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Sample records for antimicrobial resistance prevalence

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

    PubMed

    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. PMID

  2. Prevalence and antimicrobial resistance of Salmonella recovered from processed poultry.

    PubMed

    Parveen, Salina; Taabodi, Maryam; Schwarz, Jurgen G; Oscar, Thomas P; Harter-Dennis, Jeanine; White, David G

    2007-11-01

    This study was conducted to determine the prevalence and antimicrobial resistance of Salmonella isolates recovered from processed poultry. Four hundred eighty pre- and postchill whole broiler chicken carcasses were collected from a poultry processing plant between July 2004 and June 2005. Water samples also were collected at the entrance and exit of the chiller. After preenrichment, carcass and water samples were analyzed for the presence of Salmonella using the automated BAX system followed by traditional culture methods. The proportions of pre- and postchill carcasses that were positive for Salmonella were 88.4 and 84.1%, respectively. Ninety-two percent of water samples collected at the entrance of the chiller were positive for Salmonella, but all exit samples were negative. There was no significant difference in the prevalence of Salmonella between pre- and postchill carcasses (P > 0.05). Salmonella isolates recovered were serotyped and tested for susceptibility to antimicrobials. Thirteen serotypes were identified; the most common were Salmonella Kentucky (59.5%) and Salmonella Typhimurium (17.8%). Three hundred thirty-nine (79.8%) of the isolates were resistant to at least one antimicrobial, and 53.4% were resistant to three or more antimicrobials. Resistance was most often observed to tetracycline (73.4% of isolates), ampicillin (52.9%), amoxicillin-clavulanic acid (52%), ceftiofur (51.7%), streptomycin (35.2%), and sulfisoxazole (21.8%). These results indicate the high prevalence of Salmonella contamination in whole broiler carcasses, and a large number of these Salmonella isolates were resistant to commonly used antimicrobials. PMID:18044422

  3. Prevalence and antimicrobial resistance in Escherichia coli from food and animals in Lagos, Nigeria

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background Foodborne bacteria are often associated with human infections; these infections can become more complicated to treat if the bacteria are also resistant to antimicrobials. In this study, prevalence, antimicrobial resistance, and genetic relatedness of Escherichia coli among food producing ...

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

    PubMed

    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.

  5. Prevalence and antimicrobial resistance in Escherichia coli from food animals in Lagos, Nigeria

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foodborne bacteria are often associated with human infections; these infections can become more complicated to treat if the bacteria are also resistant to antimicrobials. In this study, prevalence, antimicrobial resistance, and genetic relatedness of Escherichia coli among food producing animals fr...

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

    PubMed

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

    2016-05-01

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

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

    PubMed

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

    2016-05-01

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

  8. Prevalence and Antimicrobial Resistance of Salmonella Isolated from Cattle Feces in United States Feedlots in 2011.

    PubMed

    Dargatz, David A; Kopral, Christine A; Erdman, Matthew M; Fedorka-Cray, Paula J

    2016-09-01

    The objective of this study was to determine the prevalence and characteristics of Salmonella spp. isolated from feces of cattle in feedlots in the United States. Fecal samples were collected from up to three pens of cattle in each of 68 feedlots in 12 states. Samples included up to 25 individual fecal pats from the pen floors and up to five composite samples from the floors of the same pens. The prevalence of Salmonella-positive samples was 9.1% (460/5050) and 11.3% (114/1009) for individual and composite samples, respectively. The prevalences of Salmonella at the pen level were 35.6% (72/202) and 22.8% (46/202) for individual and composite samples, respectively. Dietary factors, including inclusion of cottonseed hulls, coccidiostats, and antimicrobial drugs, were associated with differences in prevalence of Salmonella isolation. Overall, 32 serotypes of Salmonella were identified, but six serotypes accounted for 69.1% (495/716) of the isolates. Nearly two-thirds (64.7%, 44/68) of feedlots had at least one positive sample. All isolates were evaluated for susceptibility to a panel of 15 antimicrobial drugs. Most isolates (74.4%, 533/716) were susceptible to all antimicrobial drugs in the panel. When resistance was detected, it was most commonly to tetracycline (21.7%, 155/716 of isolates) or sulfisoxazole (12.4%, 89/716 of isolates). Less than 10% of the isolates were resistant to any other antimicrobials in the panel. The results of this study indicate that the prevalence of Salmonella in individual fecal samples was less than 10%, but that Salmonella is widely distributed among feedlot cattle. Furthermore, when Salmonella is present in feedlot cattle, there is a low occurrence of antimicrobial resistance with the exception of tetracycline and sulfisoxazole. More research is indicated to understand the ecology of Salmonella and antimicrobial resistance, when present, in cattle-feeding operations.

  9. Prevalence and Antimicrobial Resistance of Salmonella Isolated from Cattle Feces in United States Feedlots in 2011.

    PubMed

    Dargatz, David A; Kopral, Christine A; Erdman, Matthew M; Fedorka-Cray, Paula J

    2016-09-01

    The objective of this study was to determine the prevalence and characteristics of Salmonella spp. isolated from feces of cattle in feedlots in the United States. Fecal samples were collected from up to three pens of cattle in each of 68 feedlots in 12 states. Samples included up to 25 individual fecal pats from the pen floors and up to five composite samples from the floors of the same pens. The prevalence of Salmonella-positive samples was 9.1% (460/5050) and 11.3% (114/1009) for individual and composite samples, respectively. The prevalences of Salmonella at the pen level were 35.6% (72/202) and 22.8% (46/202) for individual and composite samples, respectively. Dietary factors, including inclusion of cottonseed hulls, coccidiostats, and antimicrobial drugs, were associated with differences in prevalence of Salmonella isolation. Overall, 32 serotypes of Salmonella were identified, but six serotypes accounted for 69.1% (495/716) of the isolates. Nearly two-thirds (64.7%, 44/68) of feedlots had at least one positive sample. All isolates were evaluated for susceptibility to a panel of 15 antimicrobial drugs. Most isolates (74.4%, 533/716) were susceptible to all antimicrobial drugs in the panel. When resistance was detected, it was most commonly to tetracycline (21.7%, 155/716 of isolates) or sulfisoxazole (12.4%, 89/716 of isolates). Less than 10% of the isolates were resistant to any other antimicrobials in the panel. The results of this study indicate that the prevalence of Salmonella in individual fecal samples was less than 10%, but that Salmonella is widely distributed among feedlot cattle. Furthermore, when Salmonella is present in feedlot cattle, there is a low occurrence of antimicrobial resistance with the exception of tetracycline and sulfisoxazole. More research is indicated to understand the ecology of Salmonella and antimicrobial resistance, when present, in cattle-feeding operations. PMID:27464334

  10. Prevalence and Antimicrobial Resistance in Escherichia coli from Food Animals in Lagos, Nigeria.

    PubMed

    Adenipekun, Eyitayo O; Jackson, Charlene R; Oluwadun, Afolabi; Iwalokun, Bamidele A; Frye, Jonathan G; Barrett, John B; Hiott, Lari M; Woodley, Tiffanie A

    2015-06-01

    Foodborne bacteria are often associated with human infections; these infections can become more complicated to treat if the bacteria are also resistant to antimicrobials. In this study, prevalence, antimicrobial resistance, and genetic relatedness of Escherichia coli among food producing animals from Lagos, Nigeria, was investigated. From December 2012 to June 2013, E. coli were isolated from fecal samples of healthy cattle, chicken, and swine. Antimicrobial susceptibility testing against 22 antimicrobials was performed using broth microdilution with the Sensititre™ system. Clonal types were determined by pulsed-field gel electrophoresis (PFGE). From the analysis, 211/238 (88.7%), 170/210 (81%), and 136/152 (89.5%) samples from cattle, chicken, and swine, respectively, were positive for E. coli. A subset of those isolates (n=211) selected based on β-lactamase production was chosen for further study. Overall, E. coli exhibited the highest resistance to tetracycline (124/211; 58.8%), trimethoprim/sulfamethoxazole (84/211; 39.8%), and ampicillin (72/211; 34.1%). Approximately 40% of the isolates were pan-susceptible, and none of the isolates were resistant to amikacin, cefepime, ceftazidime, ertapenem, meropenem, or tigecycline. Among the resistant isolates, 28 different resistance patterns were observed; 26 of those were characterized as multi-drug resistant (MDR; resistance to ≥2 antimicrobials). One isolate was resistant to 13 different antimicrobials representing five different antimicrobial classes. Using PFGE, MDR E. coli were genetically diverse and overall did not group based on source; identical PFGE patterns were detected among isolates from different sources. These results suggest that isolates cannot be attributed to specific sources, and some may be present across all of the sources. Results from this study indicate that food-producing animals in Nigeria are a reservoir of MDR E. coli that may be transferred to humans via the food chain.

  11. Prevalence and Antimicrobial Resistance of Campylobacter Isolated from Dressed Beef Carcasses and Raw Milk in Tanzania.

    PubMed

    Kashoma, Isaac P; Kassem, Issmat I; John, Julius; Kessy, Beda M; Gebreyes, Wondwossen; Kazwala, Rudovick R; Rajashekara, Gireesh

    2016-01-01

    Campylobacter species are commonly transmitted to humans through consumption of contaminated foods such as milk and meat. The aim of this study was to investigate the prevalence, antimicrobial resistance, and genetic determinants of resistance of Campylobacter isolated from raw milk and beef carcasses in Tanzania. The antimicrobial resistance genes tested included blaOXA-61 (ampicillin), aph-3-1 (aminoglycoside), tet(O) (tetracycline), and cmeB (multi-drug efflux pump). The prevalence of Campylobacter was 9.5% in beef carcasses and 13.4% in raw milk, respectively. Using multiplex-polymerase chain reaction (PCR), we identified 58.1% of the isolates as Campylobacter jejuni, 30.7% as Campylobacter coli, and 9.7% as other Campylobacter spp. One isolate (1.6%) was positive for both C. jejuni and C. coli specific PCR. Antimicrobial susceptibility testing using the disk diffusion assay and the broth microdilution method showed resistance to: ampicillin (63% and 94.1%), ciprofloxacin (9.3% and 11.8%), erythromycin (53.7% and 70.6%), gentamicin (0% and 15.7%), streptomycin (35.2% and 84.3%), and tetracycline (18.5% and 17.7%), respectively. Resistance to azithromycin (42.6%), nalidixic acid (64.8%), and chloramphenicol (13%) was determined using the disk diffusion assay only, while resistance to tylosin (90.2%) was quantified using the broth microdilution method. The blaOXA-61 (52.6% and 28.1%), cmeB (26.3% and 31.3%), tet(O) (26.3% and 31.3%), and aph-3-1 (5.3% and 3.0%) were detected in C. coli and C. jejuni. These findings highlight the extent of antimicrobial resistance in Campylobacter occurring in important foods in Tanzania. The potential risks to consumers emphasize the need for adequate control approaches, including the prudent use of antimicrobials to minimize the spread of antimicrobial-resistant Campylobacter.

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

    PubMed Central

    Jia, Wei; Li, Gang; Wang, Wen

    2014-01-01

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

  13. Prevalence, characteristics, and antimicrobial resistance patterns of Salmonella in retail pork in Jiangsu province, eastern China.

    PubMed

    Li, Yu-Chen; Pan, Zhi-Ming; Kang, Xi-Long; Geng, Shi-Zhong; Liu, Zhong-Yi; Cai, Yin-Qiang; Jiao, Xin-An

    2014-02-01

    Salmonella is commonly isolated from raw pork and is a leading cause of foodborne illness. Because China has the highest rate of pork consumption and the largest number of pig breeding facilities in the world, an epidemiological analysis of Salmonella species from pork in China is warranted. In this study, pork samples (n = 1,096) were collected from 20 major free markets in four cities of Jiangsu province from August 2010 to December 2012. A total of 163 Salmonella isolates were recovered from 154 Salmonella-positive samples. Among 14 Salmonella serovars identified, Derby (47.9%) was most prevalent, followed by Typhimurium (10.4%), Meleagridis (9.2%), Anatum (8.6%), and London (6.7%). Antimicrobial sensitivity testing revealed that 134 (82.2%) of the isolates were resistant to at least one antimicrobial agent, and 41 (25.2%) were resistant to more than three antimicrobials. The highest resistance was to tetracycline (66.3% of isolates) followed by ampicillin (39.9%), trimethoprim-sulfamethoxazole (31.3%), and nalidixic acid (30.1%). Multilocus sequence typing analysis revealed 14 sequence type (ST) patterns; ST40 was the most common (77 isolates) followed by ST64 (19 isolates). Our research revealed a high prevalence of Salmonella in retail pork. Diversity among the Salmonella isolates was high in terms of serovar and genotype, and multidrug resistance was prevalent. Multilocus sequence type was generally associated with serovar and provided a reliable prediction of the most common Salmonella serovars.

  14. The Prevalence, Genotype and Antimicrobial Susceptibility of High- and Low-Level Mupirocin Resistant Methicillin-Resistant Staphylococcus aureus

    PubMed Central

    Park, Se Young; Kim, Shin Moo

    2012-01-01

    Background Mupirocin has been used for the treatment of skin infections and eradication of nasal carriage of methicillin-resistant Staphylococcus aureus (MRSA). The increased use of this antibiotic has been accompanied by outbreaks of MRSA that are resistant to mupirocin. Objective This study aims to determine the prevalence, genotype and antimicrobial susceptibility of mupirocin-resistant MRSA from 4 Korean hospitals. Methods A total 193 MRSA clinical isolates were collected from four university hospitals. Antimicrobial susceptibility tests, including mupirocin, and pulsed-field gel electrophoresis (PFGE) pattern analysis were performed. Results Overall, 27 of the 193 (14.1%) MRSA isolates were resistant to mupirocin. All of the (A) hospital isolates showed high-level (HL) mupirocin resistance and the low-level (LL) mupirocin resistant strains were from three other hospitals. The PFGE patterns of 16 mupirocin-resistant isolates were divided into 5 clusters (1-5), and the nine HL mupirocin-resistant isolates belonged to cluster 1. Both the HL and LL mupirocin-resistant MRSA isolates were susceptible to vancomycin and rifampin, but they were resistant to ciprofloxacin, clindamycin and tetracycline. The erythromycin and fusidic acid resistance rates were different between the HL and LL resistant isolates. Conclusion HL mupirocin-resistant isolates that could transfer this resistance to other bacteria were detected and these isolates were clonally related. The emergence of mupirocin resistant isolates emphasizes the importance of using antibiotics judiciously and carefully monitoring the prevalence of mupirocin resistance. PMID:22363153

  15. Prevalence of antimicrobial resistance in Escherichia coli and Klebsiella spp. in rural South India.

    PubMed

    Sekar, Ramalingam; Mythreyee, Manoharan; Srivani, Seetharaman; Amudhan, Murugesan

    2016-06-01

    The emergence and dissemination of antimicrobial resistance (AMR) is an important public health problem as resistant organisms cause difficult-to-treat infections. In this study, the prevalence of AMR in Escherichia coli and Klebsiella spp. in rural South India was examined in order to aid empirical therapy. A cross-sectional prospective study was conducted during the period from January 2012 to December 2014. Routine clinical isolates of E. coli and Klebsiella spp. were tested for antimicrobial susceptibility to β-lactams, aminoglycosides, fluoroquinolones, tetracyclines, colistin and nitrofurantoin by the Kirby-Bauer disk diffusion method and the data were documented and analyzed with one per patient analysis using WHONET software. A total of 2292 non-duplicate clinical isolates were recovered during the study period, including 1338 E. coli and 954 Klebsiella spp. The prevalence of AMR in the total isolates was as follows: amikacin, 17.3%; ertapenem, 14.4%; doripenem, 4.5%; colistin, 13.2%; and tigecycline, 4.1%. The study results indicate a high prevalence of carbapenem resistance in Klebsiella spp. especially from pus and urinary isolates, whilst the prevalence of aztreonam and fluoroquinolone resistance was very high in E. coli. PMID:27436473

  16. Prevalence and Antimicrobial Resistance of Campylobacter Isolated from Dressed Beef Carcasses and Raw Milk in Tanzania.

    PubMed

    Kashoma, Isaac P; Kassem, Issmat I; John, Julius; Kessy, Beda M; Gebreyes, Wondwossen; Kazwala, Rudovick R; Rajashekara, Gireesh

    2016-01-01

    Campylobacter species are commonly transmitted to humans through consumption of contaminated foods such as milk and meat. The aim of this study was to investigate the prevalence, antimicrobial resistance, and genetic determinants of resistance of Campylobacter isolated from raw milk and beef carcasses in Tanzania. The antimicrobial resistance genes tested included blaOXA-61 (ampicillin), aph-3-1 (aminoglycoside), tet(O) (tetracycline), and cmeB (multi-drug efflux pump). The prevalence of Campylobacter was 9.5% in beef carcasses and 13.4% in raw milk, respectively. Using multiplex-polymerase chain reaction (PCR), we identified 58.1% of the isolates as Campylobacter jejuni, 30.7% as Campylobacter coli, and 9.7% as other Campylobacter spp. One isolate (1.6%) was positive for both C. jejuni and C. coli specific PCR. Antimicrobial susceptibility testing using the disk diffusion assay and the broth microdilution method showed resistance to: ampicillin (63% and 94.1%), ciprofloxacin (9.3% and 11.8%), erythromycin (53.7% and 70.6%), gentamicin (0% and 15.7%), streptomycin (35.2% and 84.3%), and tetracycline (18.5% and 17.7%), respectively. Resistance to azithromycin (42.6%), nalidixic acid (64.8%), and chloramphenicol (13%) was determined using the disk diffusion assay only, while resistance to tylosin (90.2%) was quantified using the broth microdilution method. The blaOXA-61 (52.6% and 28.1%), cmeB (26.3% and 31.3%), tet(O) (26.3% and 31.3%), and aph-3-1 (5.3% and 3.0%) were detected in C. coli and C. jejuni. These findings highlight the extent of antimicrobial resistance in Campylobacter occurring in important foods in Tanzania. The potential risks to consumers emphasize the need for adequate control approaches, including the prudent use of antimicrobials to minimize the spread of antimicrobial-resistant Campylobacter. PMID:26153978

  17. Antimicrobial Resistance

    MedlinePlus

    ... antibiotic are known as methicillin-resistant S. aureus or MRSA. Antibiotics and other antimicrobial drugs first became widely ... factors for infection are known as community-associated MRSA (CA-MRSA). Recently, several cases overseas and in ...

  18. Prevalence and antimicrobial resistance of Salmonella isolated from meat and meat products in Algiers (Algeria).

    PubMed

    Mezali, Lynda; Hamdi, Taha Mossadak

    2012-06-01

    This study was conducted in order to estimate the proportion of raw meat and processed meat products contaminated by Salmonella in the region of Algiers, Algeria, to identify serovars and to determine the antimicrobial resistance patterns of isolates. Out of the total 314 samples (144 of raw red meat and meat products, 128 of raw poultry meat and poultry products, and 42 of processed meat products) collected from various retail outlets, 61 (19.43%) were tested positive for Salmonella. The most significant occurrences were recorded for the categories of red meat (23.61%, n=34) and poultry (17.97%, n=23). Among the 64 isolates recovered, 21 different serovars were identified and two strains were nontypable. The most prevalent serovars were Salmonella Anatum (14.6%, n=9), Salmonella Altona (12.50%, n=8), Salmonella Corvallis (7.81%, n=5), Salmonella Enteritidis (7.81%, n=5), and Salmonella Typhimurium (7.81%, n=5). Sixty-two Salmonella isolates were tested for their susceptibility to 32 selected antimicrobial agents. Fifty-six (90.32%) isolates were resistant to at least one antimicrobial, of which 20 (32.26%) showed multidrug resistance. Resistance to sulphonamides (87.10%, n=54) was the most common. Resistance rates were lower to nalidixic acid (16.13%, n=10), streptomycin (16.13%, n=10), and tetracycline (12.90%, n=8), while resistance to pefloxacin was estimated at 4.84% (n=3). Fourteen different resistance patterns were observed. The "ACSSuT" pentaresistance pattern was observed in three of the Salmonella Typhimurium strains. The obtained results show that these foodstuffs are a potential source of antimicrobial-resistant Salmonella for human infections. PMID:22571639

  19. Prevalence of antimicrobial resistance of non-typhoidal Salmonella serovars in retail aquaculture products.

    PubMed

    Zhang, Jianmin; Yang, Xiaowei; Kuang, Dai; Shi, Xianming; Xiao, Wenjia; Zhang, Jing; Gu, Zhen; Xu, Xuebin; Meng, Jianghong

    2015-10-01

    Aquaculture products can become sources of Salmonella by exposure to contaminated water or through processing practices, thus representing a public health hazard. A study was conducted on Salmonella contamination in aquaculture products sampled from marketplaces and retailers in Shanghai, China. A total of 730 samples (including fish, shellfish, bullfrog, clam, shrimp and others) were obtained from 2006 to 2011. Among them, 217 (29.7%) were positive for Salmonella. Thirty-eight serovars were identified in the 217 Salmonella isolates. The most prevalent were Salmonella Aberdeen (18.4%), S. Wandsworth (12.0%), S. Thompson (9.2%), S. Singapore (5.5%), S. Stanley (4.6%), S. Schwarzengrund (4.6%), S. Hvittingfoss (4.1%) and S. Typhimurium (4.1%). Many resistant isolates were detected, with 69.6% resistant to at least one antimicrobial drug. We observed high resistance to sulfonamides (56.5%), tetracycline (34.1%), streptomycin (28.6%), ampicillin (23.5%) and nalidixic acid (21.2%). Lower levels of resistance were found for gentamicin (3.2%), ciprofloxacin (2.3%), ceftiofur (1.3%), cefotaxime (0.9%), ceftazidime (0.5%) and cefepime (0.5%). A total of 43.3% of the Salmonella isolates were multidrug-resistant and 44 different resistance patterns were found. This study provided data on the prevalence, serovars and antimicrobial resistance of Salmonella from retail aquaculture products in Shanghai, and indicated the need for monitoring programs for microbiologic safety in such projects and for more prudent drug use in aquaculture production in order to reduce the risk of development and spread of antimicrobial resistance.

  20. Determination of the prevalence of antimicrobial resistance genes in canine Clostridium perfringens isolates.

    PubMed

    Kather, Elizabeth J; Marks, Stanley L; Foley, Janet E

    2006-03-10

    Clostridium perfringens is a well documented cause of a mild self-limiting diarrhea and a potentially fatal acute hemorrhagic diarrheal syndrome in the dog. A recent study documented that 21% of canine C. perfringens isolates had MIC's indicative of resistance to tetracycline, an antimicrobial commonly recommended for treatment of C. perfringens-associated diarrhea. The objective of the present study was to further evaluate the antimicrobial susceptibility profiles of these isolates by determining the prevalence of specific resistance genes, their expression, and ability for transference between bacteria. One hundred and twenty-four canine C. perfringens isolates from 124 dogs were evaluated. Minimum inhibitory concentrations of tetracycline, erythromycin, tylosin, and metronidazole were determined using the CLSI Reference Agar Dilution Method. All isolates were screened for three tetracycline resistance genes: tetA(P), tetB(P) and tetM, and two macrolide resistance genes: ermB and ermQ, via PCR using primer sequences previously described. Ninety-six percent (119/124) of the isolates were positive for the tetA(P) gene, and 41% (51/124) were positive for both the tetA(P) and tetB(P) genes. No isolates were positive for the tetB(P) gene alone. Highly susceptible isolates (MIC< or = 4 microg/ml) were significantly more likely to lack the tetB(P) gene. One isolate (0.8%) was positive for the ermB gene, and one isolate was positive for the ermQ gene. The tetM gene was not found in any of the isolates tested. Two out of 15 tested isolates (13%) demonstrated transfer of tetracycline resistance via bacterial conjugation. Tetracycline should be avoided for the treatment of C. perfringens-associated diarrhea in dogs because of the relatively high prevalence of in vitro resistance, and the potential for conjugative transfer of antimicrobial resistance. PMID:16330169

  1. Prevalence of Antimicrobial Resistance in Escherichia coli Strains Isolated from Fishery Workers

    PubMed Central

    Shin, Hyun-Ho; Cho, Seung-Hak

    2013-01-01

    Objectives: This study aimed to characterize the prevalence of antibiotic resistance in Escherichia coli isolates from the fecal samples of fishery workers who work in fish farms and often use antibiotics for the feeding fishes. Methods: Seventy-three E. coli strains isolated from the fecal samples of fishery workers and 180 isolates from a control group of restaurant workers were tested for antibiotic resistance by agar disk diffusion with 16 antimicrobial agents. Results: About 30% of isolates from each group showed antimicrobial resistance to ampicillin, and 60% of isolates from fishery workers and 41% from restaurant workers were resistant to tetracycline. The isolates showed higher resistance to cephalothin and cefoxitin than to other cephem antibiotics and to gentamicin than to other aminogycosides. Our data indicated that fecal E. coli isolates from fishery workers showed higher antibiotic resistance than those of non-fishery workers (restaurant workers), especially to cephalothin, tetracycline, and trimethoprim–sulfamethoxazole (p < 0.05). However, rates of multidrug resistance were similar among the fishery workers and restaurant workers. Conclusion: Frequent use of antibiotics may cause increased antibiotic resistance in the human microbiome. PMID:24159534

  2. High Prevalence of Antimicrobial Resistance Among Common Bacterial Isolates in a Tertiary Healthcare Facility in Rwanda

    PubMed Central

    Ntirenganya, Cyprien; Manzi, Olivier; Muvunyi, Claude Mambo; Ogbuagu, Onyema

    2015-01-01

    Antimicrobial resistance (AMR) is a serious public health threat in both developed and developing countries. Many developing countries, including Rwanda, lack adequate surveillance systems, and therefore, the prevalence of AMR is not well-known. We conducted a prospective observational study to assess the prevalence of AMR among common bacterial isolates from clinical specimens obtained from patients on the medical wards of Kigali University Teaching Hospital (KUTH). We evaluated the antibiotic sensitivity patterns of bacterial pathogens cultured from urine, blood, sputum, and wound swab specimens obtained over a 6-month period (July 1 to December 30, 2013). There were 154 positive cultures from specimens obtained from 141 unique patients over the study period. Urine, blood, wound swab, and sputum cultures comprised 55.2%, 25.3%, 16.2%, and 3.3% of the total specimens evaluated; 31.4% and 58.7% of Escherichia coli and Klebsiella isolates, respectively, were resistant to at least one of the third generation cephalosporins. Eight percent of E. coli isolates were resistant to imipenem; 82% and 6% of Staphylococcus aureus strains were oxacillin- and vancomycin-resistant respectively. Antimicrobial resistance rates are high in Rwanda and pose a serious therapeutic challenge to the management of common infections. PMID:25646259

  3. Prevalence and Antimicrobial-Resistance of Pseudomonas aeruginosa in Swimming Pools and Hot Tubs

    PubMed Central

    Lutz, Jonathan K.; Lee, Jiyoung

    2011-01-01

    Pseudomonas aeruginosa is an important opportunistic pathogen in recreational waters and the primary cause of hot tub folliculitis and otitis externa. The aim of this surveillance study was to determine the background prevalence and antimicrobial resistance profile of P. aeruginosa in swimming pools and hot tubs. A convenience sample of 108 samples was obtained from three hot tubs and eight indoor swimming pools. Water and swab samples were processed using membrane filtration, followed by confirmation with polymerase chain reaction. Twenty-three samples (21%) were positive for P. aeruginosa, and 23 isolates underwent susceptibility testing using the microdilution method. Resistance was noted to several antibiotic agents, including amikacin (intermediate), aztreonam, ceftriaxone, gentamicin, imipenem, meropenem (intermediate), ticarcillin/clavulanic acid, tobramycin (intermediate), and trimethoprim/sulfamethoxazole. The results of this surveillance study indicate that 96% of P. aeruginosa isolates tested from swimming pools and hot tubs were multidrug resistant. These results may have important implications for cystic fibrosis patients and other immune-suppressed individuals, for whom infection with multidrug-resistant P. aeruginosa would have greater impact. Our results underlie the importance of rigorous facility maintenance, and provide prevalence data on the occurrence of antimicrobial resistant strains of this important recreational water-associated and nosocomial pathogen. PMID:21556203

  4. High prevalence of antimicrobial resistance among common bacterial isolates in a tertiary healthcare facility in Rwanda.

    PubMed

    Ntirenganya, Cyprien; Manzi, Olivier; Muvunyi, Claude Mambo; Ogbuagu, Onyema

    2015-04-01

    Antimicrobial resistance (AMR) is a serious public health threat in both developed and developing countries. Many developing countries, including Rwanda, lack adequate surveillance systems, and therefore, the prevalence of AMR is not well-known. We conducted a prospective observational study to assess the prevalence of AMR among common bacterial isolates from clinical specimens obtained from patients on the medical wards of Kigali University Teaching Hospital (KUTH). We evaluated the antibiotic sensitivity patterns of bacterial pathogens cultured from urine, blood, sputum, and wound swab specimens obtained over a 6-month period (July 1 to December 30, 2013). There were 154 positive cultures from specimens obtained from 141 unique patients over the study period. Urine, blood, wound swab, and sputum cultures comprised 55.2%, 25.3%, 16.2%, and 3.3% of the total specimens evaluated; 31.4% and 58.7% of Escherichia coli and Klebsiella isolates, respectively, were resistant to at least one of the third generation cephalosporins. Eight percent of E. coli isolates were resistant to imipenem; 82% and 6% of Staphylococcus aureus strains were oxacillin- and vancomycin-resistant respectively. Antimicrobial resistance rates are high in Rwanda and pose a serious therapeutic challenge to the management of common infections.

  5. Effect of farm type on within-herd Salmonella prevalence, serovar distribution, and antimicrobial resistance.

    PubMed

    Rasschaert, G; Michiels, J; Arijs, D; Wildemauwe, C; De Smet, S; Heyndrickx, M

    2012-05-01

    Salmonella represents a major challenge to the pig industry, as pork presents a risk for human salmonellosis. In this study, we have examined the effect of farm type on the prevalence of fattening pigs shedding Salmonella on 12 farms at risk for harboring Salmonella. On six open (grow-to-finish) and six closed (farrow-to-finish) farms, the prevalence of pigs shedding Salmonella was determined on two occasions approximately 2 months apart. The serovar, phage type, and antimicrobial resistance of the obtained Salmonella isolates were determined. On all farms, pigs shedding Salmonella were detected on at least one of the two sampling days. The mean within-herd prevalence was 7.8%. Closed farms were two times less likely to have pigs shedding Salmonella than open farms. On open farms, the odds of finding Salmonella shedding in pigs were 1.9 times higher when sampling was performed at slaughter age than when samples were taken halfway through the fattening period. Salmonella enterica serovar Typhimurium was the most predominant serotype, with a prevalence of 62 to 63% on both farm types. Of all the Salmonella Typhimurium isolates, 65% had the tetraresistant profile ASSuT (ampicillin, streptomycin, sulfonamide, and tetracycline) with or without additional resistance to trimethoprim-sulfonamide. Phage type DT120 seemed to be especially associated with this antimicrobial-resistant profile. The prevalence of Salmonella Typhimurium isolates showing resistance to ampicillin, streptomycin, tetracycline, sulfonamide, trimethoprim-sulfonamide, and lincomycin hydrochloride and spectinomycin sulfate tetrahydrate was significantly higher on open farms than on closed farms.

  6. Prevalence and antimicrobial resistance of listeria species isolated from different types of raw meat in Iran.

    PubMed

    Rahimi, Ebrahim; Yazdi, Farzad; Farzinezhadizadeh, Hussein

    2012-12-01

    Listeria and particularly Listeria monocytogenes are important foodborne pathogens that can cause listeriosis and severe complications in immunocompromised individuals, children, pregnant women, and the elderly. The objective of this study was to determine the prevalence of Listeria spp. in raw meat in Iran. From July 2010 to November 2011, a total of 1,107 samples of various raw meats were obtained from randomly selected retail butcher shops. The results of conventional bacteriologic and PCR methods revealed that 141 samples (12.7%) were positive for Listeria spp. The highest prevalence of Listeria was found in raw buffalo meat samples (7 of 24 samples; 29.2%) followed by quail meat (26 of 116 samples; 22.4%), partridge meat (13 of 74 samples; 17.6%), and chicken meat (27 of 160 samples; 16.9%). The most common species recovered was Listeria innocua (98 of 141 strains; 75.9 % ); the remaining isolates were L. monocytogenes (19.1% of strains), Listeria welshimeri (6.4% of strains), Listeria seeligeri (3.5% of strains), and Listeria grayi (1.4% of strains). Susceptibilities of the 141 strains to 11 antimicrobial drugs were determined using the disk diffusion assay. Overall, 104 (73.8%) of the Listeria isolates were resistant to one or more antimicrobials, and 17.0% of the isolates were resistant to three or more antimicrobials. The present study provides the first baseline data on the prevalence of Listeria in raw meat derived from sheep, goat, buffalo, quail, partridge, chicken, and ostrich in Iran and the susceptibility of these isolates to antimicrobials.

  7. Prevalence and antimicrobial resistance of Vibrio spp. in retail shrimps in Vietnam.

    PubMed

    Tra, Vu Thi Thu; Meng, Lu; Pichpol, Duangporn; Pham, Ngan Hong; Baumann, Maximilian; Alter, Thomas; Huehn, Stephan

    2016-01-01

    The aim of the study was to investigate the prevalence and the antimicrobial resistance patterns of Vibrio (V.) spp. isolated from retail shrimp in Hanoi, Vietnam A total of 202 shrimp samples were collected from retail markets located in ten urban districts of Hanoi. Among those, 201 (99.5%) samples were positive for Vibrio spp. The most common species detected was V parahaemolyticus (96.5%), followed by V. alginolyticus (56.4%), V. cholerae (2%) and V. vulnificus (1.5%). Multiple Vibrio spp. were found in 114 (56.4%) samples. None of the V. parahaemolyticus isolates carried the virulence-associated tdh (thermostable direct haemolysin) and trh (tdh-related haemolysin) genes. In total, 195 V. parahaemolyticus isolates, four V. cholerae isolates and three V. vulnificus isolates were tested for resistance to eight antimicrobial agents. V. parahaemolyticus isolates showed high rates of resistance against ampicillin (87.2%), while a moderate rate was observed for sulfamethoxazole/trimethoprim (18.5%) and intermediate resistance towards tetracycline (24.6%). Low resistance rates (0.5%) were recorded against both ciprofloxacin and cefalothin. Only one V. cholerae isolate with resistance to ampicillin and two V. cholerae isolates with resistance to sulfamethoxazole/trimethoprim were found. All V. vulnificus isolates were susceptible to the eight antimicrobial agents tested. However, the number of V. vulnificus and V. cholerae was small. Multi-resistant isolates were found in V. parahaemolyticus with a low frequency (16.9%). The results of this study revealed the ubiquitous nature of Vibrio spp. in shrimp at retail. To reduce the potential risk of Vibrio infections due to handling or consumption of undercooked seafood, good manufacturing practice as well as safe handling and processing should be encouraged. PMID:26904896

  8. Prevalence and antimicrobial resistance of Arcobacter species isolated from poultry meat in Iran.

    PubMed

    Rahimi, Ebrahim

    2014-01-01

    1. The objective of this study was to determine the prevalence and antimicrobial resistance of Arcobacter spp. isolated from different species of retail poultry meat in Iran. 2. From August 2012 to April 2013, a total of 540 raw poultry meat samples from chicken (n = 100), turkey (n = 100), quail (n = 100), partridge (n = 80), duck (n = 50), ostrich (n = 60) and geese (n = 50) were purchased from randomly selected retail outlets in Shahrekord, Isfahan, Sari and Rasht, Iran. 3. Using culture techniques, 71 of 540 poultry meat samples (13.1%) were positive for Arcobacter spp. The highest prevalence of Arcobacter spp. was found in chicken meat (28.0%), followed by quail (12.0%), duck (11.4%), turkey (11.0%), geese (8.0%), partridge (7.5%) and ostrich (3.3%) meat. The number of A. butzleri isolated from poultry meat samples (90.1%) was significantly higher than A. cryaerophilus (7.1%) and A. skirrowii (2.8%). Significantly more poultry meat samples were found to contain Arcobacter spp. by the PCR assay than by the culture method. 4. Susceptibilities of Arcobacter isolates were determined for 14 antimicrobial drugs using the disk diffusion method. All of the 71 Arcobacter isolates tested were resistant to one or more antimicrobial agents. Resistance to cephalothin and vancomycin (95.8%) was the most common finding, followed by resistance to methicillin, azithromycin and ampicillin. All Arcobacter isolates were susceptible to gentamicin, streptomycin, tetracyclin and kanamycin. 5. The results of this study indicated the importance of poultry meat, especially chicken meat, as potential sources of Arcobacter spp. infection in people. Furthermore, the strains indicated resistance to a broad spectrum of antibiotics.

  9. Prevalence and antimicrobial resistance among Campylobacter spp. in Louisiana retail chickens after the enrofloxacin ban.

    PubMed

    Han, Feifei; Lestari, Shofiyah Ika; Pu, Shuaihua; Ge, Beilei

    2009-03-01

    Effective in September 2005, enrofloxacin, a fluoroquinolone group antimicrobial, was withdrawn from use in the U.S. poultry farms. In this 1-year study initiated in October 2006, we isolated and characterized Campylobacter spp. from Louisiana retail conventionally raised (n = 141) and organic (n = 53) chickens as a comparison to evaluate the postban bacterial resistance to antimicrobials. Campylobacter was present in 43.3% of the chickens; similar rates were observed among conventional and organic chickens. A total of 165 Campylobacter isolates were recovered, with Campylobacter jejuni being the predominant species (66.7%). No apparent seasonal trend was deduced from the prevalence data. Further, the two main conventional and one organic chicken brands did not carry significantly different rates of Campylobacter (p > 0.05). The most common resistance observed was to tetracycline (31.5%), followed by erythromycin (20%) and ciprofloxacin (6.1%). No resistance to gentamicin was identified. All Campylobacter isolates recovered from organic chickens (n = 48) were susceptible to ciprofloxacin, compared to 8.5% resistance rate for those from conventional chickens (n = 117). Additionally, the resistance rate to erythromycin was significantly higher in Campylobacter isolates from conventional chickens (23.9%) than those from organic chickens (10.4%; p < 0.05). Our results demonstrated a low prevalence and low ciprofloxacin resistance rate of Campylobacter in Louisiana retail chickens after the enrofloxacin ban. Further studies involving a larger sample size over time are warranted to better assess the effects of banning enrofloxacin use in poultry and the levels of fluoroquinolone-resistant Campylobacter. PMID:19099357

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

    PubMed

    Sperling, L; Alter, T; Huehn, S

    2015-11-01

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

  11. Prevalence and genetic relatedness of antimicrobial-resistant Escherichia coli isolated from animals, foods and humans in Iceland.

    PubMed

    Thorsteinsdottir, T R; Haraldsson, G; Fridriksdottir, V; Kristinsson, K G; Gunnarsson, E

    2010-05-01

    The prevalence of resistant bacteria in food products in Iceland is unknown, and little is known of the prevalence in production animals. The aim of this study was to investigate the prevalence and genetic relatedness of antimicrobial-resistant Escherichia coli from healthy pigs and broiler chicken, pork, broiler meat, slaughterhouse personnel and outpatients in Iceland. A total of 419 E. coli isolates were tested for antimicrobial susceptibility using a microbroth dilution method (VetMIC), and resistant strains were compared using pulsed-field gel electrophoresis (PFGE). All samples were screened for enrofloxacin-resistant strains with selective agar plates. The resistance rates among E. coli isolates were moderate to high from caecal and meat samples of pigs (54.1% and 28%), broilers (33.6% and 52%) and slaughterhouse personnel (39.1%), whereas isolates from outpatients showed moderate resistance rates (23.1%). Of notice was resistance to quinolones (minimum inhibitory concentrations: nalidixic acid > or = 32, ciprofloxacin > or = 0.12 and enrofloxacin > or = 0.5), particularly among broiler and broiler meat isolates (18.2% and 36%), as there is no known antimicrobial selection pressure in the broiler production in Iceland. The majority (78.6%) of the resistant E. coli isolates was genotypically different, based on PFGE fingerprint analyses and clustering was limited. However, the same resistance pattern and pulsotype were found among isolates from broiler meat and a slaughterhouse worker, indicating spread of antimicrobial-resistant E. coli from animals to humans. Diverse resistance patterns and pulsotypes suggest the presence of a large population of resistant E. coli in production animals in Iceland. This study gives baseline information on the prevalence of antimicrobial-resistant E. coli from production animals, and their food products in Iceland and the moderate to high resistance rates emphasize the need for continuing surveillance. Further studies on the

  12. Prevalence, virulence and antimicrobial resistance patterns of Aeromonas spp. isolated from children with diarrhea

    PubMed Central

    Soltan Dallal, Mohammad Mehdi; Mazaheri Nezhad Fard, Ramin; Kavan Talkhabi, Morteza; Aghaiyan, Leyla; Salehipour, Zohre

    2016-01-01

    Background Aeromonas spp. cause various intestinal and extraintestinal diseases. These bacteria are usually isolated from fecal samples, especially in children under five years old. The aim of this study was to assess the prevalence of Aeromonas spp. and their antimicrobial resistance profile in children with diarrhea referred to the Children Medical Center in Tehran, between 2013 and 2014. Methods A total number of 391 stool samples were collected from children with ages between 1 day and 14 years old, with diarrhea (acute or chronic), referred to the Children Hospital, Tehran, Iran, between 2013 and 2014. Samples were enriched in alkaline peptone water broth for 24 hours at 37 °C and then cultured. Suspicious colonies were analyzed through biochemical tests. Furthermore, antimicrobial susceptibility tests were carried out for the isolates. Isolates were further studied for act, ast, alt, aerA and hlyA virulence genes using polymerase chain reaction. Results In total, 12 isolates (3.1%) were identified as Aeromonas spp.; all were confirmed using the API-20E test. Of these isolates, five A. caviae (42%), four A. veronii (33%) and three A. hydrophila (25%) were identified in cases with gastroenteritis. Second to ampicillin (which was included in the growth medium used), the highest rate of antimicrobial resistance was seen against nalidixic acid and trimethoprim-sulfamethoxazole (5 isolates each, 41.6%) and the lowest rate of antimicrobial resistance was seen against gentamicin, amikacin and cefepime (none of the isolates). Results included 76.4% act, 64.7% ast, 71.5% alt, 83.3% aerA and 11.7% hlyA genes. Conclusion Aeromonas spp. are important due to their role in diarrhea in children; therefore, isolation and identification of these fecal pathogens should seriously be considered in medical laboratories. Since virulence genes play a significant role in gastroenteritis symptoms caused by these bacteria, Aeromonas species that include virulence genes are potentially

  13. Prevalence, virulence and antimicrobial resistance patterns of Aeromonas spp. isolated from children with diarrhea

    PubMed Central

    Soltan Dallal, Mohammad Mehdi; Mazaheri Nezhad Fard, Ramin; Kavan Talkhabi, Morteza; Aghaiyan, Leyla; Salehipour, Zohre

    2016-01-01

    Background Aeromonas spp. cause various intestinal and extraintestinal diseases. These bacteria are usually isolated from fecal samples, especially in children under five years old. The aim of this study was to assess the prevalence of Aeromonas spp. and their antimicrobial resistance profile in children with diarrhea referred to the Children Medical Center in Tehran, between 2013 and 2014. Methods A total number of 391 stool samples were collected from children with ages between 1 day and 14 years old, with diarrhea (acute or chronic), referred to the Children Hospital, Tehran, Iran, between 2013 and 2014. Samples were enriched in alkaline peptone water broth for 24 hours at 37 °C and then cultured. Suspicious colonies were analyzed through biochemical tests. Furthermore, antimicrobial susceptibility tests were carried out for the isolates. Isolates were further studied for act, ast, alt, aerA and hlyA virulence genes using polymerase chain reaction. Results In total, 12 isolates (3.1%) were identified as Aeromonas spp.; all were confirmed using the API-20E test. Of these isolates, five A. caviae (42%), four A. veronii (33%) and three A. hydrophila (25%) were identified in cases with gastroenteritis. Second to ampicillin (which was included in the growth medium used), the highest rate of antimicrobial resistance was seen against nalidixic acid and trimethoprim-sulfamethoxazole (5 isolates each, 41.6%) and the lowest rate of antimicrobial resistance was seen against gentamicin, amikacin and cefepime (none of the isolates). Results included 76.4% act, 64.7% ast, 71.5% alt, 83.3% aerA and 11.7% hlyA genes. Conclusion Aeromonas spp. are important due to their role in diarrhea in children; therefore, isolation and identification of these fecal pathogens should seriously be considered in medical laboratories. Since virulence genes play a significant role in gastroenteritis symptoms caused by these bacteria, Aeromonas species that include virulence genes are potentially

  14. Prevalence and antimicrobial resistance of Listeria, Salmonella, and Yersinia species isolates in ducks and geese.

    PubMed

    Jamali, Hossein; Radmehr, Behrad; Ismail, Salmah

    2014-04-01

    The aims of this study were to determine the prevalence and antimicrobial resistance of Listeria, Salmonella, and Yersinia spp. isolated from duck and goose intestinal contents. A total of 471 samples, including 291 duck and 180 goose intestinal contents, were purchased from wet markets between November 2008 and July 2010. Listeria, Salmonella, and Yersinia spp. were isolated from 58 (12.3%), 107 (22.7%), and 80 (17%) of the samples, respectively. It was concluded that Listeria ivanovii, Salmonella Thompson, and Yersinia enterocolitica were the predominant serovars among Listeria, Salmonella, and Yersinia spp., respectively. Moreover, resistance to tetracycline was common in Listeria (48.3%) and Salmonella spp. (63.6%), whereas 51.3% of the Yersinia spp. isolates were resistant to cephalothin. Therefore, continued surveillance of the prevalence of the pathogens and also of emerging antibiotic resistance is needed to render possible the recognition of foods that may represent risks and also ensure the effective treatment of listeriosis, salmonellosis, and yersiniosis.

