results have not always been favorable and resistant bacteria have persisted despite the theoretical benefits of these strategies. Mathematical models as well as microbiological knowledge can explain this failure, which is mainly related to the current scenario involving MDR bacteria and overcoming the fitness associated with resistance. New antimicrobials, rapid diagnostic and antimicrobial susceptibility testing and biomarkers will be useful for future antimicrobial stewardship interventions. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  13. Multivariable Analysis of the Association Between Antimicrobial Use and Antimicrobial Resistance in Escherichia coli Isolated from Apparently Healthy Pigs in Japan.

    Science.gov (United States)

    Makita, Kohei; Goto, Masaki; Ozawa, Manao; Kawanishi, Michiko; Koike, Ryoji; Asai, Tetsuo; Tamura, Yutaka

    2016-01-01

    The objective of this study was to investigate the association between antimicrobial agent use and antimicrobial resistance in Escherichia coli isolated from healthy pigs using data from 2004 to 2007 in the Japanese Veterinary Antimicrobial Resistance Monitoring System (JVARM). Fecal E. coli isolates from 250 pigs (one isolate each from a pig per farm) were examined for antimicrobial resistance. Information on the use of antimicrobials within preceding 6 months and types of farms recorded in JVARM was collected and statistically analyzed against the resistance patterns. In the univariate analysis, associations between both therapeutic and feed additive use of antimicrobials, and resistance to dihydrostreptomycin, gentamicin, kanamycin, ampicillin, cefazolin, ceftiofur, oxytetracycline, chloramphenicol, trimethoprim, nalidixic acid, enrofloxacin, colistin, and bicozamycin, and husbandry factors were investigated. In multivariable analysis, generalized estimating equations were used to control geographical intraclass correlation. Confounding for structurally unrelated associations was tested using generalized linear models. The results suggested direct and cross selections in the associations between use of aminoglycosides in reproduction farms and resistance to kanamycin, use of tetracyclines in larger farms and resistance to oxytetracycline, use of beta-lactams and resistance to ampicillin, use of phenicols and resistance to chloramphenicol, and use of fluoroquinolones and resistance to nalidixic acid and enrofloxacin. Coselection was suggested in the use of tetracyclines and chloramphenicol resistance. The associations between use of beta-lactams and dihydrostreptomycin resistance, use of macrolides and ampicillin and oxytetracycline resistance, and use of colistin and kanamycin resistance were significant, but were confounded by the simultaneous use of homologous antimicrobials.

  14. Ability of Latin America laboratories to detect antimicrobial resistance patterns: experience of the SENTRY antimicrobial surveillance program (1997-2000

    Directory of Open Access Journals (Sweden)

    Rodrigo E. Mendes

    Full Text Available The accuracy of antimicrobial susceptibility tests is a crucial step for the clinical management of patients with serious infections. They must be reliable and precise because they will guide antimicrobial therapy. Our main objective was to compare the results of susceptibility testing performed by the SENTRY coordinator laboratory with those reported by the participating Latin American medical centers. A total of 10,277 bacterial isolates were tested by the reference broth microdilution method at the coordinator laboratory in the United States. The tests were performed and interpreted following the National Committee for Clinical Laboratory Standards (NCCLS recommendations. Ten antimicrobial agent-organism combinations were analyzed. The susceptibility methods utilized in each of the medical centers were also evaluated. Total agreement of the results was obtained in nearly 88% of the antimicrobial agent-organism combinations. "Very major" (false-susceptible results and "major errors" (false-resistant results were observed in 12% and 6% of the cases, respectively. The highest disagreements were observed for coagulase-negative Staphylococcus - oxacillin (20% - very major error and Burkholderia cepacia - imipenem (21% - very major error. The susceptibility method with the highest agreement rate was Etest® (92% > PASCO® (91% > agar dilution (91% > MicroScan® (90% > Vitek® (87%. External quality assurance data obtained by surveillance programs such as the SENTRY Antimicrobial Surveillance Program are not only helpful for detecting the emergence of patterns of antimicrobial resistance, but also to monitor the performance of the participating microbiology laboratories.