  15. Predicting Antimicrobial Resistance Prevalence and Incidence from Indicators of Antimicrobial Use: What Is the Most Accurate Indicator for Surveillance in Intensive Care Units?

    PubMed Central

    Fortin, Élise; Platt, Robert W.; Fontela, Patricia S.; Buckeridge, David L.; Quach, Caroline

    2015-01-01

    Objective The optimal way to measure antimicrobial use in hospital populations, as a complement to surveillance of resistance is still unclear. Using respiratory isolates and antimicrobial prescriptions of nine intensive care units (ICUs), this study aimed to identify the indicator of antimicrobial use that predicted prevalence and incidence rates of resistance with the best accuracy. Methods Retrospective cohort study including all patients admitted to three neonatal (NICU), two pediatric (PICU) and four adult ICUs between April 2006 and March 2010. Ten different resistance / antimicrobial use combinations were studied. After adjustment for ICU type, indicators of antimicrobial use were successively tested in regression models, to predict resistance prevalence and incidence rates, per 4-week time period, per ICU. Binomial regression and Poisson regression were used to model prevalence and incidence rates, respectively. Multiplicative and additive models were tested, as well as no time lag and a one 4-week-period time lag. For each model, the mean absolute error (MAE) in prediction of resistance was computed. The most accurate indicator was compared to other indicators using t-tests. Results Results for all indicators were equivalent, except for 1/20 scenarios studied. In this scenario, where prevalence of carbapenem-resistant Pseudomonas sp. was predicted with carbapenem use, recommended daily doses per 100 admissions were less accurate than courses per 100 patient-days (p = 0.0006). Conclusions A single best indicator to predict antimicrobial resistance might not exist. Feasibility considerations such as ease of computation or potential external comparisons could be decisive in the choice of an indicator for surveillance of healthcare antimicrobial use. PMID:26710322

  16. Prevalence, antimicrobial resistance and genetic diversity of Yersinia enterocolitica isolated from retail frozen foods in China.

    PubMed

    Ye, Qinghua; Wu, Qingping; Hu, Huijuan; Zhang, Jumei; Huang, Huixian

    2015-12-01

    In this study, our aim was to estimate the extent of Yersinia enterocolitica contamination in frozen foods in China and determine the bioserotype, virulotype, antimicrobial resistance, and enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) genotyping profiles of recovered Y. enterocolitica isolates. Out of 455 samples collected between July 2011 and May 2014, 56 (12.3%) tested positive for Y. enterocolitica. The 70 isolated strains were grouped into five clusters and one singleton based on their ERIC-PCR fingerprint, at a similarity coefficient of 70%. All strains were of biotype 1A, and 35.7% were of bioserotype 1A/O:8. Most strains lacked the virulence genes ail, virF, ystA, and ystC, but harbored ystB, fepD, ymoA, fes and sat. All strains were sensitive to ticarcillin but resistant to two or more antibiotics, and 48.6% of the strains were resistant to four to nine antibiotics. High resistance rates were observed for ampicillin, cephalothin, trimethoprim/sulfamethoxazole, amoxicillin/clavulanic acid, nalidixic acid and chloramphenicol (98.6%, 95.7%, 74.3%, 28.6%, 18.6% and 12.9%, respectively). This study provides a systematic surveillance of Y. enterocolitica prevalence in frozen foods in China and indicates its high antibiotic resistance, which could serve as useful information for the government to control Y. enterocolitica contamination in frozen foods and the use of antibiotics.

  17. Prevalence, antimicrobial resistance and genetic diversity of Yersinia enterocolitica isolated from retail frozen foods in China.

    PubMed

    Ye, Qinghua; Wu, Qingping; Hu, Huijuan; Zhang, Jumei; Huang, Huixian

    2015-12-01

    In this study, our aim was to estimate the extent of Yersinia enterocolitica contamination in frozen foods in China and determine the bioserotype, virulotype, antimicrobial resistance, and enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) genotyping profiles of recovered Y. enterocolitica isolates. Out of 455 samples collected between July 2011 and May 2014, 56 (12.3%) tested positive for Y. enterocolitica. The 70 isolated strains were grouped into five clusters and one singleton based on their ERIC-PCR fingerprint, at a similarity coefficient of 70%. All strains were of biotype 1A, and 35.7% were of bioserotype 1A/O:8. Most strains lacked the virulence genes ail, virF, ystA, and ystC, but harbored ystB, fepD, ymoA, fes and sat. All strains were sensitive to ticarcillin but resistant to two or more antibiotics, and 48.6% of the strains were resistant to four to nine antibiotics. High resistance rates were observed for ampicillin, cephalothin, trimethoprim/sulfamethoxazole, amoxicillin/clavulanic acid, nalidixic acid and chloramphenicol (98.6%, 95.7%, 74.3%, 28.6%, 18.6% and 12.9%, respectively). This study provides a systematic surveillance of Y. enterocolitica prevalence in frozen foods in China and indicates its high antibiotic resistance, which could serve as useful information for the government to control Y. enterocolitica contamination in frozen foods and the use of antibiotics. PMID:26472688

  18. Prevalence of Antimicrobial Resistance and Transfer of Tetracycline Resistance Genes in Escherichia coli Isolates from Beef Cattle

    PubMed Central

    Shin, Seung Won; Shin, Min Kyoung; Jung, Myunghwan; Belaynehe, Kuastros Mekonnen

    2015-01-01

    The aim of this study was to investigate the prevalence and transferability of resistance in tetracycline-resistant Escherichia coli isolates recovered from beef cattle in South Korea. A total of 155 E. coli isolates were collected from feces in South Korea, and 146 were confirmed to be resistant to tetracycline. The tetracycline resistance gene tet(A) (46.5%) was the most prevalent, followed by tet(B) (45.1%) and tet(C) (5.8%). Strains carrying tet(A) plus tet(B) and tet(B) plus tet(C) were detected in two isolates each. In terms of phylogenetic grouping, 101 (65.2%) isolates were classified as phylogenetic group B1, followed in decreasing order by D (17.4%), A (14.2%), and B2 (3.2%). Ninety-one (62.3%) isolates were determined to be multidrug resistant by the disk diffusion method. MIC testing using the principal tetracyclines, namely, tetracycline, chlortetracycline, oxytetracycline, doxycycline, and minocycline, revealed that isolates carrying tet(B) had higher MIC values than isolates carrying tet(A). Conjugation assays showed that 121 (82.9%) isolates could transfer a tetracycline resistance gene to a recipient via the IncFIB replicon (65.1%). This study suggests that the high prevalence of tetracycline-resistant E. coli isolates in beef cattle is due to the transferability of tetracycline resistance genes between E. coli populations which have survived the selective pressure caused by the use of antimicrobial agents. PMID:26048929

  19. Prevalence of Antimicrobial Resistance and Transfer of Tetracycline Resistance Genes in Escherichia coli Isolates from Beef Cattle.

    PubMed

    Shin, Seung Won; Shin, Min Kyoung; Jung, Myunghwan; Belaynehe, Kuastros Mekonnen; Yoo, Han Sang

    2015-08-15

    The aim of this study was to investigate the prevalence and transferability of resistance in tetracycline-resistant Escherichia coli isolates recovered from beef cattle in South Korea. A total of 155 E. coli isolates were collected from feces in South Korea, and 146 were confirmed to be resistant to tetracycline. The tetracycline resistance gene tet(A) (46.5%) was the most prevalent, followed by tet(B) (45.1%) and tet(C) (5.8%). Strains carrying tet(A) plus tet(B) and tet(B) plus tet(C) were detected in two isolates each. In terms of phylogenetic grouping, 101 (65.2%) isolates were classified as phylogenetic group B1, followed in decreasing order by D (17.4%), A (14.2%), and B2 (3.2%). Ninety-one (62.3%) isolates were determined to be multidrug resistant by the disk diffusion method. MIC testing using the principal tetracyclines, namely, tetracycline, chlortetracycline, oxytetracycline, doxycycline, and minocycline, revealed that isolates carrying tet(B) had higher MIC values than isolates carrying tet(A). Conjugation assays showed that 121 (82.9%) isolates could transfer a tetracycline resistance gene to a recipient via the IncFIB replicon (65.1%). This study suggests that the high prevalence of tetracycline-resistant E. coli isolates in beef cattle is due to the transferability of tetracycline resistance genes between E. coli populations which have survived the selective pressure caused by the use of antimicrobial agents.

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

    PubMed

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

    2015-01-01

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

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

    PubMed

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

    2016-02-01

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

  2. Animation of Antimicrobial Resistance

    MedlinePlus

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

  3. Prevalence of virulence determinants and antimicrobial resistance among commensal Escherichia coli derived from dairy and beef cattle.

    PubMed

    Bok, Ewa; Mazurek, Justyna; Stosik, Michał; Wojciech, Magdalena; Baldy-Chudzik, Katarzyna

    2015-01-01

    Cattle is a reservoir of potentially pathogenic E. coli, bacteria that can represent a significant threat to public health, hence it is crucial to monitor the prevalence of the genetic determinants of virulence and antimicrobial resistance among the E. coli population. The aim of this study was the analysis of the phylogenetic structure, distribution of virulence factors (VFs) and prevalence of antimicrobial resistance among E. coli isolated from two groups of healthy cattle: 50 cows housed in the conventional barn (147 isolates) and 42 cows living on the ecological pasture (118 isolates). The phylogenetic analysis, identification of VFs and antimicrobial resistance genes were based on either multiplex or simplex PCR. The antimicrobial susceptibilities of E. coli were examined using the broth microdilution method. Two statistical approaches were used to analyse the results obtained for two groups of cattle. The relations between the dependent (VFs profiles, antibiotics) and the independent variables were described using the two models. The mixed logit model was used to characterise the prevalence of the analysed factors in the sets of isolates. The univariate logistic regression model was used to characterise the prevalence of these factors in particular animals. Given each model, the odds ratio (OR) and the 95% confidence interval for the population were estimated. The phylogroup B1 was predominant among isolates from beef cattle, while the phylogroups A, B1 and D occurred with equal frequency among isolates from dairy cattle. The frequency of VFs-positive isolates was significantly higher among isolates from beef cattle. E. coli from dairy cattle revealed significantly higher resistance to antibiotics. Some of the tested resistance genes were present among isolates from dairy cattle. Our study showed that the habitat and diet may affect the genetic diversity of commensal E. coli in the cattle. The results suggest that the ecological pasture habitat is related to

  4. Prevalence of Virulence Determinants and Antimicrobial Resistance among Commensal Escherichia coli Derived from Dairy and Beef Cattle

    PubMed Central

    Bok, Ewa; Mazurek, Justyna; Stosik, Michał; Wojciech, Magdalena; Baldy-Chudzik, Katarzyna

    2015-01-01

    Cattle is a reservoir of potentially pathogenic E. coli, bacteria that can represent a significant threat to public health, hence it is crucial to monitor the prevalence of the genetic determinants of virulence and antimicrobial resistance among the E. coli population. The aim of this study was the analysis of the phylogenetic structure, distribution of virulence factors (VFs) and prevalence of antimicrobial resistance among E. coli isolated from two groups of healthy cattle: 50 cows housed in the conventional barn (147 isolates) and 42 cows living on the ecological pasture (118 isolates). The phylogenetic analysis, identification of VFs and antimicrobial resistance genes were based on either multiplex or simplex PCR. The antimicrobial susceptibilities of E. coli were examined using the broth microdilution method. Two statistical approaches were used to analyse the results obtained for two groups of cattle. The relations between the dependent (VFs profiles, antibiotics) and the independent variables were described using the two models. The mixed logit model was used to characterise the prevalence of the analysed factors in the sets of isolates. The univariate logistic regression model was used to characterise the prevalence of these factors in particular animals. Given each model, the odds ratio (OR) and the 95% confidence interval for the population were estimated. The phylogroup B1 was predominant among isolates from beef cattle, while the phylogroups A, B1 and D occurred with equal frequency among isolates from dairy cattle. The frequency of VFs-positive isolates was significantly higher among isolates from beef cattle. E. coli from dairy cattle revealed significantly higher resistance to antibiotics. Some of the tested resistance genes were present among isolates from dairy cattle. Our study showed that the habitat and diet may affect the genetic diversity of commensal E. coli in the cattle. The results suggest that the ecological pasture habitat is related to

  5. Prevalence of virulence determinants and antimicrobial resistance among commensal Escherichia coli derived from dairy and beef cattle.

    PubMed

    Bok, Ewa; Mazurek, Justyna; Stosik, Michał; Wojciech, Magdalena; Baldy-Chudzik, Katarzyna

    2015-01-19

    Cattle is a reservoir of potentially pathogenic E. coli, bacteria that can represent a significant threat to public health, hence it is crucial to monitor the prevalence of the genetic determinants of virulence and antimicrobial resistance among the E. coli population. The aim of this study was the analysis of the phylogenetic structure, distribution of virulence factors (VFs) and prevalence of antimicrobial resistance among E. coli isolated from two groups of healthy cattle: 50 cows housed in the conventional barn (147 isolates) and 42 cows living on the ecological pasture (118 isolates). The phylogenetic analysis, identification of VFs and antimicrobial resistance genes were based on either multiplex or simplex PCR. The antimicrobial susceptibilities of E. coli were examined using the broth microdilution method. Two statistical approaches were used to analyse the results obtained for two groups of cattle. The relations between the dependent (VFs profiles, antibiotics) and the independent variables were described using the two models. The mixed logit model was used to characterise the prevalence of the analysed factors in the sets of isolates. The univariate logistic regression model was used to characterise the prevalence of these factors in particular animals. Given each model, the odds ratio (OR) and the 95% confidence interval for the population were estimated. The phylogroup B1 was predominant among isolates from beef cattle, while the phylogroups A, B1 and D occurred with equal frequency among isolates from dairy cattle. The frequency of VFs-positive isolates was significantly higher among isolates from beef cattle. E. coli from dairy cattle revealed significantly higher resistance to antibiotics. Some of the tested resistance genes were present among isolates from dairy cattle. Our study showed that the habitat and diet may affect the genetic diversity of commensal E. coli in the cattle. The results suggest that the ecological pasture habitat is related to

  6. Evolution of the Antimicrobial Resistance of Staphylococcus spp. in Spain: Five Nationwide Prevalence Studies, 1986 to 2002

    PubMed Central

    Cuevas, Oscar; Cercenado, Emilia; Vindel, Ana; Guinea, Jesús; Sánchez-Conde, Matilde; Sánchez-Somolinos, Mar; Bouza, Emilio

    2004-01-01

    Data regarding the evolution of Staphylococcus resistance in a whole country have a definite influence on the design of empirical treatment regimens. Nevertheless, incidence studies over long periods of time are expensive and very difficult to carry out. In order to ascertain the present situation of the antimicrobial resistance of Staphylococcus in Spain and the change of this resistance over time, we performed five point prevalence studies (1986 to 2002) in a large group of Spanish hospitals (from 68 institutions in 1986 to 143 in 2002) collecting all Staphylococcus strains isolated on a single selected day. All microorganisms were identified in the five studies at the same laboratory, and antimicrobial susceptibility testing was performed against 17 antimicrobial agents by the agar dilution method and a microdilution method. During this period, there was an overall increase in resistance to most antimicrobials among Staphylococcus aureus/coagulase-negative staphylococci, mainly to oxacillin (1.5%/32.5% in 1986 versus 31.2%/61.3% in 2002) (P < 0.001), erythromycin (7%/41.1% in 1986 versus 31.7%/63% in 2002) (P < 0.001), gentamicin (5.2%/25.4% in 1986 versus 16.9%/27.8% in 2002) (P < 0.001; P = 0.5), and ciprofloxacin (0.6%/1.1% in 1986 versus 33.9%/44.9% in 2002) (P < 0.001). All of the isolates were uniformly susceptible to glycopeptides, linezolid, and quinupristin/dalfopristin. Resistance of S. aureus to trimethoprim/sulfamethoxazole was very low (from 0.5% to 2.1%) (P = 0.152). Periodic performance of prevalence studies is a useful, inexpensive, and easy tool to know the nationwide situation of a microorganism and its resistance to antimicrobials; it also helps us assess the emergence and spread of antimicrobial resistance. PMID:15504847

  7. Antimicrobial (Drug) Resistance

    MedlinePlus

    ... Antimicrobial (Drug) Resistance Antibiotic-Resistant Mycobacterium tuberculosis (TB) Methicillin-Resistant Staphylococcus aureus (MRSA) Vancomycin-Resistant Enterococci (VRE) Multidrug-Resistant Neisseria ...

  8. Prevalence of Salmonella serovars and antimicrobial resistance profiles in poultry of Savar area, Bangladesh.

    PubMed

    Mahmud, Md Showkat; Bari, Md Latiful; Hossain, M Anwar

    2011-10-01

    Salmonellosis is one of the major concerns in the poultry industry and some serovars of Salmonella involve in zoonosis. This study determines the seroprevalence of Salmonella in poultry and their drug-resistant patterns, variability in infectivity and mortality rate of birds, and predilection of some serovars to cause zoonoses. The average seroprevalance of Salmonella in three different age groups was found to be 37.9%. A total of 503 samples were examined over a period of 1 year from five different poultry farms of a semiurban area of Savar, Dhaka, Bangladesh. The prevalence of Salmonella was recorded to be 21.1%. Salmonella was found high in dead birds (31.2%) than live birds (18.1%). Salmonella infection was higher (23.6%) in summer than in winter (12.9%) season. Among the 106 isolates, 46 belong to serogroup B (43%) and 60 isolates to serogroup D (57%). The highest Salmonella infection was recorded as 47.9% on the 30-35-week-old birds. A total of 106 Salmonella isolates were used for antimicrobial susceptibility test against 10 common antibiotics and 17 multiple drug resistance patterns were found. Among the isolates, 69 (65%) harbored plasmids 1-4 with size variation between >1.63 and >40 kb and rest 37 (35%) isolates were plasmid free but showed resistance against 5-10 antibiotics. The results of the present investigation suggested that multiple drug resistance is common among the Salmonella isolates of poultry and some of these isolates may have zoonotic implications.

  9. Moderate Prevalence of Antimicrobial Resistance in Escherichia coli Isolates from Lettuce, Irrigation Water, and Soil

    PubMed Central

    Holvoet, Kevin; Callens, Benedicte; Dewulf, Jeroen; Uyttendaele, Mieke

    2013-01-01

    Fresh produce is known to carry nonpathogenic epiphytic microorganisms. During agricultural production and harvesting, leafy greens can become contaminated with antibiotic-resistant pathogens or commensals from animal and human sources. As lettuce does not undergo any inactivation or preservation treatment during processing, consumers may be exposed directly to all of the (resistant) bacteria present. In this study, we investigated whether lettuce or its production environment (irrigation water, soil) is able to act as a vector or reservoir of antimicrobial-resistant Escherichia coli. Over a 1-year period, eight lettuce farms were visited multiple times and 738 samples, including lettuce seedlings (leaves and soil), soil, irrigation water, and lettuce leaves were collected. From these samples, 473 isolates of Escherichia coli were obtained and tested for resistance to 14 antimicrobials. Fifty-four isolates (11.4%) were resistant to one or more antimicrobials. The highest resistance rate was observed for ampicillin (7%), followed by cephalothin, amoxicillin-clavulanic acid, tetracycline, trimethoprim, and streptomycin, with resistance rates between 4.4 and 3.6%. No resistance to amikacin, ciprofloxacin, gentamicin, or kanamycin was observed. One isolate was resistant to cefotaxime. Among the multiresistant isolates (n = 37), ampicillin and cephalothin showed the highest resistance rates, at 76 and 52%, respectively. E. coli isolates from lettuce showed higher resistance rates than E. coli isolates obtained from soil or irrigation water samples. When the presence of resistance in E. coli isolates from lettuce production sites and their resistance patterns were compared with the profiles of animal-derived E. coli strains, they were found to be the most comparable with what is found in the cattle reservoir. This may suggest that cattle are a potential reservoir of antimicrobial-resistant E. coli strains in plant primary production. PMID:23974140

  10. Streptococcus agalactiae: prevalence of antimicrobial resistance in vaginal and rectal swabs in Italian pregnant women.

    PubMed

    Matani, Chiara; Trezzi, Michele; Matteini, Alice; Catalani, Carlotta; Messeri, Daniela; Catalani, Corrado

    2016-09-01

    Intrapartum antibiotic prophylaxis (IAP) reduces both the vertical transmission of Streptococcus agalactiae or Group B Streptococcus (GBS) and the early onset of neonatal sepsis. However, existing guidelines do not recommend that antimicrobial susceptibility testing (AST) be routinely performed. Penicillin or ampicillin are indicated as first-choice antibiotics, cefazolin being an alternative in the case of history of mild allergic reactions, and vancomycin or clindamycin an alternative in the event of severe reactions. We performed a cross-sectional analysis to identify the presence of any bacterial resistance towards the antibiotics most frequently used for IAP in pregnant women with GBS positive vaginal-rectal swabs, in the Pistoia area of central Italy. Of the 255 tested samples, 65 (25.5%) were positive for GBS. Sensitivity to glycopeptides was over 90%, but lower to ampicillin and penicillin (87.10% and 87.93% respectively). Resistance towards clindamycin and erythromycin was as high as 43.75% and 32.20%. All tested GBS proved susceptible to moxifloxacin, linezolid and tigecycline. Our observed prevalence is aligned or slightly higher than data reported in other series. The less than full effectiveness and low percentages of ampicillin and penicillin sensitivity observed give cause for concern. We confirmed the increase in clindamycin and erythromycin resistance. Glycopeptides can be used as second-line antibiotics, but the complete AST of GBS should always be performed before IAP. Given that gentamicin is used synergically with penicillin when treating chorioamnionitis, it needs to be always included in the AST. This is the first study on the GBS sensitivity profile in Tuscany. Further investigation on a larger scale is required prior to implementing any changes in the current guidelines. PMID:27668902

  11. Prevalence, molecular characterization and antimicrobial resistance of Salmonella serovars isolated from northwestern Spanish broiler flocks (2011-2015).

    PubMed

    Lamas, A; Fernandez-No, I C; Miranda, J M; Vázquez, B; Cepeda, A; Franco, C M

    2016-09-01

    The present study investigated the prevalence, antimicrobial resistance to twenty antibiotics, and class 1 integron and virulence genes of Salmonella isolated from poultry houses of broilers in northwestern Spain between 2011 and 2015. Strains were classified to the serotype level using the Kauffman-White typing scheme and subtyping with enterobacterial repetitive intergenic consensus PCR. The prevalence of Salmonella spp. was 1.02%. Sixteen different serotypes were found, with S. typhimurium and S. arizonae 48:z4, z23:- being the most prevalent. A total of 59.70% of strains were resistant to at least one, and 19.70% were resistant to multiple drugs. All Salmonella spp. were susceptible to cefotaxime, ciprofloxacin, gentamicin, kanamycin, levofloxacin, neomycin, and trimethoprim. The highest level of resistance was to sulfamethoxazole (40.29%), doxycycline (17.91%), and nalidixic acid (17.91%). None of the isolates carried class 1 integron and only isolates of S. enterica subspecies enterica were positive for all virulence factors tested, whereas S. arizonae lacked genes related to replication and invasion in nonphagocytic cells. This study demonstrates that the prevalence and antimicrobial resistance of Salmonella spp. in poultry houses of broilers of northwestern Spain is low compared with those found in other studies and in other steps of the food chain.

  12. High Prevalence of Hypervirulent Klebsiella pneumoniae Infection in China: Geographic Distribution, Clinical Characteristics, and Antimicrobial Resistance.

    PubMed

    Zhang, Yawei; Zhao, Chunjiang; Wang, Qi; Wang, Xiaojuan; Chen, Hongbin; Li, Henan; Zhang, Feifei; Li, Shuguang; Wang, Ruobing; Wang, Hui

    2016-10-01

    Hypervirulent Klebsiella pneumoniae (hvKP) is traditionally defined by hypermucoviscosity, but data based on genetic background are limited. Antimicrobial-resistant hvKP has been increasingly reported but has not yet been systematically studied. K. pneumoniae isolates from bloodstream infections, hospital-acquired pneumonia, and intra-abdominal infections were collected from 10 cities in China during February to July 2013. Clinical data were collected from medical records. All K. pneumoniae isolates were investigated by antimicrobial susceptibility testing, string test, extended-spectrum β-lactamase (ESBL) gene detection, capsular serotypes, virulence gene profiles, and multilocus sequence typing. hvKP was defined by aerobactin detection. Of 230 K. pneumoniae isolates, 37.8% were hvKP. The prevalence of hvKP varied among different cities, with the highest rate in Wuhan (73.9%) and the lowest in Zhejiang (8.3%). Hypermucoviscosity and the presence of K1, K2, K20, and rmpA genes were strongly associated with hvKP (P < 0.001). A significantly higher incidence of liver abscess (P = 0.026), sepsis (P = 0.038), and invasive infections (P = 0.043) was caused by hvKP. Cancer (odds ratio [OR], 2.285) and diabetes mellitus (OR, 2.256) appeared to be independent variables associated with hvKP infections by multivariate analysis. Importantly, 12.6% of hvKP isolates produced ESBLs, and most of them carried blaCTX-M genes. Patients with neutropenia (37.5% versus 5.6%; P = 0.020), history of systemic steroid therapy (37.5% versus 5.6%; P = 0.020), and combination therapy (62.5% versus 16.7%; P = 0.009) were more likely to be infected with ESBL-producing hvKP. The prevalence of hvKP is high in China and has a varied geographic distribution. ESBL-producing hvKP is emerging, suggesting an urgent need to enhance clinical awareness, especially for immunocompromised patients receiving combination therapy. PMID:27480857

  13. Prevalence, resistance patterns, and risk factors for antimicrobial resistance in bacteria from retail chicken meat in Colombia.

    PubMed

    Donado-Godoy, Pilar; Byrne, Barbara A; León, Maribel; Castellanos, Ricardo; Vanegas, Consuelo; Coral, Adriana; Arevalo, Alejandra; Clavijo, Viviana; Vargas, Mercedes; Romero Zuñiga, Juan J; Tafur, McAllister; Pérez-Gutierrez, Enrique; Smith, Woutrina A

    2015-04-01

    As a step toward implementing the Colombian Integrated Program for Antimicrobial Resistance Surveillance (COIPARS), this study aimed to establish the baseline antimicrobial resistance patterns of Salmonella serovars, Escherichia coli, and Enterococcus spp. isolates in retail poultry meat from independent stores and from a main chain distributor center. MICs of the isolates were determined for antimicrobials used both in humans and animals, using an automated system. Salmonella serovars were isolated from 26% of the meat samples and E. coli from 83%, whereas Enterococcus faecalis and Enterococcus faecium were detected in 81 and 13% of the meat samples, respectively. A principal finding of concern in this study was that almost 98% of isolates tested were multidrug resistant. Ceftiofur, enrofloxacin, nalidixic acid, and tetracycline were the antimicrobials that showed the highest frequency of resistance among Salmonella and E. coli isolates. For enterococci, 61.5% of E. faecium isolates were found to be resistant to quinupristin-dalfopristin; this is significant because it is used to treat nosocomial infections when vancomycin resistance is present. Vancomycin resistance was detected in 4% of the E. faecalis isolates. The results of our study highlight the need for rapid implementation of an integrated program for surveillance of antimicrobial resistance by the Colombian authorities in order to monitor trends, raise awareness, and help promote practices to safeguard later generation antimicrobial agents.

  14. Prevalence and antimicrobial resistance of enterococci isolated from retail fruits, vegetables, and meats.

    PubMed

    McGowan, Lori L; Jackson, Charlene R; Barrett, John B; Hiott, Lari M; Fedorka-Cray, Paula J

    2006-12-01

    Although enterococci are considered opportunistic pathogens, they can be reservoirs of antimicrobial resistance. Antimicrobial resistance is increasingly important because of foodborne illnesses from meat and infections from produce. From 2000 through 2001, food items (vegetables, fruits, and meats) were obtained from grocery store chains in northern Georgia and cultured for the presence of enterococci; 47.7% (189 of 396) of these samples were positive for enterococci. For the fruits and vegetables, enterococci were cultured most often from tomatoes (9 of 27 samples, 33%) and radishes (10 of 11 samples, 91%), respectively. Among the meat items tested, enterococci were isolated from 95% (21 of 22) of the chicken samples, 73% (16 of 22) of the beef samples, 95% (20 of 21) of the turkey samples, and 68% (15 of 22) of the pork samples. The predominant species identified was Enterococcus faecalis (n = 80) from meat and Enterococcus casseliflavus (n = 66) from fruits and vegetables. Although high numbers of isolates were resistant to lincomycin (176 of 185 isolates, 95.1%) and bacitracin (150 of 185 isolates, 81.1%), very few isolates were resistant to salinomycin (2 isolates, 1.1%), penicillin (3 isolates, 1.6%), or nitrofurantoin (9 isolates, 4.9%). None of the isolates were resistant to linezolid or vancomycin. These data suggest that foods commonly purchased from grocery stores are a source of enterococci; however, overall resistance to antimicrobials is relatively low.

  15. Prevalence of ESBL producing Escherichia Coli and Klebsiella species with their co-resistance pattern to antimicrobials.

    PubMed

    Biswas, T; Das, M; Mondal, R; Raj, H J; Mondal, S

    2013-04-01

    Extended spectrum β-lactamase producing bacteria are potential emerging pathogens and continue to be a major challenge in clinical setup worldwide. In the present study an attempt was made to study the prevalence of extended spectrum β-lactamase producing Escherichia coli and Klebsiella species from clinical isolates in a rural tertiary care hospital in West Bengal, India with their antimicrobial susceptibility as well as co-resistance pattern to different antimicrobials. A total of 179 Escherichia coli and 62 Klebsiella isolates recovered from various clinical samples of urine, pus, aural swabs and respiratory secretions (including sputum) for a period of six months were subjected to routine antimicrobial susceptibility testing and also tested for extended spectrum β-lactamase production as per NCCLS recommendations. Extended spectrum β-lactamase was detected in 32.40% of Escherichia coli and 40.32% of Klebsiella species isolates. Urine, pus and respiratory samples were common source of extended spectrum β-lactamase producers and resistance rate of these organisms to third generation cephalosporins were more than 30 to 40%. Co-resistance pattern of these extended spectrum β-lactamase producers to other commonly used antimicrobials were also statistically significant (p≤0.05). From the study it is concluded that indiscriminate use of third generation cephalosporins may be responsible for the selection of extended spectrum β-lactamase producing multidrug resistant strains in hospital setup and amikacin is a reliable drug against them.

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

    PubMed

    Ram, Siya; Vajpayee, Poornima; Shanker, Rishi

    2007-11-01

    The consumption of polluted surface water for domestic and recreational purposes by large populations in developing nations is a major cause of diarrheal disease related mortality. The river Ganga and its tributaries meet 40% of the water requirement for drinking and irrigation in India. In this study, Escherichia coli isolates (n=75) of the river Ganga water were investigated for resistance to antimicrobial agents (n=15) and virulence genes specific to shiga toxin (STEC) and enterotoxin producing E. coli (ETEC). E. coli isolates from the river Ganga water exhibit resistance to multiple antimicrobial agents. The distribution of antimicrobial agent resistance in E. colivaries significantly (chi2: 81.28 at df = 24, p < 0.001) between the sites. Both stx1 and stx2 genes were present in 82.3% of STEC (n=17) while remaining isolates possess either stxl (11.8%) or stx2 (5.9%). The presence of eaeA, hlyA, and chuA genes was observed in 70.6, 88.2, and 58.8% of STEC, respectively. Both LT1 and ST1 genes were positive in 66.7% of ETEC (n=15) while 33.3% of isolates harbor only LT1 gene. The prevalence of multi-antimicrobial-agent resistant E. coli in the river Ganga water poses increased risk of infections in the human population.

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

    PubMed

    Ram, Siya; Vajpayee, Poornima; Shanker, Rishi

    2007-11-01

    The consumption of polluted surface water for domestic and recreational purposes by large populations in developing nations is a major cause of diarrheal disease related mortality. The river Ganga and its tributaries meet 40% of the water requirement for drinking and irrigation in India. In this study, Escherichia coli isolates (n=75) of the river Ganga water were investigated for resistance to antimicrobial agents (n=15) and virulence genes specific to shiga toxin (STEC) and enterotoxin producing E. coli (ETEC). E. coli isolates from the river Ganga water exhibit resistance to multiple antimicrobial agents. The distribution of antimicrobial agent resistance in E. colivaries significantly (chi2: 81.28 at df = 24, p < 0.001) between the sites. Both stx1 and stx2 genes were present in 82.3% of STEC (n=17) while remaining isolates possess either stxl (11.8%) or stx2 (5.9%). The presence of eaeA, hlyA, and chuA genes was observed in 70.6, 88.2, and 58.8% of STEC, respectively. Both LT1 and ST1 genes were positive in 66.7% of ETEC (n=15) while 33.3% of isolates harbor only LT1 gene. The prevalence of multi-antimicrobial-agent resistant E. coli in the river Ganga water poses increased risk of infections in the human population. PMID:18044515

  18. Prevalence and Antimicrobial Resistance of Salmonella and Escherichia coli from Australian Cattle Populations at Slaughter.

    PubMed

    Barlow, Robert S; McMillan, Kate E; Duffy, Lesley L; Fegan, Narelle; Jordan, David; Mellor, Glen E

    2015-05-01

    Antimicrobial agents are used in cattle production systems for the prevention and control of bacteria associated with diseases. Australia is the world's third largest exporter of beef; however, this country does not have an ongoing surveillance system for antimicrobial resistance (AMR) in cattle or in foods derived from these animals. In this study, 910 beef cattle, 290 dairy cattle, and 300 veal calf fecal samples collected at slaughter were examined for the presence of Escherichia coli and Salmonella, and the phenotypic AMR of 800 E. coli and 217 Salmonella isolates was determined. E. coli was readily isolated from all types of samples (92.3% of total samples), whereas Salmonella was recovered from only 14.4% of samples and was more likely to be isolated from dairy cattle samples than from beef cattle or veal calf samples. The results of AMR testing corroborate previous Australian animal and retail food surveys, which have indicated a low level of AMR. Multidrug resistance in Salmonella isolates from beef cattle was detected infrequently; however, the resistance was to antimicrobials of low importance in human medicine. Although some differences in AMR between isolates from the different types of animals were observed, there is minimal evidence that specific production practices are responsible for disproportionate contributions to AMR development. In general, resistance to antimicrobials of critical and high importance in human medicine was low regardless of the isolate source. The low level of AMR in bacteria from Australian cattle is likely a result of strict regulation of antimicrobials in food animals in Australia and animal management systems that do not favor bacterial disease. PMID:25951384

  19. Prevalence and Antimicrobial Resistance of Salmonella and Escherichia coli from Australian Cattle Populations at Slaughter.

    PubMed

    Barlow, Robert S; McMillan, Kate E; Duffy, Lesley L; Fegan, Narelle; Jordan, David; Mellor, Glen E

    2015-05-01

    Antimicrobial agents are used in cattle production systems for the prevention and control of bacteria associated with diseases. Australia is the world's third largest exporter of beef; however, this country does not have an ongoing surveillance system for antimicrobial resistance (AMR) in cattle or in foods derived from these animals. In this study, 910 beef cattle, 290 dairy cattle, and 300 veal calf fecal samples collected at slaughter were examined for the presence of Escherichia coli and Salmonella, and the phenotypic AMR of 800 E. coli and 217 Salmonella isolates was determined. E. coli was readily isolated from all types of samples (92.3% of total samples), whereas Salmonella was recovered from only 14.4% of samples and was more likely to be isolated from dairy cattle samples than from beef cattle or veal calf samples. The results of AMR testing corroborate previous Australian animal and retail food surveys, which have indicated a low level of AMR. Multidrug resistance in Salmonella isolates from beef cattle was detected infrequently; however, the resistance was to antimicrobials of low importance in human medicine. Although some differences in AMR between isolates from the different types of animals were observed, there is minimal evidence that specific production practices are responsible for disproportionate contributions to AMR development. In general, resistance to antimicrobials of critical and high importance in human medicine was low regardless of the isolate source. The low level of AMR in bacteria from Australian cattle is likely a result of strict regulation of antimicrobials in food animals in Australia and animal management systems that do not favor bacterial disease.

  20. Prevalence and antimicrobial resistance profile of Staphylococcus species in chicken and beef raw meat in Egypt.

    PubMed

    Osman, Kamelia M; Amer, Aziza M; Badr, Jihan M; Saad, Aalaa S A

    2015-05-01

    Coagulase-positive (CPS) and coagulase-negative (CNS) staphylococci cause staphylococcal food poisoning. Recently, CPS and CNS have received increasing attention due to their potential role in the dissemination of antibiotic resistance markers. The present study aimed to evaluate CPS and CNS species distribution and their antibiotic resistance profile isolated from chicken and beef meat. Fifty fresh, uncooked chicken parts and 50 beef meat cuts (local n=27; imported n=23) were used. One hundred staphylococcal isolates belonging to 11 species were isolated and identified from chicken (n=50) and beef (n=50) raw meat samples. Staphylococcus hyicus (26/100), lugdunensis (18/100), aureus (15/100) and epidermidis (14/100) were dominant. S. aureus was 100% resistant to penicillin and sulfamethoxazole/trimethoprim. Vancomycin-resistant S. aureus showed intermediate resistance (51%), which might indicate the dissemination of vancomycin resistance in the community and imply food safety hazards. The percentage of resistance to β-lactams was variable, with the highest resistance being to penicillin (94%) and lowest to ampicillin-sulbactam (22%). Antimicrobial resistance was mainly against penicillin (94%), clindamycin (90%) and sulfamethoxazole/trimethoprim (82%). The results indicate that chicken and beef raw meat are an important source of antibiotic-resistant CPS and CNS.

  1. Prevalence and antimicrobial resistance profile of Staphylococcus species in chicken and beef raw meat in Egypt.

    PubMed

    Osman, Kamelia M; Amer, Aziza M; Badr, Jihan M; Saad, Aalaa S A

    2015-05-01

    Coagulase-positive (CPS) and coagulase-negative (CNS) staphylococci cause staphylococcal food poisoning. Recently, CPS and CNS have received increasing attention due to their potential role in the dissemination of antibiotic resistance markers. The present study aimed to evaluate CPS and CNS species distribution and their antibiotic resistance profile isolated from chicken and beef meat. Fifty fresh, uncooked chicken parts and 50 beef meat cuts (local n=27; imported n=23) were used. One hundred staphylococcal isolates belonging to 11 species were isolated and identified from chicken (n=50) and beef (n=50) raw meat samples. Staphylococcus hyicus (26/100), lugdunensis (18/100), aureus (15/100) and epidermidis (14/100) were dominant. S. aureus was 100% resistant to penicillin and sulfamethoxazole/trimethoprim. Vancomycin-resistant S. aureus showed intermediate resistance (51%), which might indicate the dissemination of vancomycin resistance in the community and imply food safety hazards. The percentage of resistance to β-lactams was variable, with the highest resistance being to penicillin (94%) and lowest to ampicillin-sulbactam (22%). Antimicrobial resistance was mainly against penicillin (94%), clindamycin (90%) and sulfamethoxazole/trimethoprim (82%). The results indicate that chicken and beef raw meat are an important source of antibiotic-resistant CPS and CNS. PMID:25789407

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

    PubMed Central

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

    2016-01-01

    Background: 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. Methods: 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. Results: 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. Conclusions: 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. PMID:27124686

  3. A five-year study on prevalence and antimicrobial resistance of Campylobacter from poultry carcasses in Poland.

    PubMed

    Wieczorek, Kinga; Osek, Jacek

    2015-08-01

    During 2009-2013 a total of 2114 swab samples collected from broiler carcasses in all 16 voivodeships (administrative districts) of Poland were examined for the presence of Campylobacter jejuni and Campylobacter coli. The antimicrobial resistance of the isolates to ciprofloxacin, tetracycline and erythromycin using the MIC method was also tested. It was found that 1151 (54.4%) carcasses were contaminated with Campylobacter, with 50% of C. jejuni and C. coli species isolated from positive samples. The temporal trend in the prevalence of Campylobacter-positive samples demonstrated that the highest percentage of carcasses was contaminated during the first year of the survey (70.5%) whereas in the last year (2013) only 36.3% of broilers contained these bacteria. Antimicrobial resistance analysis showed that overall 939 (81.6%) of isolates were resistant to ciprofloxacin, 646 (56.1%) to tetracycline but only 28 (2.4%) to erythromycin. Significant differences in resistance profiles between C. jejuni and C. coli were observed with greater resistance level observed in the latter species. Furthermore, a significant increase in the percentage of C. jejuni resistant to ciprofloxacin (from 59.6% in 2009 to 85.9% in 2014) and to tetracycline (from 23.2% to 70.4%, respectively) was identified. Only 20 (1.7%) Campylobacter isolates displayed a multiresistance pattern.

  4. Prevalence of antimicrobial resistance in faecal enterococci from vet-visiting pets and assessment of risk factors.

    PubMed

    Leite-Martins, L; Mahú, M I; Costa, A L; Bessa, L J; Vaz-Pires, P; Loureiro, L; Niza-Ribeiro, J; de Matos, A J F; Martins da Costa, P

    2015-06-27

    The objective of this study was to determine the prevalence of antimicrobial resistance (AMR) exhibited by enterococci isolated from faeces of pets and its underlying risk factors. From September 2009 to May 2012, rectal swabs were collected from 74 dogs and 17 cats, selected from the population of animals visiting the Veterinary Hospital of University of Porto, UPVet, through a systematic random procedure. Animal owners answered a questionnaire about the risk factors that could influence the presence of AMR in faecal enterococci. Enterococci isolation, identification and antimicrobial (AM) susceptibility testing were performed. Data analyses of multilevel, univariable and multivariable generalised linear mixed models were conducted. From all enterococci isolated (n=315), 61 per cent were considered multidrug-resistant, whereas only 9.2 per cent were susceptible to all AMs tested. Highest resistance was found to tetracycline (67.0 per cent), rifampicin (60.3 per cent), azithromycin (58.4 per cent), quinupristin/dalfopristin (54.0 per cent) and erythromycin (53.0 per cent). Previous fluoroquinolone treatments and coprophagic habits were the features more consistently associated with the presence of AMR for three (chloramphenicol, ciprofloxacin and azithromycin) and seven (tetracycline, rifampicin, gentamicin, chloramphenicol, ciprofloxacin, erythromycin and azithromycin), respectively, out of nine AMs assessed. Evaluating risk factors that determine the presence of drug-resistant bacteria in pets, a possible source of resistance determinants to human beings, is crucial for the selection of appropriate treatment guidelines by veterinary practitioners.

  5. Antimicrobial Resistance

    MedlinePlus

    ... and health professionals can play their part; rewarding innovation and development of new treatment options and other ... and industry can help tackle resistance by: fostering innovation and research and development of new vaccines, diagnostics, ...

  6. Prevalence, Molecular Characterization, and Antimicrobial Susceptibility of Methicillin-Resistant Staphylococcus aureus Isolated from Milk and Dairy Products.

    PubMed

    Al-Ashmawy, Maha Abdou; Sallam, Khalid Ibrahim; Abd-Elghany, Samir Mohammed; Elhadidy, Mohamed; Tamura, Tomohiro

    2016-03-01

    The present work was undertaken to study the prevalence, molecular characterization, virulence factors, and antimicrobial susceptibility of methicillin-resistant Staphylococcus aureus (MRSA) in raw milk and dairy products in Mansoura City, Egypt. MRSA was detected in 53% (106/200) among all milk and dairy products with prevalence rates of 75%, 65%, 40%, 50%, and 35% in raw milk, Damietta cheese, Kareish cheese, ice cream, and yogurt samples, respectively. The mean S. aureus counts were 3.49, 3.71, 2.93, 3.40, and 3.23 log10 colony-forming units (CFU)/g among tested raw milk, Damietta cheese, Kareish cheese, ice cream and yogurt, respectively, with an overall count of 3.41 log10 CFU/g. Interestingly, all recovered S. aureus isolates were genetically verified as MRSA strains by molecular detection of the mecA gene. Furthermore, genes encoding α-hemolysin (hla) and staphylococcal enterotoxins (sea, seb, sec) were detected in all isolates. The antimicrobial susceptibility pattern of recovered MRSA isolates against 13 tested antimicrobials revealed that the least effective drugs were penicillin G, cloxacillin, tetracycline, and amoxicillin with bacterial resistance percentages of 87.9%, 75.9%, 65.2%, and 55.6%, respectively. These findings suggested that milk and dairy products represent a potential infection risk threat of multidrug-resistant and toxigenic S. aureus in Egypt due to neglected hygienic practices during production, retail, or storage stages. These findings highlighted the crucial importance of applying more restrictive hygienic measures in dairy production in Egypt for food safety.

  7. Prevalence of Salmonella isolates and antimicrobial resistance patterns in chicken meat throughout Japan.

    PubMed

    Iwabuchi, Eriko; Yamamoto, Shiori; Endo, Yasuhisa; Ochiai, Tameichi; Hirai, Katsuya

    2011-02-01

    We investigated the prevalence of Salmonella in chicken meat from northern, central, and southern Japan. Between 2006 and 2008, 821 samples from these three regions were collected and examined. Salmonella isolates were detected in 164 (20.0%) of these samples, with 15 (10.0%) of 150, 113 (27.5%) of 411, and 36 (13.8%) of 260 recovered from the northern, central, and southern regions, respectively. We recovered 452 Salmonella isolates. From the isolates, 27 serovars were identified; the predominant serovars isolated were Salmonella Infantis (n=81), Salmonella Kalamu (n=56), and Salmonella Schwarzengrund (n=43). Of the 452 isolates, 443 (98.0%) were resistant to one or more antibiotics, and 221 (48.9%) showed multiple-antibiotic resistance, thereby implying that multiple-antibiotic resistant Salmonella organisms are widespread in chicken meat in Japan. Resistance to oxytetracycline was most common (72.6%), followed by dihydrostreptomycin (69.2%) and bicozamycin (49.1%). This study, the first to report Salmonella prevalence in chicken meat throughout Japan, could provide valuable data for monitoring and controlling Salmonella infection in the future.

  8. Antimicrobial resistance in Canada

    PubMed Central

    Conly, John

    2002-01-01

    Antibiotic resistance has increased rapidly during the last decade, creating a serious threat to the treatment of infectious diseases. Canada is no exception to this worldwide phenomenon. Data from the Canadian Nosocomial Infection Surveillance Program have revealed that the incidence of methicillin-resistant Staphylococcus aureus, as a proportion of S. aureus isolates, increased from 1% in 1995 to 8% by the end of 2000, and vancomycin-resistant enterococcus has been documented in all 10 provinces since the first reported outbreak in 1995. The prevalence of nonsusceptible Streptococcus pneumoniae in Canada in 2000 was found to be 12%. Human antimicrobial prescriptions, adjusted for differences in the population, declined 11% based on the total number of prescriptions dispensed between 1995 and 2000. There was also a 21% decrease in β-lactam prescriptions during this same period. These data suggest that systematic efforts to reduce unnecessary prescribing of antimicrobials to outpatients in Canada, beginning after a national consensus conference in 1997, may be having an impact. There is, however, still a need for continued concerted efforts on a national, provincial and regional level to quell the rising tide of antibiotic resistance. PMID:12406948

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

    PubMed

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

    2015-11-01

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

  10. The prevalence, antimicrobial resistance and PFGE profiles of Laribacter hongkongensis in retail freshwater fish and edible frogs of southern China.

    PubMed

    Feng, Jia-li; Hu, Jing; Lin, Jin-yan; Liu, Shan; Chowdhury, Nityananda; Zhang, Ou; Li, Jian-dong; Shi, Lei; Yamasaki, Shinji; Chen, Qing

    2012-10-01

    Laribacter hongkongensis is a novel emerging pathogen associated with human gastroenteritis. We aimed to investigate the prevalence, antimicrobial resistance and genotypic relationship of 199 L. hongkongensis isolates from 690 intestinal samples of fish and frogs. These samples were collected from retail markets in the city of Guangzhou in southern China from October 2008 to September 2009. L. hongkongensis was detected in from 80 (16.3%) out of 490 freshwater fish, and this number included 76 (32.3%) out of 235 grass carp and 4 (14.8%) out of 27 bighead carp. A higher isolation rate of 59.5% (119 out of 200) was observed in edible frogs. The isolation rate was highest in the spring in comparison with other seasons. Notably, 63.8% of the isolates were resistant to at least one class of antimicrobial agents. Analysis by pulsed-field gel electrophoresis (PFGE) revealed that the isolates could be grouped into three clusters. Isolates from fish intestines were grouped into two clusters: cluster I and II. Isolates of frog-origin and several fish-origin isolates were grouped into cluster III. Two patient-derived strains could be classed into cluster III. Extensive genetic heterogeneity among the isolates was observed. The results indicate that L. hongkongensis isolates exhibits host tropism, extensive resistance to widely used antimicrobials and diverse biological evolution in an aquatic environment. The frog is more likely than the freshwater fish to be the potential source for human infection with L. hongkongensis. PMID:22850382

  11. Rising Prevalence of Antimicrobial Resistance in Urinary Tract Infections During Pregnancy: Necessity for Exploring Newer Treatment Options

    PubMed Central

    Rizvi, Meher; Khan, Fatima; Shukla, Indu; Malik, Abida; Shaheen

    2011-01-01

    Background: Urinary tract infections (UTI) are one of the most common medical complications of pregnancy. The emergence of drug resistance and particularly the Extended-spectrum beta-lactamase production by Escherichia coli and methicillin resistance in Staphylococci, limits the choice of antimicrobials. Materials and Methods: Patients in different stages of pregnancy with or without symptoms of urinary tract infection attending the antenatal clinic of obstetrics and gynaecology were screened for significant bacteriuria, by standard loop method on 5% sheep blood agar and teepol lactose agar. Isolates were identified by using standard biochemical tests and antimicrobial susceptibility testing was done using Kirby Bauer disc diffusion method. Results: A total of 4290 (51.2%) urine samples from pregnant females showed growth on culture. Prevalence of asymptomatic bacteriuria 3210 (74.8%) was higher than symptomatic UTI 1080 (25.2%). Escherichia coli was the most common pathogen accounting for 1800 (41.9%) of the urinary isolates. Among the gram-positive cocci, coagulase negative species of Staphylococci 270 (6.4%) were the most common pathogen. Significantly high resistance was shown by the gram negative bacilli as well as gram positive cocci to the β-lactam group of antimicrobials, flouroquinolones and aminoglycosides. Most alarming was the presence of ESBL in 846 (47%) isolates of Escherichia coli and 344 (36.9%) isolates of Klebsiella pneumoniae, along with the presence of methicillin resistance in 41% of Staphylococcus species and high-level aminoglycoside resistance in 45(30%) isolates of Enterococcus species. Glycopeptides and carbepenems were the only group of drugs to which all the strains of gram positive cocci and gram negative bacilli were uniformly sensitive, respectively. Conclusions: Regular screening should be done for the presence of symptomatic or asymptomatic bacteriuria in pregnancy and specific guidelines should be issued for testing antimicrobial

  12. High prevalence of Escherichia coli sequence type 131 among antimicrobial-resistant E. coli isolates from geriatric patients.

    PubMed

    Ho, Pak-Leung; Chu, Yuki Pui-Shan; Lo, Wai-U; Chow, Kin-Hung; Law, Pierra Y; Tse, Cindy Wing-Sze; Ng, Tak-Keung; Cheng, Vincent Chi-Chung; Que, Tak-Lun

    2015-03-01

    Previous work on the subclones within Escherichia coli ST131 predominantly involved isolates from Western countries. This study assessed the prevalence and antimicrobial resistance attributed to this clonal group. A total of 340 consecutive, non-duplicated urinary E. coli isolates originating from four clinical laboratories in Hong Kong in 2013 were tested. ST131 prevalence among the total isolates was 18.5 % (63/340) and was higher among inpatient isolates (23.0 %) than outpatient isolates (11.8 %, P<0.001), and higher among isolates from patients aged ≥65 years than from patients aged 18-50 years and 51-64 years (25.4 vs 3.4 and 4.0 %, respectively, P<0.001). Of the 63 ST131 isolates, 43 (68.3 %) isolates belonged to the H30 subclone, whereas the remaining isolates belonged to H41 (n = 17), H54 (n = 2) and H22 (n = 1). All H30 isolates were ciprofloxacin-resistant, of which 18.6 % (8/43) belonged to the H30-Rx subclone. Twenty-six (41.3 %) ST131 isolates were ESBL-producers, of which 19 had blaCTX-M-14 (12 non-H30-Rx, two H30-Rx and five H41), six had blaCTX-M-15 (five non-H30-Rx and one H30-Rx) and one was blaCTX-M-negative (H30). In conclusion, ST131 accounts for a large share of the antimicrobial-resistant E. coli isolates from geriatric patients. Unlike previous reports, ESBL-producing ST131 strains mainly belonged to non-H30-Rx rather than the H30-Rx subclone, with blaCTX-M-14 as the dominant enzyme type.

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

    PubMed Central

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

    2015-01-01

    Objectives To describe the prevalence of antimicrobial resistance among commensal Escherichia coli isolates on household and small-scale chicken farms, common in southern Vietnam, and to investigate the association of antimicrobial resistance with farming practices and antimicrobial usage. Methods We collected data on farming and antimicrobial usage from 208 chicken farms. E. coli was isolated from boot swab samples using MacConkey agar (MA) and MA with ceftazidime, nalidixic acid or gentamicin. Isolates were tested for their susceptibility to 11 antimicrobials and for ESBL production. Risk factor analyses were carried out, using logistic regression, at both the bacterial population and farm levels. Results E. coli resistant to gentamicin, ciprofloxacin and third-generation cephalosporins was detected on 201 (96.6%), 191 (91.8%) and 77 (37.0%) of the farms, respectively. Of the 895 E. coli isolates, resistance to gentamicin, ciprofloxacin and third-generation cephalosporins was detected in 178 (19.9%), 291 (32.5%) and 29 (3.2%) of the isolates, respectively. Ciprofloxacin resistance was significantly associated with quinolone usage (OR = 2.26) and tetracycline usage (OR = 1.70). ESBL-producing E. coli were associated with farms containing fish ponds (OR = 4.82). Conclusions Household and small farms showed frequent antimicrobial usage associated with a high prevalence of resistance to the most commonly used antimicrobials. Given the weak biocontainment, the high prevalence of resistant E. coli could represent a risk to the environment and to humans. PMID:25755000

  14. Prevalence, characterization, and antimicrobial resistance of Aeromonas strains from various retail food products in Mumbai, India.

    PubMed

    Nagar, Vandan; Shashidhar, Ravindranath; Bandekar, Jayant R

    2011-09-01

    A total of 154 food samples (chicken, fish, and ready-to-eat sprouts) from various retail outlets in Mumbai, India, were analyzed for the presence of Aeromonas spp. over a period of 2 y (January 2006 to March 2008). Twenty-two Aeromonas isolates belonging to 7 different species were isolated from 18 (11.7%) food samples. The highest percentages of isolation were from chicken (28.6%) followed by fish (20%) and sprout (2.5%) samples. Aeromonas caviae, A. veronii bv. sobria, and A. salmonicida were the most frequently isolated species from sprouts, chicken, and fish samples, respectively. The genes encoding for putative virulence factors, cytotoxic enterotoxin (act), hemolysin (hly), aerolysin (aer), elastase (ahyB), and lipase (lip) were detected using polymerase chain reaction method in 59.1%, 40.9%, 22.7%, 54.5%, and 31.8% of the strains, respectively. The isolated Aeromonas strains were found to be positive for virulence factors, that is, amylase, DNase, gelatinase, protease, and lipase production. More than 60% isolates were also positive for β-hemolytic activity. All these food isolates were found to be resistant to ampicillin and bacitracin, and sensitive to gentamicin, 3rd-generation cephalosporins (ceftazidime, cephotaxime, ceftriaxone), and chloramphenicol. Seventeen (77.2%) isolates harbored single and/or multiple plasmids (approximately 5 to >16 kb). The XbaI digestion patterns of chromosomal DNA of these isolates, using pulsed field gel electrophoresis, showed high genetic diversity among these isolates. Our results demonstrate the presence of various Aeromonas spp. with virulence potential and antimicrobial resistance in different food products marketed in Mumbai, India. The potential health risks posed by consumption of these raw or undercooked food products should not be underestimated.

  15. Impact of wastewater from different sources on the prevalence of antimicrobial-resistant Escherichia coli in sewage treatment plants in South India.

    PubMed

    Akiba, Masato; Senba, Hironobu; Otagiri, Haruna; Prabhasankar, Valipparambil P; Taniyasu, Sachi; Yamashita, Nobuyoshi; Lee, Ken-ichi; Yamamoto, Takehisa; Tsutsui, Toshiyuki; Ian Joshua, Derrick; Balakrishna, Keshava; Bairy, Indira; Iwata, Taketoshi; Kusumoto, Masahiro; Kannan, Kurunthachalam; Guruge, Keerthi S

    2015-05-01

    The sewage treatment plant (STP) is one of the most important interfaces between the human population and the aquatic environment, leading to contamination of the latter by antimicrobial-resistant bacteria. To identify factors affecting the prevalence of antimicrobial-resistant bacteria, water samples were collected from three different STPs in South India. STP1 exclusively treats sewage generated by a domestic population. STP2 predominantly treats sewage generated by a domestic population with a mix of hospital effluent. STP3 treats effluents generated exclusively by a hospital. The water samples were collected between three intermediate treatment steps including equalization, aeration, and clarification, in addition to the outlet to assess the removal rates of bacteria as the effluent passed through the treatment plant. The samples were collected in three different seasons to study the effect of seasonal variation. Escherichia coli isolated from the water samples were tested for susceptibility to 12 antimicrobials. The results of logistic regression analysis suggest that the hospital wastewater inflow significantly increased the prevalence of antimicrobial-resistant E. coli, whereas the treatment processes and sampling seasons did not affect the prevalence of these isolates. A bias in the genotype distribution of E. coli was observed among the isolates obtained from STP3. In conclusion, hospital wastewaters should be carefully treated to prevent the contamination of Indian environment with antimicrobial-resistant bacteria.

  16. Prevalence, risk factors, and antimicrobial resistance profiles of Salmonella from commercial broiler farms in two important poultry-producing regions of Colombia.

    PubMed

    Donado-Godoy, P; Gardner, I; Byrne, B A; Leon, M; Perez-Gutierrez, E; Ovalle, M V; Tafur, M A; Miller, W

    2012-05-01

    Salmonella is one of the most common foodborne pathogens associated with diarrheal disease in humans. Food animals, especially poultry, are important direct and indirect sources of human salmonellosis, and antimicrobial resistance is an emerging problem of public health concern. The use of antimicrobials benefits producers but contributes to the emergence of antimicrobial resistant bacteria. As a step toward implementing the Colombian Integrated Program for Antimicrobial Resistance Surveillance, this study was conducted to establish the prevalence, distribution of serovars, antimicrobial resistance profiles, and risk factors for Salmonella on poultry farms in the two largest states of poultry production in Colombia. Salmonella was isolated from 41% of farms and 65% of the 315 chicken houses sampled. Salmonella Paratyphi B variant Java was the most prevalent serovar (76%), followed by Salmonella Heidelberg (23%). All Salmonella isolates were resistant to 2 to 15 of the antimicrobial drugs tested in this study. For Salmonella Paratyphi B variant Java, 34 drug resistance patterns were present. The predominant resistance pattern was ciprofloxacin, nitrofurantoin, tetracycline, trimethoprim-sulfamethoxazole, ceftiofur, streptomycin, enrofloxacin, and nalidixic acid; this pattern was detected in 15% of isolates. The resistance pattern of tetracycline, ceftiofur, and nalidixic acid was found in over 40% of the isolates of Salmonella Heidelberg. Of the biosecurity practices considered, two factors were significantly associated with reduction in Salmonella: cleaning of fixed equipment and composting of dead birds on the farm. Findings from the present study provide scientific evidence to inform implementation of official policies that support new biosecurity legislation in an effort to decrease the prevalence of Salmonella on Colombian poultry farms.

  17. Comparative Prevalence of Antimicrobial Resistance in Community-Acquired Urinary Tract Infection Cases from Representative States of Northern and Southern India

    PubMed Central

    Gupta, Shivani; Padmavathi, DV

    2014-01-01

    Context: Urinary tract infections (UTIs) are amongst the most common infections described in outpatient settings. Increased antimicrobial resistance (AMR) of urinary tract pathogens is a matter of global public health concern. Treatment of UTI depends on both prevalence and antimicrobial resistance (AMR) of causative bacteria at any specific geographical location. Aim: This study was undertaken to compare the prevalence of uropathogens and their AMR profile in two different geographical parts of India. Materials and Methods: Clean-catch mid-stream urine samples were collected from adult patients, bacterial flora isolated from human urine was evaluated for antimicrobial susceptibility profile using Kirby Bauer’s disc diffusion method among patients from Hyderabad (Southern India), Rajasthan and Punjab (Northern India). The data were analysed using Chi-square (χ2) test, confidence interval (CI), odds ratio (OR) analysis and p-value using SPSS 16 software. Results: Escherichia coli (55.1%) were the most prevalent isolates followed by Enterococcus faecalis (15.8%). Amikacin was the most active antimicrobial agents which showed low resistance rate of 14%. The present study revealed the geographical difference in prevalence of uropathogens with Klebsiella pneumoniae being the second most common uropathogen followed by E. faecalis in the states from northern India while no K. pneumoniae was seen in samples from southern India but E. faecalis was the second most prevalent organism. Conclusion: Therefore, development of regional surveillance programs is highly recommended for implementation of national CA-UTI guidelines in Indian settings. PMID:25386432

  18. Shigella in Brazilian children with acute diarrhoea: prevalence, antimicrobial resistance and virulence genes

    PubMed Central

    Sousa, Mireille Ângela Bernardes; Mendes, Edilberto Nogueira; Collares, Guilherme Birchal; Péret-Filho, Luciano Amedée; Penna, Francisco José; Magalhães, Paula Prazeres

    2013-01-01

    Diarrhoeal disease is still considered a major cause of morbidity and mortality among children. Among diarrhoeagenic agents, Shigella should be highlighted due to its prevalence and the severity of the associated disease. Here, we assessed Shigella prevalence, drug susceptibility and virulence factors. Faeces from 157 children with diarrhoea who sought treatment at the Children's Hospital João Paulo II, a reference children´s hospital in Belo Horizonte, state of Minas Gerais, Brazil, were cultured and drug susceptibility of the Shigella isolates was determined by the disk diffusion technique. Shigella virulence markers were identified by polymerase chain reaction. The bacterium was recovered from 10.8% of the children (88.2% Shigella sonnei). The ipaH, iuc, sen and ial genes were detected in strains isolated from all shigellosis patients; set1A was only detected in Shigella flexneri. Additionally, patients were infected by Shigella strains of different ial, sat, sen and set1A genotypes. Compared to previous studies, we observed a marked shift in the distribution of species from S. flexneri to S. sonnei and high rates of trimethoprim/sulfamethoxazole resistance. PMID:23440111

  19. Antimicrobial resistance in livestock.

    PubMed

    Catry, B; Laevens, H; Devriese, L A; Opsomer, G; De Kruif, A

    2003-04-01

    Antimicrobial resistance may become a major problem in veterinary medicine as a consequence of the intensive use and misuse of antimicrobial drugs. Related problems are now arising in human medicine, such as the appearance of multi-resistant food-borne pathogens. Product characteristics, dose, treatment interval and duration of treatment influence the selection pressure for antimicrobial drug resistance. There are theoretical, experimental and clinical indications that the emergence of de novo resistance in a pathogenic population can be prevented by minimizing the time that suboptimal drug levels are present in the infected tissue compartment. Until recently, attention has been focused on target pathogens. However, it should be kept in mind that when antimicrobial drugs are used in an individual, resistance selection mainly affects the normal body flora. In the long term, this is at least equally important as resistance selection in the target pathogens, as the horizontal transfer of resistance genes converts almost all pathogenic bacteria into potential recipients for antimicrobial resistance. Other factors contributing to the epidemiology of antimicrobial resistance are the localization and size of the microbial population, and the age, immunity and contact intensity of the host. In livestock, dynamic herd-related resistance patterns have been observed in different animal species.

  20. Short communication: Prevalence, antimicrobial resistance, and resistant traits of coagulase-negative staphylococci isolated from cheese samples in Turkey.

    PubMed

    Kürekci, Cemil

    2016-04-01

    A total of 17 coagulase-negative staphylococci (CNS) isolates obtained from 72 cheese samples were included in this study. Coagulase-negative staphylococci isolates obtained in this study comprised 6 (35.3%) Staphylococcus saprophyticus, 3 (17.6%) Staphylococcus epidermidis, 2 (11.8%) Staphylococcus hominis, 2 (11.8%) Staphylococcus haemolyticus, 1 (5.9%) Staphylococcus xylosus, 1 (5.9%) Staphylococcus vitulinus, 1 (5.9%) Staphylococcus lentus, and 1 (5.9%) Staphylococcus warneri. The disc diffusion assay revealed that the highest occurrence of resistance was found for penicillin (76.5%), erythromycin (35.3%), tetracycline (29.4%), and trimethoprim-sulfamethoxazole (17.6%) among CNS isolates. However, all CNS isolates were found to be susceptible to vancomycin, streptomycin, linezolid, and gentamycin. Of the isolates, 64.7% carried at least one of the following antimicrobial resistance genes: mecA, tet(M), erm(B), blaZ, ant(4')-la, aph(3')-IIIa, and lnu(A). The results suggest that improved hygienic conditions, such as safer handling of raw milk, proper cleaning, and sanitation during the manufacturing in the dairies, are urgently needed in Turkey. PMID:26874419

  1. Prevalence, virulence, and antimicrobial resistance of Campylobacter jejuni and Campylobacter coli in white stork Ciconia ciconia in Poland.

    PubMed

    Szczepańska, Bernadeta; Kamiński, Piotr; Andrzejewska, Małgorzata; Śpica, Dorota; Kartanas, Edmund; Ulrich, Werner; Jerzak, Leszek; Kasprzak, Mariusz; Bocheński, Marcin; Klawe, Jacek J

    2015-01-01

    The aim of this study was to investigate the role of white stork Ciconia ciconia as a potential reservoir of Campylobacter spp. Antimicrobial resistance and the presence of putative virulence genes of the isolates were also examined. A total of 398 white stork chicks sampled in Western Poland in habitats with high density of breeding were examined. Rectal swabs were collected during breeding season 2009-2012 from storks developing in a relatively pure environment (Odra meadows), in polluted areas (a copper mining-smelting complex), and in suburbs. Of the anal swabs collected, 7.6% were positive for Campylobacter among chicks (5.3% samples positive for C. jejuni and 2.3% samples positive for C. coli). Samples from polluted areas had the highest prevalence of Campylobacter (12.2%). The prevalence of resistance among C. jejuni and C. coli isolates from young storks was as follows: to ciprofloxacin (52.4%, 44.4%), and to tetracycline (19%, 77.8%). All of the analyzed isolates were susceptible to macrolides. The resistance to both classes of antibiotics was found in the 23.3% of Campylobacter spp. All Campylobacter spp. isolates had cadF gene and flaA gene responsible for adherence and motility. CdtB gene associated with toxin production was present in 88.9% of C. coli isolates and 57.1% of C. jejuni isolates. The iam marker was found more often in C. coli strains (55.6%) compared to C. jejuni isolates (42.9%). Our results confirm the prevalence of Campylobacter spp. in the white stork in natural conditions and, because it lives in open farmlands with access to marshy wetlands, the environmental sources such as water reservoirs and soil-water can be contaminated from white stork feces and the pathogens can be widely disseminated. We can thus conclude that Campylobacter spp. may easily be transmitted to waterfowl, other birds, and humans via its environmental sources and/or by immediate contact. PMID:25456607

  2. Prevalence, virulence, and antimicrobial resistance of Campylobacter jejuni and Campylobacter coli in white stork Ciconia ciconia in Poland.

    PubMed

    Szczepańska, Bernadeta; Kamiński, Piotr; Andrzejewska, Małgorzata; Śpica, Dorota; Kartanas, Edmund; Ulrich, Werner; Jerzak, Leszek; Kasprzak, Mariusz; Bocheński, Marcin; Klawe, Jacek J

    2015-01-01

    The aim of this study was to investigate the role of white stork Ciconia ciconia as a potential reservoir of Campylobacter spp. Antimicrobial resistance and the presence of putative virulence genes of the isolates were also examined. A total of 398 white stork chicks sampled in Western Poland in habitats with high density of breeding were examined. Rectal swabs were collected during breeding season 2009-2012 from storks developing in a relatively pure environment (Odra meadows), in polluted areas (a copper mining-smelting complex), and in suburbs. Of the anal swabs collected, 7.6% were positive for Campylobacter among chicks (5.3% samples positive for C. jejuni and 2.3% samples positive for C. coli). Samples from polluted areas had the highest prevalence of Campylobacter (12.2%). The prevalence of resistance among C. jejuni and C. coli isolates from young storks was as follows: to ciprofloxacin (52.4%, 44.4%), and to tetracycline (19%, 77.8%). All of the analyzed isolates were susceptible to macrolides. The resistance to both classes of antibiotics was found in the 23.3% of Campylobacter spp. All Campylobacter spp. isolates had cadF gene and flaA gene responsible for adherence and motility. CdtB gene associated with toxin production was present in 88.9% of C. coli isolates and 57.1% of C. jejuni isolates. The iam marker was found more often in C. coli strains (55.6%) compared to C. jejuni isolates (42.9%). Our results confirm the prevalence of Campylobacter spp. in the white stork in natural conditions and, because it lives in open farmlands with access to marshy wetlands, the environmental sources such as water reservoirs and soil-water can be contaminated from white stork feces and the pathogens can be widely disseminated. We can thus conclude that Campylobacter spp. may easily be transmitted to waterfowl, other birds, and humans via its environmental sources and/or by immediate contact.

  3. Impact of UV and Peracetic Acid Disinfection on the Prevalence of Virulence and Antimicrobial Resistance Genes in Uropathogenic Escherichia coli in Wastewater Effluents

    PubMed Central

    Biswal, Basanta Kumar; Khairallah, Ramzi; Bibi, Kareem; Mazza, Alberto; Gehr, Ronald; Masson, Luke

    2014-01-01

    Wastewater discharges may increase the populations of pathogens, including Escherichia coli, and of antimicrobial-resistant strains in receiving waters. This study investigated the impact of UV and peracetic acid (PAA) disinfection on the prevalence of virulence and antimicrobial resistance genes in uropathogenic Escherichia coli (UPEC), the most abundant E. coli pathotype in municipal wastewaters. Laboratory disinfection experiments were conducted on wastewater treated by physicochemical, activated sludge, or biofiltration processes; 1,766 E. coli isolates were obtained for the evaluation. The target disinfection level was 200 CFU/100 ml, resulting in UV and PAA doses of 7 to 30 mJ/cm2 and 0.9 to 2.0 mg/liter, respectively. The proportions of UPECs were reduced in all samples after disinfection, with an average reduction by UV of 55% (range, 22% to 80%) and by PAA of 52% (range, 11% to 100%). Analysis of urovirulence genes revealed that the decline in the UPEC populations was not associated with any particular virulence factor. A positive association was found between the occurrence of urovirulence and antimicrobial resistance genes (ARGs). However, the changes in the prevalence of ARGs in potential UPECs were different following disinfection, i.e., UV appears to have had no effect, while PAA significantly reduced the ARG levels. Thus, this study showed that both UV and PAA disinfections reduced the proportion of UPECs and that PAA disinfection also reduced the proportion of antimicrobial resistance gene-carrying UPEC pathotypes in municipal wastewaters. PMID:24727265

  4. Impact of UV and peracetic acid disinfection on the prevalence of virulence and antimicrobial resistance genes in uropathogenic Escherichia coli in wastewater effluents.

    PubMed

    Biswal, Basanta Kumar; Khairallah, Ramzi; Bibi, Kareem; Mazza, Alberto; Gehr, Ronald; Masson, Luke; Frigon, Dominic

    2014-06-01

    Wastewater discharges may increase the populations of pathogens, including Escherichia coli, and of antimicrobial-resistant strains in receiving waters. This study investigated the impact of UV and peracetic acid (PAA) disinfection on the prevalence of virulence and antimicrobial resistance genes in uropathogenic Escherichia coli (UPEC), the most abundant E. coli pathotype in municipal wastewaters. Laboratory disinfection experiments were conducted on wastewater treated by physicochemical, activated sludge, or biofiltration processes; 1,766 E. coli isolates were obtained for the evaluation. The target disinfection level was 200 CFU/100 ml, resulting in UV and PAA doses of 7 to 30 mJ/cm(2) and 0.9 to 2.0 mg/liter, respectively. The proportions of UPECs were reduced in all samples after disinfection, with an average reduction by UV of 55% (range, 22% to 80%) and by PAA of 52% (range, 11% to 100%). Analysis of urovirulence genes revealed that the decline in the UPEC populations was not associated with any particular virulence factor. A positive association was found between the occurrence of urovirulence and antimicrobial resistance genes (ARGs). However, the changes in the prevalence of ARGs in potential UPECs were different following disinfection, i.e., UV appears to have had no effect, while PAA significantly reduced the ARG levels. Thus, this study showed that both UV and PAA disinfections reduced the proportion of UPECs and that PAA disinfection also reduced the proportion of antimicrobial resistance gene-carrying UPEC pathotypes in municipal wastewaters. PMID:24727265

  5. Prevalence of antimicrobial resistance in Acinetobacter calcoaceticus-baumannii complex in a Saudi Arabian hospital.

    PubMed

    Al-Tawfiq, Jaffar A; Mohandhas, Thangiah X

    2007-07-01

    During the period from 1998 through 2004, a total of 476 isolates of Acinetobacter calcoaceticus-baumannii complex were recovered. The organism showed high rates of resistance to ampicillin (86% of isolates), cefoxitin (89%), and nitrofurantoin (89%). The rate of resistance to imipenem was 3%; to ticarcillin-clavulanic acid, 16.5%; to gentamicin, 26%; and to ceftazidime, 38%. Multidrug resistance was observed in 14%-35.8% of Acinetobacter species isolates.

  6. Antimicrobial Drugs in Fighting against Antimicrobial Resistance

    PubMed Central

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

    2016-01-01

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

  7. Antimicrobial Drugs in Fighting against Antimicrobial Resistance.

    PubMed

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

    2016-01-01

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

  8. Effects of subtherapeutic administration of antimicrobial agents to beef cattle on the prevalence of antimicrobial resistance in Campylobacter jejuni and Campylobacter hyointestinalis.

    PubMed

    Inglis, G D; McAllister, T A; Busz, H W; Yanke, L J; Morck, D W; Olson, M E; Read, R R

    2005-07-01

    The influence of antimicrobial agents on the development of antimicrobial resistance (AMR) in Campylobacter isolates recovered from 300 beef cattle maintained in an experimental feedlot was monitored over a 315-day period (11 sample times). Groups of calves were assigned to one of the following antimicrobial treatments: chlortetracycline and sulfamethazine (CS), chlortetracycline alone (Ct), virginiamycin, monensin, tylosin phosphate, and no antimicrobial agent (i.e., control treatment). In total, 3,283 fecal samples were processed for campylobacters over the course of the experiment. Of the 2,052 bacterial isolates recovered, 92% were Campylobacter (1,518 were Campylobacter hyointestinalis and 380 were C. jejuni). None of the antimicrobial treatments decreased the isolation frequency of C. jejuni relative to the control treatment. In contrast, C. hyointestinalis was isolated less frequently from animals treated with CS and to a lesser extent from animals treated with Ct. The majority (> or =94%) of C. jejuni isolates were sensitive to ampicillin, erythromycin, and ciprofloxacin, but more isolates with resistance to tetracycline were recovered from animals fed Ct. All of the 1,500 isolates of C. hyointestinalis examined were sensitive to ciprofloxacin. In contrast, 11%, 10%, and 1% of these isolates were resistant to tetracycline, erythromycin, and ampicillin, respectively. The number of animals from which C. hyointestinalis isolates with resistance to erythromycin and tetracycline were recovered differed among the antimicrobial treatments. Only Ct administration increased the carriage rates of erythromycin-resistant isolates of C. hyointestinalis, and the inclusion of CS in the diet increased the number of animals from which tetracycline-resistant isolates were recovered. The majority of C. hyointestinalis isolates with resistance to tetracycline were obtained from cohorts within a single pen, and most of these isolates were recovered from cattle during feeding of

  9. Prevalence, species distribution and antimicrobial resistance of enterococci isolated from dogs and cats in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The contribution of dogs and cats as reservoirs of antimicrobial resistant enterococci remains largely undefined. This is increasingly important considering the possibility of transfer of bacteria from companion animals to the human host. In this study, dogs and cats from veterinary clinics were s...

  10. Prevalence, antimicrobial resistance, and virulence characteristics of mecA-encoding coagulase-negative staphylococci isolated from soft cheese in Brazil.

    PubMed

    Fontes, Cláudia Oliveira; Silva, Vânia Lúcia; de Paiva, Mayara Rodrigues Brandão; Garcia, Rafaela Alvim; Resende, Juliana Alves; Ferreira-Machado, Alessandra Barbosa; Diniz, Cláudio Galuppo

    2013-04-01

    Coagulase-negative staphylococci (CoNS), which are generally neglected as foodborne bacteria, are emerging as significant opportunistic pathogens that may be highly resistant to available antimicrobial drugs. In this study, antimicrobial susceptibility patterns, mecA gene occurrence, and virulence-associated characteristics were evaluated in CoNS isolated from soft cheese in Brazil. A total of 227 bacterial isolates were recovered from 35 cheese samples belonging to 5 batches with 7 different trademarks. The CoNS counts ranged from 10(6) to 10(7) CFU/g. High antimicrobial resistance percentages were observed for oxacillin (76.2%), penicillin (78.5%), erythromycin (67.8%), gentamicin (47.2%), clindamycin (35.7%), rifampicin (26.8%), azithromycin (14.7%), tetracycline (14.7%), levofloxacin (14.2%), and sulfamethoxazole-trimethoprim (11.9%). A low antimicrobial resistance percentage was observed for chloramphenicol (2.3%), and all of the tested bacteria were susceptible to vancomycin and linezolid. In total, a multiple antibiotic resistance (MAR) index of >0.2 was observed for 80.6% of the isolated CoNS. However, the MAR index ranged from 50% to 92.6% when only bacterial cheese isolates belonging to the same trademark were considered. Regarding to the prevalence of CoNS carrying mecA gene, 81.5% of the isolated strains were mecA(+) , and 76.2% of these were phenotypically resistant to oxacillin. Three isolates carried the enterotoxin A gene (sea), 29.5% produced biofilm in a laboratory test, and α- or ß-hemolysis were observed for 3% and 5.2%, respectively. This study highlights the extent of the antimicrobial resistance phenomenon in neglected foodborne microorganisms and the potential public health risks that are related to the consumption of CoNS-contaminated soft cheese.

  11. Prevalence and antimicrobial resistance of Campylobacter in raw milk in the selected areas of Poland.

    PubMed

    Wysok, B; Wiszniewska-Łaszczych, A; Uradziński, J; Szteyn, J

    2011-01-01

    During the recent years, an immense increase in the number of food poisoning cases in people caused by Campylobacter (C.) species has occurred. Raw milk, next to poultry meat, is considered the most frequent cause of food poisoning in people caused by the subject bacteria, although it is not always possible to isolate Campylobacter cells from the incriminated milk. Most probably this difficulty is caused by low concentration of the pathogen in milk at the level of 2/3 cells/ml although even such low concentration represents risk to human health. The present study was aimed at determining the occurence of Campylobacter bacteria in milk originating from selected regions of Poland. The isolation method applied in this work was effective in recovering as few as 0.1 cell of Campylobacter per g of food. Among 150 bulk milk samples tested, Campylobacter spp. was isolated from 7 (4.6%) ones. The biochemical identification of the isolated strains conducted by means of conventional biochemical tests as well as by applying the API - Campy tests revealed that all the isolates belonged to the C. jejuni species. Determination of resistance to antibiotics was performed by means of the diffusion disks method for the following antibiotics: gentamicin, ciprofloxacin, ampicillin, chloramphenicol, erythromycin, doxycyclin and tetracycline. Among 7 isolates tested, all were susceptible to ampicillin, chloramphenicol, erythromycin and gentamicin, 28.5% to doxycyclin and 14.2% to tetracycline and ciprofloxacin.

  12. Prevalence and antimicrobial resistance of Campylobacter in raw milk in the selected areas of Poland.

    PubMed

    Wysok, B; Wiszniewska-Łaszczych, A; Uradziński, J; Szteyn, J

    2011-01-01

    During the recent years, an immense increase in the number of food poisoning cases in people caused by Campylobacter (C.) species has occurred. Raw milk, next to poultry meat, is considered the most frequent cause of food poisoning in people caused by the subject bacteria, although it is not always possible to isolate Campylobacter cells from the incriminated milk. Most probably this difficulty is caused by low concentration of the pathogen in milk at the level of 2/3 cells/ml although even such low concentration represents risk to human health. The present study was aimed at determining the occurence of Campylobacter bacteria in milk originating from selected regions of Poland. The isolation method applied in this work was effective in recovering as few as 0.1 cell of Campylobacter per g of food. Among 150 bulk milk samples tested, Campylobacter spp. was isolated from 7 (4.6%) ones. The biochemical identification of the isolated strains conducted by means of conventional biochemical tests as well as by applying the API - Campy tests revealed that all the isolates belonged to the C. jejuni species. Determination of resistance to antibiotics was performed by means of the diffusion disks method for the following antibiotics: gentamicin, ciprofloxacin, ampicillin, chloramphenicol, erythromycin, doxycyclin and tetracycline. Among 7 isolates tested, all were susceptible to ampicillin, chloramphenicol, erythromycin and gentamicin, 28.5% to doxycyclin and 14.2% to tetracycline and ciprofloxacin. PMID:21957744

  13. Comparison of the prevalence of bacterial enteropathogens, potentially zoonotic bacteria and bacterial resistance to antimicrobials in organic and conventional poultry, swine and beef production: a systematic review and meta-analysis.

    PubMed

    Young, I; Rajić, A; Wilhelm, B J; Waddell, L; Parker, S; McEwen, S A

    2009-09-01

    The prevalences of zoonotic and potentially zoonotic bacteria or bacteria resistant to antimicrobials in organic and conventional poultry, swine and beef production were compared using systematic review and meta-analysis methodology. Thirty-eight articles were included in the review. The prevalence of Campylobacter was higher in organic broiler chickens at slaughter, but no difference in prevalence was observed in retail chicken. Campylobacter isolates from conventional retail chicken were more likely to be ciprofloxacin-resistant (odds ratio 9.62, 95% confidence interval 5.67-16.35). Bacteria isolated from conventional animal production exhibited a higher prevalence of resistance to antimicrobials; however, the recovery of some resistant strains was also identified in organic animal production, where there is an apparent reduced antimicrobial selection pressure. Limited or inconsistent research was identified in studies examining the prevalence of zoonotic and potentially zoonotic bacteria in other food-animal species. There is a need for further research of sufficient quality in this area.

  14. Antimicrobial use and resistance in animals.

    PubMed

    McEwen, Scott A; Fedorka-Cray, Paula J

    2002-06-01

    Food animals in the United States are often exposed to antimicrobials to treat and prevent infectious disease or to promote growth. Many of these antimicrobials are identical to or closely resemble drugs used in humans. Precise figures for the quantity of antimicrobials used in animals are not publicly available in the United States, and estimates vary widely. Antimicrobial resistance has emerged in zoonotic enteropathogens (e.g., Salmonella spp., Campylobacter spp.), commensal bacteria (e.g., Escherichia coli, enterococci), and bacterial pathogens of animals (e.g., Pasteurella, Actinobacillus spp.), but the prevalence of resistance varies. Antimicrobial resistance emerges from the use of antimicrobials in animals and the subsequent transfer of resistance genes and bacteria among animals and animal products and the environment. To slow the development of resistance, some countries have restricted antimicrobial use in feed, and some groups advocate similar measures in the United States. Alternatives to growth-promoting and prophylactic uses of antimicrobials in agriculture include improved management practices, wider use of vaccines, and introduction of probiotics. Monitoring programs, prudent use guidelines, and educational campaigns provide approaches to minimize the further development of antimicrobial resistance. PMID:11988879

  15. Pathogen prevalence and influence of composted dairy manure application on antimicrobial resistance profiles of commensal soil bacteria.

    PubMed

    Edrington, Tom S; Fox, William E; Callaway, Todd R; Anderson, Robin C; Hoffman, Dennis W; Nisbet, David J

    2009-03-01

    Composting manure, if done properly, should kill pathogenic bacteria such as Salmonella and Escherichia coli O157:H7, providing for an environmentally safe product. Over a 3-year period, samples of composted dairy manure, representing 11 composting operations (two to six samples per producer; 100 total samples), were screened for Salmonella and E. coli O157:H7 and were all culture negative. Nonpathogenic bacteria were cultured from these compost samples that could theoretically facilitate the spread of antimicrobial resistance from the dairy to compost application sites. Therefore, we collected soil samples (three samples per plot; 10 plots/treatment; 90 total samples) from rangeland that received either composted dairy manure (CP), commercial fertilizer (F), or no treatment (control, CON). Two collections were made appoximately 2 and 7 months following treatment application. Soil samples were cultured for Pseudomonas and Enterobacter and confirmed isolates subjected to antimicrobial susceptibility testing. Three species of Enterobacter (cloacae, 27 isolates; aeroginosa, two isolates; sakazakii, one isolate) and two species of Pseudomonas (aeruginosa, 11 isolates; putida, seven isolates) were identified. Five Enterobacter isolates were resistant to ampicillin and one isolate was resistant to spectinomycin. All Pseudomonas isolates were resistant to ampicillin, ceftiofur, florfenicol, sulphachloropyridazine, sulphadimethoxine, and trimethoprim/sulfamethoxazole and most isolates were resistant to chlortetracycline and spectinomycin. Pseudomonas isolates were resistant to an average of 8.6, 7.9, and 8 antibiotics for CON, CP, and F treatments, respectively. No treatment differences were observed in antimicrobial resistance patterns in any of the soil isolates examined. Results reported herein support the use of composted dairy manure as an environmentally friendly soil amendment. PMID:19105635

  16. PREVALENCE AND ANTIMICROBIAL RESISTANCE OF SALMONELLA ISOLATED FROM CARCASSES, PROCESSING FACILITIES AND THE ENVIRONMENT SURROUNDING SMALL SCALE POULTRY SLAUGHTERHOUSES IN THAILAND.