  15. Ability of Latin America laboratories to detect antimicrobial resistance patterns: experience of the SENTRY antimicrobial surveillance program (1997-2000

    Directory of Open Access Journals (Sweden)

    Mendes Rodrigo E.

    2003-01-01

    Full Text Available The accuracy of antimicrobial susceptibility tests is a crucial step for the clinical management of patients with serious infections. They must be reliable and precise because they will guide antimicrobial therapy. Our main objective was to compare the results of susceptibility testing performed by the SENTRY coordinator laboratory with those reported by the participating Latin American medical centers. A total of 10,277 bacterial isolates were tested by the reference broth microdilution method at the coordinator laboratory in the United States. The tests were performed and interpreted following the National Committee for Clinical Laboratory Standards (NCCLS recommendations. Ten antimicrobial agent-organism combinations were analyzed. The susceptibility methods utilized in each of the medical centers were also evaluated. Total agreement of the results was obtained in nearly 88% of the antimicrobial agent-organism combinations. "Very major" (false-susceptible results and "major errors" (false-resistant results were observed in 12% and 6% of the cases, respectively. The highest disagreements were observed for coagulase-negative Staphylococcus - oxacillin (20% - very major error and Burkholderia cepacia - imipenem (21% - very major error. The susceptibility method with the highest agreement rate was Etest® (92% > PASCO® (91% > agar dilution (91% > MicroScan® (90% > Vitek® (87%. External quality assurance data obtained by surveillance programs such as the SENTRY Antimicrobial Surveillance Program are not only helpful for detecting the emergence of patterns of antimicrobial resistance, but also to monitor the performance of the participating microbiology laboratories.

  16. Systematic analysis of funding awarded for antimicrobial resistance research to institutions in the UK, 19972010

    OpenAIRE

    Head, Michael G.; Fitchett, Joseph R.; Cooke, Mary K.; Wurie, Fatima B.; Atun, Rifat; Hayward, Andrew C.; Holmes, Alison; Johnson, Alan P.; Woodford, Neil

    2014-01-01

    Objectives: To assess the level of research funding awarded to UK institutions specifically for antimicrobial resistance-related research and how closely the topics funded relate to the clinical and public health burden of resistance.Methods: Databases and web sites were systematically searched for information on how infectious disease research studies were funded for the period 1997–2010. Studies specifically related to antimicrobial resistance, including bacteriology, virology, mycology and...

  17. Antibiotic Stewardship Initiatives as Part of the UK 5-Year Antimicrobial Resistance Strategy

    OpenAIRE

    Johnson, Alan P.; Ashiru-Oredope, Diane; Beech, Elizabeth

    2015-01-01

    Antibiotic use is a major driver for the emergence and spread of antibiotic resistance. Antimicrobial stewardship programmes aim to improve antibiotic prescribing with the objectives of optimizing clinical outcomes while at the same time minimizing unintended consequences such as adverse effects and the selection of antibiotic resistance. In 2013, a five-year national strategy for tackling antimicrobial resistance was published in the UK. The overarching goal of the strategy is to slow the de...

  18. Insights into novel antimicrobial compounds and antibiotic resistance genes from soil metagenomes

    OpenAIRE

    de Castro, Alinne P.; Fernandes, Gabriel da R.; Franco, Octávio L.

    2014-01-01

    In recent years a major worldwide problem has arisen with regard to infectious diseases caused by resistant bacteria. Resistant pathogens are related to high mortality and also to enormous healthcare costs. In this field, cultured microorganisms have been commonly focused in attempts to isolate antibiotic resistance genes or to identify antimicrobial compounds. Although this strategy has been successful in many cases, most of the microbial diversity and related antimicrobial molecules have be...

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

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    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.

  20. Biofilm Formation, Antimicrobial Resistance, and Sanitizer Tolerance of Salmonella enterica Strains Isolated from Beef Trim.

    Science.gov (United States)

    Wang, Rong; Schmidt, John W; Harhay, Dayna M; Bosilevac, Joseph M; King, David A; Arthur, Terrance M

    2017-12-01

    In the beef industry, product contamination by Salmonella enterica is a serious public health concern, which may result in human infection and cause significant financial loss due to product recalls. Currently, the precise mechanism and pathogen source responsible for Salmonella contamination in commercial establishments are not well understood. We characterized 89 S. enterica strains isolated from beef trim with respect to their biofilm-forming ability, antimicrobial resistance, and biofilm cell survival/recovery growth after sanitizer exposure. A total of 28 Salmonella serovars was identified within these strains. The most common serovars identified were Anatum, Dublin, Montevideo, and Typhimurium, with these accounting for nearly half of the total strains. The vast majority (86%) of the strains was able to develop strong biofilms, and the biofilm-forming ability was highly strain dependent and related to cell surface expression of extracellular polymeric structures. These strains also demonstrated strong tolerance to quaternary ammonium chloride (QAC) and chlorine dioxide (ClO 2 ), but were more sensitive to chlorine treatment. Sanitizer tolerance and bacterial postsanitization recovery growth were closely associated with strains' biofilm-forming ability. Thirty percent of the examined strains were found resistant to multiple antimicrobial agents and the resistance phenotypes were serovar associated, but not related to strains' biofilm-forming ability. Pulsed-field gel electrophoresis analysis tended to group strains by serovar rather than by biofilm-forming ability. Collectively, these data indicate that the strong biofilm formers of certain S. enterica strains/serovars possess significant potential for causing meat product contamination in meat processing environment.

  1. Diversity and antimicrobial resistance of Salmonella enterica isolates from surface water in Southeastern United States.

    Science.gov (United States)

    Li, Baoguang; Vellidis, George; Liu, Huanli; Jay-Russell, Michele; Zhao, Shaohua; Hu, Zonglin; Wright, Anita; Elkins, Christopher A

    2014-10-01

    A study of prevalence, diversity, and antimicrobial resistance of Salmonella enterica in surface water in the southeastern United States was conducted. A new scheme was developed for recovery of Salmonella from irrigation pond water and compared with the FDA's Bacteriological Analytical Manual (8th ed., 2014) (BAM) method. Fifty-one isolates were recovered from 10 irrigation ponds in produce farms over a 2-year period; nine Salmonella serovars were identified by pulsed-field gel electrophoresis analysis, and the major serovar was Salmonella enterica serovar Newport (S. Newport, n = 29), followed by S. enterica serovar Enteritidis (n = 6), S. enterica serovar Muenchen (n = 4), S. enterica serovar Javiana (n = 3), S. enterica serovar Thompson (n = 2), and other serovars. It is noteworthy that the PulseNet patterns of some of the isolates were identical to those of the strains that were associated with the S. Thompson outbreaks in 2010, 2012, and 2013, S. Enteritidis outbreaks in 2011 and 2013, and an S. Javiana outbreak in 2012. Antimicrobial susceptibility testing confirmed 16 S. Newport isolates of the multidrug resistant-AmpC (MDR-AmpC) phenotype, which exhibited resistance to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (ACSSuT), and to the 1st, 2nd, and 3rd generations of cephalosporins (cephalothin, amoxicillin-clavulanic acid, and ceftriaxone). Moreover, the S. Newport MDR-AmpC isolates had a PFGE pattern indistinguishable from the patterns of the isolates from clinical settings. These findings suggest that the irrigation water may be a potential source of contamination of Salmonella in fresh produce. The new Salmonella isolation scheme significantly increased recovery efficiency from 21.2 (36/170) to 29.4% (50/170) (P = 0.0002) and streamlined the turnaround time from 5 to 9 days with the BAM method to 4 days and thus may facilitate microbiological analysis of environmental water. Copyright © 2014, American Society for

  2. Fate and transport of antimicrobials and antimicrobial resistance genes in soil and runoff following land application of swine manure slurry.