    PubMed

    Chotinun, Suwit; Rojanasthien, Suvichai; Unger, Fred; Tadee, Pakpoom; Patchanee, Prapas

    2014-11-01

    Salmonella is a major food-borne pathogen worldwide, including Thai- land, and poultry meat plays a role as a vehicle for the spread of the disease from animals to humans. The prevalence and characteristics of Salmonella isolated from 41 small scale poultry slaughterhouses in Chiang Mai, Thailand were determined during July 2011 through May 2012. Salmonella's prevalence in live poultry, car- casses, waste water, and soil around processing plants were 3.2%, 7.3%, 22.0% and 29.0%, respectively. Eighteen different serotypes were identified, the most common being Corvallis (15.2%), followed by Rissen (13.9%), Hadar (12.7%), Enteritidis (10.1%), [I. 4,5,12:i:-] (8.8%), Stanley (8.8%), and Weltevreden (8.8%). Antimicrobial susceptibility tests revealed that 68.4% of the Salmonella spp were resistant to at least one antimicrobial while 50.6% showed multiple drug resis- tance (MDR). Specifically, 44.3% of Salmonella were resistant to nalidixic acid, followed by streptomycin (41.8%), ampicillin (34.2%), tetracycline (34.2%), and sulfamethoxazole/trimethoprim (20.3%). Salmonella contamination was found in processing lines, carcasses, and in the environment around the processing sta- tions. These findings indicate that improving hygiene management in small scale poultry slaughterhouses as well as prudent use of antimicrobial drugs is urgently needed if Salmonella contamination is to be reduced.

  17. Prevalence and antimicrobial resistance of non-typhoidal Salmonella serotypes isolated from laying hens and broiler chicken farms in N'Djamena, Chad.

    PubMed

    Tabo, Djim-adjim; Diguimbaye, Colette D; Granier, Sophie A; Moury, Frédérique; Brisabois, Anne; Elgroud, Rachid; Millemann, Yves

    2013-09-27

    This study aimed at updating knowledge on the prevalence and antimicrobial resistance characteristics of Salmonella isolated from poultry in the province of N'Djamena, Chad. The results collected during this study provide the first baseline data on the prevalence of contamination by Salmonella in laying hens and broiler chicken farms in N'Djamena. All samples were collected from sixteen poultry farms over two periods of six months each: from August 2010 to January 2011 and from September 2011 to February 2012. Diagnostic methods used during this study allowed to isolate eighty four Salmonella strains, belonging to twenty seven different serotypes. The most frequent serotypes were Salmonella Colindale (19%) followed by S. Minnesota (18%) S. Havana and S. Riggil (each 6%), S. Kottbus and S. Amager (4.7%), S. Idikan, Mississipi, and Muenchen (3.6%). Other serotypes were poorly represented. The majority of these serotypes were susceptible to all antibiotics tested (CLSI Standards), except some S. Colindale isolates that exhibited a decreased susceptibility to fluoroquinolones, S. Limete resistant to three antibiotics and S. Minnesota isolates resistant to five different antimicrobial classes. The different serotypes and antibiotic resistance profiles that were observed highlight the substantial diversity of Salmonella in Chad, the contribution of avian isolates to human salmonellosis and Salmonella's capacity to colonize all types of environment worldwide.

  18. Five-Year Antimicrobial Resistance Patterns of Urinary Escherichia coli at an Australian Tertiary Hospital: Time Series Analyses of Prevalence Data

    PubMed Central

    Fasugba, Oyebola; Mitchell, Brett G.; Mnatzaganian, George; Das, Anindita; Collignon, Peter; Gardner, Anne

    2016-01-01

    This study describes the antimicrobial resistance temporal trends and seasonal variation of Escherichia coli (E. coli) urinary tract infections (UTIs) over five years, from 2009 to 2013, and compares prevalence of resistance in hospital- and community-acquired E. coli UTI. A cross sectional study of E. coli UTIs from patients attending a tertiary referral hospital in Canberra, Australia was undertaken. Time series analysis was performed to illustrate resistance trends. Only the first positive E. coli UTI per patient per year was included in the analysis. A total of 15,022 positive cultures from 8724 patients were identified. Results are based on 5333 first E. coli UTIs, from 4732 patients, of which 84.2% were community-acquired. Five-year hospital and community resistance rates were highest for ampicillin (41.9%) and trimethoprim (20.7%). Resistance was lowest for meropenem (0.0%), nitrofurantoin (2.7%), piperacillin-tazobactam (2.9%) and ciprofloxacin (6.5%). Resistance to amoxycillin-clavulanate, cefazolin, gentamicin and piperacillin-tazobactam were significantly higher in hospital- compared to community-acquired UTIs (9.3% versus 6.2%; 15.4% versus 9.7%; 5.2% versus 3.7% and 5.2% versus 2.5%, respectively). Trend analysis showed significant increases in resistance over five years for amoxycillin-clavulanate, trimethoprim, ciprofloxacin, nitrofurantoin, trimethoprim-sulphamethoxazole, cefazolin, ceftriaxone and gentamicin (P<0.05, for all) with seasonal pattern observed for trimethoprim resistance (augmented Dickey-Fuller statistic = 4.136; P = 0.006). An association between ciprofloxacin resistance, cefazolin resistance and ceftriaxone resistance with older age was noted. Given the relatively high resistance rates for ampicillin and trimethoprim, these antimicrobials should be reconsidered for empirical treatment of UTIs in this patient population. Our findings have important implications for UTI treatment based on setting of acquisition. PMID:27711250

  19. Antimicrobial Resistance in Agriculture

    PubMed Central

    Thanner, Sophie; Drissner, David

    2016-01-01

    ABSTRACT In this article, the current knowledge and knowledge gaps in the emergence and spread of antimicrobial resistance (AMR) in livestock and plants and importance in terms of animal and human health are discussed. Some recommendations are provided for generation of the data required in order to develop risk assessments for AMR within agriculture and for risks through the food chain to animals and humans. PMID:27094336

  20. Strategies to Combat Antimicrobial Resistance

    PubMed Central

    Uchil, Rajesh R; Kohli, Gurdeep Singh; Katekhaye, Vijay M

    2014-01-01

    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. PMID:25177596

  1. Prevalence and antimicrobial resistance of porcine O157 and non-O157 Shiga toxin-producing Escherichia coli from India.

    PubMed

    Rajkhowa, Swaraj; Sarma, Dilip Kumar

    2014-08-01

    The aims of this study were to determine the prevalence of Shiga toxin-producing Escherichia coli (STEC) strains in pigs as a possible STEC reservoir in India as well as to characterize the STEC strains and to determine the antimicrobial resistance pattern of the strains. A total of 782 E. coli isolates from clinically healthy (n = 473) and diarrhoeic piglets (309) belonging to major pig-producing states of India were screened by the polymerase chain reaction (PCR) assay for the presence of virulence genes characteristic for STEC, that is, Shiga toxin-producing gene(s) (stx1, stx2), intimin (eae), enterohemolysin (hlyA) and STEC autoagglutinating adhesin (Saa). Overall STEC were detected in 113 (14.4%) piglets, and the prevalence of E. coli O157 and non-O157 STEC were 4 (0.5%) and 109 (13.9%), respectively. None of the O157 STEC isolates carried gene encoding for H7 antigen (fliCh7). The various combinations of virulence genes present in the strains studied were stx1 in 4.6%, stx1 in combination with stx2 gene in 5.1%, stx1 in combination with stx2 and ehxA in 0.6%, stx1 in combination with stx2 and eae in 0.2% and stx2 alone in 3.7%. All STEC isolates were found negative for STEC autoagglutinating adhesin (Saa). The number of STEC isolates which showed resistance to antimicrobials such as ampicillin, tetracycline, streptomycin, lincomycin, nalidixic acid, sulfadiazine, penicillin, gentamicin, kanamycin and ceftriaxone were 100, 99, 98, 97, 95, 94, 92, 88, 85 and 85, respectively. Ninety-seven isolates showed resistance to more than 2 antimicrobials, and 8 resistance groups (R1 to R8) were observed. This study demonstrates that pigs in India harbour both O157 and non-O157 STEC, and this may pose serious public health problems in future.

  2. Prevalence and Antimicrobial Resistance in Salmonella and Shigella Species Isolated from Outpatients, Jimma University Specialized Hospital, Southwest Ethiopia.

    PubMed

    Lamboro, Tesfahun; Ketema, Tsige; Bacha, Ketema

    2016-01-01

    This study was designed to investigate the prevalence of Salmonella and Shigella among outpatients in Jimma University Specialized Hospital, Southwest Ethiopia. Cross-sectional study was conducted involving a total of 176 outpatients. Stool specimens from both adult and pediatric outpatients were collected and analyzed for the presence of presumptive Salmonella and Shigella colonies followed by confirmation by biochemical tests. Pure cultures of Salmonella and Shigella species were further subjected to test for antibiotic resistance against the commonly used antibiotics. Furthermore, growth potential of the isolates in selected foods items was assessed following standard procedures. The result indicated that the prevalence of Salmonella and Shigella among outpatients in the study area was 19 (10.8%) and 2 (1.1%), respectively. In addition, Salmonella species were resistant to ampicillin (100%) followed by tetracycline (47.4%) and nalidixic acid (26.3%) while Shigella species were highly resistant to ampicillin and tetracycline (100%, each). Multidrug resistance towards maximum of four drugs was observed in both pathogens. The pathogens were observed growing to their infective dose within 24 hours. In conclusion, Salmonella and Shigella are still among microbes of public health importance in the study area. Thus, this calls for frequent monitory and evaluation of their prevalence and drug resistance patterns besides awareness development on water sanitation and hygienic food handling practices to the public at large.

  3. Prevalence and Antimicrobial Resistance in Salmonella and Shigella Species Isolated from Outpatients, Jimma University Specialized Hospital, Southwest Ethiopia

    PubMed Central

    Lamboro, Tesfahun; Bacha, Ketema

    2016-01-01

    This study was designed to investigate the prevalence of Salmonella and Shigella among outpatients in Jimma University Specialized Hospital, Southwest Ethiopia. Cross-sectional study was conducted involving a total of 176 outpatients. Stool specimens from both adult and pediatric outpatients were collected and analyzed for the presence of presumptive Salmonella and Shigella colonies followed by confirmation by biochemical tests. Pure cultures of Salmonella and Shigella species were further subjected to test for antibiotic resistance against the commonly used antibiotics. Furthermore, growth potential of the isolates in selected foods items was assessed following standard procedures. The result indicated that the prevalence of Salmonella and Shigella among outpatients in the study area was 19 (10.8%) and 2 (1.1%), respectively. In addition, Salmonella species were resistant to ampicillin (100%) followed by tetracycline (47.4%) and nalidixic acid (26.3%) while Shigella species were highly resistant to ampicillin and tetracycline (100%, each). Multidrug resistance towards maximum of four drugs was observed in both pathogens. The pathogens were observed growing to their infective dose within 24 hours. In conclusion, Salmonella and Shigella are still among microbes of public health importance in the study area. Thus, this calls for frequent monitory and evaluation of their prevalence and drug resistance patterns besides awareness development on water sanitation and hygienic food handling practices to the public at large. PMID:27642307

  4. Prevalence and Antimicrobial Resistance in Salmonella and Shigella Species Isolated from Outpatients, Jimma University Specialized Hospital, Southwest Ethiopia.

    PubMed

    Lamboro, Tesfahun; Ketema, Tsige; Bacha, Ketema

    2016-01-01

    This study was designed to investigate the prevalence of Salmonella and Shigella among outpatients in Jimma University Specialized Hospital, Southwest Ethiopia. Cross-sectional study was conducted involving a total of 176 outpatients. Stool specimens from both adult and pediatric outpatients were collected and analyzed for the presence of presumptive Salmonella and Shigella colonies followed by confirmation by biochemical tests. Pure cultures of Salmonella and Shigella species were further subjected to test for antibiotic resistance against the commonly used antibiotics. Furthermore, growth potential of the isolates in selected foods items was assessed following standard procedures. The result indicated that the prevalence of Salmonella and Shigella among outpatients in the study area was 19 (10.8%) and 2 (1.1%), respectively. In addition, Salmonella species were resistant to ampicillin (100%) followed by tetracycline (47.4%) and nalidixic acid (26.3%) while Shigella species were highly resistant to ampicillin and tetracycline (100%, each). Multidrug resistance towards maximum of four drugs was observed in both pathogens. The pathogens were observed growing to their infective dose within 24 hours. In conclusion, Salmonella and Shigella are still among microbes of public health importance in the study area. Thus, this calls for frequent monitory and evaluation of their prevalence and drug resistance patterns besides awareness development on water sanitation and hygienic food handling practices to the public at large. PMID:27642307

  5. Prevalence and Antimicrobial Resistance in Salmonella and Shigella Species Isolated from Outpatients, Jimma University Specialized Hospital, Southwest Ethiopia

    PubMed Central

    Lamboro, Tesfahun; Bacha, Ketema

    2016-01-01

    This study was designed to investigate the prevalence of Salmonella and Shigella among outpatients in Jimma University Specialized Hospital, Southwest Ethiopia. Cross-sectional study was conducted involving a total of 176 outpatients. Stool specimens from both adult and pediatric outpatients were collected and analyzed for the presence of presumptive Salmonella and Shigella colonies followed by confirmation by biochemical tests. Pure cultures of Salmonella and Shigella species were further subjected to test for antibiotic resistance against the commonly used antibiotics. Furthermore, growth potential of the isolates in selected foods items was assessed following standard procedures. The result indicated that the prevalence of Salmonella and Shigella among outpatients in the study area was 19 (10.8%) and 2 (1.1%), respectively. In addition, Salmonella species were resistant to ampicillin (100%) followed by tetracycline (47.4%) and nalidixic acid (26.3%) while Shigella species were highly resistant to ampicillin and tetracycline (100%, each). Multidrug resistance towards maximum of four drugs was observed in both pathogens. The pathogens were observed growing to their infective dose within 24 hours. In conclusion, Salmonella and Shigella are still among microbes of public health importance in the study area. Thus, this calls for frequent monitory and evaluation of their prevalence and drug resistance patterns besides awareness development on water sanitation and hygienic food handling practices to the public at large.

  6. [Neruda and antimicrobial resistance].

    PubMed

    Cotera, Alejandro

    2011-07-01

    Antimicrobial resistance has been a problem in medicine, since their incorporation to clinical practice. Numerous papers have been written on the subject. The analysis of two poems by Pablo Neruda "How much does a man live" and "Larynx", included in the volume "Estravagario" and published for the first time in 1957 and 1958, give us an incredible revelation about the concept of resistance. In these poems aureomycin, the first antimicrobial of the family of tetracyclines, was included as a poetic figure and the therapeutic action of antimicrobials was described. "Never so much bugs died I tons of them fell I but the few that remained olive I manifested their perversity". These writings incorporated novel concepts, even for physicians of that time and described the closeness of death that a patient may perceive during the course of a given disease. The capacity of Pablo Neruda to extract the essence of situations and to anticipate to conditions that only years later became clinically relevant problems, is noteworthy. PMID:22051837

  7. [Neruda and antimicrobial resistance].

    PubMed

    Cotera, Alejandro

    2011-07-01

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

  8. Identification and antimicrobial resistance prevalence of pathogenic Escherichia coli strains from treated wastewater effluents in Eastern Cape, South Africa.

    PubMed

    Adefisoye, Martins A; Okoh, Anthony I

    2016-02-01

    Antimicrobial resistance (AMR) is a global problem impeding the effective prevention/treatment of an ever-growing array of infections caused by pathogens; a huge challenge threatening the achievements of modern medicine. In this paper, we report the occurrence of multidrug resistance (MDR) in Escherichia coli strains isolated from discharged final effluents of two wastewater treatment facilities in the Eastern Cape Province of South Africa. Standard disk diffusion method was employed to determine the antibiotic susceptibility profile of 223 polymerase chain reaction (PCR)-confirmed E. coli isolates against 17 common antibiotics in human therapy and veterinary medicine. Seven virulence associated and fourteen antibiotic resistance genes were also evaluated by molecular methods. Molecular characterization revealed five pathotypes of E. coli in the following proportions: enterotoxigenic ETEC (1.4%), enteropathogenic EPEC (7.6%), enteroaggregative EAEC (7.6%), neonatal meningitis (NMEC) (14.8%), uropathogenic (41.7%), and others (26.9%). Isolates showed varying (1.7-70.6%) degrees of resistance to 15 of the test antibiotics. Multidrug resistance was exhibited by 32.7% of the isolates, with the commonest multiple antibiotic-resistant phenotype (MARP) being AP-T-CFX (12 isolates), while multiple antibiotic-resistant indices (MARI) estimated are 0.23 (Site 1) and 0.24 (Site 2). Associated antibiotic resistance genes detected in the isolates include: strA (88.2%), aadA (52.9%), cat I (15%), cmlA1 (4.6%), blaTEM (56.4%), tetA (30.4%), tetB (28.4%), tetC (42.2%), tetD (50%), tetK (11.8%), and tetM (68.6%). We conclude that municipal wastewater effluents are important reservoirs for the dissemination of potentially pathogenic E. coli (and possibly other pathogens) and antibiotic resistance genes in the aquatic milieu of the Eastern Cape and a risk to public health.

  9. Prevalence, Enumeration, Serotypes, and Antimicrobial Resistance Phenotypes of Salmonella enterica Isolates from Carcasses at Two Large United States Pork Processing Plants

    PubMed Central

    Brichta-Harhay, Dayna M.; Kalchayanand, Norasak; Bosilevac, Joseph M.; Shackelford, Steven D.; Wheeler, Tommy L.; Koohmaraie, Mohammad

    2012-01-01

    The objective of this study was to characterize Salmonella enterica contamination on carcasses in two large U.S. commercial pork processing plants. The carcasses were sampled at three points, before scalding (prescald), after dehairing/polishing but before evisceration (preevisceration), and after chilling (chilled final). The overall prevalences of Salmonella on carcasses at these three sampling points, prescald, preevisceration, and after chilling, were 91.2%, 19.1%, and 3.7%, respectively. At one of the two plants, the prevalence of Salmonella was significantly higher (P < 0.01) for each of the carcass sampling points. The prevalences of carcasses with enumerable Salmonella at prescald, preevisceration, and after chilling were 37.7%, 4.8%, and 0.6%, respectively. A total of 294 prescald carcasses had Salmonella loads of >1.9 log CFU/100 cm2, but these carcasses were not equally distributed between the two plants, as 234 occurred at the plant with higher Salmonella prevalences. Forty-one serotypes were identified on prescald carcasses with Salmonella enterica serotypes Derby, Typhimurium, and Anatum predominating. S. enterica serotypes Typhimurium and London were the most common of the 24 serotypes isolated from preevisceration carcasses. The Salmonella serotypes Johannesburg and Typhimurium were the most frequently isolated serotypes of the 9 serotypes identified from chilled final carcasses. Antimicrobial susceptibility was determined for selected isolates from each carcass sampling point. Multiple drug resistance (MDR), defined as resistance to three or more classes of antimicrobial agents, was identified for 71.2%, 47.8%, and 77.5% of the tested isolates from prescald, preevisceration, and chilled final carcasses, respectively. The results of this study indicate that the interventions used by pork processing plants greatly reduce the prevalence of Salmonella on carcasses, but MDR Salmonella was isolated from 3.2% of the final carcasses sampled. PMID:22327585

  10. Prevalence, serotype diversity, and antimicrobial resistance of Salmonella in imported shipments of spice offered for entry to the United States, FY2007-FY2009.

    PubMed

    Van Doren, Jane M; Kleinmeier, Daria; Hammack, Thomas S; Westerman, Ann

    2013-06-01

    In response to increased concerns about spice safety, the U.S. FDA initiated research to characterize the prevalence of Salmonella in imported spices. Shipments of imported spices offered for entry to the United Sates were sampled during the fiscal years 2007-2009. The mean shipment prevalence for Salmonella was 0.066 (95% CI 0.057-0.076). A wide diversity of Salmonella serotypes was isolated from spices; no single serotype constituted more than 7% of the isolates. A small percentage of spice shipments were contaminated with antimicrobial-resistant Salmonella strains (8.3%). Trends in shipment prevalence for Salmonella associated with spice properties, extent of processing, and export country, were examined. A larger proportion of shipments of spices derived from fruit/seeds or leaves of plants were contaminated than those derived from the bark/flower of spice plants. Salmonella prevalence was larger for shipments of ground/cracked capsicum and coriander than for shipments of their whole spice counterparts. No difference in prevalence was observed between shipments of spice blends and non-blended spices. Some shipments reported to have been subjected to a pathogen reduction treatment prior to being offered for U.S. entry were found contaminated. Statistical differences in Salmonella shipment prevalence were also identified on the basis of export country.

  11. Antimicrobial resistance patterns and prevalence of class 1 and 2 integrons in Shigella flexneri and Shigella sonnei isolated in Uzbekistan

    PubMed Central

    2010-01-01

    Background Shigella is a frequent cause of bacterial dysentery in the developing world. Treatment with effective antibiotics is recommended for shigellosis, but options become limited due to globally emerging resistance. One of the mechanisms for the development of resistance utilizes integrons. This study described the antibiotic susceptibility and the presence of class 1 and 2 integrons in S. flexneri and S. sonnei isolated in Uzbekistan. Results We studied 31 isolates of S. flexneri and 21 isolates of S. sonnei isolated in Uzbekistan between 1992 and 2007 for the susceptibility or resistance to ampicillin (Am), chloramphenicol (Cl), tetracycline (Te), co-trimoxazole (Sxt), kanamycin (Km), streptomycin (Str), gentamicin (Gm), cefazolin (Czn), cefoperazone (Cpr), cefuroxime (Cur), ceftazidime (Ctz), nalidixic acid (NA) and ciprofloxacin (Cip). Am/Str/Cl/Te and Am/Str/Cl/Te/Sxt resistance patterns were found most frequently in S. flexneri. Single isolates were resistant to aminoglycoside, quinolones and cephalosporins. The resistance patterns were different in the two species. Integrons were detected in 93.5% of S. flexneri (29/31) and 81.0% of S. sonnei (17/21) isolates. In addition, 61.3% of S. flexneri (19/31) isolates and 19.0% of S. sonnei (4/21) isolates carried both classes of integrons. In 29.0% of S. flexneri (9/31) isolates, only class 1 integrons were identified. In S. flexneri isolates, the presence of class 1 integrons was associated with resistance to ampicillin and chloramphenicol. Only Class 2 integrons were present in 61.9% of S. sonnei (13/21) isolates. Conclusions Our study documents antibiotic resistance among Shigella spp. in Uzbekistan. Ninety percent of Shigella strains were resistant to previously used antibiotics. Differences among S. flexneri and S. sonnei isolates in patterns of antimicrobial resistance to routinely used shigellosis antibiotics were observed. The majority of S. flexneri were resistant to ampicillin, chloramphenicol

  12. How to fight antimicrobial resistance.

    PubMed

    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.

  13. The prevalence of verocytotoxin-producing Escherichia coli and antimicrobial resistance patterns of nonverocytotoxin-producing Escherichia coli and Salmonella in Ontario broiler chickens.

    PubMed Central

    Irwin, R J; McEwen, S A; Clarke, R C; Meek, A H

    1989-01-01

    The prevalence of verocytotoxin-producing Escherichia coli and Salmonella in Ontario broiler chickens was determined by culturing cloacal samples from 500 individual birds selected from 50 poultry farms. Resistance to antimicrobials was determined for each of the isolates. In addition, abattoir and farm-level management data were obtained to evaluate variables that may be considered risk factors for infection. The variables selected included: Percentage of birds condemned at slaughter, percentage of birds dead-on-arrival, bird weight, truck number, farm size, hatchery source, litter source and type, feed source, mortality levels, type of water drinker, water sanitization, down time, barn clean out and history of antibiotic treatment. None of the cloacal samples revealed the presence of verocytotoxin-producing E. coli, though 19/500 (3.8%) contained Salmonella organisms. Nine different Salmonella serotypes were isolated; the most common being S. hadar, S. heidelberg and S. mbandaka. Resistance to tetracycline and streptomycin was common among Salmonella (63%) and E. coli (25.2%) isolates. Resistance to two or more antimicrobials occurred in 420/500 (84%) of the E. coli isolates. No statistically significant associations between abattoir or farm-level management variables and the Salmonella-status of farms were demonstrated. PMID:2686829

  14. Antimicrobial resistance status and prevalence rates of extended spectrum beta-lactamase producers isolated from a mixed human population

    PubMed Central

    Afunwa, Ruth A.; Odimegwu, Damian C.; Iroha, Romanus I.; Esimone, Charles O.

    2011-01-01

    Owing to the increasing epidemiological and therapeutic challenges associated with infections due to ESBL producers, ESBL prevalence rate among some bacteria isolates from healthy and non-healthy human population in a metropolitan Nigerian setting was evaluated. A total of one hundred and forty-five (145) bacteria strains were isolated from a total of four hundred and sixty (460) samples collected from urine, wound, throat and anal swabs of 220 healthy volunteers in the community and from 240 patients in 2 secondary and 2 tertiary hospitals (altogether, 4) in Enugu metropolis. The presumptive confirmatory test used for ESBL detection was the Double Disc Synergy Test (DDST) method. Conjugation and plasmid curing studies were also done for resistance factor determination. Of the 145 isolates, 20 were ESBL producers with 35% of these ESBL producers being of community origin and 65% from hospitals. This translates to 4.8% and 9% incidences (comparably higher than established prevalence of 4.4% and 7.5 respectively) for community and hospital infections respectively. The ESBL isolates showed high resistance to tetracycline, gentamicin, pefloxacin, ceftriaxone, cefuroxime, ciprofloxacin and Augmentin® (Amoxicilin and clavulanic acid combination). Conjugation studies for Resistance plasmid transfer showed non-transference of resistance determinants between the ESBL transconjugants and recipient strains. Correspondingly, the plasmid curing studies revealed that the acridine orange could not effect a cure on the isolates as they still retained high resistance to the antibiotics after the treatment. This study confirms the growing incidences/pool of ESBL strains in Nigeria and call for widespread and continuous monitoring towards an effective management of the potential therapeutic hurdle posed by this trend. PMID:21619555

  15. Antimicrobial resistance status and prevalence rates of extended spectrum beta-lactamase (ESBL) producers isolated from a mixed human population.

    PubMed

    Afunwa, Ruth A; Odimegwu, Damian C; Iroha, Romanus I; Esimone, Charles O

    2011-05-01

    Owing to the increasing epidemiological and therapeutic challenges associated with infections due to ESBL producers, ESBL prevalence rate among some bacteria isolates from healthy and non-healthy human population in a metropolitan Nigerian setting was evaluated. A total of one hundred and forty-five (145) bacteria strains were isolated from a total of four hundred and sixty (460) samples collected from urine, wound, throat and anal swabs of 220 healthy volunteers in the community and from 240 patients in 2 secondary and 2 tertiary hospitals (altogether, 4) in Enugu metropolis. The presumptive confirmatory test used for ESBL detection was the Double Disc Synergy Test (DDST) method. Conjugation and plasmid curing studies were also done for resistance factor determination. Of the 145 isolates, 20 were ESBL producers with 35% of these ESBL producers being of community origin and 65% from hospitals. This translates to 4.8% and 9% incidences (comparably higher than established prevalence of 4.4% and 7.5 respectively) for community and hospital infections respectively. The ESBL isolates showed high resistance to tetracycline, gentamicin, pefloxacin, ceftriaxone, cefuroxime, ciprofloxacin and Augmentin(®) (Amoxicilin and clavulanic acid combination). Conjugation studies for Resistance plasmid transfer showed non-transference of resistance determinants between the ESBL transconjugants and recipient strains. Correspondingly, the plasmid curing studies revealed that the acridine orange could not effect a cure on the isolates as they still retained high resistance to the antibiotics after the treatment. This study confirms the growing incidences/pool of ESBL strains in Nigeria and call for widespread and continuous monitoring towards an effective management of the potential therapeutic hurdle posed by this trend.

  16. Prevalence and patterns of antimicrobial resistance among Escherichia coli isolated from Zambian dairy cattle across different production systems

    PubMed Central

    Mainda, Geoffrey; Bessell, Paul B.; Muma, John B.; McAteer, Sean P.; Chase-Topping, Margo E.; Gibbons, James; Stevens, Mark P.; Gally, David L.; deC. Bronsvoort, Barend M.

    2015-01-01

    This study focused on the use of antibiotics on small, medium and commercial-sized dairy farms in the central region of Zambia and its relationship to antibiotic resistance in Escherichia coli. A stratified random sample of 104 farms was studied, representing approximately 20% of all dairy farms in the region. On each farm, faecal samples were collected from a random sample of animals and a standardised questionnaire on the usage of antibiotics was completed. An E. coli isolate was obtained from 98.67% (371/376) of the sampled animals and tested for resistance to six classes of antibiotics. The estimated prevalence of resistance across the different farming systems was: tetracycline (10.61; 95%CI: 7.40–13.82), ampicillin (6.02; 95%CI: 3.31–8.73), sulfamethoxazole/ trimethoprim (4.49; 95%CI: 2.42–6.56), cefpodoxime (1.91; 95%CI: 0.46–3.36), gentamicin (0.89; 95%CI: 0.06–1.84) and ciprofloxacin (0%). Univariate analyses indicated certain diseases, exotic breeds, location, farm size and certain management practices as risk factors for detection of resistance, whereas multivariate analyses showed an association with lumpy skin disease and a protective effect for older animals (>25 months). This study has provided novel insights into the drivers of antibiotic use and their association with antibiotic resistance in an under-studied region of Southern Africa. PMID:26211388

  17. Quantifying antimicrobial resistance at veal calf farms.

    PubMed

    Bosman, Angela B; Wagenaar, Jaap A; Wagenaar, Jaap; Stegeman, Arjan; Vernooij, Hans; Mevius, Dik

    2012-01-01

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

  18. Effect of heifer-raising practices on E. coli antimicrobial resistance and Salmonella prevalence in heifer raisers

    PubMed Central

    PEREIRA, R. V.; SILER, J. D.; CUMMINGS, K. J.; DAVIS, M. A.; WARNICK, L. D.

    2016-01-01

    SUMMARY Although cattle movement and commingling play an important role in the inter-herd transmission of pathogens, little is known about the effect of commingling of heifers at raising operations. The objective of this study was to compare the resistance of E. coli and prevalence of Salmonella from pooled faecal pats of heifers raised off-farm at multi-source raisers (MULTI) that raised heifers from at least two farms compared with on-farm raisers (HOME), with heifers from only that farm. MULTI faecal pat samples were collected from pens with animals that had arrived at the farm within the previous 2 months (AP) and from animals that would be departing the heifer raiser in 2–3 months (DP). Corresponding age sampling was conducted at HOME raisers. Odds of ampicillin resistance were 3.0 times greater in E. coli collected from MULTI compared to HOME raisers. E. coli from AP pens had significantly (P < 0.05) higher odds of resistance to ampicillin, neomycin, streptomycin, and tetracycline compared to DP pens. Salmonella recovery was not significantly different between heifer-raising systems (P = 0.3). Heifer-raising system did not have a major overall impact on selection of resistant E. coli, which was strongly affected by the age of the animals sampled. PMID:25904042

  19. Effect of heifer-raising practices on E. coli antimicrobial resistance and Salmonella prevalence in heifer raisers.

    PubMed

    Pereira, R V; Siler, J D; Cummings, K J; Davis, M A; Warnick, L D

    2015-11-01

    Although cattle movement and commingling play an important role in the inter-herd transmission of pathogens, little is known about the effect of commingling of heifers at raising operations. The objective of this study was to compare the resistance of E. coli and prevalence of Salmonella from pooled faecal pats of heifers raised off-farm at multi-source raisers (MULTI) that raised heifers from at least two farms compared with on-farm raisers (HOME), with heifers from only that farm. MULTI faecal pat samples were collected from pens with animals that had arrived at the farm within the previous 2 months (AP) and from animals that would be departing the heifer raiser in 2-3 months (DP). Corresponding age sampling was conducted at HOME raisers. Odds of ampicillin resistance were 3·0 times greater in E. coli collected from MULTI compared to HOME raisers. E. coli from AP pens had significantly (P < 0·05) higher odds of resistance to ampicillin, neomycin, streptomycin, and tetracycline compared to DP pens. Salmonella recovery was not significantly different between heifer-raising systems (P = 0·3). Heifer-raising system did not have a major overall impact on selection of resistant E. coli, which was strongly affected by the age of the animals sampled.

  20. Antimicrobial resistance gene distribution: a socioeconomic and sociocultural perspective

    PubMed Central

    Ojo, Kayode K.; Sapkota, Amy R.; Ojo, Tokunbo B.; Pottinger, Paul S.

    2008-01-01

    The appearance of resistance to many first-line antimicrobial agents presents a critical challenge to the successful treatment of bacterial infections. Antimicrobial resistant bacteria and resistance genes are globally distributed, but significant variations in prevalence have been observed in different geographical regions. This article discusses possible relationships between socioeconomic and sociocultural factors and regional differences in the prevalence of antibiotic-resistant bacteria and their associated resistance genes. Findings indicate that the few studies that have been conducted to understand relationships between socioeconomic and sociocultural factors and antimicrobial resistance have focused on patterns of phenotypic antibiotic resistance. Yet, a critical need exists for molecular studies of human influences on bacterial resistance and adaptation. We propose that the results of these studies, coupled with well-coordinated culturally appropriate interventions that address specific socioeconomic and sociocultural needs may be necessary to reduce the scourge of antimicrobial resistance in both developing and developed countries. PMID:20204098

  1. Engineering Antimicrobials Refractory to Resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  2. Prevalence, antimicrobial susceptibility and molecular typing of Methicillin-Resistant Staphylococcus aureus (MRSA) in bulk tank milk from southern Italy.

    PubMed

    Parisi, A; Caruso, M; Normanno, G; Latorre, L; Sottili, R; Miccolupo, A; Fraccalvieri, R; Santagada, G

    2016-09-01

    This paper assesses the prevalence of MRSA in bulk tank milk (BTM) samples from southern Italy, and the relationship between the Coagulase Positive Staphylococci count (CPS) and MRSA prevalence. Of 486 BTM samples tested, 12 samples (2.5%) resulted positive for the presence of MRSA. Great genetic diversity was found among the isolates: ST1/t127 and t174/IVa, ST5/t688/V, ST8/t unknown/IVa/V, ST45/t015/IVa, ST71/t524/V, ST88/t786/Iva, ST398/t011 and t899/IVa/V and ST2781/t1730/V. All isolates were pvl-negative and icaA positive. The majority of strains (58%) carried the ses (sec, seh, seg, seo, sem and sen) genes. All tested strains resulted susceptible to amikacin, cephalotin, cloramphenicol, gentamycin, trimethoprim - sulfamethoxazole, tobramycin and vancomycin, and variably resistant to ampicillin, oxacillin and tetracycline. No statistical association between the CPS count and MRSA detection was found in the MRSA-positive samples. Although some of the spa-types and STs detected in our survey are known to cause human infections, raw milk from Italian herds in the considered area is not a common source of MRSA. Nonetheless, it is necessary to assess the risk of foodborne infection and the risk related to the handling of milk.

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

    PubMed

    Bengtsson, Björn; Wierup, Martin

    2006-01-01

    The banned use of antimicrobial growth promoters resulted in a considerably decreased use of antimicrobials in food animal production in Sweden (65%), Denmark (47%), Norway (40%) and Finland (27%). The current prevalence of antimicrobial resistance in animal bacterial populations is also considerably lower than in some other countries in the EU. In the swine production, no or limited effect was found in the finisher production (>25 to 30 kg). Temporary negative effects occurred during the post weaning period (7-30 kg). In Denmark, the cost of production from birth to slaughter per pig produced increased by approximately 1.0 euro with a high variability between pig producers. In the broiler production the termination had no significant negative effect on animal health and welfare or on production economy. PMID:17127526

  4. Economic impact of antimicrobial resistance.

    PubMed Central

    McGowan, J. E.

    2001-01-01

    One reason antimicrobial-drug resistance is of concern is its economic impact on physicians, patients, health-care administrators, pharmaceutical producers, and the public. Measurement of cost and economic impact of programs to minimize antimicrobial-drug resistance is imprecise and incomplete. Studies to describe and evaluate the problem will have to employ new methods and be of large scale to produce information that is broadly applicable. PMID:11294725

  5. Baseline prevalence of antimicrobial resistance and subsequent infection following prostate biopsy using empirical or altered prophylaxis: A bias-adjusted meta-analysis.

    PubMed

    Roberts, Matthew J; Williamson, Deborah A; Hadway, Paul; Doi, Suhail A R; Gardiner, Robert A; Paterson, David L

    2014-04-01

    Transrectal ultrasound-guided prostate biopsy (TRUSPB) is a commonly performed urological procedure. Recent studies suggest that pre-biopsy screening for fluoroquinolone-resistant (FQ-R) pathogens may be useful in reducing post-biopsy infections. We sought to determine the baseline prevalence of fluoroquinolone (FQ) resistance in rectal flora and to investigate the relationship between pre-biopsy carriage of FQ-R pathogens and the risk of post-TRUSPB infection. Electronic databases were searched for related literature. Studies were assessed for methodological quality and comparable outcomes prior to meta-analysis (using quality- and random-effects models). Nine studies, representing 2541 patients, were included. The prevalence of FQ resistance was higher (20.4%, 95% CI 18.2-22.6%) in rectal cultures obtained following FQ-based prophylaxis compared with those obtained before (12.8%, 95% CI 10.7-15.0%). Overall infection rates in patients using empirical prophylaxis were higher (3.3%, 95% CI 2.6-4.2%) than in those using altered (targeted/protocol) regimens (0.3%, 95% CI 0-0.9%). Higher infection rates were seen in men with FQ-R rectal cultures (7.1%, 95% CI 4.0-10.5%) than in those with FQ-sensitive (FQ-S) rectal cultures (1.1%, 95% CI 0.5-1.8%). For every 14 men with FQ-R rectal cultures, one additional infection was observed compared with men with FQ-S rectal cultures. Prior FQ use and prior genitourinary infection were significant risk factors for FQ-R colonisation. FQ resistance in rectal flora is a significant predictor of post-TRUSPB infection and may require re-assessment of empirical antimicrobial prophylaxis methods. Altered prophylaxis based on rectal culturing prior to TRUSPB may reduce morbidity and potentially provide economic benefits to health services.

  6. Molecular Detection of Antimicrobial Resistance

    PubMed Central

    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

  7. Prevalence and transmission of antimicrobial resistance among Aeromonas populations from a duckweed aquaculture based hospital sewage water recycling system in Bangladesh.

    PubMed

    Rahman, Mokhlasur; Huys, Geert; Kühn, Inger; Rahman, Motiur; Möllby, Roland

    2009-10-01

    In order to investigate the influence of a duckweed aquaculture based hospital sewage water recycling plant on the prevalence and dissemination of antibiotic resistance, we made use of an existing collection of 1,315 Aeromonas isolates that were previously typed by the biochemical fingerprinting PhP-AE system. In these treatment plant, hospital raw sewage water is first collected in a settlement pond (referred to as sewage water in this study) and is then transferred to a lagoon, where the duckweed (Lemnaceae) is grown (referred to as lagoon). The duckweed is harvested and used as feed for the fish in a separate pond (referred to as fish pond). From this collection, representatives of 288 PhP types were subjected to antibiotic susceptibility testing for eight antimicrobials by broth microdilution method. The overall resistance rates among Aeromonas isolates from the treatment plant were highest for ampicillin (87%) and erythromycin (79%) followed by cephalothin (58%), nalidixic acid (52%), streptomycin (51%), tetracycline (31%), chloramphenicol (13%) and gentamicin (8%). A significantly lower prevalence of antibiotic resistance was found in Aeromonas from environmental control water, patient stool samples, duckweed and fish compared to sewage water isolates. The prevalence of resistance in the sewage water was not significantly reduced compared to the lagoon water and fish pond. Throughout the treatment system, the frequencies of resistant strains were found to diminish during the sewage water purification process, i.e. in the lagoon where sewage water is used to grow the duckweed. However, the frequency of resistant strains again increased in the fish pond where sewage grown duckweed is used for aquaculture. Among the selected isolates, two multiresistant clonal groups of Aeromonas caviae HG4 were identified that exhibited indistinguishable PhP and amplified fragment length polymorphism fingerprints and shared a common plasmid of approximately 5 kb

  8. Prevalence and transmission of antimicrobial resistance among Aeromonas populations from a duckweed aquaculture based hospital sewage water recycling system in Bangladesh.

    PubMed

    Rahman, Mokhlasur; Huys, Geert; Kühn, Inger; Rahman, Motiur; Möllby, Roland

    2009-10-01

    In order to investigate the influence of a duckweed aquaculture based hospital sewage water recycling plant on the prevalence and dissemination of antibiotic resistance, we made use of an existing collection of 1,315 Aeromonas isolates that were previously typed by the biochemical fingerprinting PhP-AE system. In these treatment plant, hospital raw sewage water is first collected in a settlement pond (referred to as sewage water in this study) and is then transferred to a lagoon, where the duckweed (Lemnaceae) is grown (referred to as lagoon). The duckweed is harvested and used as feed for the fish in a separate pond (referred to as fish pond). From this collection, representatives of 288 PhP types were subjected to antibiotic susceptibility testing for eight antimicrobials by broth microdilution method. The overall resistance rates among Aeromonas isolates from the treatment plant were highest for ampicillin (87%) and erythromycin (79%) followed by cephalothin (58%), nalidixic acid (52%), streptomycin (51%), tetracycline (31%), chloramphenicol (13%) and gentamicin (8%). A significantly lower prevalence of antibiotic resistance was found in Aeromonas from environmental control water, patient stool samples, duckweed and fish compared to sewage water isolates. The prevalence of resistance in the sewage water was not significantly reduced compared to the lagoon water and fish pond. Throughout the treatment system, the frequencies of resistant strains were found to diminish during the sewage water purification process, i.e. in the lagoon where sewage water is used to grow the duckweed. However, the frequency of resistant strains again increased in the fish pond where sewage grown duckweed is used for aquaculture. Among the selected isolates, two multiresistant clonal groups of Aeromonas caviae HG4 were identified that exhibited indistinguishable PhP and amplified fragment length polymorphism fingerprints and shared a common plasmid of approximately 5 kb

  9. Comparison of the prevalence of bacterial enteropathogens, potentially zoonotic bacteria and bacterial resistance to antimicrobials in organic and conventional poultry, swine and beef production: a systematic review and meta-analysis.

    PubMed

    Young, I; Rajić, A; Wilhelm, B J; Waddell, L; Parker, S; McEwen, S A

    2009-09-01

    The prevalences of zoonotic and potentially zoonotic bacteria or bacteria resistant to antimicrobials in organic and conventional poultry, swine and beef production were compared using systematic review and meta-analysis methodology. Thirty-eight articles were included in the review. The prevalence of Campylobacter was higher in organic broiler chickens at slaughter, but no difference in prevalence was observed in retail chicken. Campylobacter isolates from conventional retail chicken were more likely to be ciprofloxacin-resistant (odds ratio 9.62, 95% confidence interval 5.67-16.35). Bacteria isolated from conventional animal production exhibited a higher prevalence of resistance to antimicrobials; however, the recovery of some resistant strains was also identified in organic animal production, where there is an apparent reduced antimicrobial selection pressure. Limited or inconsistent research was identified in studies examining the prevalence of zoonotic and potentially zoonotic bacteria in other food-animal species. There is a need for further research of sufficient quality in this area. PMID:19379542

  10. Prevalence, characterization, and antimicrobial resistance of Yersinia species and Yersinia enterocolitica isolated from raw milk in farm bulk tanks.