    Science.gov (United States)

    Joy, Stacey R; Bartelt-Hunt, Shannon L; Snow, Daniel D; Gilley, John E; Woodbury, Bryan L; Parker, David B; Marx, David B; Li, Xu

    2013-01-01

    Due to the use of antimicrobials in livestock production, residual antimicrobials and antimicrobial resistance genes (ARGs) could enter the environment following the land application of animal wastes and could further contaminate surface and groundwater. The objective of this study was to determine the effect of various manure land application methods on the fate and transport of antimicrobials and ARGs in soil and runoff following land application of swine manure slurry. Swine manure slurries were obtained from facilities housing pigs that were fed chlortetracyline, tylosin or bacitracin and were land applied via broadcast, incorporation, and injection methods. Three rainfall simulation tests were then performed on amended and control plots. Results show that land application methods had no statistically significant effect on the aqueous concentrations of antimicrobials in runoff. However, among the three application methods tested broadcast resulted in the highest total mass loading of antimicrobials in runoff from the three rainfall simulation tests. The aqueous concentrations of chlortetracyline and tylosin in runoff decreased in consecutive rainfall events, although the trend was only statistically significant for tylosin. For ARGs, broadcast resulted in significantly higher erm genes in runoff than did incorporation and injection methods. In soil, the effects of land application methods on the fate of antimicrobials in top soil were compound specific. No clear trend was observed in the ARG levels in soil, likely because different host cells may respond differently to the soil environments created by various land application methods.

  3. Genome-wide identification of antimicrobial intrinsic resistance determinants in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Martin Vestergaard

    2016-12-01

    Full Text Available The emergence of antimicrobial resistance severely threatens our ability to treat bacterial infections. While acquired resistance has received considerable attention, relatively little is known of intrinsic resistance that allows bacteria to naturally withstand antimicrobials. Gene products that confer intrinsic resistance to antimicrobial agents may be explored for alternative antimicrobial therapies, by potentiating the efficacy of existing antimicrobials. In this study, we identified the intrinsic resistome to a broad spectrum of antimicrobials in the human pathogen, Staphylococcus aureus. We screened the Nebraska Transposon Mutant Library of 1920 single-gene inactivations in S. aureus strain JE2, for increased susceptibility to the anti-staphylococcal antimicrobials (ciprofloxacin, oxacillin, linezolid, fosfomycin, daptomycin, mupirocin, vancomycin and gentamicin. 68 mutants were confirmed by E-test to display at least two-fold increased susceptibility to one or more antimicrobial agents. The majority of the identified genes have not previously been associated with antimicrobial susceptibility in S. aureus. For example, inactivation of genes encoding for subunits of the ATP synthase, atpA, atpB, atpG and atpH, reduced the minimum inhibitory concentration (MIC of gentamicin 16-fold. To elucidate the potential of the screen, we examined treatment efficacy in the Galleria mellonella infection model. Gentamicin efficacy was significantly improved, when treating larvae infected with the atpA mutant compared to wild type cells with gentamicin at a clinically relevant concentration. Our results demonstrate that many gene products contribute to the intrinsic antimicrobial resistance of S. aureus. Knowledge of these intrinsic resistance determinants provides alternative targets for compounds that may potentiate the efficacy of existing antimicrobial agents against this important pathogen.

  4. Genome-Wide Identification of Antimicrobial Intrinsic Resistance Determinants inStaphylococcus aureus.

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    Vestergaard, Martin; Leng, Bingfeng; Haaber, Jakob; Bojer, Martin S; Vegge, Christina S; Ingmer, Hanne

    2016-01-01

    The emergence of antimicrobial resistance severely threatens our ability to treat bacterial infections. While acquired resistance has received considerable attention, relatively little is known of intrinsic resistance that allows bacteria to naturally withstand antimicrobials. Gene products that confer intrinsic resistance to antimicrobial agents may be explored for alternative antimicrobial therapies, by potentiating the efficacy of existing antimicrobials. In this study, we identified the intrinsic resistome to a broad spectrum of antimicrobials in the human pathogen, Staphylococcus aureus . We screened the Nebraska Transposon Mutant Library of 1920 single-gene inactivations in S. aureus strain JE2, for increased susceptibility to the anti-staphylococcal antimicrobials (ciprofloxacin, oxacillin, linezolid, fosfomycin, daptomycin, mupirocin, vancomycin, and gentamicin). Sixty-eight mutants were confirmed by E -test to display at least twofold increased susceptibility to one or more antimicrobial agents. The majority of the identified genes have not previously been associated with antimicrobial susceptibility in S. aureus . For example, inactivation of genes encoding for subunits of the ATP synthase, atpA , atpB , atpG and atpH , reduced the minimum inhibitory concentration (MIC) of gentamicin 16-fold. To elucidate the potential of the screen, we examined treatment efficacy in the Galleria mellonella infection model. Gentamicin efficacy was significantly improved, when treating larvae infected with the atpA mutant compared to wild type cells with gentamicin at a clinically relevant concentration. Our results demonstrate that many gene products contribute to the intrinsic antimicrobial resistance of S. aureus . Knowledge of these intrinsic resistance determinants provides alternative targets for compounds that may potentiate the efficacy of existing antimicrobial agents against this important pathogen.

  5. Antimicrobial resistance of Campylobacter species isolated from edible bivalve molluscs purchased from Bangkok markets, Thailand.

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    Soonthornchaikul, Nantika; Garelick, Hemda

    2009-10-01

    Campylobacter species have been recognized as the most commonly reported cause of bacterial gastroenteritis in humans. The increase of resistance rates to drugs of choice used for treatment in campylobacteriosis is becoming a public health concern. In parallel, the increased use of antimicrobials in aquaculture may lead to the emergence of resistant microorganisms and is likely to cause additional health risk to humans through food consumption. The study assesses the presence of antimicrobial resistance in Campylobacter species isolated from three groups of bivalve molluscs (bloody cockles, green mussels, and oysters) purchased from markets in Bangkok. Thirty samples were collected from each group. Susceptibility to three antimicrobials was determined using the Epsilometer test. Rates of erythromycin, nalidixic acid, and ciprofloxacin resistance in Campylobacter isolates were 72-84%, 28-40%, and 21-25%, respectively. There was no statistically significant difference in the prevalence of each antimicrobial resistance between the three groups. This study demonstrates a significant level of antimicrobial resistance in the Campylobacter spp. isolated from molluscs with a particular high rate of resistance to erythromycin. Consumption of raw molluscs contaminated with antimicrobial-resistant Campylobacter spp. may therefore result in resistant infections in humans.

  6. Antimicrobial resistance among Enterobacteriaceae in South America: history, current dissemination status and associated socioeconomic factors.

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    Bonelli, Raquel Regina; Moreira, Beatriz Meurer; Picão, Renata Cristina

    2014-04-01

    South America exhibits some of the higher rates of antimicrobial resistance in Enterobactericeae worldwide. This continent includes 12 independent countries with huge socioeconomic differences, where the ample access to antimicrobials, including counterfeit ones, coexists with ineffective health systems and sanitation problems, favoring the emergence and dissemination of resistant strains. This work presents a literature review concerning the evolution and current status of antimicrobial resistance threats found among Enterobacteriaceae in South America. Resistance to β-lactams, fluoroquinolones and aminoglycosides was emphasized along with description of key epidemiological studies that highlight the success of specific resistance determinants in different parts of the continent. In addition, a discussion regarding political and socioeconomic factors possibly related to the dissemination of antimicrobial resistant strains in clinical settings and at the community is presented. Finally, in order to assess the possible sources of resistant bacteria, we compile the current knowledge about the occurrence of antimicrobial resistance in isolates in South American' food, food-producing animals and off-hospitals environments. By addressing that intensive intercontinental commerce and tourism neutralizes the protective effect of geographic barriers, we provide arguments reinforcing that globally integrated efforts are needed to decelerate the emergence and dissemination of antimicrobial resistant strains. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Escherichia coli isolates from sick chickens in China: changes in antimicrobial resistance between 1993 and 2013.

    Science.gov (United States)

    Chen, Xiang; Zhang, Weiqiu; Yin, Jiajun; Zhang, Ning; Geng, Shizhong; Zhou, Xiaohui; Wang, Yanhong; Gao, Song; Jiao, Xinan