    PubMed

    Jamali, Hossein; Paydar, Mohammadjavad; Radmehr, Behrad; Ismail, Salmah

    2015-02-01

    The aims of this study were to investigate the prevalence and to characterize and determine the antibiotic resistance of Yersinia spp. isolates from raw milk. From September 2008 to August 2010, 446 raw milk samples were obtained from farm bulk milk tanks in Varamin, Iran. Yersinia spp. were detected in 29 (6.5%) samples, out of which 23 (79.3%), 5 (17.2%), and 1 (3.4%) were isolated from cow, sheep, and goat raw milk, respectively. The most common species isolated was Yersinia enterocolitica (65.5%), followed by Yersinia frederiksenii (31%), and Yersinia kristensenii (3.4%). Of the 19 Y. enterocolitica isolates, 14 (73.7%) were grouped into bioserotype 1A/O:9, 4 (21.1%) belonged to bioserotype 1B:O8, 1 (5.3%) belonged to bioserotype 4/O:3, and 1 isolate (biotype 1A) was not typable. All the isolates of biotypes 1B and 4harbored both the ystA and ail genes. However, all the isolates of biotype 1A were only positive for the ystB gene. The tested Yersinia spp. showed the highest percentages of resistance to tetracycline (48.3%), followed by ciprofloxacin and cephalothin (each 17.2%), ampicillin (13.8%), streptomycin (6.9%), and amoxicillin and nalidixic acid (each 3.4%). All of the tested isolates demonstrated significant sensitivity to gentamicin and chloramphenicol. Recovery of potentially pathogenic Y. enterocolitica from raw milk indicates high risks of yersiniosis associated with consumption of raw milk.

  11. Antimicrobial Resistance Mechanisms among Campylobacter

    PubMed Central

    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

  12. Antimicrobial resistance: a global response.

    PubMed Central

    Smith, Richard D.; Coast, Joanna

    2002-01-01

    Resistance to antimicrobial therapies reduces the effectiveness of these drugs, leading to increased morbidity, mortality, and health care expenditure. Because globalization increases the vulnerability of any country to diseases occurring in other countries, resistance presents a major threat to global public health, and no country acting on its own can adequately protect the health of its population against it. International collective action is therefore essential. Nevertheless, responsibility for health remains predominantly national. Consequently, there is a potentially significant disparity between the problems and solutions related to antimicrobial resistance and the institutions and mechanisms that are available to deal with them. This paper considers the capacity of national and international institutions and mechanisms to generate a collective response to antimicrobial resistance. Strategies for containing resistance are outlined, with particular reference to globally coordinated activities of countries. The adequacy of national and international responses to resistance is assessed, and the actions that international bodies could take to solve difficulties associated with present responses are highlighted. Approaches are suggested for securing international collective action for the containment of antimicrobial resistance. PMID:11953791

  13. Antimicrobial use and antimicrobial resistance in nosocomial pathogens at a tertiary care hospital in Pune

    PubMed Central

    Nair, Velu; Sharma, Dinesh; Sahni, A.K.; Grover, Naveen; Shankar, S.; Jaiswal, S.S.; Dalal, S.S.; Basannar, D.R.; Phutane, Vivek S.; Kotwal, Atul; Gopal Rao, G.; Batura, Deepak; Venkatesh, M.D.; Sinha, Tapan; Kumar, Sushil; Joshi, D.P.

    2015-01-01

    Background Resistance to antimicrobial agents is emerging in wide variety of nosocomial and community acquired pathogens. Widespread and often inappropriate use of broad spectrum antimicrobial agents is recognized as a significant contributing factor to the development and spread of bacterial resistance. This study was conducted to gain insight into the prevalent antimicrobial prescribing practices, and antimicrobial resistance pattern in nosocomial pathogens at a tertiary care hospital in Pune, India. Methods Series of one day cross sectional point prevalence surveys were carried out on four days between March and August 2014. All eligible in patients were included in the study. A structured data entry form was used to collect the data for each patient. Relevant samples were collected for microbiological examination from all the clinically identified hospital acquired infection cases. Results 41.73% of the eligible patients (95% CI: 39.52–43.97) had been prescribed at least one antimicrobial during their stay in the hospital. Beta-lactams (38%) were the most prescribed antimicrobials, followed by Protein synthesis inhibitors (24%). Majority of the organisms isolated from Hospital acquired infection (HAI cases) were found to be resistant to the commonly used antimicrobials viz: Cefotaxime, Ceftriaxone, Amikacin, Gentamicin and Monobactams. Conclusion There is need to have regular antimicrobial susceptibility surveillance and dissemination of this information to the clinicians. In addition, emphasis on the rational use of antimicrobials, antimicrobial rotation and strict adherence to the standard treatment guidelines is very essential. PMID:25859071

  14. Antimicrobial resistance in Libya: 1970-2011.

    PubMed

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

    2013-01-01

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

  15. Prevalence and Trends of Staphylococcus aureus Bacteraemia in Hospitalized Patients in South Africa, 2010 to 2012: Laboratory-Based Surveillance Mapping of Antimicrobial Resistance and Molecular Epidemiology

    PubMed Central

    Perovic, Olga; Iyaloo, Samantha; Kularatne, Ranmini; Lowman, Warren; Bosman, Noma; Wadula, Jeannette; Seetharam, Sharona; Duse, Adriano; Mbelle, Nontombi; Bamford, Colleen; Dawood, Halima; Mahabeer, Yesholata; Bhola, Prathna; Abrahams, Shareef; Singh-Moodley, Ashika

    2015-01-01

    Introduction We aimed to obtain an in-depth understanding on recent antimicrobial resistance trends and molecular epidemiology trends of S. aureus bacteraemia (SAB). Methods Thirteen academic centres in South Africa were included from June 2010 until July 2012. S. aureus susceptibility testing was performed on the MicroScan Walkaway. Real-time PCR using the LightCycler 480 II was done for mecA and nuc. SCCmec and spa-typing were finalized with conventional PCR. We selected one isolate per common spa type per province for multilocus sequence typing (MLST). Results S. aureus from 2709 patients were included, and 1231 (46%) were resistant to methicillin, with a significant decline over the three-year period (p-value = 0.003). Geographical distribution of MRSA was significantly higher in Gauteng compared to the other provinces (P<0.001). Children <5 years were significantly associated with MRSA with higher rates compared to all other age groups (P = 0.01). The most prevalent SCCmec type was SCCmec type III (531 [41%]) followed by type IV (402 [31%]). Spa-typing discovered 47 different spa-types. The five (87%) most common spa-types were t037, t1257, t045, t064 and t012. Based on MLST, the commonest was ST612 clonal complex (CC8) (n = 7) followed by ST5 (CC5) (n = 4), ST36 (CC30) (n = 4) and ST239 (CC8) (n = 3). Conclusions MRSA rate is high in South Africa. Majority of the isolates were classified as SCCmec type III (41%) and type IV (31%), which are typically associated with hospital and community- acquired infections, respectively. Overall, this study reveals the presence of a variety of hospital-acquired MRSA clones in South Africa dominance of few clones, spa 037 and 1257. Monitoring trends in resistance and molecular typing is recommended to detect changing epidemiological trends in AMR patterns of SAB. PMID:26719975

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    PubMed

    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 < 0.05) in municipal samples than in cattle runoff or swine lagoon samples. In conclusion, we report that AMR is a very widespread phenomenon and that similar prevalences

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

    PubMed

    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 < 0.05) in municipal samples than in cattle runoff or swine lagoon samples. In conclusion, we report that AMR is a very widespread phenomenon and that similar prevalences

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

    PubMed Central

    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 < 0.05) in municipal samples than in cattle runoff or swine lagoon samples. In conclusion, we report that AMR is a very widespread phenomenon and that similar

  20. Impact of Antimicrobial Usage on Antimicrobial Resistance in Commensal Escherichia coli Strains Colonizing Broiler Chickens▿

    PubMed Central

    Smith, J. L.; Drum, D. J. V.; Dai, Y.; Kim, J. M.; Sanchez, S.; Maurer, J. J.; Hofacre, C. L.; Lee, M. D.

    2007-01-01

    Escherichia coli strains isolated from commercial broilers and an experimental flock of chickens were screened to determine phenotypic expression of antimicrobial resistance and carriage of drug resistance determinants. The goal of this study was to investigate the influence of oxytetracycline, sarafloxacin, and enrofloxacin administration on the distribution of resistance determinants and strain types among intestinal commensal E. coli strains isolated from broiler chickens. We detected a high prevalence of resistance to drugs such as tetracycline (36 to 97%), sulfonamides (50 to 100%), and streptomycin (53 to 100%) in E. coli isolates from treated and untreated flocks. These isolates also had a high prevalence of class 1 integron carriage, and most of them possessed the streptomycin resistance cassette, aadA1. In order to investigate the contribution of E. coli strain distribution to the prevalence of antimicrobial resistance and the resistance determinants, isolates from each flock were DNA fingerprinted by enterobacterial repetitive intergenic consensus sequence (ERIC) PCR. Although very diverse E. coli strain types were detected, four ERIC strain types were present on all of the commercial broiler farms, and two of the strains were also found in the experimental flocks. Each E. coli strain consisted of both susceptible and antimicrobial agent-resistant isolates. In some instances, isolates of the same E. coli strain expressed the same drug resistance patterns although they harbored different tet determinants or streptomycin resistance genes. Therefore, drug resistance patterns could not be explained solely by strain prevalence, indicating that mobile elements contributed significantly to the prevalence of resistance. PMID:17194843

  1. Prevalence of antimicrobial resistance in Salmonella serotype Hadar isolated from humans, retail meat, and food animals at slaughter, United States, NARMS 1996-2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background Non-Typhi Salmonella (NTS) is a leading cause of bacterial gastroenteritis in the United States. Although most infections are self-limited, antibiotic treatment is essential for severe illness. Use of antimicrobial agents in food animals contributes to resistance in NTS. Multidrug resis...

  2. Antimicrobial resistance in Saudi Arabia

    PubMed Central

    Zowawi, Hosam M.

    2016-01-01

    Antimicrobial resistance (AMR) is increasingly being highlighted as an urgent public and animal health issue worldwide. This issue is well demonstrated in bacteria that are resistant to last-line antibiotics, suggesting a future with untreatable infections. International agencies have suggested combating strategies against AMR. Saudi Arabia has several challenges that can stimulate the emergence and spread of multidrug-resistant bacteria. Tackling these challenges need efforts from multiple sectors to successfully control the spread and emergence of AMR in the country. Actions should include active surveillance to monitor the emergence and spread of AMR. Infection prevention and control precautions should also be optimized to limit further spread. Raising awareness is essential to limit inappropriate antibiotics use, and the antibiotic stewardship programs in hospital settings, outpatients, and community pharmacies, should regulate the ongoing use of antimicrobials. PMID:27570847

  3. Antimicrobial resistance of mastitis pathogens.

    PubMed

    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

  4. Antimicrobial (Drug) Resistance Prevention

    MedlinePlus

    ... Action Plan for Combating Antibiotic-Resistant Bacteria (PDF) ​​​​​​ Javascript Error Your browser JavaScript is turned off causing certain features of the ... incorrectly. Please visit your browser settings and turn JavaScript on. Read more information on enabling JavaScript. Skip ...

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

    PubMed Central

    Guruge, Keerthi S.; Yamanaka, Noriko; Sonobe, Miyuki; Fujizono, Wataru; Yoshioka, Miyako; Akiba, Masato; Yamamoto, Takehisa; Joshua, Derrick I.; Balakrishna, Keshava; Yamashita, Nobuyoshi; Kannan, Kurunthachalam; Tsutsui, Toshiyuki

    2015-01-01

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

  6. Antimicrobial Resistance in the Environment.

    PubMed

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

    2016-10-01

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

  7. The Relationship between Antimicrobial Use and Antimicrobial Resistance in Europe

    PubMed Central

    Cars, Otto; Buchholz, Udo; Mölstad, Sigvard; Goettsch, Wim; Veldhuijzen, Irene K.; Kool, Jacob L.; Sprenger, Marc J.W.; Degener, John E.

    2002-01-01

    In Europe, antimicrobial resistance has been monitored since 1998 by the European Antimicrobial Resistance Surveillance System (EARSS). We examined the relationship between penicillin nonsusceptibility of invasive isolates of Streptococcus pneumoniae (an indicator organism) and antibiotic sales. Information was collected on 1998-99 resistance data for invasive isolates of S. pneumoniae to penicillin, based on surveillance data from EARSS and on outpatient sales during 1997 for beta-lactam antibiotics and macrolides. Our results show that in Europe antimicrobial resistance is correlated with use of beta-lactam antibiotics and macrolides. PMID:11927025

  8. Can we prevent antimicrobial resistance by using antimicrobials better?

    PubMed

    Soothill, Germander; Hu, Yanmin; Coates, Anthony

    2013-06-10

    Since their development over 60 years ago, antimicrobials have become an integral part of healthcare practice worldwide. Recently, this has been put in jeopardy by the emergence of widespread antimicrobial resistance, which is one of the major problems facing modern medicine. In the past, the development of new antimicrobials kept us one step ahead of the problem of resistance, but only three new classes of antimicrobials have reached the market in the last thirty years. A time is therefore approaching when we may not have effective treatment against bacterial infections, particularly for those that are caused by Gram-negative organisms. An important strategy to reduce the development of antimicrobial resistance is to use antimicrobials more appropriately, in ways that will prevent resistance. This involves a consideration of the pharmacokinetic and pharmacodynamics properties of antimicrobials, the possible use of combinations, and more appropriate choice of antimicrobials, which may include rapid diagnostic testing and antimicrobial cycling. Examples given in this review include Mycobacterium tuberculosis, Gram-negative and Gram-positive organisms. We shall summarise the current evidence for these strategies and outline areas for future development.

  9. Mechanisms of antimicrobial resistance in finfish aquaculture environments.

    PubMed

    Miranda, Claudio D; Tello, Alfredo; Keen, Patricia L

    2013-01-01

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

  10. Antimicrobial Resistance: Is the World UNprepared?

    PubMed

    2016-09-01

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

  11. Correlations between Income Inequality and Antimicrobial Resistance

    PubMed Central

    Kirby, Andrew; Herbert, Annie

    2013-01-01

    Objectives 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. Data collection and analysis 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. Results 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). Conclusion As income inequality increases in European countries so do the rates of antimicrobial resistance for bacteria including E. faecalis, E. coli, K. pneumoniae

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  13. Antimicrobial Resistance in Haemophilus influenzae

    PubMed Central

    Tristram, Stephen; Jacobs, Michael R.; Appelbaum, Peter C.

    2007-01-01

    Haemophilus influenzae is a major community-acquired pathogen causing significant morbidity and mortality worldwide. Meningitis and bacteremia due to type b strains occur in areas where the protein-conjugated type b vaccine is not in use, whereas nontypeable strains are major causes of otitis media, sinusitis, acute exacerbations of chronic bronchitis, and pneumonia. Antibiotic resistance in this organism is more diverse and widespread than is commonly appreciated. Intrinsic efflux resistance mechanisms limit the activity of the macrolides, azalides, and ketolides. β-Lactamase production is highly prevalent worldwide and is associated with resistance to ampicillin and amoxicillin. Strains with alterations in penicillin binding proteins, particularly PBP3 (β-lactamase negative ampicillin resistant and β-lactamase positive amoxicillin-clavulanate resistant), are increasing in prevalence, particularly in Japan, with increasing resistance to ampicillin, amoxicillin, amoxicillin-clavulanate, and many cephalosporins, limiting the efficacy of expanded-spectrum cephalosporins against meningitis and of many oral cephalosporins against other diseases. Most strains remain susceptible to the carbapenems, which are not affected by penicillin binding protein changes, and the quinolones. The activity of many oral agents is limited by pharmacokinetics achieved with administration by this route, and the susceptibility of isolates based on pharmacokinetic and pharmacodynamic parameters is reviewed. PMID:17428889

  14. The challenges of antimicrobial resistance in Brazil.

    PubMed

    Rossi, Flávia

    2011-05-01

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

  15. Antimicrobial (Drug) Resistance: Vancomycin-Resistant Enterococci (VRE) Frequently Asked Questions

    MedlinePlus

    ... Understanding Antimicrobial (Drug) Resistance Examples of Antimicrobial Resistance Methicillin-Resistant Staphylococcus aureus (MRSA) Vancomycin-Resistant Enterococci (VRE) Overview Transmission Diagnosis ...

  16. Legal issues associated with antimicrobial drug resistance.

    PubMed Central

    Fidler, D. P.

    1998-01-01

    An effective public health strategy against the development of antimicrobial drug resistance needs to be informed by legal as well as scientific analysis. This article describes some legal issues arising from current efforts against antimicrobial resistance and underscores the interdependence between law and public health in these efforts. PMID:9621187

  17. Antimicrobial resistance issues in beef production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  18. Combating Antimicrobial Resistance in Foodborne Microorganisms.

    PubMed

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

    2016-02-01

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

  19. Epidemiology of antimicrobial resistance in bloodstream infections.

    PubMed

    Akova, Murat

    2016-04-01

    Antimicrobial resistance in bacterial pathogens is a worldwide challenge leading high morbidity and mortality in clinical settings. Multidrug resistant patterns in gram-positive and -negative bacteria have resulted in difficult-to-treat or even untreatable infections with conventional antimicrobials. Since the early identification of causative microorganisms and their antimicrobial susceptibility patterns in patients with bacteremia and other serious infections is lacking in many healthcare institutions, broad spectrum antibiotics are liberally and mostly unnecessarily used. Such practice has, in turn, caused dramatic increases in emerging resistance and when coupled with poor practice of infection control, resistant bacteria can easily be disseminated to the other patients and the environment. Thus, availability of updated epidemiological data on antimicrobial resistance in frequently encountered bacterial pathogens will be useful not only for deciding on empirical treatment strategies, but also devising an effective antimicrobial stewardship program in hospitals. PMID:26984779

  20. Prevalence and antimicrobial susceptibility of Salmonella infections in free-range pigs.

    PubMed

    Gómez-Laguna, Jaime; Hernández, Manuela; Creus, Eva; Echeita, Aurora; Otal, Julio; Herrera-León, Silvia; Astorga, Rafael J

    2011-10-01

    The prevalence of Salmonella spp. infection was determined in 67 free-range pig herds in southern Spain. Microbiological assessment was performed on ileocolic lymph nodes collected at slaughter according to ISO 6579:2002 procedures. Overall, 33% of herds were infected and the prevalence of infection was 5.3%. Salmonella spp. serovars most frequently isolated were Anatum and Typhimurium, although uncommon serovars such as Hessarek and Mikawasima were also detected. Isolates were tested against 16 antimicrobial agents and exhibited resistance to streptomycin (46%), tetracycline (30%), sulphonamides (25%) and ampicillin (23%) by the break-point method. Multi-drug resistance, defined as resistance to ≥ 4 antimicrobials, was 36%.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

    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.

  3. Mechanisms of Antimicrobial Resistance in ESKAPE Pathogens

    PubMed Central

    Santajit, Sirijan; Indrawattana, Nitaya

    2016-01-01

    The ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) are the leading cause of nosocomial infections throughout the world. Most of them are multidrug resistant isolates, which is one of the greatest challenges in clinical practice. Multidrug resistance is amongst the top three threats to global public health and is usually caused by excessive drug usage or prescription, inappropriate use of antimicrobials, and substandard pharmaceuticals. Understanding the resistance mechanisms of these bacteria is crucial for the development of novel antimicrobial agents or other alternative tools to combat these public health challenges. Greater mechanistic understanding would also aid in the prediction of underlying or even unknown mechanisms of resistance, which could be applied to other emerging multidrug resistant pathogens. In this review, we summarize the known antimicrobial resistance mechanisms of ESKAPE pathogens. PMID:27274985

  4. Antimicrobial resistance and virulence of Enterococcus faecalis isolated from retail food

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although enterococci are considered opportunistic nosocomial pathogens, their contribution to food-borne illnesses via dissemination through retail food remains undefined. In this study, prevalence and association of antimicrobial resistance and virulence factors of 80 Enterococcus faecalis isolate...

  5. Presence of antimicrobial resistance and antimicrobial use in sows are risk factors for antimicrobial resistance in their offspring.

    PubMed

    Callens, Bénédicte; Faes, Christel; Maes, Dominiek; Catry, Boudewijn; Boyen, Filip; Francoys, Delphine; de Jong, Ellen; Haesebrouck, Freddy; Dewulf, Jeroen

    2015-02-01

    This study investigated whether antimicrobial-resistant Escherichia coli in apparently healthy sows and antimicrobial administration to sows and piglets influenced antimicrobial resistance in fecal commensal E. coli from piglets. Sixty sows from three herds and three of their piglets were sampled at several time points. Antimicrobial usage data during parturition and farrowing were collected. Clinical resistance was determined for two isolates per sampling time point for sows and piglets using disk diffusion. Only 27.4% of E. coli isolates from newborn piglets showed no resistance. Resistance to one or two antimicrobial classes equaled 41.2% and 46.8% in isolates from sows and piglets, respectively, for the overall farrowing period. Multiresistance to at least four classes was found as frequently in sows (15.6%) as in piglets (15.2%). Antimicrobial resistance in piglets was influenced by antimicrobial use in sows and piglets and by the sow resistance level (p≤0.05). Using aminopenicillins and third-generation cephalosporins in piglets affected resistance levels in piglets (odds ratios [OR] >1; p≤0.05). Using enrofloxacin in piglets increased the odds for enrofloxacin resistance in piglets (OR=26.78; p≤0.0001) and sows at weaning (OR=4.04; p≤0.05). For sows, antimicrobial exposure to lincomycin-spectinomycin around parturition increased the resistance to ampicillin, streptomycin, trimethoprim-sulfadiazine in sows (OR=21.33, OR=142.74, OR=18.03; p≤0.05) and additionally to enrofloxacin in piglets (OR=7.50; p≤0.05). This study demonstrates that antimicrobial use in sows and piglets is a risk factor for antimicrobial resistance in the respective animals. Moreover, resistance determinants in E. coli from piglets are selected by using antimicrobials in their dam around parturition.

  6. Prevalence and Antimicrobial Susceptibility of Campylobacter spp. in Oklahoma Conventional and Organic Retail Poultry

    PubMed Central

    Noormohamed, Aneesa; Fakhr, Mohamed K

    2014-01-01

    Campylobacter is one of the most important foodborne pathogens that cause bacterial gastroenteritis.This study was conducted to investigate the prevalence and antimicrobial resistance of Campylobacter in conventional and organic retail poultry samples purchased from grocery stores in Tulsa, Oklahoma.One hundred and fifty six chilled retail chicken samples (85 conventional and 71 organic) and 65 chilled retail conventional turkey samples were collected in this study. The prevalence of Campylobacter in the conventional chicken samples 32/85 (38%) was higher than in the organic ones 21/71 (30%). The prevalence of Campylobacter in the conventional turkey samples was 11/65 (17%). Of the 53 positive chicken samples, 42 were C. jejuni, 8 were C. coli and three isolates were contaminated with both species. Of the 11 positive turkey samples, 8 contained C. jejuni and 3 harbored C. coli isolates. The antimicrobial susceptibility of one hundred and forty nine recovered Campylobacter isolates (130 chickens and 19 turkeys) towards sixteen antimicrobials was determined. The majority of the recovered turkey isolates (13/19) showed resistance to more than 7 antimicrobials while most of the recovered chicken ones (82/130) were resistant to 5 to 7 antimicrobials. Multidrug resistance was not limited to isolates from conventional sources but was also available in isolates of an organic background and was generally lower in C. jejuni isolates when compared to the C. coli ones. PMID:25408778

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

    PubMed

    Wallmann, Jürgen

    2006-06-01

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

  8. Prevalence, quantification and antimicrobial resistance of Campylobacter spp. on chicken neck-skins at points of slaughter in 5 major cities located on 4 continents.

    PubMed

    Garin, Benoit; Gouali, Malika; Wouafo, Marguerite; Perchec, Anne-Marie; Pham, Minh Thu; Ravaonindrina, Noro; Urbès, Florence; Gay, Manu; Diawara, Abdoulaye; Leclercq, Alexandre; Rocourt, Jocelyne; Pouillot, Régis

    2012-06-15

    Quantitative data on Campylobacter contamination of food are lacking, notably in developing countries. We assessed Campylobacter contamination of chicken neck-skins at points of slaughter in 5 major cities in Africa (Dakar in Senegal, Yaounde in Cameroon), Oceania (Noumea in New Caledonia), the Indian Ocean (Antananarivo in Madagascar) and Asia (Ho Chi Minh City (HCMC) in Vietnam. One hundred and fifty slaughtered chickens were collected in each of the 5 major cities from semi-industrial abattoirs or markets (direct slaughter by the seller), and 65.5% (491/750) were found to be Campylobacter-positive. Two cities, Yaounde and Noumea, demonstrated high prevalence Campylobacter detection rates (92.7% and 96.7% respectively) in contrast with HCMC (15.3%). Four species were identified among 633 isolates, namely C. jejuni (48.3%), C. coli (37.3%), C. lari (11.7%) and C. upsaliensis (1%). HCMC was the only city with C. lari isolation as was Antananarivo for C. upsaliensis. C. coli was highly prevalent only in Yaounde (69.5%). Among the 491 samples positive in Campylobacter detection, 329 were also positive with the enumeration method. The number of Campylobacter colony-forming units (CFU) per gram of neck-skin in samples positive in enumeration was high (mean of the log(10): 3.2 log(10) CFU/g, arithmetic mean: 7900CFU/g). All the cities showed close enumeration means except HCMC with a 1.81 log(10) CFU/g mean for positive samples. Semi-industrial abattoir was linked to a significant lower count of Campylobacter contamination than direct slaughter by the seller (p=0.006). On 546 isolates (546/633, 86.3%) tested for antibiotic susceptibility, resistance to erythromycin, ampicillin and ciprofloxacin was observed for respectively 11%, 19% and 50%. HCMC was the city where antibiotic resistant rates were the highest (95%, p=0.014). Considering the 329 positive chickens in Campylobacter enumeration, the mean number of resistant isolates to at least 2 different antibiotic

  9. Prevalence, quantification and antimicrobial resistance of Campylobacter spp. on chicken neck-skins at points of slaughter in 5 major cities located on 4 continents.

    PubMed

    Garin, Benoit; Gouali, Malika; Wouafo, Marguerite; Perchec, Anne-Marie; Pham, Minh Thu; Ravaonindrina, Noro; Urbès, Florence; Gay, Manu; Diawara, Abdoulaye; Leclercq, Alexandre; Rocourt, Jocelyne; Pouillot, Régis

    2012-06-15

    Quantitative data on Campylobacter contamination of food are lacking, notably in developing countries. We assessed Campylobacter contamination of chicken neck-skins at points of slaughter in 5 major cities in Africa (Dakar in Senegal, Yaounde in Cameroon), Oceania (Noumea in New Caledonia), the Indian Ocean (Antananarivo in Madagascar) and Asia (Ho Chi Minh City (HCMC) in Vietnam. One hundred and fifty slaughtered chickens were collected in each of the 5 major cities from semi-industrial abattoirs or markets (direct slaughter by the seller), and 65.5% (491/750) were found to be Campylobacter-positive. Two cities, Yaounde and Noumea, demonstrated high prevalence Campylobacter detection rates (92.7% and 96.7% respectively) in contrast with HCMC (15.3%). Four species were identified among 633 isolates, namely C. jejuni (48.3%), C. coli (37.3%), C. lari (11.7%) and C. upsaliensis (1%). HCMC was the only city with C. lari isolation as was Antananarivo for C. upsaliensis. C. coli was highly prevalent only in Yaounde (69.5%). Among the 491 samples positive in Campylobacter detection, 329 were also positive with the enumeration method. The number of Campylobacter colony-forming units (CFU) per gram of neck-skin in samples positive in enumeration was high (mean of the log(10): 3.2 log(10) CFU/g, arithmetic mean: 7900CFU/g). All the cities showed close enumeration means except HCMC with a 1.81 log(10) CFU/g mean for positive samples. Semi-industrial abattoir was linked to a significant lower count of Campylobacter contamination than direct slaughter by the seller (p=0.006). On 546 isolates (546/633, 86.3%) tested for antibiotic susceptibility, resistance to erythromycin, ampicillin and ciprofloxacin was observed for respectively 11%, 19% and 50%. HCMC was the city where antibiotic resistant rates were the highest (95%, p=0.014). Considering the 329 positive chickens in Campylobacter enumeration, the mean number of resistant isolates to at least 2 different antibiotic

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

    PubMed Central

    Radhouani, Hajer; Silva, Nuno; Poeta, Patrícia; Torres, Carmen; Correia, Susana; Igrejas, Gilberto

    2014-01-01

    Given the significant spatial and temporal heterogeneity in antimicrobial resistance distribution and the factors that affect its evolution, dissemination, and persistence, it is important to highlight that antimicrobial resistance must be viewed as an ecological problem. Monitoring the resistance prevalence of indicator bacteria such as Escherichia coli and enterococci in wild animals makes it possible to show that wildlife has the potential to serve as an environmental reservoir and melting pot of bacterial resistance. These researchers address the issue of antimicrobial-resistant microorganism proliferation in the environment and the related potential human health and environmental impact. PMID:24550896

  11. Danish Integrated Antimicrobial Resistance Monitoring and Research Program

    PubMed Central

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

    2007-01-01

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

  12. Health and economic impacts of antimicrobial resistance.

    PubMed

    Holmberg, S D; Solomon, S L; Blake, P A

    1987-01-01

    For comparison of the impacts of infections due to antimicrobial-resistant bacteria with those of infections due to antimicrobial-susceptible strains of the same bacteria, data were evaluated from 175 published and unpublished reports of investigations of nosocomial and community-acquired infections with selected bacteria. The evaluation of outcomes of hospital-acquired infections with resistant organisms was often confounded by risk factors also associated with poor outcomes. Nevertheless, for both nosocomial and community-acquired infections, the mortality, the likelihood of hospitalization, and the length of hospital stay were usually at least twice as great for patients infected with drug-resistant strains as for those infected with drug-susceptible strains of the same bacteria. Poor outcomes could be attributed both to the expected effects of ineffective antimicrobial therapy and to the unexpected occurrence of drug-resistant infections complicated by prior antimicrobial therapy for other medical problems. Although the adverse economic and health effects of drug-resistant bacterial infections can only be roughly quantified, it is concluded that antimicrobial resistance is an important health problem and an economic burden to society. PMID:3321356

  13. Antimicrobial Resistance in Escherichia coli Recovered from Feedlot Cattle and Associations with Antimicrobial Use

    PubMed Central

    Benedict, Katharine M.; Gow, Sheryl P.; McAllister, Tim A.; Booker, Calvin W.; Hannon, Sherry J.; Checkley, Sylvia L.; Noyes, Noelle R.; Morley, Paul S.

    2015-01-01

    The objectives of this study were to estimate the prevalence of antimicrobial resistance (AMR) and to investigate the associations between exposures to antimicrobial drugs (AMDs) and AMR in fecal non-type specific Escherichia coli (NTSEC) recovered from a large population of feedlot cattle. Two-stage random sampling was used to select individually identified cattle for enrollment, which were sampled at arrival and then a second time later in the feeding period. Advanced regression techniques were used to estimate resistance prevalences, and to investigate associations between AMD exposures in enrolled cattle and penmates and AMR identified in NTSEC recovered from the second sample set. Resistance was most commonly detected to tetracycline, streptomycin, and sulfisoxazole, and was rarely identified for critically important AMDs. All cattle were exposed to AMDs in feed, and 45% were treated parenterally. While resistance prevalence generally increased during the feeding period, most AMD exposures were not significantly associated with AMR outcomes. Exposures of enrolled cattle to tetracycline were associated with increased resistance to tetracycline and trimethoprim sulfa, while beta-lactam exposures were associated with decreased likelihood of detecting streptomycin resistance. Pen-level AMD exposure measures were not associated with resistance outcomes. These findings suggest that tetracycline treatment of feedlot cattle can be associated with modest increases in risk for recovery of resistant NTSEC, but the numerous treatments with an advanced macrolide (tulathromycin) were not associated with detectable increases in resistance in NTSEC. All cattle were exposed to in-feed treatments of tetracycline and this could limit the ability to identify the full impact of these exposures, but these exposures varied for enrolled cattle varied, providing an opportunity to evaluate a dose response. While AMD exposures were not associated with detectably increased risks for

  14. Prevalence and risk factors of early fecal carriage of Enterococcus faecalis and Staphylococcus spp and their antimicrobial resistant patterns among healthy neonates born in a hospital setting in central Saudi Arabia

    PubMed Central

    El-Kersh, Talat A.; Marie, Mohammed A.; Al-Sheikh, Yazeed A.; Al-Agamy, Mohamed H.; Al-Bloushy, Ahmad A.

    2016-01-01

    Objectives: To investigate the prevalence, antibiotic resistant profiles, and risk factors of early fecal carriage of Enterococcus faecalis (E. faecalis) and staphylococci among 150 healthy Saudi neonates born in a hospital setting in central Saudi Arabia. Methods: This prospective study was conducted in Al-Bukayriyah General Hospital, Qassim, Saudi Arabia, between June 2012 and January 2013. The E. faecalis and Staphylococcus spp. isolates were identified manually, and Vitek2 system was used for identity confirmation at the species level and minimum inhibitory concentration-susceptibility testing. Results: Enterococcus faecalis (n=73) and Staphylococcus spp. (n=18) were recovered. Unlike staphylococci, E. faecalis colonization did not significantly vary from day one up to 7 days of life, regardless of the type of feeding, but it was relatively higher among vaginally versus cesarean delivery. Both Staphylococcus epidermidis (S. epidermidis) and Staphylococcus aureus carriage increase as the body weight increases, and this difference was significant (p=0.025) for S. epidermidis. High-level resistance in Gentamycin among E. faecalis isolates was 25% and 11% to Streptomycin. Thirty percent of S. epidermidis were resistant to oxacillin and exhibited multidrug-resistant (MDR) patterns of 5 resistant markers, which were also observed among 2/5 (40%) of Methicillin-resistant Staphylococcus aureus isolates. Conclusion: Enterococcus faecalis did not significantly vary in relation to type of delivery, age up to 7 days, and type of feeding. The neonatal fecal carriage of MDR isolates should be considered as a crucial reservoir to the further spread of antimicrobial resistance genes among hospitals, cross infections, and the community. PMID:26905350

  15. Bacterial resistance and topical antimicrobial wash products.

    PubMed

    Jones, R D

    1999-08-01

    Current scientific evidence has not shown that a link exists between the use of topical antimicrobial formulations and antiseptic or antibiotic resistance. As a result of the extensive history and varied use of antiseptic products and ingredients, any selective pressure for antibiotic resistance that may be occurring or may be uncovered in the future because of antiseptic use would be expected to be insignificant compared with the selective pressure because of antibiotic use. This review illustrates the effectiveness of topical antimicrobial wash products against antibiotic-resistant and antiseptic-resistant bacteria in use settings as well as the studies performed (antiseptic, deodorant, and oral care) demonstrating the lack of development of resistance in long-term clinical studies. Although these studies illustrate that the use of topical antimicrobial products have not been shown to play a role in the fluctuations of the specific composition or resistance of the skin flora, changes in skin flora have been shown to occur. Based on current knowledge, the benefit from use of topical antimicrobial wash products in combination with standard infection control and personal hygiene practices far outweighs the risk of increased antibiotic resistance.

  16. Role of calf-adapted Escherichia coli in maintenance of antimicrobial drug resistance in dairy calves.

    PubMed

    Khachatryan, Artashes R; Hancock, Dale D; Besser, Thomas E; Call, Douglas R

    2004-02-01

    The prevalence of antimicrobial drug-resistant bacteria is typically highest in younger animals, and prevalence is not necessarily related to recent use of antimicrobial drugs. In dairy cattle, we hypothesize that antimicrobial drug-resistant, neonate-adapted bacteria are responsible for the observed high frequencies of resistant Escherichia coli in calves. To explore this issue, we examined the age distribution of antimicrobial drug-resistant E. coli from Holstein cattle at a local dairy and conducted an experiment to determine if low doses of oxytetracycline affected the prevalence of antimicrobial drug-resistant E. coli. Isolates resistant to tetracycline (>4 microg/ml) were more prevalent in <3-month-old calves (79%) compared with lactating cows (14%). In an experimental trial where calves received diets supplemented with or without oxytetracycline, the prevalence of tetracycline-resistant E. coli was slightly higher for the latter group (P = 0.039), indicating that drug use was not required to maintain a high prevalence of resistant E. coli. The most common resistance pattern among calf E. coli isolates included resistance to streptomycin (>12 microg/ml), sulfadiazine (>512 microg/ml), and tetracycline (>4 microg/ml) (SSuT), and this resistance pattern was most prevalent during the period when calves were on milk diets. To determine if prevalence was a function of differential fitness, we orally inoculated animals with nalidixic acid-resistant strains of SSuT E. coli and susceptible E. coli. Shedding of SSuT E. coli was significantly greater than that of susceptible strains in neonatal calves (P < 0.001), whereas there was no difference in older animals (P = 0.5). These data support the hypothesis that active selection for traits linked to the SSuT phenotype are responsible for maintaining drug-resistant E. coli in this population of dairy calves.

  17. Bacterial strategies of resistance to antimicrobial peptides.

    PubMed

    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'. PMID:27160595

  18. Bacterial strategies of resistance to antimicrobial peptides.

    PubMed

    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'.

  19. Understanding the mechanisms and drivers of antimicrobial resistance.

    PubMed

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

    2016-01-01

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

  20. Antimicrobial peptide resistance in Neisseria meningitidis.

    PubMed

    Tzeng, Yih-Ling; Stephens, David S

    2015-11-01

    Antimicrobial peptides (AMPs) play an important role as a host defense against microbial pathogens and are key components of the human innate immune response. Neisseria meningitidis frequently colonizes the human nasopharynx as a commensal but also is a worldwide cause of epidemic meningitis and rapidly fatal sepsis. In the human respiratory tract, the only known reservoir of N. meningitidis, meningococci are exposed to human endogenous AMPs. Thus, it is not surprising that meningococci have evolved effective mechanisms to confer intrinsic and high levels of resistance to the action of AMPs. This article reviews the current knowledge about AMP resistance mechanisms employed by N. meningitidis. Two major resistance mechanisms employed by meningococci are the constitutive modification of the lipid A head groups of lipooligosaccharides by phosphoethanolamine and the active efflux pump mediated excretion of AMPs. Other factors influencing AMP resistance, such as the major porin PorB, the pilin biogenesis apparatus, and capsular polysaccharides, have also been identified. Even with an inherently high intrinsic resistance, several AMP resistance determinants can be further induced upon exposure to AMPs. Many well-characterized AMP resistance mechanisms in other Gram-negative bacteria are not found in meningococci. Thus, N. meningitidis utilizes a limited but highly effective set of molecular mechanisms to mediate antimicrobial peptide resistance. This article is part of a Special Issue entitled: Bacterial Resistance to Antimicrobial Peptides.

  1. Resistance in antimicrobial photodynamic inactivation of bacteria.

    PubMed

    Maisch, Tim

    2015-08-01

    Antibiotics have increasingly lost their impact to kill bacteria efficiently during the last 10 years. The emergence and dissemination of superbugs with resistance to multiple antibiotic classes have occurred among Gram-positive and Gram-negative strains including Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter strains. These six superbugs can "escape" more or less any single kind of antibiotic treatment. That means bacteria are very good at developing resistance against antibiotics in a short time. One new approach is called photodynamic antimicrobial chemotherapy (PACT) which already has demonstrated an efficient antimicrobial efficacy among multi-resistant bacteria. Until now it has been questionable if bacteria can develop resistance against PACT. This perspective summarises the current knowledge about the susceptibility of bacteria towards oxidative stress and sheds some light on possible strategies of the development of photodynamic inactivation of bacteria (PACT)-induced oxidative stress resistance by bacteria.

  2. ACVIM consensus statement on therapeutic antimicrobial use in animals and antimicrobial resistance.

    PubMed

    Weese, J S; Giguère, S; Guardabassi, L; Morley, P S; Papich, M; Ricciuto, D R; Sykes, J E

    2015-01-01

    The epidemic of antimicrobial resistant infections continues to challenge, compromising animal care, complicating food animal production and posing zoonotic disease risks. While the overall role of therapeutic antimicrobial use in animals in the development AMR in animal and human pathogens is poorly defined, veterinarians must consider the impacts of antimicrobial use in animal and take steps to optimize antimicrobial use, so as to maximize the health benefits to animals while minimizing the likelihood of antimicrobial resistance and other adverse effects. This consensus statement aims to provide guidance on the therapeutic use of antimicrobials in animals, balancing the need for effective therapy with minimizing development of antimicrobial resistance in bacteria from animals and humans.

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

    PubMed

    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.

  4. Risk factors for antimicrobial resistance in fecal Escherichia coli from preweaned dairy calves.

    PubMed

    Duse, Anna; Waller, Karin Persson; Emanuelson, Ulf; Unnerstad, Helle Ericsson; Persson, Ylva; Bengtsson, Björn

    2015-01-01

    The primary objective of this study was to investigate calf and farm factors associated with antimicrobial-resistant Escherichia coli in the feces of preweaned dairy calves in Sweden. In particular, we investigated the effects of feeding calves colostrum and milk from cows treated with antimicrobials. The secondary objective was to describe the prevalence of resistant E. coli in feces of preweaned dairy calves in Sweden. Fecal samples from 3 calves, aged 7 to 28d, from 243 farms were analyzed for the within-sample prevalence of E. coli resistant to nalidixic acid, streptomycin, and cefotaxime using selective agars supplemented with antimicrobials. In addition, resistance to 12 antimicrobials was tested in one randomly selected E. coli isolate per calf. Information was collected from the farmers via questionnaires regarding the use of colostrum and milk from cows treated with antimicrobials as calf feed and other uses of antimicrobials in the herd. Multivariable zero-inflated negative binomial and logistic regression models were used to assess the effect of various risk factors for shedding of resistant E. coli. Escherichia coli resistant to streptomycin, nalidixic acid, or cefotaxime were isolated from 90, 49, and 11% of the calves, respectively. Resistance to at least one antimicrobial was found in a random isolate of E. coli from 48% of the calves. Feeding colostrum from cows treated with antimicrobials at drying off did not affect the prevalence of resistant E. coli. In contrast, feeding milk from cows treated with antimicrobials during lactation resulted in significantly more nalidixic acid- and streptomycin-resistant E. coli than when such milk was discarded; no significant effect was seen for other resistance traits. Furthermore, an interaction was found between feeding milk from cows treated with antimicrobials and use of fluoroquinolones in cows. In general, the prevalence of resistance was lower for older calves and calves on small farms. Other factors

  5. Antimicrobial resistance and management of invasive Salmonella disease

    PubMed Central

    Kariuki, Samuel; Gordon, Melita A.; Feasey, Nicholas; Parry, Christopher M

    2015-01-01

    Invasive Salmonella infections (typhoidal and non-typhoidal) cause a huge burden of illness estimated at nearly 3.4 million cases and over 600,000 deaths annually especially in resource-limited settings. Invasive non-typhoidal Salmonella (iNTS) infections are particularly important in immunosuppressed populations especially in sub-Saharan Africa, causing a mortality of 20–30% in vulnerable children below 5 years of age. In these settings, where routine surveillance for antimicrobial resistance is rare or non-existent, reports of 50–75% multidrug resistance (MDR) in NTS are common, including strains of NTS also resistant to flouroquinolones and 3rd generation cephalosporins. Typhoid (enteric) fever caused by Salmonella Typhi and Salmonella Paratyphi A remains a major public health problem in many parts of Asia and Africa. Currently over a third of isolates in many endemic areas are MDR, and diminished susceptibility or resistance to fluoroquinolones, the drugs of choice for MDR cases over the last decade is an increasing problem. The situation is particularly worrying in resource-limited settings where the few remaining effective antimicrobials are either unavailable or altogether too expensive to be afforded by either the general public or by public health services. Although the prudent use of effective antimicrobials, improved hygiene and sanitation and the discovery of new antimicrobial agents may offer hope for the management of invasive salmonella infections, it is essential to consider other interventions including the wider use of WHO recommended typhoid vaccines and the acceleration of trials for novel iNTS vaccines. The main objective of this review is to describe existing data on the prevalence and epidemiology of antimicrobial resistant invasive Salmonella infections and how this affects the management of these infections, especially in endemic developing countries. PMID:25912288

  6. Antimicrobial resistance and management of invasive Salmonella disease.

    PubMed

    Kariuki, Samuel; Gordon, Melita A; Feasey, Nicholas; Parry, Christopher M

    2015-06-19

    Invasive Salmonella infections (typhoidal and non-typhoidal) cause a huge burden of illness estimated at nearly 3.4 million cases and over 600,000 deaths annually especially in resource-limited settings. Invasive non-typhoidal Salmonella (iNTS) infections are particularly important in immunosuppressed populations especially in sub-Saharan Africa, causing a mortality of 20-30% in vulnerable children below 5 years of age. In these settings, where routine surveillance for antimicrobial resistance is rare or non-existent, reports of 50-75% multidrug resistance (MDR) in NTS are common, including strains of NTS also resistant to flouroquinolones and 3rd generation cephalosporins. Typhoid (enteric) fever caused by Salmonella Typhi and Salmonella Paratyphi A remains a major public health problem in many parts of Asia and Africa. Currently over a third of isolates in many endemic areas are MDR, and diminished susceptibility or resistance to fluoroquinolones, the drugs of choice for MDR cases over the last decade is an increasing problem. The situation is particularly worrying in resource-limited settings where the few remaining effective antimicrobials are either unavailable or altogether too expensive to be afforded by either the general public or by public health services. Although the prudent use of effective antimicrobials, improved hygiene and sanitation and the discovery of new antimicrobial agents may offer hope for the management of invasive salmonella infections, it is essential to consider other interventions including the wider use of WHO recommended typhoid vaccines and the acceleration of trials for novel iNTS vaccines. The main objective of this review is to describe existing data on the prevalence and epidemiology of antimicrobial resistant invasive Salmonella infections and how this affects the management of these infections, especially in endemic developing countries.