    2014-10-01

    The use of antimicrobials for the control of infectious disease has increased in recent decades. Understanding trends in antimicrobial resistance provides clues about the relationship between antimicrobial use and the emergence of resistance. We examined the resistance of 540 Escherichia coli isolates to 19 antimicrobials that represent 11 classes of antimicrobial agents. The isolates were collected from chickens between 1993 and 2013 in China. Overall, >96.7% of the isolates were resistant to at least one of the tested compounds, and 87.2% of them displayed multidrug resistance (MDR) representing five to six antimicrobial classes. A high proportion of E. coli isolates were resistant to tetracycline (90.6%), nalidixic acid (80.6%), ampicillin (77.2%), trimethoprim-sulfamethoxazole (76.9%), and streptomycin (72.8%). Only 3.0% of the isolates were resistant to nitrofurantoin, and none was resistant to meropenem. Resistance to amikacin, ampicillin, aztreonam, ceftazidime, cefotaxime, cephalothin, chloramphenicol, ciprofloxacin, fosfomycin, levofloxacin, norfloxacin, nalidixic acid, piperacillin, and trimethoprim-sulfamethoxazole significantly increased from 1993 to 2013 (P <0.01). There was an increasing trend in MDR over the 20 year period. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Antimicrobial-Resistant Enterococci in Animals and Meat: A Human Health Hazard?

    DEFF Research Database (Denmark)

    Hammerum, A.M.; Lester, C.H.; Heuer, Ole Eske

    2010-01-01

    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...... 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...

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

    Science.gov (United States)

    Garner, Michael J; Carson, Carolee; Lingohr, Erika J; Fazil, Aamir; Edge, Victoria L; Trumble Waddell, Jan

    2015-01-01

    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

  10. 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

  11. Antimicrobial resistance among pathogenic bacteria from mink (Neovison vison) in Denmark.

    Science.gov (United States)

    Nikolaisen, Nanett Kvist; Lassen, Desireé Corvera Kløve; Chriél, Mariann; Larsen, Gitte; Jensen, Vibeke Frøkjær; Pedersen, Karl

    2017-09-13

    For proper treatment of bacterial infections in mink, knowledge of the causative agents and their antimicrobial susceptibility patterns is crucial. The used antimicrobials are in general not registered for mink, i.e. most usage is "off-label". In this study, we report the patterns of antimicrobial resistance among pathogenic bacteria isolated from Danish mink during the period 2014-2016. The aim of this investigation was to provide data on antimicrobial resistance and consumption, to serve as background knowledge for new veterinary guidelines for prudent and optimal antimicrobial usage in mink. A total number of 308 Escherichia coli isolates, 41 Pseudomonas aeruginosa, 36 Streptococcus canis, 30 Streptococcus dysgalactiae, 55 Staphylococcus delphini, 9 Staphylococcus aureus, and 20 Staphylococcus schleiferi were included in this study. Among E. coli, resistance was observed more frequently among the hemolytic isolates than among the non-hemolytic ones. The highest frequency of resistance was found to ampicillin, 82.3% and 48.0% of the hemolytic of the non-hemolytic isolates, respectively. The majority of the P. aeruginosa isolates were only sensitive to ciprofloxacin and gentamicin. Among the Staphylococcus spp., the highest occurrence of resistance was found for tetracycline. Regarding the nine S. aureus, one isolate was resistant to cefoxitin indicating it was a methicillin-resistant Staphylococcus aureus. Both β-hemolytic Streptococcus species showed high levels of resistance to tetracycline and erythromycin. The antimicrobial consumption increased significantly during 2007-2012, and fluctuated at a high level during 2012-2016, except for a temporary drop in 2013-2014. The majority of the prescribed antimicrobials were aminopenicillins followed by tetracyclines and macrolides. The study showed that antimicrobial resistance was common in most pathogenic bacteria from mink, in particular hemolytic E. coli. There is a need of guidelines for prudent use of

  12. Profile of antimicrobial resistance of bacteria isolated from cockroaches (Periplaneta americana) in a Brazilian health care institution.

    Science.gov (United States)

    Prado, Marinésia Aparecida; Gir, Elucir; Pereira, Milca Severino; Reis, Cleomenes; Pimenta, Fabiana Cristina