  7. Infections, bacterial resistance, and antimicrobial stewardship: the emerging role of hospitalists.

    PubMed

    Rosenberg, David J

    2012-01-01

    The care of patients with serious infections both within and outside healthcare settings is increasingly complicated by the high prevalence of resistant or multidrug-resistant (MDR) pathogens. Moreover, infections caused by MDR versus susceptible bacteria or other pathogens are associated with significantly higher mortality, length of hospital stay, and healthcare costs. Antimicrobial misuse or overuse is the primary driver for development of antimicrobial resistance, suggesting that better use of antimicrobials will translate into improved patient outcomes, more efficient use of hospital resources, and lowered healthcare costs. Antimicrobial stewardship refers to the various practices and procedures utilized to optimize antimicrobial use. The primary goal of antimicrobial stewardship is to improve patient outcomes and lower antimicrobial resistance and other unintended consequences of antimicrobial therapy. Secondary goals are to reduce length of hospital stays and healthcare-related costs. Hospitalists are increasingly involved in the care of hospitalized patients throughout the United States. Expertise in managing conditions requiring hospitalization, and experience in quality improvement across a wide range of clinical conditions, make hospitalists well positioned to participate in the development and implementation of hospital-based antimicrobial stewardship programs designed to improve patient outcomes, reduce antimicrobial resistance, and provide more efficient and lower-cost hospital care.

  8. Infections, bacterial resistance, and antimicrobial stewardship: the emerging role of hospitalists.

    PubMed

    Rosenberg, David J

    2012-01-01

    The care of patients with serious infections both within and outside healthcare settings is increasingly complicated by the high prevalence of resistant or multidrug-resistant (MDR) pathogens. Moreover, infections caused by MDR versus susceptible bacteria or other pathogens are associated with significantly higher mortality, length of hospital stay, and healthcare costs. Antimicrobial misuse or overuse is the primary driver for development of antimicrobial resistance, suggesting that better use of antimicrobials will translate into improved patient outcomes, more efficient use of hospital resources, and lowered healthcare costs. Antimicrobial stewardship refers to the various practices and procedures utilized to optimize antimicrobial use. The primary goal of antimicrobial stewardship is to improve patient outcomes and lower antimicrobial resistance and other unintended consequences of antimicrobial therapy. Secondary goals are to reduce length of hospital stays and healthcare-related costs. Hospitalists are increasingly involved in the care of hospitalized patients throughout the United States. Expertise in managing conditions requiring hospitalization, and experience in quality improvement across a wide range of clinical conditions, make hospitalists well positioned to participate in the development and implementation of hospital-based antimicrobial stewardship programs designed to improve patient outcomes, reduce antimicrobial resistance, and provide more efficient and lower-cost hospital care. Journal of Hospital Medicine 2012;7:S34-S43. © 2012 Society of Hospital Medicine.

  9. Antimicrobial resistance: One Health, one problem.

    PubMed

    Clark, Kathryn

    2014-11-29

    The roles that the medical and veterinary professions can play in tackling antimicrobial resistance were discussed at the BVA Congress at the London Vet Show last week. It was clear from the debate that, while action is already being taken, much more needs to be done by both professions in the UK and overseas. Kathryn Clark reports.

  10. Evaluation of antimicrobial resistance profiles of Salmonella isolates from broiler chickens at slaughter in Alberta, Canada.

    PubMed

    Mainali, C; McFall, M; King, R; Irwin, R

    2014-03-01

    Antimicrobial-resistant Salmonella species are threatening to become a serious public health problem. Therefore, surveillance and prudent use of antimicrobials is needed in both the agricultural and human health sectors. The aim of this study was to describe the antimicrobial susceptibility profiles of Salmonella isolates recovered from healthy broiler chickens at slaughter from November 2004 to April 2005. Salmonella isolates recovered from 36 broiler flocks in Alberta, Canada, were serotyped and tested for antimicrobial susceptibility against 15 antimicrobials. Of 272 Salmonella isolates tested, 64.0% were resistant to one or more antimicrobials, 10.0% were resistant to three or more antimicrobials, and 1.8% were resistant to five antimicrobials. All isolates were susceptible to amikacin, amoxicillin-clavulanic acid, ceftiofur, cefoxitin, ceftriaxone, ciprofloxacin, and nalidixic acid. The highest prevalence of resistance was to tetracycline (54.8%), followed by streptomycin (24.2%) and sulfisoxazole (8.4%). The most common multiantimicrobial resistance patterns were to streptomycin-tetracycline (24.3%), streptomycin-sulfisoxazole-tetracycline (6.6%), and ampicillin-streptomycin-sulfisoxazole-tetracycline (3.7%). The strongest associations were observed between resistance to kanamycin and tetracycline (odds ratio = 65.7, P = 0.001) and to ampicillin and sulfisoxazole (odds ratio = 62.9, P = 0.001). Salmonella Hadar and Salmonella Heidelberg were the two most common serovars accounting for 40.4 and 13.6% of the total isolates, respectively. Eighty-one percent and 12.7% of Salmonella Hadar isolates and 62.0 and 8.1% of Salmonella Heidelberg isolates were resistant to 1 or more and three or more antimicrobials, respectively. The flock level prevalence of resistance ranged from 5.6% for trimethoprim-sulfamethoxazole to 83.3% for tetracycline. This study provides baseline information on antimicrobial susceptibility of Salmonella isolates of broiler chickens at

  11. Boosting salt resistance of short antimicrobial peptides.

    PubMed

    Chu, Hung-Lun; Yu, Hui-Yuan; Yip, Bak-Sau; Chih, Ya-Han; Liang, Chong-Wen; Cheng, Hsi-Tsung; Cheng, Jya-Wei

    2013-08-01

    The efficacies of many antimicrobial peptides are greatly reduced under high salt concentrations, therefore limiting their use as pharmaceutical agents. Here, we describe a strategy to boost salt resistance and serum stability of short antimicrobial peptides by adding the nonnatural bulky amino acid β-naphthylalanine to their termini. The activities of the short salt-sensitive tryptophan-rich peptide S1 were diminished at high salt concentrations, whereas the activities of its β-naphthylalanine end-tagged variants were less affected.

  12. Antimicrobial Resistance in Wildlife: Implications for Public Health.

    PubMed

    Carroll, D; Wang, J; Fanning, S; McMahon, B J

    2015-11-01

    The emergence and spread of antimicrobial-resistant (AMR) bacteria in natural environments is a major concern with serious implications for human and animal health. The aim of this study was to determine the prevalence of AMR Escherichia coli (E. coli) in wild birds and mammalian species. Thirty faecal samples were collected from each of the following wildlife species: herring gulls (Larus argentatus), black-headed gulls (Larus ridibundus), lesser black-back gulls (Larus fuscus), hybrid deer species (Cervus elaphus x Cervus nippon) and twenty-six from starlings (Sturnus vulgaris). A total of 115 E. coli isolates were isolated from 81 of 146 samples. Confirmed E. coli isolates were tested for their susceptibility to seven antimicrobial agents by disc diffusion. In total, 5.4% (8/146) of samples exhibited multidrug-resistant phenotypes. The phylogenetic group and AMR-encoding genes of all multidrug resistance isolates were determined by PCR. Tetracycline-, ampicillin- and streptomycin-resistant isolates were the most common resistant phenotypes. The following genes were identified in E. coli: bla(TEM), strA, tet(A) and tet(B). Plasmids were identified in all samples that exhibited multidrug-resistant phenotypes. This study indicates that wild birds and mammals may function as important host reservoirs and potential vectors for the spread of resistant bacteria and genetic determinants of AMR.

  13. Antimicrobial Resistance and Virulence Characterization among Escherichia coli Clinical Isolates Causing Severe Obstetric Infections in Pregnant Women

    PubMed Central

    Guiral, Elisabet; Sáez-López, Emma; Bosch, Jordi; Goncé, Anna; López, Marta; Sanz, Sergi; Vila, Jordi

    2015-01-01

    The virulence markers and the antimicrobial resistance profiles of 78 Escherichia coli isolates causing obstetric infections accompanied by sepsis or not were studied. Adhesion-related virulence factors were the most prevalent markers. Low rates of resistance to the antimicrobial agents used as first-line therapy suggest their correct implementation in stewardship guidelines. PMID:25740771

  14. Industrial food animal production, antimicrobial resistance, and human health.

    PubMed

    Silbergeld, Ellen K; Graham, Jay; Price, Lance B

    2008-01-01

    Antimicrobial resistance is a major public health crisis, eroding the discovery of antimicrobials and their application to clinical medicine. There is a general lack of knowledge of the importance of agricultural antimicrobial use as a factor in antimicrobial resistance even among experts in medicine and public health. This review focuses on agricultural antimicrobial drug use as a major driver of antimicrobial resistance worldwide for four reasons: It is the largest use of antimicrobials worldwide; much of the use of antimicrobials in agriculture results in subtherapeutic exposures of bacteria; drugs of every important clinical class are utilized in agriculture; and human populations are exposed to antimicrobial-resistant pathogens via consumption of animal products as well as through widespread release into the environment.

  15. Low Rates of Antimicrobial-Resistant Enterobacteriaceae in Wildlife in Taï National Park, Côte d’Ivoire, Surrounded by Villages with High Prevalence of Multiresistant ESBL-Producing Escherichia coli in People and Domestic Animals

    PubMed Central

    Albrechtova, Katerina; Papousek, Ivo; De Nys, Helene; Pauly, Maude; Anoh, Etile; Mossoun, Arsene; Dolejska, Monika; Masarikova, Martina; Metzger, Sonya; Couacy-Hymann, Emmanuel; Akoua-Koffi, Chantal; Wittig, Roman M.; Klimes, Jiri; Cizek, Alois; Leendertz, Fabian H.; Literak, Ivan

    2014-01-01

    Antimicrobial resistance genes can be found in all ecosystems, including those where antibiotic selective pressure has never been exerted. We investigated resistance genes in a collection of faecal samples of wildlife (non-human primates, mice), people and domestic animals (dogs, cats) in Côte d’Ivoire; in the chimpanzee research area of Taï National Park (TNP) and adjacent villages. Single bacteria isolates were collected from antibiotic-containing agar plates and subjected to molecular analysis to detect Enterobacteriaceae isolates with plasmid-mediated genes of extended-spectrum beta-lactamases (ESBLs) and plasmid-mediated quinolone resistance (PMQR). While the prevalence of ESBL-producing E. coli in the villages was 27% in people (n = 77) and 32% in dogs (n = 38), no ESBL-producer was found in wildlife of TNP (n = 75). PMQR genes, mainly represented by qnrS1, were also present in human- and dog-originating isolates from the villages (36% and 42% in people and dogs, respectively), but no qnrS has been found in the park. In TNP, different variants of qnrB were detected in Citrobacter freundii isolates originating non-human primates and mice. In conclusion, ESBL and PMQR genes frequently found in humans and domestic animals in the villages were rather exceptional in wildlife living in the protected area. Although people enter the park, the strict biosecurity levels they are obliged to follow probably impede transmission of bacteria between them and wildlife. PMID:25474243

  16. Antimicrobial resistance trends among Escherichia coli isolates obtained from dairy cattle in the northeastern United States, 2004-2011.

    PubMed

    Cummings, Kevin J; Aprea, Victor A; Altier, Craig

    2014-01-01

    Monitoring antimicrobial resistance trends among bacteria isolated from food animals and people is necessary to inform risk analyses and guide public policy regarding antimicrobial use. Our objectives were to describe the antimicrobial resistance status of Escherichia coli isolates from dairy cattle in the northeastern United States and to identify trends in resistance to selected antimicrobial agents over time. We collected data retrospectively for all bovine E. coli isolates that were obtained from samples submitted to Cornell University's Animal Health Diagnostic Center between January 1, 2004 and December 31, 2011. We investigated temporal trends in the prevalence of resistant E. coli for each antimicrobial agent using the Cochran-Armitage trend test. Antimicrobial susceptibility testing was performed on 3373 bovine E. coli isolates from clinical samples submitted during the study period. Overall resistance to each antimicrobial agent ranged from 2.7% (enrofloxacin) to 91.3% (oxytetracycline). There was evidence of a significantly decreasing trend in prevalence of resistance to several agents: chlortetracycline, florfenicol, neomycin, oxytetracycline, spectinomycin, and trimethoprim/sulfamethoxazole. However, a significantly increasing trend in prevalence of resistance to enrofloxacin was also evident. These results do not support the idea that current antimicrobial use practices on dairy operations are driving a general increase in the emergence and dissemination of drug-resistant E. coli in the region served by the laboratory. However, resistance to some drugs remained consistently high during the study period, and increasing resistance to enrofloxacin is a key area of concern. PMID:24134668

  17. Antimicrobial resistance determinant microarray for analysis of multi-drug resistant isolates

    NASA Astrophysics Data System (ADS)

    Taitt, Chris Rowe; Leski, Tomasz; Stenger, David; Vora, Gary J.; House, Brent; Nicklasson, Matilda; Pimentel, Guillermo; Zurawski, Daniel V.; Kirkup, Benjamin C.; Craft, David; Waterman, Paige E.; Lesho, Emil P.; Bangurae, Umaru; Ansumana, Rashid

    2012-06-01

    The prevalence of multidrug-resistant infections in personnel wounded in Iraq and Afghanistan has made it challenging for physicians to choose effective therapeutics in a timely fashion. To address the challenge of identifying the potential for drug resistance, we have developed the Antimicrobial Resistance Determinant Microarray (ARDM) to provide DNAbased analysis for over 250 resistance genes covering 12 classes of antibiotics. Over 70 drug-resistant bacteria from different geographic regions have been analyzed on ARDM, with significant differences in patterns of resistance identified: genes for resistance to sulfonamides, trimethoprim, chloramphenicol, rifampin, and macrolide-lincosamidesulfonamide drugs were more frequently identified in isolates from sources in Iraq/Afghanistan. Of particular concern was the presence of genes responsible for resistance to many of the last-resort antibiotics used to treat war traumaassociated infections.

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

    PubMed

    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

    2013-07-01

    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

  19. Antimicrobial Resistance in the Food Chain: A Review

    PubMed Central

    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

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

    PubMed

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

    2013-06-28

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

  1. Resistance to Antimicrobial Peptides in Vibrios

    PubMed Central

    Destoumieux-Garzón, Delphine; Duperthuy, Marylise; Vanhove, Audrey Sophie; Schmitt, Paulina; Wai, Sun Nyunt

    2014-01-01

    Vibrios are associated with a broad diversity of hosts that produce antimicrobial peptides (AMPs) as part of their defense against microbial infections. In particular, vibrios colonize epithelia, which function as protective barriers and express AMPs as a first line of chemical defense against pathogens. Recent studies have shown they can also colonize phagocytes, key components of the animal immune system. Phagocytes infiltrate infected tissues and use AMPs to kill the phagocytosed microorganisms intracellularly, or deliver their antimicrobial content extracellularly to circumvent tissue infection. We review here the mechanisms by which vibrios have evolved the capacity to evade or resist the potent antimicrobial defenses of the immune cells or tissues they colonize. Among their strategies to resist killing by AMPs, primarily vibrios use membrane remodeling mechanisms. In particular, some highly resistant strains substitute hexaacylated Lipid A with a diglycine residue to reduce their negative surface charge, thereby lowering their electrostatic interactions with cationic AMPs. As a response to envelope stress, which can be induced by membrane-active agents including AMPs, vibrios also release outer membrane vesicles to create a protective membranous shield that traps extracellular AMPs and prevents interaction of the peptides with their own membranes. Finally, once AMPs have breached the bacterial membrane barriers, vibrios use RND efflux pumps, similar to those of other species, to transport AMPs out of their cytoplasmic space. PMID:27025756

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

    PubMed

    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.

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

    PubMed Central

    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

  4. Bacterial resistance to antimicrobials in urinary isolates.

    PubMed

    Muratani, Tetsuro; Matsumoto, Tetsuro

    2004-09-01

    Escherichia coli accounted for about 80% of organisms in uncomplicated urinary tract infections (UTIs), followed by Staphylococcus spp. especially Staphylococcus saprophyticus, and Proteus mirabilis. Against E. coli isolates from patients with uncomplicated UTI, faropenem was the most effective. Up to 1999, fluoroquinolone-resistant isolates were not observed in patients with uncomplicated UTI, but in 2001 fluoroquinolone-resistant E. coli isolates emerged and accounted for about 8%. Various types of organisms were isolated in patients with complicated UTI. Enterococcus faecalis, E. coli, and Pseudomonas aeruginosa were the three most frequent organisms isolated. These three organisms accounted for 44.6%. Amongst oral agents, faropenem showed the lowest rate of resistance against E. coli followed by cephems. The rates of highly fluoroquinolone-resistant and cefpodoxime-resistant E. coli isolates increased rapidly from 1998 to 2001. Fluoroquinolone-resistant P. aeruginosa isolates accounted for about 40% in 2001. Against this species, amikacin was the most effective antimicrobials among all agents tested. About 17% of Pseudomonas were resistant to carbapenem. Eight milligram per litre of ampicillin inhibited all E. faecalis isolates; about 60% of Enterococcus faecium were resistant to ampicillin. The rates of levofloxacin-resistant isolates of E. faecalis and E. faecium were 38 and 97% respectively. UTIs caused by vancomycin resistant enterococci (VRE) are rare in Japan. PMID:15364302

  5. Antimicrobial resistance of Campylobacter species isolated from edible bivalve molluscs purchased from Bangkok markets, Thailand.

    PubMed

    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. Prevalence and antimicrobial susceptibility of salmonellae isolates from reptiles in Taiwan.

    PubMed

    Chen, Chun-Yu; Chen, Wan-Ching; Chin, Shih-Chien; Lai, Yen-Hsueh; Tung, Kwong-Chung; Chiou, Chien-Shun; Hsu, Yuan-Man; Chang, Chao-Chin

    2010-01-01

    Pets, including reptiles, have been shown to be a source of Salmonella infection in humans. Due to increasing popularity and variety of exotic reptiles as pets in recent years, more human clinical cases of reptile-associated Salmonella infection have been identified. However, limited information is available with regard to serotypes in different reptiles (turtles, snakes, and lizards) and antimicrobial resistance of Salmonella in pet reptiles. The current study was thus conducted to determine the prevalence of Salmonella colonization in pet reptiles. Salmonella organisms were isolated from 30.9% of 476 reptiles investigated. The isolation prevalences were 69.7% (23/33), 62.8% (27/43), and 24.3% (97/400) in snakes, lizards, and turtles, respectively. A total of 44 different Salmonella serovars were identified. Compared with S. Heron, Bredeney, Treforest, and 4,[5],12:i:-, S. Typhimurium isolates were resistant to many antimicrobials tested, and notably 61.1% of the isolates were resistant to cephalothin. The results indicated that raising reptiles as pets could be a possible source of Salmonella infection in humans, particularly zoonotic Salmonella serovars such as S. Typhimurium that may be resistant to antimicrobials.

  7. Antimicrobial drug use and antimicrobial resistance in enteric bacteria among cattle from Alberta feedlots.

    PubMed

    Rao, Sangeeta; Van Donkersgoed, Joyce; Bohaychuk, Valerie; Besser, Thomas; Song, Xin-Ming; Wagner, Bruce; Hancock, Dale; Renter, David; Dargatz, David; Morley, Paul S

    2010-04-01

    The purpose of this study was to determine whether antimicrobial resistance (AMR) in foodborne pathogens (Escherichia coli O157, Salmonella, and Campylobacter) and non-type-specific E. coli obtained from fecal samples of feedlot cattle was associated with antimicrobial drug (AMD) use. A secondary objective was to determine if AMR in non-type-specific E. coli could be used as a predictor of AMR in foodborne pathogens. Fecal samples were collected from pen floors in 21 Alberta feedlots during March through December 2004, and resistance prevalence was estimated by season (Spring, Fall) and cattle type (fewest days-on-feed and closest to slaughter). AMD exposures were obtained by calculating therapeutic animal daily doses for each drug before sampling from feedlot records. Generalized linear mixed models were used to investigate the relationship between each AMR and AMD use. Non-type-specific E. coli was commonly recovered from fecal samples (88.62%), and the highest prevalence of resistance was found toward tetracycline (53%), streptomycin (28%), and sulfadiazine (48%). Campylobacter jejuni was recovered from 55.3% of the fecal samples, and resistance was generally less for the drugs that were evaluated (doxycycline 38.1%, ciprofloxacin 2.6%, nalidixic acid 1.64%, erythromycin 1.2%). E. coli O157 and Salmonella were recovered much less frequently (7% and 1% prevalence, respectively). The prevalence of recovery for the bacteria studied varied between seasons and cattle types, as did patterns of AMR. Among non-type-specific E. coli, resistance to tetracycline, streptomycin, and sulfadiazine was found to be positively associated with in-feed exposure as well as injectable tetracycline, but these differences were relatively small and of questionable practical relevance. Among C. jejuni isolates, cattle type was significantly associated with doxycycline resistance. Results suggested that resistance in non-type-specific E. coli to chloramphenicol, trimethoprim

  8. Prevalence of Antimicrobial Resistant and Virulent Salmonella spp. in Treated Effluent and Receiving Aquatic Milieu of Wastewater Treatment Plants in Durban, South Africa.

    PubMed

    Odjadjare, Ejovwokoghene C; Olaniran, Ademola O

    2015-08-01

    In this study, we evaluated the impact of treated wastewater effluent from two wastewater treatment plants on the physicochemical parameters and Salmonella spp. load of receiving rivers. Presumptive Salmonella spp. were obtained at all sampled points including the discharge points, with counts ranging from 0 to 4.14 log cfu/mL at both plants. Turbidity, chemical and biological oxygen demand were found to be high and mostly above the required limit for treated wastewater discharge. However, recorded nitrate and phosphate values were very low. Of the 200 confirmed Salmonella spp. isolates recovered from the treated effluent and receiving surface waters, 93% harbored the spiC gene, 84% harbored the misL gene, and 87.5% harbored the orfL gene while 87% harbored the pipD gene. The antibiotic resistance profile revealed that the isolates were resistant to sulfamethoxazole, nalidixic acid and streptomycin, but susceptible to quinolones and third generation β-lactams. These results indicate that in South Africa treated effluents are still a major source of contamination of rivers with pathogens such as Salmonella. Appropriate steps by the regulatory authorities and workers at the treatment plants are needed to enforce stipulated guidelines in order to prevent pollution of surface water resources due to the discharge of poorly treated effluents. PMID:26295245

  9. Prevalence of Antimicrobial Resistant and Virulent Salmonella spp. in Treated Effluent and Receiving Aquatic Milieu of Wastewater Treatment Plants in Durban, South Africa

    PubMed Central

    Odjadjare, Ejovwokoghene C.; Olaniran, Ademola O.

    2015-01-01

    In this study, we evaluated the impact of treated wastewater effluent from two wastewater treatment plants on the physicochemical parameters and Salmonella spp. load of receiving rivers. Presumptive Salmonella spp. were obtained at all sampled points including the discharge points, with counts ranging from 0 to 4.14 log cfu/mL at both plants. Turbidity, chemical and biological oxygen demand were found to be high and mostly above the required limit for treated wastewater discharge. However, recorded nitrate and phosphate values were very low. Of the 200 confirmed Salmonella spp. isolates recovered from the treated effluent and receiving surface waters, 93% harbored the spiC gene, 84% harbored the misL gene, and 87.5% harbored the orfL gene while 87% harbored the pipD gene. The antibiotic resistance profile revealed that the isolates were resistant to sulfamethoxazole, nalidixic acid and streptomycin, but susceptible to quinolones and third generation β-lactams. These results indicate that in South Africa treated effluents are still a major source of contamination of rivers with pathogens such as Salmonella. Appropriate steps by the regulatory authorities and workers at the treatment plants are needed to enforce stipulated guidelines in order to prevent pollution of surface water resources due to the discharge of poorly treated effluents. PMID:26295245

  10. Prevalence of Antimicrobial Resistant and Virulent Salmonella spp. in Treated Effluent and Receiving Aquatic Milieu of Wastewater Treatment Plants in Durban, South Africa.

    PubMed

    Odjadjare, Ejovwokoghene C; Olaniran, Ademola O

    2015-08-18

    In this study, we evaluated the impact of treated wastewater effluent from two wastewater treatment plants on the physicochemical parameters and Salmonella spp. load of receiving rivers. Presumptive Salmonella spp. were obtained at all sampled points including the discharge points, with counts ranging from 0 to 4.14 log cfu/mL at both plants. Turbidity, chemical and biological oxygen demand were found to be high and mostly above the required limit for treated wastewater discharge. However, recorded nitrate and phosphate values were very low. Of the 200 confirmed Salmonella spp. isolates recovered from the treated effluent and receiving surface waters, 93% harbored the spiC gene, 84% harbored the misL gene, and 87.5% harbored the orfL gene while 87% harbored the pipD gene. The antibiotic resistance profile revealed that the isolates were resistant to sulfamethoxazole, nalidixic acid and streptomycin, but susceptible to quinolones and third generation β-lactams. These results indicate that in South Africa treated effluents are still a major source of contamination of rivers with pathogens such as Salmonella. Appropriate steps by the regulatory authorities and workers at the treatment plants are needed to enforce stipulated guidelines in order to prevent pollution of surface water resources due to the discharge of poorly treated effluents.

  11. Antimicrobial resistance: A public health challenge

    PubMed Central

    Jindal, A.K.; Pandya, Kapil; Khan, I.D.

    2015-01-01

    Antimicrobial resistance has become a global concern. Though an evolutionary phenomenon, it is promulgated by faulty human behaviours. It is a growing concern ever since first reported in 1940s. Today, a plethora of newer generation antimicrobials have become ineffective against previously susceptible organisms. This is a huge challenge for health care managers all across the globe, compounded by the “discovery void” in the field of development of new antibiotics. If proper steps are not taken presently, the lurking fear of reaching a therapeutic dead end will become a reality. This paper aims at describing the pandemic of AMR from a public health perspective and suggesting strategies to deal with it in an effective and collaborative manner. PMID:25859082

  12. Antimicrobial resistance: A public health challenge.

    PubMed

    Jindal, A K; Pandya, Kapil; Khan, I D

    2015-04-01

    Antimicrobial resistance has become a global concern. Though an evolutionary phenomenon, it is promulgated by faulty human behaviours. It is a growing concern ever since first reported in 1940s. Today, a plethora of newer generation antimicrobials have become ineffective against previously susceptible organisms. This is a huge challenge for health care managers all across the globe, compounded by the "discovery void" in the field of development of new antibiotics. If proper steps are not taken presently, the lurking fear of reaching a therapeutic dead end will become a reality. This paper aims at describing the pandemic of AMR from a public health perspective and suggesting strategies to deal with it in an effective and collaborative manner. PMID:25859082

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

    PubMed Central

    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

  14. Salt-resistant short antimicrobial peptides.

    PubMed

    Mohanram, Harini; Bhattacharjya, Surajit

    2016-05-01

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

  15. Antimicrobial resistance in commensal Escherichia coli isolated from animals at slaughter

    PubMed Central

    Wasyl, Dariusz; Hoszowski, Andrzej; Zając, Magdalena; Szulowski, Krzysztof

    2013-01-01

    Monitoring of antimicrobial resistance in commensal Escherichia coli (N = 3430) isolated from slaughtered broilers, laying hens, turkeys, swine, and cattle in Poland has been run between 2009 and 2012. Based on minimal inhibitory concentration (MIC) microbiological resistance to each of 14 tested antimicrobials was found reaching the highest values for tetracycline (43.3%), ampicillin (42.3%), and ciprofloxacin (39.0%) whereas the lowest for colistin (0.9%), cephalosporins (3.6 ÷ 3.8%), and florfenicol (3.8%). The highest prevalence of resistance was noted in broiler and turkey isolates, whereas it was rare in cattle. That finding along with resistance patterns specific to isolation source might reflect antimicrobial consumption, usage preferences or management practices in specific animals. Regression analysis has identified changes in prevalence of microbiological resistance and shifts of MIC values. Critically important fluoroquinolone resistance was worrisome in poultry isolates, but did not change over the study period. The difference (4.7%) between resistance to ciprofloxacin and nalidixic acid indicated the scale of plasmid-mediated quinolone resistance. Cephalosporin resistance were found in less than 3.8% of the isolates but an increasing trends were observed in poultry and MIC shift in the ones from cattle. Gentamycin resistance was also increasing in E. coli of turkey and cattle origin although prevalence of streptomycin resistance in laying hens decreased considerably. Simultaneously, decreasing MIC for phenicols observed in cattle and layers isolates as well as tetracycline values in E. coli from laying hens prove that antimicrobial resistance is multivariable phenomenon not only directly related to antimicrobial usage. Further studies should elucidate the scope of commensal E. coli as reservoirs of resistance genes, their spread and possible threats for human and animal health. PMID:23935596

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

    PubMed

    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. PMID:26414105

  17. Application of a plasmid classification system to determine prevalence of replicon families among multidrug resistant enterococci

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The presence and transfer of plasmids from commensal bacteria to more pathogenic bacteria may contribute to dissemination of antimicrobial resistance. However, prevalence of plasmids from commensal bacteria in food animals such as the enterococci remains largely unknown. In this study, the prevale...

  18. Is Antimicrobial Resistance a Slowly Emerging Disaster?

    PubMed Central

    Viens, A. M.

    2015-01-01

    The problem of antimicrobial resistance is so dire that people are predicting that the era of antibiotics may be coming to an end, ushering in a ‘post-antibiotic’ era. A comprehensive policy response is therefore urgently needed. A part of this response will require framing the problem in such a way that adequately reflects its nature as well as encompassing an approach that has the best prospect of success. This paper considers framing the problem as a slowly emerging disaster, including its potential benefits and difficulties, from a conceptual and policy perspective. PMID:26566396

  19. Antimicrobial Resistance Prediction in PATRIC and RAST.

    PubMed

    Davis, James J; Boisvert, Sébastien; Brettin, Thomas; Kenyon, Ronald W; Mao, Chunhong; Olson, Robert; Overbeek, Ross; Santerre, John; Shukla, Maulik; Wattam, Alice R; Will, Rebecca; Xia, Fangfang; Stevens, Rick

    2016-01-01

    The emergence and spread of antimicrobial resistance (AMR) mechanisms in bacterial pathogens, coupled with the dwindling number of effective antibiotics, has created a global health crisis. Being able to identify the genetic mechanisms of AMR and predict the resistance phenotypes of bacterial pathogens prior to culturing could inform clinical decision-making and improve reaction time. At PATRIC (http://patricbrc.org/), we have been collecting bacterial genomes with AMR metadata for several years. In order to advance phenotype prediction and the identification of genomic regions relating to AMR, we have updated the PATRIC FTP server to enable access to genomes that are binned by their AMR phenotypes, as well as metadata including minimum inhibitory concentrations. Using this infrastructure, we custom built AdaBoost (adaptive boosting) machine learning classifiers for identifying carbapenem resistance in Acinetobacter baumannii, methicillin resistance in Staphylococcus aureus, and beta-lactam and co-trimoxazole resistance in Streptococcus pneumoniae with accuracies ranging from 88-99%. We also did this for isoniazid, kanamycin, ofloxacin, rifampicin, and streptomycin resistance in Mycobacterium tuberculosis, achieving accuracies ranging from 71-88%. This set of classifiers has been used to provide an initial framework for species-specific AMR phenotype and genomic feature prediction in the RAST and PATRIC annotation services. PMID:27297683

  20. Antimicrobial resistance prediction in PATRIC and RAST

    DOE PAGES

    Davis, James J.; Boisvert, Sebastien; Brettin, Thomas; Kenyon, Ronald W.; Mao, Chunhong; Olson, Robert; Overbeek, Ross; Santerre, John; Shukla, Maulik; Wattam, Alice R.; et al

    2016-06-14

    The emergence and spread of antimicrobial resistance (AMR) mechanisms in bacterial pathogens, coupled with the dwindling number of effective antibiotics, has created a global health crisis. Being able to identify the genetic mechanisms of AMR and predict the resistance phenotypes of bacterial pathogens prior to culturing could inform clinical decision-making and improve reaction time. At PATRIC (http://patricbrc.org/), we have been collecting bacterial genomes with AMR metadata for several years. In order to advance phenotype prediction and the identification of genomic regions relating to AMR, we have updated the PATRIC FTP server to enable access to genomes that are binned bymore » their AMR phenotypes, as well as metadata including minimum inhibitory concentrations. Using this infrastructure, we custom built AdaBoost (adaptive boosting) machine learning classifiers for identifying carbapenem resistance in Acinetobacter baumannii, methicillin resistance in Staphylococcus aureus, and beta-lactam and co-trimoxazole resistance in Streptococcus pneumoniae with accuracies ranging from 88–99%. We also did this for isoniazid, kanamycin, ofloxacin, rifampicin, and streptomycin resistance in Mycobacterium tuberculosis, achieving accuracies ranging from 71–88%. Lastly, this set of classifiers has been used to provide an initial framework for species-specific AMR phenotype and genomic feature prediction in the RAST and PATRIC annotation services.« less

  1. Antimicrobial Resistance Prediction in PATRIC and RAST

    PubMed Central

    Davis, James J.; Boisvert, Sébastien; Brettin, Thomas; Kenyon, Ronald W.; Mao, Chunhong; Olson, Robert; Overbeek, Ross; Santerre, John; Shukla, Maulik; Wattam, Alice R.; Will, Rebecca; Xia, Fangfang; Stevens, Rick

    2016-01-01

    The emergence and spread of antimicrobial resistance (AMR) mechanisms in bacterial pathogens, coupled with the dwindling number of effective antibiotics, has created a global health crisis. Being able to identify the genetic mechanisms of AMR and predict the resistance phenotypes of bacterial pathogens prior to culturing could inform clinical decision-making and improve reaction time. At PATRIC (http://patricbrc.org/), we have been collecting bacterial genomes with AMR metadata for several years. In order to advance phenotype prediction and the identification of genomic regions relating to AMR, we have updated the PATRIC FTP server to enable access to genomes that are binned by their AMR phenotypes, as well as metadata including minimum inhibitory concentrations. Using this infrastructure, we custom built AdaBoost (adaptive boosting) machine learning classifiers for identifying carbapenem resistance in Acinetobacter baumannii, methicillin resistance in Staphylococcus aureus, and beta-lactam and co-trimoxazole resistance in Streptococcus pneumoniae with accuracies ranging from 88–99%. We also did this for isoniazid, kanamycin, ofloxacin, rifampicin, and streptomycin resistance in Mycobacterium tuberculosis, achieving accuracies ranging from 71–88%. This set of classifiers has been used to provide an initial framework for species-specific AMR phenotype and genomic feature prediction in the RAST and PATRIC annotation services. PMID:27297683

  2. The Ethical Significance of Antimicrobial Resistance

    PubMed Central

    Littmann, Jasper

    2015-01-01

    In this paper, we provide a state-of-the-art overview of the ethical challenges that arise in the context of antimicrobial resistance (AMR), which includes an introduction to the contributions to the symposium in this issue. We begin by discussing why AMR is a distinct ethical issue, and should not be viewed purely as a technical or medical problem. In the second section, we expand on some of these arguments and argue that AMR presents us with a broad range of ethical problems that must be addressed as part of a successful policy response to emerging drug resistance. In the third section, we discuss how some of these ethical challenges should be addressed, and we argue that this requires contributions from citizens, ethicists, policy makers, practitioners and industry. We conclude with an overview of steps that should be taken in moving forward and addressing the ethical problems of AMR. PMID:26566395

  3. Antimicrobial resistance in generic Escherichia coli isolated from swine fecal samples in 90 Alberta finishing farms

    PubMed Central

    Varga, Csaba; Rajíc, Andrijana; McFall, Margaret E.; Avery, Brent P.; Reid-Smith, Richard J.; Deckert, Anne; Checkley, Sylvia L.; McEwen, Scott A.

    2008-01-01

    The objective of this study was to determine the prevalence of antimicrobial resistance in generic Escherichia coli isolates obtained from 90 Alberta finisher swine farms. Up to 5 isolates were obtained from each of 269 pooled fecal samples and were classified as susceptible or resistant according to Clinical and Laboratory Standards Institute guidelines. Of the 1322 isolates, 166 (12.6%) were susceptible to all 15 antimicrobials. No resistance to amikacin, ceftiofur, ceftriaxone, or ciprofloxacin, antimicrobials of importance in human medicine, was observed. Relatively low frequencies of resistance were observed to gentamicin (1.1%), amoxicillin/clavulanic acid (0.7%), and cefoxitin (0.7%). Higher frequencies of resistance were observed for tetracycline (78.9%), sulfisoxazole (49.9%), streptomycin (49.6%), ampicillin (30.6%), chloramphenicol (17.6%), kanamycin (10%), and trimethoprim/sulfamethoxazole (6.4%). Among the isolates resistant to ≥ 2 antimicrobial classes, 20.8%, 20.6%, 18.2%, 7.0%, 1.8%, 0.2%, and 0.2% were resistant to 2, 3, 4, 5, 6, 7, and 8 antimicrobials, respectively. The most common multidrug-resistance patterns (resistance to ≥ 2 antimicrobial classes) were streptomycin-tetracycline (9.4%), streptomycin-sulfisoxazole-tetracycline (6.2%), and ampicillin-streptomycin-sulfisoxazole-tetracycline (6.1%). More clustering (higher intra-class correlation coefficients) in antimicrobial resistance was observed for isolates at the same visit than for isolates from different visits in the same farm, indicating that sampling more farms, testing fewer isolates per visits, and taking longer periods between visits may be appropriate and more efficient for a better understanding of potential shifts in resistance over time. PMID:18505207

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

    PubMed

    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.

  5. Plasmid-Mediated Antimicrobial Resistance in Staphylococci and Other Firmicutes.

    PubMed

    Schwarz, Stefan; Shen, Jianzhong; Wendlandt, Sarah; Fessler, Andrea T; Wang, Yang; Kadlec, Kristina; Wu, Cong-Ming

    2014-12-01

    In staphylococci and other Firmicutes, resistance to numerous classes of antimicrobial agents, which are commonly used in human and veterinary medicine, is mediated by genes that are associated with mobile genetic elements. The gene products of some of these antimicrobial resistance genes confer resistance to only specific members of a certain class of antimicrobial agents, whereas others confer resistance to the entire class or even to members of different classes of antimicrobial agents. The resistance mechanisms specified by the resistance genes fall into any of three major categories: active efflux, enzymatic inactivation, and modification/replacement/protection of the target sites of the antimicrobial agents. Among the mobile genetic elements that carry such resistance genes, plasmids play an important role as carriers of primarily plasmid-borne resistance genes, but also as vectors for nonconjugative and conjugative transposons that harbor resistance genes. Plasmids can be exchanged by horizontal gene transfer between members of the same species but also between bacteria belonging to different species and genera. Plasmids are highly flexible elements, and various mechanisms exist by which plasmids can recombine, form cointegrates, or become integrated in part or in toto into the chromosomal DNA or into other plasmids. As such, plasmids play a key role in the dissemination of antimicrobial resistance genes within the gene pool to which staphylococci and other Firmicutes have access. This chapter is intended to provide an overview of the current knowledge of plasmid-mediated antimicrobial resistance in staphylococci and other Firmicutes.

  6. Prevalence and antimicrobial susceptibility of Listeria monocytogenes on chicken carcasses in Bandung, Indonesia.

    PubMed

    Sugiri, Yoni Darmawan; Gölz, Greta; Meeyam, Tongkorn; Baumann, Maximilian P O; Kleer, Josef; Chaisowwong, Warangkhana; Alter, Thomas

    2014-08-01

    This study was conducted to determine the prevalence and quantify the number of Listeria monocytogenes in fresh chicken carcasses sold in traditional markets and supermarkets in Bandung, West Java, Indonesia, and to determine the antimicrobial resistance patterns of the isolated L. monocytogenes strains. The overall prevalence of L. monocytogenes in chicken carcasses was 15.8% (29/184). When comparing samples from traditional markets and supermarkets, no significant difference in the L. monocytogenes prevalence was detectable (15.2 versus 16.3%). Of the samples, 97.3% had L. monocytogenes counts <100 CFU/g, 2.2% had L. monocytogenes counts between 101 and 1,000 CFU/g, and 0.5% had L. monocytogenes counts of 1,001 to 10,000 CFU/g. Of the isolates, 27.6% were resistant to at least one of the 10 antimicrobials tested, with the major resistant phenotypes to penicillin (17.2%), ampicillin (6.9%), and erythromycin (6.9%). All 29 isolates recovered in this study were grouped into the molecular serogroup IIb, comprising the serovars 1/2b, 3b, and 7.

  7. Antimicrobial resistance: a global multifaceted phenomenon

    PubMed Central

    Prestinaci, Francesca; Pezzotti, Patrizio; Pantosti, Annalisa

    2015-01-01

    Antimicrobial resistance (AMR) is one of the most serious global public health threats in this century. The first World Health Organization (WHO) Global report on surveillance of AMR, published in April 2014, collected for the first time data from national and international surveillance networks, showing the extent of this phenomenon in many parts of the world and also the presence of large gaps in the existing surveillance. In this review, we focus on antibacterial resistance (ABR), which represents at the moment the major problem, both for the high rates of resistance observed in bacteria that cause common infections and for the complexity of the consequences of ABR. We describe the health and economic impact of ABR, the principal risk factors for its emergence and, in particular, we illustrate the highlights of four antibiotic-resistant pathogens of global concern – Staphylococcus aureus, Klebsiella pneumoniae, non-typhoidal Salmonella and Mycobacterium tuberculosis – for whom we report resistance data worldwide. Measures to control the emergence and the spread of ABR are presented. PMID:26343252

  8. A trend analysis of antimicrobial resistance in commensal Escherichia coli from several livestock species in Belgium (2011-2014).

    PubMed

    Hanon, Jean-Baptiste; Jaspers, Stijn; Butaye, Patrick; Wattiau, Pierre; Méroc, Estelle; Aerts, Marc; Imberechts, Hein; Vermeersch, Katie; Van der Stede, Yves

    2015-12-01

    A temporal trend analysis was performed on antimicrobial resistance data collected over 4 consecutive years (2011-2014) in the official Belgian antimicrobial resistance monitoring programme. Commensal Escherichia coli strains were isolated from faecal samples of four livestock categories (veal calves, young beef cattle, broiler chickens and slaughter pigs) and the trends of resistance profiles were analysed. The resistance prevalence remained high (>50%) during the study period for ampicillin in veal calves and chickens, for ciprofloxacin and nalidixic acid in chickens, for sulfamethoxazole in veal calves, chickens and pigs and for tetracycline in veal calves. Using logistic regression and Generalized Estimating Equation and after p value adjustment for multiple testing (Linear step-up method), statistically significant decreasing temporal trends were observed for several of the 11 tested antimicrobials in several livestock categories: in veal calves (10/11), in chickens (6/11) and in pigs (5/11). A significant increasing trend was observed for the prevalence of resistance to ciprofloxacin in chickens. Multi-resistance, considered as the resistance to at least three antimicrobials of different antibiotic classes, was observed in the four livestock categories but was significantly decreasing in veal calves, chickens and pigs. Overall, the prevalence of resistance and of multi-resistance was lowest in the beef cattle livestock category and highest in broiler chickens. These decreasing temporal trends of antimicrobial resistance might be due to a decrease of the total antimicrobial consumption for veterinary use in Belgium which was reported for the period between 2010 and 2013. The methodology and statistical tools developed in this study provide outputs which can detect shifts in resistance levels or resistance trends associated with particular antimicrobial classes and livestock categories. Such outputs can be used as objective evidence to evaluate the possible

  9. National Antimicrobial Resistance Monitoring System (NARMS) 2010 Report

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In an effort to prospectively monitor the emergence of antimicrobial resistance in zoonotic pathogens, the National Antimicrobial Resistance Monitoring System (NARMS) was established in 1996 by the Food and Drug Administration’s Center for Veterinary Medicine in collaboration with the Centers for Di...

  10. Antimicrobial resistance trends among Salmonella isolates obtained from dairy cattle in the northeastern United States, 2004-2011.

    PubMed

    Cummings, Kevin J; Perkins, Gillian A; Khatibzadeh, Sarah M; Warnick, Lorin D; Altier, Craig

    2013-04-01

    Monitoring antimicrobial resistance trends among bacteria isolated from food animals and people is necessary to inform public policy regarding appropriate antimicrobial use. Our objectives were to describe the antimicrobial resistance status of Salmonella isolates from dairy cattle in the northeastern United States and to identify trends in resistance to various antimicrobial agents over time. Data were collected retrospectively for all bovine Salmonella isolates that were obtained from samples submitted to Cornell University's Animal Health Diagnostic Center between January 1, 2004 and December 31, 2011. Temporal trends in the prevalence of resistant Salmonella were investigated for each antimicrobial agent using the Cochran-Armitage trend test. Antimicrobial susceptibility testing was performed on 2745 bovine Salmonella isolates from clinical samples submitted during the study period. Overall resistance to each antimicrobial agent ranged from 0% (amikacin, ciprofloxacin, and nalidixic acid) to 72.0% (sulfadimethoxine). There was evidence of a significantly decreasing trend in prevalence of resistance to most agents: amoxicillin/clavulanic acid (AUG), ampicillin (AMP), cefoxitin (FOX), ceftiofur (TIO), ceftriaxone (AXO), chloramphenicol (CHL), chlortetracycline (CTET), florfenicol (FFN), kanamycin (KAN), neomycin (NEO), oxytetracycline (OXY), spectinomycin (SPE), streptomycin (STR), sulfadimethoxine (SDM), sulfisoxazole (FIS), and tetracycline (TET). Among the 265 isolates that were tested using the National Antimicrobial Resistance Monitoring System (NARMS) panel, the most common resistance patterns were pansusceptible (54.0%), AUG-AMP-FOX-TIO-AXO-CHL-KAN-STR-FIS-TET (18.1%), and AUG-AMP-FOX-TIO-AXO-CHL-STR-FIS-TET (12.1%). Increasing prevalence of S. enterica serovar Cerro over the course of the study period presumably had an impact on the observed resistance trends. Nevertheless, these results do not support the notion that the current level of antimicrobial

  11. Antimicrobial resistance and molecular epidemiology of streptococci from bovine mastitis.

    PubMed

    Rato, Márcia G; Bexiga, Ricardo; Florindo, Carlos; Cavaco, Lina M; Vilela, Cristina L; Santos-Sanches, Ilda

    2013-01-25

    Streptococcus agalactiae (Group B Streptococcus, GBS), Streptococcus dysgalactiae subsp. dysgalactiae (Group C Streptococcus, GCS) and Streptococcus uberis are relevant mastitis pathogens, a highly prevalent and costly disease in dairy industry due to antibiotherapy and loss in milk production. The aims of this study were the evaluation of antimicrobial drug resistance patterns, particularly important for streptococcal mastitis control and the identification of strain molecular features. Antimicrobial resistance was assessed by disk diffusion against amoxicillin-clavulanic acid, cefazolin, cefoperazone, pirlimycin-PRL, rifaximin, streptomycin, chloramphenicol, erythromycin-ERY, gentamicin, tetracycline-TET and vancomycin. Genotypic relationships were identified using pulsed-field gel electrophoresis (PFGE), macrolide and/or tetracycline resistance gene profiling, GBS capsular typing, GBS virulence gene profiling and GBS and S. uberis multi locus sequence typing (MLST). The majority of the isolates were susceptible to all drugs except to aminoglycoside, macrolide, lincosamide and tetracycline. Close to half of the TET resistant isolates have tetO and tetK and almost all ERY-PRL resistant isolates have ermB. A high degree of intra-species polymorphism was found for GCS. The GBS belonged to ST-2, -554, -61, -23 lineages and five new molecular serotypes and human GBS insertion sequences in the cpsE gene were found. Also, GBS of serotype V with scpB and lmb seem to be related with GBS isolates of human origin (same ST-2 and similar PFGE). Overall our results suggested that different therapeutic programs may have been implemented in the different farms and that in most cases clones were herd-specific. PMID:22964008

  12. Antimicrobial resistance: consideration as an adverse drug event.

    PubMed

    Martin, Steven J; Micek, Scott T; Wood, G Christopher

    2010-06-01

    Antimicrobial resistance has increased dramatically in the past 15 to 20 yrs and presents a patient safety concern unlike any other in the intensive care unit. Antimicrobial resistance in critically ill patients increases morbidity, mortality, length of hospital stay, and healthcare costs. Some organisms may have intrinsically high levels of resistance or may be spread between patients by poor infection control practices. However, a major driver of antimicrobial resistance is antibiotic use. As such, the development of antimicrobial resistance can often be thought of as an adverse drug event. This article explores the link between drug use, drug dosing, other selective pressures and resistance, and describes concepts to minimize the negative impact of antimicrobial therapy. Two broad themes of these concepts are minimizing the use of antibiotics whenever possible and optimizing antibiotic usage when they are needed. Strategies for minimizing the use of antimicrobials include using optimal diagnostic procedures to ensure the need for antimicrobials, streamlining or discontinuing therapy when possible based on culture results, and using the shortest duration of therapy needed for documented infections. Strategies for optimizing antimicrobial use include using optimal dosing based on the manufacturer's instructions and current pharmacodynamic data, guiding better prescribing based on local susceptibility patterns and formulary restriction, and avoiding drugs with more propensity to foster resistance.

  13. Antimicrobial-resistant bacterial populations and antimicrobial resistance genes obtained from environments impacted by livestock and municipal waste

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study compared the populations of antimicrobial-resistant bacteria and the repertoire of antimicrobial resistance genes in four environments: effluent of three municipal waste water treatment facilities, three cattle feedlot runoff catchment ponds, three swine waste lagoons, and two "low impact...

  14. Salmon Aquaculture and Antimicrobial Resistance in the Marine Environment

    PubMed Central

    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

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

    PubMed

    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.

  16. Occurrence of multidrug resistant Salmonella in antimicrobial-free (ABF) swine production systems.

    PubMed

    Thakur, Siddhartha; Tadesse, Daniel A; Morrow, Morgan; Gebreyes, Wondwossen A

    2007-12-15

    This cross-sectional study was conducted to determine the prevalence and antimicrobial resistance of Salmonella species in swine reared in the intensive (indoor) and extensive (outdoor) ABF production systems at farm and slaughter in North Carolina, U.S.A. We sampled a total of 279 pigs at farm (extensive 107; intensive 172) and collected 274 carcass swabs (extensive 124; intensive 150) at slaughter. Salmonella species were tested for their susceptibility against 12 antimicrobial agents using the Kirby-Bauer disk diffusion method. Serogrouping was done using polyvalent and group specific antisera. A total of 400 salmonellae were isolated in this study with a significantly higher Salmonella prevalence from the intensive (30%) than the extensive farms (0.9%) (P<0.001). At slaughter, significantly higher Salmonella was isolated at the pre- and post-evisceration stages from extensively (29% pre-evisceration and 33.3% post-evisceration) than the intensively (2% pre-evisceration and 6% post-evisceration) reared swine (P<0.001). The isolates were clustered in six serogroups including B, C, E1, E4, G and R. Highest frequency of antimicrobial resistance was observed against tetracycline (78.5%) and streptomycin (31.5%). A total of 13 antimicrobial resistance patterns were observed including the pentaresistant strains with ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, tetracycline resistance pattern observed only among isolates from the intensive farms (n=28) and all were serotype Salmonella typhimurium var. Copenhagen. In conclusion, this study shows that multidrug resistant Salmonella are prevalent in ABF production systems despite the absence of antimicrobial selection pressure. In addition, it also highlights the possible role played by slaughterhouse and other environmental factors in the contamination and dissemination of antimicrobial resistant Salmonella in ABF production systems. PMID:17644277

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

    PubMed

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

    1998-01-01

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

  18. CNS species and antimicrobial resistance in clinical and subclinical bovine mastitis.

    PubMed

    Waller, K Persson; Aspán, A; Nyman, A; Persson, Y; Andersson, U Grönlund

    2011-08-26

    Coagulase-negative staphylococci (CNS) are often associated with bovine mastitis. Knowledge about the relative importance of specific CNS species in different types of mastitis, and differences in antimicrobial resistance among CNS species is, however, scarce. Therefore, the aims of this study were to compare prevalence and antimicrobial susceptibility of CNS species in clinical and subclinical mastitis using material from two national surveys. Overall, Staphylococcus chromogenes and Staphylococcus epidermidis were the most common CNS species found followed by Staphylococcus simulans and Staphylococcus haemolyticus. S. epidermidis was significantly more prevalent in subclinical than in clinical mastitis, and a similar trend was observed for Staphylococcus saprophyticus, while Staphylococcus hyicus was significantly more common in clinical mastitis. The prevalence of β-lactamase producing isolates varied markedly between CNS species, and was significantly higher in S. epidermidis and S. haemolyticus (∼ 40%), than in S. simulans and S. chromogenes where none or a few of the isolates produced β-lactamase. Resistance to more than one antimicrobial substance occurred in 9% and 7% of the clinical and subclinical isolates, respectively. In conclusion, the distribution of CNS species differed between clinical and subclinical mastitis indicating inter-species variation of pathogenicity and epidemiology. Overall, the prevalence of antimicrobial resistance was low, but some variation between CNS species was observed. PMID:21561725

  19. Nationwide surveillance of antimicrobial resistance among Enterobacteriaceae in intensive care units in Taiwan.

    PubMed

    Jean, S-S; Hsueh, P-R; Lee, W-S; Chang, H-T; Chou, M-Y; Chen, I-S; Wang, J-H; Lin, C-F; Shyr, J-M; Ko, W-C; Wu, J-J; Liu, Y-C; Huang, W-K; Teng, L-J; Liu, C-Y

    2009-02-01

    To determine the antimicrobial resistance profiles among clinical isolates of Enterobacteriaceae in Taiwanese intensive care units (ICUs), a national surveillance of antibiotic resistance among important Enterobacteriaceae was conducted from September 2005 through November 2005 at the ICUs of ten major teaching hospitals in Taiwan. A total of 574 Enterobacteriaceae isolates recovered from various clinical samples of our ICU patients were submitted for in vitro test. Minimum inhibitory concentrations (MICs) of these isolates to 18 antimicrobial agents were determined by the broth microdilution method. The prevalences of Enterobacteriaceae isolates with phenotypic extended-spectrum beta-lactamase (ESBL) production were 26% in Klebsiella pneumoniae, 16% in Serratia marcescens, 14% in Escherichia coli, and 13% in Proteus mirabilis, in which a significantly rising prevalence of ESBL production among K. pneumoniae was noted (p = 0.002) when compared with a previous Taiwanese survey in 2000. Heterogeneous resistance to various fluoroquinolones was found among our Enterobacteriaceae isolates, except for Enterobacter cloacae. Emergence of ertapenem-resistant isolates of E. coli, K. pneumoniae, E. cloacae, and S. marcescens was noted. Gradually increasing rates of drug-resistant Enterobacteriaceae were noted in Taiwanese ICUs. Periodic surveillance of the evolutionary trend of antimicrobial resistance among ICU isolates is crucial for starting appropriately empirical antimicrobial therapy in the future. PMID:18716805

  20. Multilocus Sequence Typing and Antimicrobial Resistance of Campylobacter jejuni Isolated from Dairy Calves in Austria

    PubMed Central

    Klein-Jöbstl, Daniela; Sofka, Dmitri; Iwersen, Michael; Drillich, Marc; Hilbert, Friederike

    2016-01-01

    Human campylobacteriosis is primarily associated with poultry but also cattle. In this study, 55 Campylobacter jejuni strains isolated from 382 dairy calves’ feces were differentiated by multilocus sequence typing and tested for antimicrobial resistance. The most prevalent sequence type (ST) was ST883 (20.0%), followed by ST48 (14.5%), and ST50 (9.1%). In contrast to ST48 and ST50, ST883 has rarely been described in cattle previously. Furthermore, risk factor analysis was performed for the presence of the most prevalent STs in these calves. Multiple regression analysis revealed that the type of farm (organic vs. conventional) and calf housing (place, and individual vs. group) were identified as significantly (p < 0.05) associated with the presence of ST883 in calves, and ST50 was associated with calf diarrhea. Antimicrobial resistance was detected in 58.2% of the isolates. Most of the resistant isolates (81.3%) were resistant to more than one antimicrobial. Most frequently, resistance to ciprofloxacin (49.1%), followed by nalidixic acid (42.8%), and tetracycline (14.5%) was observed. The results of the present study support the hypothesis that dairy calves may serve as a potential reservoir for C. jejuni and pose a risk for transmission, including antimicrobial resistant isolates to the environment and to humans. PMID:26870027

  1. Antimicrobial resistance in fecal generic Escherichia coli and Salmonella spp. obtained from Ontario sheep flocks and associations between antimicrobial use and resistance.

    PubMed

    Scott, Lisa; Menzies, Paula; Reid-Smith, Richard J; Avery, Brent P; McEwen, Scott A; Moon, Catherine S; Berke, Olaf

    2012-04-01

    The purpose of this study was to examine the prevalence and patterns of antimicrobial resistance (AMR) in enteric bacteria obtained from Ontario sheep flocks, and associations between antimicrobial use (AMU) and AMR. Forty-nine sheep producers participated for a 1-year interval between 2006 and 2008. Two-hundred and eighty-three pooled fecal samples were collected from the flocks during initial and final visits. Up to 3 isolates of Salmonella spp. and generic E. coli per pooled fecal sample were tested for susceptibility to 15 antimicrobials. Resistance was infrequent among Salmonella (0%, n = 7 isolates) and low among E. coli (13.1%; n = 849) isolates. A small number of isolates were resistant to antimicrobials classified as being of very high importance to human health. Tetracycline resistance was most frequently observed (12.0%). Logistic regression was used to model potential AMU (qualitative and quantitative) risk factors for tetracycline resistance in generic E. coli from final visits. Qualitative analysis indicated that the use of injectable sulfonamides [including trimethoprim-sulfonamide combinations (TMS)] and tetracycline in the feed and water were significantly associated with tetracycline resistance (OR = 2.6, P = 0.01; and OR = 4.8, P ≤ 0.01, respectively). Quantitative analysis also indicated that TMS exposure rate was significantly associated with tetracycline resistance, which varied depending on the exposure rate. The exposure rate of tetracycline in the feed and water was only significant after the removal of one influential flock, warranting further research examining flocks with higher tetracycline exposure rates. Although the prevalence of AMR in participating flocks was relatively low, risk factors for resistance were identified.

  2. Loads and antimicrobial resistance of Campylobacter spp. on fresh chicken meat in Nueva Ecija, Philippines.

    PubMed

    Sison, F B; Chaisowwong, W; Alter, T; Tiwananthagorn, S; Pichpol, D; Lampang, K N; Baumann, M P O; Gölz, G

    2014-05-01

    This study was performed to determine the prevalence and to semiquantify Campylobacter spp. on chicken meat samples at 4 selected local wet markets in Nueva Ecija, Philippines, and to determine the antimicrobial resistance patterns of the Campylobacter isolates. Out of 120 chicken meat samples, 57 (47.5%) were Campylobacter spp. positive. The majority of isolated Campylobacter strains were identified as Campylobacter coli (54.4%) and 45.6% as Campylobacter jejuni. Most of these positive samples (52.6%) showed a very high quantitative Campylobacter contamination (most probable number > 2,400/g, lower confidence limit 580/g). For antimicrobial resistance testing, 44 C. coli/jejuni isolates were tested using the agar disk diffusion method. Out of these, 77.3% were resistant to ampicillin, followed by ciprofloxacin (70.4%), tetracycline (54.6%), erythromycin (20.2%), and gentamicin (11.4%). Of the isolates, 36.4% (n = 16) were resistant to 1 antimicrobial agent, 34.1% (n = 15) were resistance to 3 antimicrobial agents, 13.6% (n = 6) to 2 antimicrobial agents, 9.1% (n = 4) to 4 antimicrobial agents, and 6.8% (n = 3) to all 5 antimicrobial agents tested. Our data demonstrate a high contamination of fresh chicken meat with Campylobacter spp. at retail in the Philippines. The detected high Campylobacter prevalences and quantitative loads on chicken meat at retail in the Philippines highlight the need to implement efficient intervention measures along the food chain and to encourage sanitary handling of poultry meat.

  3. [Antimicrobial in nursing homes in a French region: point prevalence survey and consumption in 2012].

    PubMed

    Marquet, Aurélie; Thibaut, Sonia; Berrut, Gilles; Ballereau, Françoise

    2015-09-01

    Infectious diseases and bacterial resistance are gaining importance in nursing homes. A few studies about antibiotic (AB) consumption in nursing homes (NHs) already exist. A national survey was performed by the European surveillance of antimicrobial consumption with the aim of gaining insight in NHs care to all European countries. This study shows that the surveillance of AB use is not organised in continuous for many countries and have shown that the prevalence of infections in French nursing homes was 4.8%. In France, there is no national data collection system of AB consumption for NHs. Data were obtained from a point prevalence survey conducted in 2012 in 80 NHs. In total, 1.366 residents were included and 48 residents were treated with antimicrobials (3.5%). Antimicrobials were most frequently prescribed for the treatment of respiratory (45.8%) and urinary tract infections (27.1%). For 4 prescriptions, the indication was not found. Consumption datas for 52 NHs were collected. The AB consumption mediane was 39 defined daily dose/1.000 PD (DDD/1.000 PD). The mediane of AB consumption for the region was 39.4 DDD/1.000 PD. Coamoxi-clav is the main AB consumed (39%) followed by amoxicillin with 30%.

  4. Antimicrobial-resistant Campylobacter in the food chain in Mexico.

    PubMed

    Zaidi, Mussaret B; McDermott, Patrick F; Campos, Freddy D; Chim, Rodolfo; Leon, Magda; Vazquez, Gabriela; Figueroa, Gloria; Lopez, Estela; Contreras, Jesus; Estrada-Garcia, Teresa

    2012-09-01

    We describe prevalence and antimicrobial susceptibility results for thermophilic Campylobacter isolates collected from humans, food, and food-animals in an integrated food chain surveillance network in Mexico. From 2003 to 2006, stool samples were collected from children with diarrhea at state sentinel hospitals. Concurrently, fecal samples from asymptomatic children in kindergartens, as well as raw chicken, pork and beef from retail outlets, and food-animal intestines from slaughterhouses were all collected in 65 cities from four different states. C. jejuni was identified with a standardized hippurate test. Hippurate negative, indoxyl acetate positive isolates were classified as Campylobacter spp. Susceptibility testing was performed by agar dilution according to Clinical and Laboratory Standards Institute guidelines. A total of 1,259 C. jejuni and 1,797 Campylobacter spp. isolates were recovered from 11,811 samples. Chicken was significantly more contaminated for both intestinal samples (93.6%) and meat products (58.3%), compared with swine (71.4%)/pork (14.6%) samples, and cattle (25.1%)/beef (5.3%) samples (p<0.001). Campylobacter was recovered from 5.1% of children with diarrhea and from 3.2% of asymptomatic children. Chicken was significantly more likely to harbor ciprofloxacin-resistant C. jejuni (85.8%) than swine (62.5%, OR=3.6), cattle (39.8%, OR=9.3), or humans (58.2%, OR=4.4). No significant differences were found for ciprofloxacin-resistant Campylobacter spp. among food-animals, but the rate in food-animals was significantly higher than in humans (84% vs. 56.7%, OR=4.0). Swine was significantly more likely to harbor erythromycin-resistant C. jejuni (14.8%) than chicken (3.5%, OR=4.9), cattle (1.8%, OR=9.3), or humans (3.0%, OR=5.7), and was associated with higher rates of erythromycin-resistant Campylobacter spp. (41.9%) than chicken (10.5%, OR=6.1) and humans (11.9%, OR=5.3). The high resistance rates to ciprofloxacin preclude the use of

  5. Overview Of Antimicrobial Resistance In Food Borne Pathogens In The United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antimicrobial susceptibility testing remains an important tool as investigators devise ways to arrest the development of antimicrobial resistance, particularly in food borne bacteria. In 1996, the Food and Drug Administration (FDA) initiated the National Antimicrobial Resistance Monitoring System -...

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

    PubMed

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

    2016-08-01

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

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

    PubMed

    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.

  8. Acquired antimicrobial resistance in the intestinal microbiota of diverse cat populations.

    PubMed

    Moyaert, H; De Graef, E M; Haesebrouck, F; Decostere, A

    2006-08-01

    The aim of this study was to investigate the prevalence of acquired antimicrobial resistance in the resident intestinal microbiota of cats and to identify significant differences between various cat populations. Escherichia coli, Enterococcus faecalis, E. faecium and Streptococcus canis were isolated as faecal indicator bacteria from rectal swabs of 47 individually owned cats, 47 cattery cats and 18 hospitalised cats, and submitted through antimicrobial sensitivity tests. The results revealed that bacteria isolated from hospitalised and/or cattery cats were more frequently resistant than those from individually owned cats. E. coli isolates from hospitalised cats were particularly resistant to ampicillin, tetracycline and sulfonamide. Both enterococci and streptococci showed high resistance to tetracycline and in somewhat lesser extent to erythromycin and tylosin. Most E. faecium isolates were resistant to lincomycin and penicillin. One E. faecalis as well as one E. faecium isolate from hospitalised cats showed 'high-level resistance' (MIC > 500 microg/ml) against gentamicin, a commonly used antimicrobial agent in case of human enterococcal infections. The results of this research demonstrate that the extent of acquired antimicrobial resistance in the intestinal microbiota of cats depends on the social environment of the investigated population. It is obvious that the flora of healthy cats may act as a reservoir of resistance genes. PMID:16330058

  9. Antimicrobial resistance of Escherichia coli isolates from canine urinary tract infections.

    PubMed

    Chang, Shao-Kuang; Lo, Dan-Yuan; Wei, Hen-Wei; Kuo, Hung-Chih

    2015-01-01

    This study determined the antimicrobial resistance profiles of Escherichia coli isolates from dogs with a presumptive diagnosis of urinary tract infection (UTI). Urine samples from 201 dogs with UTI diagnosed through clinical examination and urinalysis were processed for isolation of Escherichia coli. Colonies from pure cultures were identified by biochemical reactions (n=114) and were tested for susceptibility to 18 antimicrobials. The two most frequent antimicrobials showing resistance in Urinary E. coli isolates were oxytetracycline and ampicillin. Among the resistant isolates, 17 resistance patterns were observed, with 12 patterns involving multidrug resistance (MDR). Of the 69 tetracycline-resistant E. coli isolates, tet(B) was the predominant resistance determinant and was detected in 50.9% of the isolates, whereas the remaining 25.5% isolates carried the tet(A) determinant. Most ampicillin and/or amoxicillin-resistant E. coli isolates carried blaTEM-1 genes. Class 1 integrons were prevalent (28.9%) and contained previously described gene cassettes that are implicated primarily in resistance to aminoglycosides and trimethoprim (dfrA1, dfrA17-aadA5). Of the 44 quinolone-resistant E. coli isolates, 38 were resistant to nalidixic acid, and 6 were resistant to nalidixic acid, ciprofloxacin and enrofloxacin. Chromosomal point mutations were found in the GyrA (Ser83Leu) and ParC (Ser80Ile) genes. Furthermore, the aminoglycoside resistance gene aacC2, the chloramphenicol resistant gene cmlA and the florfenicol resistant gene floR were also identified. This study revealed an alarming rate of antimicrobial resistance among E. coli isolates from dogs with UTIs. PMID:25720807

  10. Antimicrobial resistance of Escherichia coli isolates from canine urinary tract infections

    PubMed Central

    CHANG, Shao-Kuang; LO, Dan-Yuan; WEI, Hen-Wei; KUO, Hung-Chih

    2014-01-01

    This study determined the antimicrobial resistance profiles of Escherichia coli isolates from dogs with a presumptive diagnosis of urinary tract infection (UTI). Urine samples from 201 dogs with UTI diagnosed through clinical examination and urinalysis were processed for isolation of Escherichia coli. Colonies from pure cultures were identified by biochemical reactions (n=114) and were tested for susceptibility to 18 antimicrobials. The two most frequent antimicrobials showing resistance in Urinary E. coli isolates were oxytetracycline and ampicillin. Among the resistant isolates, 17 resistance patterns were observed, with 12 patterns involving multidrug resistance (MDR). Of the 69 tetracycline-resistant E. coli isolates, tet(B) was the predominant resistance determinant and was detected in 50.9% of the isolates, whereas the remaining 25.5% isolates carried the tet(A) determinant. Most ampicillin and/or amoxicillin-resistant E. coli isolates carried blaTEM-1 genes. Class 1 integrons were prevalent (28.9%) and contained previously described gene cassettes that are implicated primarily in resistance to aminoglycosides and trimethoprim (dfrA1, dfrA17-aadA5). Of the 44 quinolone-resistant E. coli isolates, 38 were resistant to nalidixic acid, and 6 were resistant to nalidixic acid, ciprofloxacin and enrofloxacin. Chromosomal point mutations were found in the GyrA (Ser83Leu) and ParC (Ser80Ile) genes. Furthermore, the aminoglycoside resistance gene aacC2, the chloramphenicol resistant gene cmlA and the florfenicol resistant gene floR were also identified. This study revealed an alarming rate of antimicrobial resistance among E. coli isolates from dogs with UTIs. PMID:25720807

  11. Surveillance of antimicrobial resistance in Lebanese hospitals: retrospective nationwide compiled data.

    PubMed

    Chamoun, Kamal; Farah, Maya; Araj, Georges; Daoud, Ziad; Moghnieh, Rima; Salameh, Pascale; Saade, Danielle; Mokhbat, Jacques; Abboud, Emme; Hamze, Monzer; Abboud, Edmond; Jisr, Tamima; Haddad, Antoine; Feghali, Rita; Azar, Nadim; El-Zaatari, Mohammad; Chedid, Marwan; Haddad, Christian; Zouain Dib Nehme, Mireille; Barakat, Angelique; Husni, Rola

    2016-05-01

    Antimicrobial resistance is closely linked to antimicrobial use and is a growing concern worldwide. Antimicrobial resistance increases healthcare costs substantially in many countries, including Lebanon. National data from Lebanon have, in the most part, been limited to a few academic hospitals. The Lebanese Society of Infectious Diseases conducted a retrospective study to better describe the antimicrobial susceptibility patterns of bacterial isolates in Lebanon. Data were based on records retrieved from the bacteriology laboratories of 16 different Lebanese hospitals between January 2011 and December 2013. The susceptibility results of a total 20684 Gram-positive and 55594 Gram-negative bacteria were analyzed. The prevalence rate of methicillin-resistant Staphylococcus aureus was 27.6% and of vancomycin-resistant Enterococcus spp was 1%. Streptococcus pneumoniae had susceptibilities of 46% to oxacillin, 63% to erythromycin, and 98% to levofloxacin. Streptococcus pyogenes had susceptibilities of 94% to erythromycin and 95% to clindamycin. The mean ampicillin susceptibility of Haemophilus influenzae, Salmonella spp, and Shigella spp isolates was 79%, 81.3%, and 62.2%, respectively. The extended-spectrum beta-lactamase production rate for Escherichia coli was 32.3% and for Klebsiella spp was 29.2%. Acinetobacter spp showed high resistance to most antimicrobials, with low resistance to colistin (17.1%). Pseudomonas spp susceptibilities to piperacillin-tazobactam and imipenem were lower than 80% (79.7% and 72.8%, respectively). This study provides population-specific data that are valuable in guiding antimicrobial use in Lebanon and neighbouring countries and will help in the establishment of a surveillance system for antimicrobial resistance following the implementation of a nationwide standardization of laboratory methods and data entry. PMID:26996458

  12. Surveillance of antimicrobial resistance in Lebanese hospitals: retrospective nationwide compiled data.

    PubMed

    Chamoun, Kamal; Farah, Maya; Araj, Georges; Daoud, Ziad; Moghnieh, Rima; Salameh, Pascale; Saade, Danielle; Mokhbat, Jacques; Abboud, Emme; Hamze, Monzer; Abboud, Edmond; Jisr, Tamima; Haddad, Antoine; Feghali, Rita; Azar, Nadim; El-Zaatari, Mohammad; Chedid, Marwan; Haddad, Christian; Zouain Dib Nehme, Mireille; Barakat, Angelique; Husni, Rola

    2016-05-01

    Antimicrobial resistance is closely linked to antimicrobial use and is a growing concern worldwide. Antimicrobial resistance increases healthcare costs substantially in many countries, including Lebanon. National data from Lebanon have, in the most part, been limited to a few academic hospitals. The Lebanese Society of Infectious Diseases conducted a retrospective study to better describe the antimicrobial susceptibility patterns of bacterial isolates in Lebanon. Data were based on records retrieved from the bacteriology laboratories of 16 different Lebanese hospitals between January 2011 and December 2013. The susceptibility results of a total 20684 Gram-positive and 55594 Gram-negative bacteria were analyzed. The prevalence rate of methicillin-resistant Staphylococcus aureus was 27.6% and of vancomycin-resistant Enterococcus spp was 1%. Streptococcus pneumoniae had susceptibilities of 46% to oxacillin, 63% to erythromycin, and 98% to levofloxacin. Streptococcus pyogenes had susceptibilities of 94% to erythromycin and 95% to clindamycin. The mean ampicillin susceptibility of Haemophilus influenzae, Salmonella spp, and Shigella spp isolates was 79%, 81.3%, and 62.2%, respectively. The extended-spectrum beta-lactamase production rate for Escherichia coli was 32.3% and for Klebsiella spp was 29.2%. Acinetobacter spp showed high resistance to most antimicrobials, with low resistance to colistin (17.1%). Pseudomonas spp susceptibilities to piperacillin-tazobactam and imipenem were lower than 80% (79.7% and 72.8%, respectively). This study provides population-specific data that are valuable in guiding antimicrobial use in Lebanon and neighbouring countries and will help in the establishment of a surveillance system for antimicrobial resistance following the implementation of a nationwide standardization of laboratory methods and data entry.

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

    PubMed

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

    2016-01-01

    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.

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

    PubMed Central

    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

  15. Evaluation of antimicrobial resistance profiles of escherichia coli isolates of broiler chickens at slaughter in Alberta, Canada.

    PubMed

    Mainali, Chunu; McFall, Margaret; King, Robin; Irwin, Rebecca

    2013-12-01

    This study was conducted to investigate antimicrobial resistance profiles of Escherichia coli isolates from broiler chickens in Alberta, Canada. Cecal contents of broiler chickens from 24 flocks were collected at slaughter between January and March 2005 for culture and antimicrobial susceptibility testing against a panel of 15 antimicrobials using a broth microdilution technique. Of 600 E. coli isolates tested, 475 (79.2%) were resistant to one or more antimicrobials, 326 (54.3%) were resistant to three or more antimicrobials, 65 (10.8%) were resistant to five or more antimicrobials, and 15 (2.5%) were resistant to seven or more antimicrobials. The most common resistance was to tetracycline (69.2%), followed by streptomycin (48.2%), kanamycin (40.3%), and sulfisoxazole (38.0%). None of the E. coli isolates were resistant to amikacin, ceftriaxone, or ciprofloxacin. Of the isolates that were resistant to two or more antimicrobials, the most common multidrug resistance patterns were streptomycinte-tracycline (44.0%), streptomycin-sulfisoxazole-tetracycline (30.7%), and kanamycin-streptomycin-sulfisoxazole-tetracycline (23.5%). Resistance to tetracycline and kanamycin (odds ratio = 46.7, P = 0.0001) was highly associated, followed by resistance to streptomycin and sulfisoxazole (odds ratio = 12.0, P = 0.0001), and streptomycin and tetracycline (odds ratio = 10.3, P = 0.0001). The flock level prevalence of resistance varied from 16.7% for chloramphenicol to 100.0% for ampicillin, streptomycin, sulfisoxazole, and tetracycline. The results of this study provided baseline information on antimicrobial susceptibility of E. coli isolates of broiler chickens at slaughter in Alberta, which can serve as a bench mark for future research.

  16. Increased survival of experimentally evolved antimicrobial peptide-resistant Staphylococcus aureus in an animal host.

    PubMed

    Dobson, Adam J; Purves, Joanne; Rolff, Jens

    2014-09-01

    Antimicrobial peptides (AMPs) have been proposed as new class of antimicrobial drugs, following the increasing prevalence of bacteria resistant to antibiotics. Synthetic AMPs are functional analogues of highly evolutionarily conserved immune effectors in animals and plants, produced in response to microbial infection. Therefore, the proposed therapeutic use of AMPs bears the risk of 'arming the enemy': bacteria that evolve resistance to AMPs may be cross-resistant to immune effectors (AMPs) in their hosts. We used a panel of populations of Staphylococcus aureus that were experimentally selected for resistance to a suite of individual AMPs and antibiotics to investigate the 'arming the enemy' hypothesis. We tested whether the selected strains showed higher survival in an insect model (Tenebrio molitor) and cross-resistance against other antimicrobials in vitro. A population selected for resistance to the antimicrobial peptide iseganan showed increased in vivo survival, but was not more virulent. We suggest that increased survival of AMP-resistant bacteria almost certainly poses problems to immune-compromised hosts.

  17. Antimicrobial Resistance and Virulence: a Successful or Deleterious Association in the Bacterial World?

    PubMed Central

    Beceiro, Alejandro; Tomás, María

    2013-01-01

    SUMMARY Hosts and bacteria have coevolved over millions of years, during which pathogenic bacteria have modified their virulence mechanisms to adapt to host defense systems. Although the spread of pathogens has been hindered by the discovery and widespread use of antimicrobial agents, antimicrobial resistance has increased globally. The emergence of resistant bacteria has accelerated in recent years, mainly as a result of increased selective pressure. However, although antimicrobial resistance and bacterial virulence have developed on different timescales, they share some common characteristics. This review considers how bacterial virulence and fitness are affected by antibiotic resistance and also how the relationship between virulence and resistance is affected by different genetic mechanisms (e.g., coselection and compensatory mutations) and by the most prevalent global responses. The interplay between these factors and the associated biological costs depend on four main factors: the bacterial species involved, virulence and resistance mechanisms, the ecological niche, and the host. The development of new strategies involving new antimicrobials or nonantimicrobial compounds and of novel diagnostic methods that focus on high-risk clones and rapid tests to detect virulence markers may help to resolve the increasing problem of the association between virulence and resistance, which is becoming more beneficial for pathogenic bacteria. PMID:23554414

  18. Increased survival of experimentally evolved antimicrobial peptide-resistant Staphylococcus aureus in an animal host.

    PubMed

    Dobson, Adam J; Purves, Joanne; Rolff, Jens

    2014-09-01

    Antimicrobial peptides (AMPs) have been proposed as new class of antimicrobial drugs, following the increasing prevalence of bacteria resistant to antibiotics. Synthetic AMPs are functional analogues of highly evolutionarily conserved immune effectors in animals and plants, produced in response to microbial infection. Therefore, the proposed therapeutic use of AMPs bears the risk of 'arming the enemy': bacteria that evolve resistance to AMPs may be cross-resistant to immune effectors (AMPs) in their hosts. We used a panel of populations of Staphylococcus aureus that were experimentally selected for resistance to a suite of individual AMPs and antibiotics to investigate the 'arming the enemy' hypothesis. We tested whether the selected strains showed higher survival in an insect model (Tenebrio molitor) and cross-resistance against other antimicrobials in vitro. A population selected for resistance to the antimicrobial peptide iseganan showed increased in vivo survival, but was not more virulent. We suggest that increased survival of AMP-resistant bacteria almost certainly poses problems to immune-compromised hosts. PMID:25469169

  19. Antimicrobial resistance profiles in pathogens isolated from chickens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 (...

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

    PubMed

    Gomba, Annancietar; Chidamba, Lizyben; Korsten, Lise

    2016-09-01

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

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

    PubMed

    Gomba, Annancietar; Chidamba, Lizyben; Korsten, Lise

    2016-09-01

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

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

    PubMed

    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.

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

    PubMed

    Roca, I; Akova, M; Baquero, F; Carlet, J; Cavaleri, M; Coenen, S; Cohen, J; Findlay, D; Gyssens, I; Heuer, O E; Kahlmeter, G; Kruse, H; Laxminarayan, R; Liébana, E; López-Cerero, L; MacGowan, A; Martins, M; Rodríguez-Baño, J; Rolain, J-M; Segovia, C; Sigauque, B; Tacconelli, E; Wellington, E; Vila, J

    2015-07-01

    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.

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

    PubMed

    Roca, I; Akova, M; Baquero, F; Carlet, J; Cavaleri, M; Coenen, S; Cohen, J; Findlay, D; Gyssens, I; Heuer, O E; Kahlmeter, G; Kruse, H; Laxminarayan, R; Liébana, E; López-Cerero, L; MacGowan, A; Martins, M; Rodríguez-Baño, J; Rolain, J-M; Segovia, C; Sigauque, B; Tacconelli, E; Wellington, E; Vila, J

    2015-07-01

    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. PMID:26029375

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

    PubMed

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

    2016-02-01

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

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

    PubMed

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

    2015-10-01

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

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

    PubMed

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

    2015-10-01

    The emergence of livestock-associated methicillin-resistant Staphylococcus aureus (MRSA) in food-producing animals is of increasing interest, raising questions about the presence of MRSA in food of animal origin and potential sources of transmission to humans via the food chain. In this study, the prevalence, molecular characterization, virulence factors, and antimicrobial susceptibility patterns of MRSA isolates from 200 retail raw chicken samples in Egypt were determined. MRSA was detected by positive amplification of the mecA gene in 38% (76 of 200) of chicken samples analyzed. This represents a potential public health threat in Egypt, as this contamination rate seems to be the highest among other studies reported worldwide. Furthermore, genes encoding α-hemolysin (hla) and staphylococcal enterotoxins (sea, seb, and sec) were detected in all of the 288 MRSA isolates. Nonetheless, none of the strains tested carried tst, the gene encoding toxic shock syndrome toxin 1. Antimicrobial resistance of MRSA isolates was most frequently detected against penicillin (93.4%), ampicillin (88.9%), and cloxacillin (83.3%). These results suggest that retail chicken might be a significant potential source for transmission of multidrug-resistant and toxigenic S. aureus in Egypt. This underlines the need for stricter hygienic measures in chicken production in Egypt to minimize the risk of transmission of these strains to consumers. To the best of our knowledge, this is the first study that reports the isolation and molecular characterization of MRSA in retail chicken samples in Egypt. PMID:26408138

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

    PubMed

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

    2014-10-01

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

  9. Antimicrobial resistance trends among canine Escherichia coli isolates obtained from clinical samples in the northeastern USA, 2004-2011.

    PubMed

    Cummings, Kevin J; Aprea, Victor A; Altier, Craig

    2015-04-01

    Our objectives were to describe the antimicrobial susceptibility of Escherichia coli isolates from dogs in the northeastern USA and to identify temporal trends in resistance to selected antimicrobial agents. Data were collected retrospectively for all canine E. coli isolates from clinical samples submitted to Cornell University's Animal Health Diagnostic Center between January 1, 2004 and December 31, 2011. Antimicrobial susceptibility testing was performed on 3519 canine E. coli isolates; frequency of resistance to each agent ranged from 0.4% (amikacin) to 34.3% (ampicillin). No trends were evident among urinary isolates, but cephalosporin resistance remained consistently high. Among non-urinary isolates, there was evidence of a significantly increasing trend in prevalence of resistance to several agents, including cephalosporins, enrofloxacin, and tetracycline. These data suggest that some of the most commonly used antimicrobial agents in companion animal practice are becoming less effective against canine E. coli infections outside the urinary tract.

  10. Analysis of antimicrobial resistance mechanisms in MDR bacteria by microarray and high-throughput sequencing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antimicrobial resistance in pathogenic bacteria is a major concern in human and animal health. The National Antimicrobial Resistance Monitoring System (NARMS) was designed by the CDC, FDA, and USDA to monitor antimicrobial resistance in the U.S. The Bacterial Epidemiology and Antimicrobial Resistanc...