    2006-02-01

    Cockroaches carry microorganisms to sterilized materials, equipment and non-contaminated food in hospitals and in homes. Hence, they are regarded as major microbial vectors. We isolated and identified microorganisms from living cockroaches captured from a Brazilian health care institution and we determined the antimicrobial susceptibility profile of the isolates. Following collection, cockroaches were immobilized at 4 degrees C for 10 to 20 minutes, immersed in 0.8% saline solution and then homogenized. Next, the suspension was seeded in culture media: brain and heart agar infusion, MacConkey agar, Naito agar, and they were incubated for up to 48 hours at 37 degrees C. Sabouraud agar cultures were incubated at ambient temperature. The microbial colonies were analyzed with a stereomicroscope to count and phenotypically identify the colony-forming units (cfu). The disc-diffusion method was used to determine the profile of susceptibility to antimicrobials. Among the 103 cockroaches analyzed, fungi were found in 97%, enterobacteria in 74.6% and coagulase-negative staphylococci (CNS) in 25.40%. Among the enterobacteria, 96% were resistant to gentamicin, 84% to ampicillin, 75.3% to caphalothin, 66.7% to ampicillin-sulbactam, 50% to aztreonam and 30% to chloramphenicol. Among the CNS, 61% were resistant to oxacillin. We concluded that cockroaches carry organisms associated with nosocomial infections and that are resistant to antimicrobials. This fact contributes to the epidemiological chain, complicating therapeutics, and consequently, medical costs are increased.

  13. Profile of antimicrobial resistance of bacteria isolated from cockroaches (Periplaneta americana in a Brazilian health care institution

    Directory of Open Access Journals (Sweden)

    Marinésia Aparecida Prado

    Full Text Available Cockroaches carry microorganisms to sterilized materials, equipment and non-contaminated food in hospitals and in homes. Hence, they are regarded as major microbial vectors. We isolated and identified microorganisms from living cockroaches captured from a Brazilian health care institution and we determined the antimicrobial susceptibility profile of the isolates. Following collection, cockroaches were immobilized at 4ºC for 10 to 20 minutes, immersed in 0.8% saline solution and then homogenized. Next, the suspension was seeded in culture media: brain and heart agar infusion, MacConkey agar, Naito agar, and they were incubated for up to 48 hours at 37ºC. Sabouraud agar cultures were incubated at ambient temperature. The microbial colonies were analyzed with a stereomicroscope to count and phenotypically identify the colony-forming units (cfu. The discdiffusion method was used to determine the profile of susceptibility to antimicrobials. Among the 103 cockroaches analyzed, fungi were found in 97%, enterobacteria in 74.6% and coagulase-negative staphylococci (CNS in 25.40%. Among the enterobacteria, 96% were resistant to gentamicin, 84% to ampicillin, 75.3% to caphalothin, 66.7% to ampicillin-sulbactam, 50% to aztreonam and 30% to chloramphenicol. Among the CNS, 61% were resistant to oxacillin. We concluded that cockroaches carry organisms associated with nosocomial infections and that are resistant to antimicrobials. This fact contributes to the epidemiological chain, complicating therapeutics, and consequently, medical costs are increased.

  14. DNA replication proteins as potential targets for antimicrobials in drug-resistant bacterial pathogens.

    Science.gov (United States)

    van Eijk, Erika; Wittekoek, Bert; Kuijper, Ed J; Smits, Wiep Klaas

    2017-05-01

    With the impending crisis of antimicrobial resistance, there is an urgent need to develop novel antimicrobials to combat difficult infections and MDR pathogenic microorganisms. DNA replication is essential for cell viability and is therefore an attractive target for antimicrobials. Although several antimicrobials targeting DNA replication proteins have been developed to date, gyrase/topoisomerase inhibitors are the only class widely used in the clinic. Given the numerous essential proteins in the bacterial replisome that may serve as a potential target for inhibitors and the relative paucity of suitable compounds, it is evident that antimicrobials targeting the replisome are underdeveloped so far. In this review, we report on the diversity of antimicrobial compounds targeting DNA replication and highlight some of the challenges in developing new drugs that target this process. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy.

  15. Different phenotypic and molecular mechanisms associated with multidrug resistance in Gram-negative clinical isolates from Egypt

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    Helmy OM

    2017-12-01

    Full Text Available Omneya M Helmy, Mona T Kashef Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, Egypt Objectives: We set out to investigate the prevalence, different mechanisms, and clonal relatedness of multidrug resistance (MDR among third-generation cephalosporin-resistant Gram-negative clinical isolates from Egypt.Materials and methods: A total of 118 third-generation cephalosporin-resistant Gram-negative clinical isolates were included in this study. Their antimicrobial susceptibility pattern was det