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

    PubMed

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

    2016-01-01

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

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

    PubMed

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

    2016-01-01

    A majority of antibiotic-resistant bacterial infections in the United States are associated with biofilms. Nanoscale biophysical measures are increasingly revealing that adhesive and viscoelastic properties of bacteria play essential roles across multiple stages of biofilm development. Atomic Force Microscopy (AFM) applied to strains with variation in antimicrobial resistance enables new opportunities for investigating the function of adhesive forces (stickiness) in biofilm formation. AFM force spectroscopy analysis of a field strain of Listeria innocua and the strain Escherichia coli K-12 MG1655 revealed differing adhesive forces between antimicrobial resistant and nonresistant strains. Significant increases in stickiness were found at the nanonewton level for strains of Listeria innocua and Escherichia coli in association with benzalkonium chloride and silver nanoparticle resistance respectively. This advancement in the usage of AFM provides for a fast and reliable avenue for analyzing antimicrobial resistant cells and the molecular dynamics of biofilm formation as a protective mechanism. PMID:26914334

  13. Mechanobiology of Antimicrobial Resistant Escherichia coli and Listeria innocua

    PubMed Central

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

    2016-01-01

    A majority of antibiotic-resistant bacterial infections in the United States are associated with biofilms. Nanoscale biophysical measures are increasingly revealing that adhesive and viscoelastic properties of bacteria play essential roles across multiple stages of biofilm development. Atomic Force Microscopy (AFM) applied to strains with variation in antimicrobial resistance enables new opportunities for investigating the function of adhesive forces (stickiness) in biofilm formation. AFM force spectroscopy analysis of a field strain of Listeria innocua and the strain Escherichia coli K-12 MG1655 revealed differing adhesive forces between antimicrobial resistant and nonresistant strains. Significant increases in stickiness were found at the nanonewton level for strains of Listeria innocua and Escherichia coli in association with benzalkonium chloride and silver nanoparticle resistance respectively. This advancement in the usage of AFM provides for a fast and reliable avenue for analyzing antimicrobial resistant cells and the molecular dynamics of biofilm formation as a protective mechanism. PMID:26914334

  14. A new strategy to fight antimicrobial resistance: the revival of old antibiotics

    PubMed Central

    Cassir, Nadim; Rolain, Jean-Marc; Brouqui, Philippe

    2014-01-01

    The increasing prevalence of hospital and community-acquired infections caused by multidrug-resistant (MDR) bacterial pathogens is limiting the options for effective antibiotic therapy. Moreover, this alarming spread of antimicrobial resistance has not been paralleled by the development of novel antimicrobials. Resistance to the scarce new antibiotics is also emerging. In this context, the rational use of older antibiotics could represent an alternative to the treatment of MDR bacterial pathogens. It would help to optimize the armamentarium of antibiotics in the way to preserve new antibiotics and avoid the prescription of molecules known to favor the spread of resistance (i.e., quinolones). Furthermore, in a global economical perspective, this could represent a useful public health orientation knowing that several of these cheapest “forgotten” antibiotics are not available in many countries. We will review here the successful treatment of MDR bacterial infections with the use of old antibiotics and discuss their place in current practice. PMID:25368610

  15. Antimicrobial Resistance Profiles in Escherichia coli O157 Isolates from Northern Colorado Dairies.

    PubMed

    McConnel, Craig S; Stenkamp-Strahm, Chloe M; Rao, Sangeeta; Linke, Lyndsey M; Magnuson, Roberta J; Hyatt, Doreene R

    2016-03-01

    Escherichia coli O157 (EcO157) infections can lead to serious disease and death in humans. Although the ecology of EcO157 is complex, ruminant animals serve as an important reservoir for human infection. Dairy cattle are unique because they may be a source of contamination for milk, meat, and manure-fertilized crops. Foodborne dairy pathogens such as EcO157 are of primary importance to public health. Antimicrobial resistance (AMR) is a complex phenomenon that complicates the treatment of serious bacterial infections and is of increasing concern. In the face of recommended use restrictions for antimicrobial agents in livestock operations, current AMR patterns in known foodborne pathogens should be documented. The objective of this study was to document AMR patterns in EcO157 isolates from dairies in northern Colorado using antimicrobial agents commonly found on dairies and representative of medically important antimicrobial drug classes. Seventy-five EcO157 isolates were recovered from three dairies. Six isolates were resistant to at least 1 of the 10 tested antimicrobial agents: four were resistant to streptomycin, sulfisoxazole, and tetracycline; one was resistant to streptomycin and tetracycline; and one was resistant to only tetracycline. All resistant isolates were from a single dairy. Overall, a low prevalence (8%) of AMR was observed among the 75 EcO157 isolates. No significant effects on AMR profiles due to virulence genes, parity, or previous antimicrobial treatments within the current lactation period were detected. The results of this study provide background information for future comparative studies investigating AMR trends. Future studies should include more participating farms and more samples and should control for potential confounding factors of AMR that may underlie individual farm variation. PMID:26939660

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

    PubMed

    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.

  17. Antimicrobial susceptibility testing for Helicobacter pylori in times of increasing antibiotic resistance.

    PubMed

    Smith, Sinéad M; O'Morain, Colm; McNamara, Deirdre

    2014-08-01

    The gram-negative bacterium Helicobacter pylori (H. pylori) causes chronic gastritis, gastric and duodenal ulcers, gastric cancer and mucosa-associated lymphoid tissue lymphoma. Treatment is recommended in all symptomatic patients. The current treatment options for H. pylori infection are outlined in this review in light of the recent challenges in eradication success, largely due to the rapid emergence of antibiotic resistant strains of H. pylori. Antibiotic resistance is a constantly evolving process and numerous studies have shown that the prevalence of H. pylori antibiotic resistance varies significantly from country to country, and even between regions within the same country. In addition, recent data has shown that previous antibiotic use is associated with harbouring antibiotic resistant H. pylori. Local surveillance of antibiotic resistance is warranted to guide clinicians in their choice of therapy. Antimicrobial resistance is assessed by H. pylori culture and antimicrobial susceptibility testing. Recently developed molecular tests offer an attractive alternative to culture and allow for the rapid molecular genetic identification of H. pylori and resistance-associated mutations directly from biopsy samples or bacterial culture material. Accumulating evidence indicates that surveillance of antimicrobial resistance by susceptibility testing is feasible and necessary to inform clinicians in their choice of therapy for management of H. pylori infection.

  18. Antimicrobial susceptibility testing for Helicobacter pylori in times of increasing antibiotic resistance

    PubMed Central

    Smith, Sinéad M; O’Morain, Colm; McNamara, Deirdre

    2014-01-01

    The gram-negative bacterium Helicobacter pylori (H. pylori) causes chronic gastritis, gastric and duodenal ulcers, gastric cancer and mucosa-associated lymphoid tissue lymphoma. Treatment is recommended in all symptomatic patients. The current treatment options for H. pylori infection are outlined in this review in light of the recent challenges in eradication success, largely due to the rapid emergence of antibiotic resistant strains of H. pylori. Antibiotic resistance is a constantly evolving process and numerous studies have shown that the prevalence of H. pylori antibiotic resistance varies significantly from country to country, and even between regions within the same country. In addition, recent data has shown that previous antibiotic use is associated with harbouring antibiotic resistant H. pylori. Local surveillance of antibiotic resistance is warranted to guide clinicians in their choice of therapy. Antimicrobial resistance is assessed by H. pylori culture and antimicrobial susceptibility testing. Recently developed molecular tests offer an attractive alternative to culture and allow for the rapid molecular genetic identification of H. pylori and resistance-associated mutations directly from biopsy samples or bacterial culture material. Accumulating evidence indicates that surveillance of antimicrobial resistance by susceptibility testing is feasible and necessary to inform clinicians in their choice of therapy for management of H. pylori infection. PMID:25110421

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

    PubMed

    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.

  20. Antimicrobial resistance and population structure of Staphylococcus epidermidis recovered from pig farms in Belgium.

    PubMed

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

    2015-03-01

    Pigs are known to harbour a variety of staphylococcal bacteria, including Staphylococcus epidermidis, in the upper respiratory tract. The aim of the present study was to determine the prevalence, genetic diversity, virulence and antimicrobial resistance of S. epidermidis in healthy pigs, as well as to identify the potential role of pigs as a reservoir of zoonotic infection. The overall prevalence of S. epidermidis carriage was 28%, with approximately half of the pigs tested (13.5%) carrying methicillin-resistant S. epidermidis (MRSE). Some isolates belonged to multilocus sequence types, associated with healthy human carriers or healthcare personnel (ST88, ST210) whereas others were related to animal or environmental strains (ST100, ST273). Most MRSE isolates carried SCCmec type IV, with SCCmec type V or a non-typeable SCCmec detected in the remaining isolates. Both MRSE and methicillin-susceptible S. epidermidis isolates showed a degree of antimicrobial resistance, with most resistant to tetracycline and/or trimethoprim antimicrobial drugs. Isolates subjected to micro-array analysis carried the antimicrobial resistance genes tet(K), tet(M) and dfrS1, while half carried the arginine catabolic element (ACME) associated with colonisation. Some MRSE ST273 strains also carried the ica operon involved in biofilm formation. These research findings provide insight into the population structure and characteristics of S. epidermidis carried by healthy pigs, suggesting a role for these strains as a potential reservoir for antimicrobial and virulence genes and indicating that exchange of strains might occur between pigs and humans.

  1. Multiple Antimicrobial Resistance in Plague: An Emerging Public Health Risk

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antimicrobial resistance in Yersinia pestis is rare, yet constitutes a significant international public health and biodefense threat. In 1995, the first multidrug resistant (MDR) isolate of Y. pestis (strain IP275) was identified, and shown to contain a self-transmissible plasmid (pIP1202) that con...

  2. Are the public getting the message about antimicrobial resistance?

    PubMed

    Shallcross, Laura J; Berin, Michelle; Roe, Jennifer; Noursadeghi, Mahdad

    2015-01-01

    Raising public awareness of the need to use antibiotics appropriately is a major focus of the UK Government's strategy to tackle antimicrobial resistance. To investigate the public's views on antibiotic use and resistance we conducted a survey of 120 people as part of patient engagement activities held at University College London Hospital in June 2015. PMID:26566441

  3. Are the public getting the message about antimicrobial resistance?

    PubMed

    Shallcross, Laura J; Berin, Michelle; Roe, Jennifer; Noursadeghi, Mahdad

    2015-01-01

    Raising public awareness of the need to use antibiotics appropriately is a major focus of the UK Government's strategy to tackle antimicrobial resistance. To investigate the public's views on antibiotic use and resistance we conducted a survey of 120 people as part of patient engagement activities held at University College London Hospital in June 2015.

  4. Antimicrobial Resistance in Salmonella Isolates Recovered from Slaughter Cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    *Background*: Antimicrobial resistance is of global concern and first emerged in bacteria shortly after the introduction of penicillin. It is common to see resistance develop after new compounds (regardless of class) are released. However many factors influence the persistence and transmission of r...

  5. Factors affecting the reversal of antimicrobial-drug resistance.

    PubMed

    Johnsen, Pål J; Townsend, Jeffrey P; Bøhn, Thomas; Simonsen, Gunnar S; Sundsfjord, Arnfinn; Nielsen, Kaare M

    2009-06-01

    The persistence or loss of acquired antimicrobial-drug resistance in bacterial populations previously exposed to drug-selective pressure depends on several biological processes. We review mechanisms promoting or preventing the loss of resistance, including rates of reacquisition, effects of resistance traits on bacterial fitness, linked selection, and segregational stability of resistance determinants. As a case study, we discuss the persistence of glycopeptide-resistant enterococci in Norwegian and Danish poultry farms 12 years after the ban of the animal growth promoter avoparcin. We conclude that complete eradication of antimicrobial resistance in bacterial populations following relaxed drug-selective pressures is not straightforward. Resistance determinants may persist at low, but detectable, levels for many years in the absence of the corresponding drugs. PMID:19467475

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

    PubMed Central

    Lysnyansky, Inna; Ayling, Roger D.

    2016-01-01

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

  7. Antimicrobial resistance and molecular epidemiology of vancomycin-resistant enterococci from North America and Europe: a report from the SENTRY antimicrobial surveillance program.

    PubMed

    Deshpande, Lalitagauri M; Fritsche, Thomas R; Moet, Gary J; Biedenbach, Douglas J; Jones, Ronald N

    2007-06-01

    Increases in prevalence of vancomycin-resistant enterococci (VRE) have been documented globally since its emergence in the 1980s. A SENTRY Antimicrobial Surveillance Program (2003) objective monitored VRE isolates with respect to antimicrobial susceptibility trends, geographic resistance variability, and clonal dissemination. In 2003, VRE isolates from North America (United States and Canada, n = 839, 26 sites) and Europe (n = 56, 10 sites) were susceptibility tested using Clinical and Laboratory Standards Institute (CLSI) reference methodologies. Based on resistance profiles, 155 isolates displayed similar multidrug-resistant (MDR) profiles and were temporally related; these were subsequently submitted for typing by pulsed-field gel electrophoresis (PFGE). Most of the submitted isolates were Enterococcus faecium (91.0%) and Enterococcus faecalis (7.8%). Among VRE, the VanA phenotype was more prevalent in North America (76%) than Europe (40%), and all isolates had elevated resistance rates to other antimicrobial classes including the following: 1) chloramphenicol resistance among E. faecalis being greater in North America than in Europe (28.6% versus 7.1%, respectively) but reversed among E. faecium (0.5% and 15.0%, the latter due to clonal occurrences); 2) ciprofloxacin resistance in North America >99% for both species and in Europe varying from 85.7% to 87.5%; 3) rare occurrences of linezolid resistance in North America (0.8% to 1.8%) due to G2576U ribosomal mutation; 4) higher quinupristin/dalfopristin resistance observed among European E. faecium strains (10.0% versus 0.6%); and 5) higher rifampin resistance rates among European E. faecalis (21.4% versus 5.4%). Thirty-five MDR epidemic clusters were identified by PFGE in 21 North American and 2 European medical centers including the following: 1) VanA (20 sites, 27 clonal occurrences) and VanB (1 site, 2 clonal occurrences); 2) elevated quinupristin/dalfopristin MIC results (not vatD/E, 3 sites); and 3

  8. Race Against Antimicrobial Resistance Requires Coordinated Action – An Overview

    PubMed Central

    Premanandh, J.; Samara, B. S.; Mazen, A. N.

    2016-01-01

    Resistance developed by microbes is challenging success stories of treatment of infectious diseases with anti-microbials. Developing new antimicrobials against these resistant organisms does not progress at the same speed. In an effort to address this key issue, this work overviews the role of different stakeholders and discusses preventative and control measures for effective management of available resources. Roles and concerns of physicians, pharmacists and the public are also discussed. More than anything, this situation requires immediate action to establish antimicrobial stewardship program, control over the counter sale and promote public awareness. The paper also confronts the idea of curbing the use of antimicrobials using mass media, while detailing the consequences of non-therapeutic use. The role of policy makers in taking global action is essential to establishing authority or agency for formulating national guidelines and regulations for prudently using antimicrobials. To do this, this paper recommend the establishment of a global fund. In conclusion, the race against resistance is a collective responsibility requiring coordinated action at local, national, regional and international levels to ensure sustained utilization of antimicrobials. PMID:26869998

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

    PubMed Central

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

    2016-01-01

    The presence of antimicrobial resistance and virulence factors of 174 Escherichia coli strains isolated from healthy Portuguese Gallus gallus was evaluated. Resistance profiles were determined against 33 antimicrobials by microbroth dilution. Resistance was prevalent for tetracycline (70%) and ampicillin (63%). Extended-spectrum beta-lactamase (ESBL) phenotype was observed in 18% of the isolates. Multidrug resistance was found in 56% of isolates. A subset of 74 isolates were screened by DNA 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. PMID:27025519

  10. The Risk of Some Veterinary Antimicrobial Agents on Public Health Associated with Antimicrobial Resistance and their Molecular Basis

    PubMed Central

    Hao, Haihong; Sander, Pascal; Iqbal, Zahid; Wang, Yulian; Cheng, Guyue; Yuan, Zonghui

    2016-01-01

    The risk of antimicrobial agents used in food-producing animals on public health associated with antimicrobial resistance continues to be a current topic of discussion as related to animal and human public health. In the present review, resistance monitoring data, and risk assessment results of some important antimicrobial agents were cited to elucidate the possible association of antimicrobial use in food animals and antimicrobial resistance in humans. From the selected examples, it was apparent from reviewing the published scientific literature that the ban on use of some antimicrobial agents (e.g., avoparcin, fluoroquinolone, tetracyclines) did not change drug resistance patterns and did not mitigate the intended goal of minimizing antimicrobial resistance. The use of some antimicrobial agents (e.g., virginiamycin, macrolides, and cephalosporins) in food animals may have an impact on the antimicrobial resistance in humans, but it was largely depended on the pattern of drug usage in different geographical regions. The epidemiological characteristics of resistant bacteria were closely related to molecular mechanisms involved in the development, fitness, and transmission of antimicrobial resistance. PMID:27803693

  11. Antimicrobial resistance: moving from professional engagement to public action.

    PubMed

    Ashiru-Oredope, D; Hopkins, S

    2015-11-01

    Antimicrobial-resistant infections claim ≥700 000 lives each year globally. It is therefore important that both healthcare professionals and the public know the threat antimicrobial resistance poses and the individual actions they can take to combat antimicrobial resistance. Antibiotic awareness campaigns in England using posters or leaflets have had little or no impact on knowledge, behaviour or prescription rates. Centrally coordinated, multimodal campaigns in two European countries (ongoing for several years and including print and mass media, web site and guidelines, as well as academic detailing and individual feedback to prescribers) have led to reductions in antibiotic use. To change behaviour and reduce antibiotic use in England, a coordinated and comprehensive interdisciplinary and multifaceted (multimodal) approach using behavioural science and targeted at specific groups (both professional and public) is required. Such campaigns should have an integrated evaluation plan using a combination of formative, process and summative measures from the outset to completion of a campaign. PMID:26377862

  12. Extended antimicrobial resistance screening of the dominant faecal Escherichia coli and of rare resistant clones.

    PubMed

    Kronvall, Göran; Larsson, Mattias; Borén, Charlotte; Kahlmeter, Gunnar; Bartoloni, Alessandro; Rossolini, Gian Maria; Grape, Malin; Kristiansson, Charlotte; Karlsson, Inga

    2005-12-01

    Fifty faecal samples from healthy adults were grown on MacConkey agar and three pink colonies were subcultured, identified to species level and their antimicrobial susceptibility determined. Forty-seven samples yielded 141 isolates of Escherichia coli that were susceptible to most antimicrobials. Resistance was noted for ampicillin (30.5%), chloramphenicol (12.1%), tetracycline (23.4%), trimethoprim (24.8%) and co-trimoxazole (22.7%). A direct faecal plating method was used for extended resistance screening with E. coli as the indicator organism. Zone breakpoints were determined using normalised resistance interpretation and gave similar susceptibility results. Eighty-eight isolates of E. coli from within the zones of inhibition revealed four times more antimicrobial resistance. Extended antimicrobial resistance screening both provides the susceptibility profile of the dominant E. coli isolate and detects greater resistance in rare isolates.

  13. Public health measures to control the spread of antimicrobial resistance in Neisseria gonorrhoeae in men who have sex with men.

    PubMed

    Xiridou, M; Soetens, L C; Koedijk, F D H; VAN DER Sande, M A B; Wallinga, J

    2015-06-01

    Gonorrhoea is one of the most common sexually transmitted infections. The control of gonorrhoea is extremely challenging because of the repeated development of resistance to the antibiotics used for its treatment. We explored different strategies to control the spread of antimicrobial resistance and prevent increases in gonorrhoea prevalence. We used a mathematical model that describes gonorrhoea transmission among men who have sex with men and distinguishes gonorrhoea strains sensitive or resistant to three antibiotics. We investigated the impact of combination therapy, switching first-line antibiotics according to resistance thresholds, and other control efforts (reduced sexual risk behaviour, increased treatment rate). Combination therapy can delay the spread of resistance better than using the 5% resistance threshold. Increased treatment rates, expected to enhance gonorrhoea control, may reduce gonorrhoea prevalence only in the short term, but could lead to more resistance and higher prevalence in the long term. Re-treatment of resistant cases with alternative antibiotics can substantially delay the spread of resistance. In conclusion, combination therapy and re-treatment of resistant cases with alternative antibiotics could be the most effective strategies to prevent increases in gonorrhoea prevalence due to antimicrobial resistance.

  14. Will new antimicrobials overcome resistance among Gram-negatives?

    PubMed

    Bassetti, Matteo; Ginocchio, Francesca; Mikulska, Małgorzata; Taramasso, Lucia; Giacobbe, Daniele Roberto

    2011-10-01

    The spread of resistance among Gram-positive and Gram-negative bacteria represents a growing challenge for the development of new antimicrobials. The pace of antibiotic drug development has slowed during the last decade and, especially for Gram-negatives, clinicians are facing a dramatic shortage in the availability of therapeutic options to face the emergency of the resistance problem throughout the world. In this alarming scenario, although there is a shortage of compounds reaching the market in the near future, antibiotic discovery remains one of the keys to successfully stem and maybe overcome the tide of resistance. Analogs of already known compounds and new agents belonging to completely new classes of antimicrobials are in early stages of development. Novel and promising anti-Gram-negative antimicrobials belong both to old (cephalosporins, carbapenems, β-lactamase inhibitors, monobactams, aminoglycosides, polymyxin analogues and tetracycline) and completely new antibacterial classes (boron-containing antibacterial protein synthesis inhibitors, bis-indoles, outer membrane synthesis inhibitors, antibiotics targeting novel sites of the 50S ribosomal subunit and antimicrobial peptides). However, all of these compounds are still far from being introduced into clinical practice. Therefore, infection control policies and optimization in the use of already existing molecules are still the most effective approaches to reduce the spread of resistance and preserve the activity of antimicrobials.

  15. Relationship of Antimicrobial Control Policies and Hospital and Infection Control Characteristics to Antimicrobial Resistance Rates

    PubMed Central

    Larson, Elaine L.; Quiros, Dave; Giblin, Tara; Lin, Susan

    2007-01-01

    Background Antibiotic misuse and noncompliance with infection control precautions have contributed to increasing levels of antimicrobial resistance in hospitals. Objectives To assess the extent to which resistance is monitored in infection control programs and to correlate resistance rates with characteristics of antimicrobial control policies, provider attitudes and practices, and systems-level indicators of implementation of the hand hygiene guideline of the Centers for Disease Control and Prevention. Methods An on-site survey of intensive care unit staff and infection control directors of 33 hospitals in the United States was conducted. The following data were collected: antimicrobial control policies; rates during the previous 12 months of methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, and ceftazidime-resistant Klebsiella pneumoniae; an implementation score of systems-level efforts to implement the guideline; staff attitudes toward practice guidelines; and observations of staff hand hygiene. Variables associated with resistance rates were examined for independent effects by using logistic regression. Results Resistance rates for S aureus, enterococci, and K pneumoniae were 52.5%, 18.2%, and 16.0%, respectively. Ten (30.3%) hospitals had an antibiotic control policy. No statistically significant correlation was observed between staff attitudes toward practice guidelines, observed hand hygiene behavior, or having an antibiotic use policy and resistance rates. In logistic regression analysis, higher scores on measures of systems-level efforts to implement the guideline were associated with lower rates of resistant S aureus and enterococci (P=.046). Conclusions Organizational-level factors independent of the practices of individual clinicians may be associated with rates of antimicrobial resistance. PMID:17322010

  16. The human microbiome as a reservoir of antimicrobial resistance.

    PubMed

    Penders, John; Stobberingh, Ellen E; Savelkoul, Paul H M; Wolffs, Petra F G

    2013-01-01

    The gut microbiota is amongst the most densely populated microbial ecosystem on earth. While the microbiome exerts numerous health beneficial functions, the high density of micro-organisms within this ecosystem also facilitates horizontal transfer of antimicrobial resistance (AMR) genes to potential pathogenic bacteria. Over the past decades antibiotic susceptibility testing of specific indicator bacteria from the microbiome, such as Escherichia coli, has been the method of choice in most studies. These studies have greatly enlarged our understanding on the prevalence and distribution of AMR and associated risk factors. Recent studies using (functional) metagenomics, however, highlighted the unappreciated diversity of AMR genes in the human microbiome and identified genes that had not been described previously. Next to metagenomics, more targeted approaches such as polymerase chain reaction for detection and quantification of AMR genes within a population are promising, in particular for large-scale epidemiological screening. Here we present an overview of the indigenous microbiota as a reservoir of AMR genes, the current knowledge on this "resistome" and the recent and upcoming advances in the molecular diagnostic approaches to unravel this reservoir. PMID:23616784

  17. Genetic Diversity and Antimicrobial Resistance of Escherichia coli from Human and Animal Sources Uncovers Multiple Resistances from Human Sources

    PubMed Central

    Ibekwe, A. Mark; Murinda, Shelton E.; Graves, Alexandria K.

    2011-01-01

    Escherichia coli are widely used as indicators of fecal contamination, and in some cases to identify host sources of fecal contamination in surface water. Prevalence, genetic diversity and antimicrobial susceptibility were determined for 600 generic E. coli isolates obtained from surface water and sediment from creeks and channels along the middle Santa Ana River (MSAR) watershed of southern California, USA, after a 12 month study. Evaluation of E. coli populations along the creeks and channels showed that E. coli were more prevalent in sediment compared to surface water. E. coli populations were not significantly different (P = 0.05) between urban runoff sources and agricultural sources, however, E. coli genotypes determined by pulsed-field gel electrophoresis (PFGE) were less diverse in the agricultural sources than in urban runoff sources. PFGE also showed that E. coli populations in surface water were more diverse than in the sediment, suggesting isolates in sediment may be dominated by clonal populations.Twenty four percent (144 isolates) of the 600 isolates exhibited resistance to more than one antimicrobial agent. Most multiple resistances were associated with inputs from urban runoff and involved the antimicrobials rifampicin, tetracycline, and erythromycin. The occurrence of a greater number of E. coli with multiple antibiotic resistances from urban runoff sources than agricultural sources in this watershed provides useful evidence in planning strategies for water quality management and public health protection. PMID:21687635

  18. Enterococcus Species in the Oral Cavity: Prevalence, Virulence Factors and Antimicrobial Susceptibility.

    PubMed

    Komiyama, Edson Yukio; Lepesqueur, Laura Soares Souto; Yassuda, Cinthia Gomes; Samaranayake, Lakshman P; Parahitiyawa, Nipuna B; Balducci, Ivan; Koga-Ito, Cristiane Yumi

    2016-01-01

    Enterococci are considered as transient constituent components of the oral microbiome that may cause a variety of oral and systemic infections. As there is sparse data on the oral enterococcal prevalence, we evaluated the Enterococcus spp. and their virulence attributes including antimicrobial resistance in a healthy Brazilian cohort. A total of 240 individuals in different age groups were studied (children 4-11 yrs, adolescents 12-17 yrs, young adults 18-29 yrs, adults 30-59 yrs, elderly over 60 yrs). Oral rinses were collected and isolates were identified by API 20 Strep and confirmed by 16S rDNA sequencing. E. faecalis isolates, in particular, were evaluated for virulence attributes such as their biofilm formation potential, and susceptibility to antimicrobials and an antiseptic, chlorhexidine gluconate. A total of 40 individuals (16.6%) and 10% children, 4% adolescents, 14% young adults, 30% adults, and 25% elderly carried oral enterococci. The oral enterococcal burden in adolescents was significantly lower than in the adults (p = 0.000) and elderly (p = 0.004). The proportion of carriers was higher among females (p = 0.001). E. faecalis was the most frequent isolate in all the age groups (p = 0.000), followed by E. durans and E. faecium. Whilst all the clinical isolates were able to form biofilms, only a proportion of them were able to produce lipase (92%), hemolysin (38%), and gelatinase (39%). Of all the isolates 53.8% were resistant to tetracycline, 12.3% to amoxicillin, 16.0% to ampicillin, 20.8% to chloramphenicol and 43.4% to erythromycin. None of the isolates were resistant to vancomycin. Our data suggest that in this Brazilian cohort the oral cavity may act as a significant reservoir of rather virulent and antibiotic resistant enterococci, with an increasing degree of carriage in the adults and elderly. Hence clinicians should be cognizant of this silent reservoir of virulent enterococci that may pose a particular threat of nosocomial infection.

  19. Strategic measures for the control of surging antimicrobial resistance in Hong Kong and mainland of China

    PubMed Central

    Cheng, Vincent CC; Wong, Sally CY; Ho, Pak-Leung; Yuen, Kwok-Yung

    2015-01-01

    Antimicrobial-resistant bacteria are either highly prevalent or increasing rapidly in Hong Kong and China. Treatment options for these bacteria are generally limited, less effective and more expensive. The emergence and dynamics of antimicrobial resistance genes in bacteria circulating between animals, the environment and humans are not entirely known. Nonetheless, selective pressure by antibiotics on the microbiomes of animal and human, and their associated environments (especially farms and healthcare institutions), sewage systems and soil are likely to confer survival advantages upon bacteria with antimicrobial-resistance genes, which may be further disseminated through plasmids or transposons with integrons. Therefore, antibiotic use must be tightly regulated to eliminate such selective pressure, including the illegalization of antibiotics as growth promoters in animal feed and regulation of antibiotic use in veterinary practice and human medicine. Heightened awareness of infection control measures to reduce the risk of acquiring resistant bacteria is essential, especially during antimicrobial use or institutionalization in healthcare facilities. The transmission cycle must be interrupted by proper hand hygiene, environmental cleaning, avoidance of undercooked or raw food and compliance with infection control measures by healthcare workers, visitors and patients, especially during treatment with antibiotics. In addition to these routine measures, proactive microbiological screening of hospitalized patients with risk factors for carrying resistant bacteria, including history of travel to endemic countries, transfer from other hospitals, and prolonged hospitalization; directly observed hand hygiene before oral intake of drugs, food and drinks; and targeted disinfection of high-touch or mutual-touch items, such as bed rails and bed curtains, are important. Transparency of surveillance data from each institute for public scrutiny provides an incentive for

  20. Strategic measures for the control of surging antimicrobial resistance in Hong Kong and mainland of China.

    PubMed

    Cheng, Vincent C C; Wong, Sally C Y; Ho, Pak-Leung; Yuen, Kwok-Yung

    2015-02-01

    Antimicrobial-resistant bacteria are either highly prevalent or increasing rapidly in Hong Kong and China. Treatment options for these bacteria are generally limited, less effective and more expensive. The emergence and dynamics of antimicrobial resistance genes in bacteria circulating between animals, the environment and humans are not entirely known. Nonetheless, selective pressure by antibiotics on the microbiomes of animal and human, and their associated environments (especially farms and healthcare institutions), sewage systems and soil are likely to confer survival advantages upon bacteria with antimicrobial-resistance genes, which may be further disseminated through plasmids or transposons with integrons. Therefore, antibiotic use must be tightly regulated to eliminate such selective pressure, including the illegalization of antibiotics as growth promoters in animal feed and regulation of antibiotic use in veterinary practice and human medicine. Heightened awareness of infection control measures to reduce the risk of acquiring resistant bacteria is essential, especially during antimicrobial use or institutionalization in healthcare facilities. The transmission cycle must be interrupted by proper hand hygiene, environmental cleaning, avoidance of undercooked or raw food and compliance with infection control measures by healthcare workers, visitors and patients, especially during treatment with antibiotics. In addition to these routine measures, proactive microbiological screening of hospitalized patients with risk factors for carrying resistant bacteria, including history of travel to endemic countries, transfer from other hospitals, and prolonged hospitalization; directly observed hand hygiene before oral intake of drugs, food and drinks; and targeted disinfection of high-touch or mutual-touch items, such as bed rails and bed curtains, are important. Transparency of surveillance data from each institute for public scrutiny provides an incentive for

  1. Strategic measures for the control of surging antimicrobial resistance in Hong Kong and mainland of China.

    PubMed

    Cheng, Vincent C C; Wong, Sally C Y; Ho, Pak-Leung; Yuen, Kwok-Yung

    2015-02-01

    Antimicrobial-resistant bacteria are either highly prevalent or increasing rapidly in Hong Kong and China. Treatment options for these bacteria are generally limited, less effective and more expensive. The emergence and dynamics of antimicrobial resistance genes in bacteria circulating between animals, the environment and humans are not entirely known. Nonetheless, selective pressure by antibiotics on the microbiomes of animal and human, and their associated environments (especially farms and healthcare institutions), sewage systems and soil are likely to confer survival advantages upon bacteria with antimicrobial-resistance genes, which may be further disseminated through plasmids or transposons with integrons. Therefore, antibiotic use must be tightly regulated to eliminate such selective pressure, including the illegalization of antibiotics as growth promoters in animal feed and regulation of antibiotic use in veterinary practice and human medicine. Heightened awareness of infection control measures to reduce the risk of acquiring resistant bacteria is essential, especially during antimicrobial use or institutionalization in healthcare facilities. The transmission cycle must be interrupted by proper hand hygiene, environmental cleaning, avoidance of undercooked or raw food and compliance with infection control measures by healthcare workers, visitors and patients, especially during treatment with antibiotics. In addition to these routine measures, proactive microbiological screening of hospitalized patients with risk factors for carrying resistant bacteria, including history of travel to endemic countries, transfer from other hospitals, and prolonged hospitalization; directly observed hand hygiene before oral intake of drugs, food and drinks; and targeted disinfection of high-touch or mutual-touch items, such as bed rails and bed curtains, are important. Transparency of surveillance data from each institute for public scrutiny provides an incentive for

  2. Antimicrobial Resistance in Mycobacterium tuberculosis: The Odd One Out.

    PubMed

    Eldholm, Vegard; Balloux, François

    2016-08-01

    Antimicrobial resistance (AMR) threats are typically represented by bacteria capable of extensive horizontal gene transfer (HGT). One clear exception is Mycobacterium tuberculosis (Mtb). It is an obligate human pathogen with limited genetic diversity and a low mutation rate which lacks any evidence for HGT. Such features should, in principle, reduce its ability to rapidly evolve AMR. We identify key features in its biology and epidemiology that allow it to overcome its low adaptive potential. We focus in particular on its innate resistance to drugs, its unusual life cycle, including an often extensive latent phase, and its ability to shelter from exposure to antimicrobial drugs within cavities it induces in the lungs. PMID:27068531

  3. Origin and Dissemination of Antimicrobial Resistance among Uropathogenic Escherichia coli.

    PubMed

    Nolan, Lisa K; Li, Ganwu; Logue, Catherine M

    2015-10-01

    Antimicrobial agents of various types have important bearing on the outcomes of microbial infections. These agents may be bacteriostatic or -cidal, exert their impact via various means, originate from a living organism or a laboratory, and appropriately be used in or on living tissue or not. Though the primary focus of this chapter is on resistance to the antimicrobial agents used to treat uropathogenic Escherichia coli (UPEC)-caused urinary tract infections (UTIs), some attention will be given to UPEC's resistance to silver-containing antiseptics, which may be incorporated into catheters to prevent foreign body-associated UTIs. PMID:26542043

  4. Antimicrobial resistance of Salmonella enterica isolated from bulk tank milk and milk filters in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salmonella isolates were recovered from bulk tank milk as part of the National Animal Health Monitoring System (NAHMS) Dairy 2002 and 2007 surveys. In-line milk filters were also tested in the 2007 survey. The objective of this study was to determine the prevalence of antimicrobial resistance among ...

  5. Effect of Antimicrobial Use in Agricultural Animals on Drug-resistant Foodborne Campylobacteriosis in Humans: A Systematic Literature Review.

    PubMed

    McCrackin, M A; Helke, Kristi L; Galloway, Ashley M; Poole, Ann Z; Salgado, Cassandra D; Marriott, Bernadette P

    2016-10-01

    Controversy continues concerning antimicrobial use in food animals and its relationship to drug-resistant infections in humans. We systematically reviewed published literature for evidence of a relationship between antimicrobial use in agricultural animals and drug-resistant foodborne campylobacteriosis in humans. Based on publications from the United States (U.S.), Canada and Denmark from 2010 to July 2014, 195 articles were retained for abstract review, 50 met study criteria for full article review with 36 retained for which data are presented. Two publications reported increase in macrolide resistance of Campylobacter coli isolated from feces of swine receiving macrolides in feed, and one of these described similar findings for tetracyclines and fluoroquinolones. A study in growing turkeys demonstrated increased macrolide resistance associated with therapeutic dosing with Tylan® in drinking water. One publication linked tetracycline-resistant C. jejuni clone SA in raw cow's milk to a foodborne outbreak in humans. No studies that identified farm antimicrobial use also traced antimicrobial-resistant Campylobacter from farm to fork. Recent literature confirms that on farm antibiotic selection pressure can increase colonization of animals with drug-resistant Campylobacter spp. but is inadequately detailed to establish a causal relationship between use of antimicrobials in agricultural animals and prevalence of drug-resistant foodborne campylobacteriosis in humans.

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

    PubMed

    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.

  7. Diversity of plasmids and antimicrobial resistance genes in multidrug-resistant Escherichia coli isolated from healthy companion animals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The presence and transfer of antimicrobial resistance genes from commensal bacteria in companion animals to more pathogenic bacteria may contribute to dissemination of antimicrobial resistance. The purpose of this study was to determine antimicrobial resistance gene content and the presence of gene...

  8. Strategies for achieving global collective action on antimicrobial resistance.

    PubMed

    Hoffman, Steven J; Caleo, Grazia M; Daulaire, Nils; Elbe, Stefan; Matsoso, Precious; Mossialos, Elias; Rizvi, Zain; Røttingen, John-Arne

    2015-12-01

    Global governance and market failures mean that it is not possible to ensure access to antimicrobial medicines of sustainable effectiveness. Many people work to overcome these failures, but their institutions and initiatives are insufficiently coordinated, led and financed. Options for promoting global collective action on antimicrobial access and effectiveness include building institutions, crafting incentives and mobilizing interests. No single option is sufficient to tackle all the challenges associated with antimicrobial resistance. Promising institutional options include monitored milestones and an inter-agency task force. A global pooled fund could be used to craft incentives and a special representative nominated as an interest mobilizer. There are three policy components to the problem of antimicrobials--ensuring access, conservation and innovation. To address all three components, the right mix of options needs to be matched with an effective forum and may need to be supported by an international legal framework.

  9. Strategies for achieving global collective action on antimicrobial resistance

    PubMed Central

    Caleo, Grazia M; Daulaire, Nils; Elbe, Stefan; Matsoso, Precious; Mossialos, Elias; Rizvi, Zain; Røttingen, John-Arne

    2015-01-01

    Abstract Global governance and market failures mean that it is not possible to ensure access to antimicrobial medicines of sustainable effectiveness. Many people work to overcome these failures, but their institutions and initiatives are insufficiently coordinated, led and financed. Options for promoting global collective action on antimicrobial access and effectiveness include building institutions, crafting incentives and mobilizing interests. No single option is sufficient to tackle all the challenges associated with antimicrobial resistance. Promising institutional options include monitored milestones and an inter-agency task force. A global pooled fund could be used to craft incentives and a special representative nominated as an interest mobilizer. There are three policy components to the problem of antimicrobials – ensuring access, conservation and innovation. To address all three components, the right mix of options needs to be matched with an effective forum and may need to be supported by an international legal framework. PMID:26668439

  10. Strategies for achieving global collective action on antimicrobial resistance.

    PubMed

    Hoffman, Steven J; Caleo, Grazia M; Daulaire, Nils; Elbe, Stefan; Matsoso, Precious; Mossialos, Elias; Rizvi, Zain; Røttingen, John-Arne

    2015-12-01

    Global governance and market failures mean that it is not possible to ensure access to antimicrobial medicines of sustainable effectiveness. Many people work to overcome these failures, but their institutions and initiatives are insufficiently coordinated, led and financed. Options for promoting global collective action on antimicrobial access and effectiveness include building institutions, crafting incentives and mobilizing interests. No single option is sufficient to tackle all the challenges associated with antimicrobial resistance. Promising institutional options include monitored milestones and an inter-agency task force. A global pooled fund could be used to craft incentives and a special representative nominated as an interest mobilizer. There are three policy components to the problem of antimicrobials--ensuring access, conservation and innovation. To address all three components, the right mix of options needs to be matched with an effective forum and may need to be supported by an international legal framework. PMID:26668439

  11. Detection of Rare Antimicrobial Resistance Profiles by Active and Passive Surveillance Approaches.

    PubMed

    Mather, Alison E; Reeve, Richard; Mellor, Dominic J; Matthews, Louise; Reid-Smith, Richard J; Dutil, Lucie; Haydon, Daniel T; Reid, Stuart W J

    2016-01-01

    Antimicrobial resistance (AMR) surveillance systems are generally not specifically designed to detect emerging resistances and usually focus primarily on resistance to individual drugs. Evaluating the diversity of resistance, using ecological metrics, allows the assessment of sampling protocols with regard to the detection of rare phenotypes, comprising combinations of resistances. Surveillance data of phenotypic AMR of Canadian poultry Salmonella Heidelberg and swine Salmonella Typhimurium var. 5- were used to contrast active (representative isolates derived from healthy animals) and passive (diagnostic isolates) surveillance and assess their suitability for detecting emerging resistance patterns. Although in both datasets the prevalences of resistance to individual antimicrobials were not significantly different between the two surveillance systems, analysis of the diversity of entire resistance phenotypes demonstrated that passive surveillance of diagnostic isolates detected more unique phenotypes. Whilst the most appropriate surveillance method will depend on the relevant objectives, under the conditions of this study, passive surveillance of diagnostic isolates was more effective for the detection of rare and therefore potentially emerging resistance phenotypes. PMID:27391966

  12. Detection of Rare Antimicrobial Resistance Profiles by Active and Passive Surveillance Approaches

    PubMed Central

    Mather, Alison E.; Reeve, Richard; Mellor, Dominic J.; Matthews, Louise; Reid-Smith, Richard J.; Haydon, Daniel T.; Reid, Stuart W. J.

    2016-01-01

    Antimicrobial resistance (AMR) surveillance systems are generally not specifically designed to detect emerging resistances and usually focus primarily on resistance to individual drugs. Evaluating the diversity of resistance, using ecological metrics, allows the assessment of sampling protocols with regard to the detection of rare phenotypes, comprising combinations of resistances. Surveillance data of phenotypic AMR of Canadian poultry Salmonella Heidelberg and swine Salmonella Typhimurium var. 5- were used to contrast active (representative isolates derived from healthy animals) and passive (diagnostic isolates) surveillance and assess their suitability for detecting emerging resistance patterns. Although in both datasets the prevalences of resistance to individual antimicrobials were not significantly different between the two surveillance systems, analysis of the diversity of entire resistance phenotypes demonstrated that passive surveillance of diagnostic isolates detected more unique phenotypes. Whilst the most appropriate surveillance method will depend on the relevant objectives, under the conditions of this study, passive surveillance of diagnostic isolates was more effective for the detection of rare and therefore potentially emerging resistance phenotypes. PMID:27391966

  13. The Evolving Role of Antimicrobial Stewardship in Management of Multidrug Resistant Infections.

    PubMed

    Goff, Debra A; File, Thomas M

    2016-06-01

    This article summarizes the current literature describing how antimicrobial stewardship interventions impact antimicrobial resistance. Discussion includes why we need stewardship, how to collaborate with team members, and the evidence of stewardship's impact on resistance.

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

    PubMed

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

    2011-08-01

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

  15. The Antimicrobial Resistance Crisis: Causes, Consequences, and Management

    PubMed Central

    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. PMID:25279369

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

    PubMed

    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.

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

    PubMed

    Quintana-Hayashi, Macarena P; Thakur, Siddhartha

    2012-01-01

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

  18. Acinetobacter baumannii: evolution of antimicrobial resistance-treatment options.

    PubMed

    Doi, Yohei; Murray, Gerald L; Peleg, Anton Y

    2015-02-01

    The first decade of the 20th century witnessed a surge in the incidence of infections due to several highly antimicrobial-resistant bacteria in hospitals worldwide. Acinetobacter baumannii is one such organism that turned from an occasional respiratory pathogen into a major nosocomial pathogen. An increasing number of A. baumannii genome sequences have broadened our understanding of the genetic makeup of these bacteria and highlighted the extent of horizontal transfer of DNA. Animal models of disease combined with bacterial mutagenesis have provided some valuable insights into mechanisms of A. baumannii pathogenesis. Bacterial factors known to be important for disease include outer membrane porins, surface structures including capsule and lipopolysaccharide, enzymes such as phospholipase D, iron acquisition systems, and regulatory proteins. A. baumannii has a propensity to accumulate resistance to various groups of antimicrobial agents. In particular, carbapenem resistance has become commonplace, accounting for the majority of A. baumannii strains in many hospitals today. Carbapenem-resistant strains are often resistant to all other routinely tested agents. Treatment of carbapenem-resistant A. baumannii infection therefore involves the use of combinations of last resort agents such as colistin and tigecycline, but the efficacy and safety of these approaches are yet to be defined. Antimicrobial-resistant A. baumannii has high potential to spread among ill patients in intensive care units. Early recognition and timely implementation of appropriate infection control measures is crucial in preventing outbreaks. PMID:25643273

  19. Strategies and molecular tools to fight antimicrobial resistance: resistome, transcriptome, and antimicrobial peptides

    PubMed Central

    Tavares, Letícia S.; Silva, Carolina S. F.; de Souza, Vinicius C.; da Silva, Vânia L.; Diniz, Cláudio G.; Santos, Marcelo O.

    2013-01-01

    The increasing number of antibiotic resistant bacteria motivates prospective research toward discovery of new antimicrobial active substances. There are, however, controversies concerning the cost-effectiveness of such research with regards to the description of new substances with novel cellular interactions, or description of new uses of existing substances to overcome resistance. Although examination of bacteria isolated from remote locations with limited exposure to humans has revealed an absence of antibiotic resistance genes, it is accepted that these genes were both abundant and diverse in ancient living organisms, as detected in DNA recovered from Pleistocene deposits (30,000 years ago). Indeed, even before the first clinical use of antibiotics more than 60 years ago, resistant organisms had been isolated. Bacteria can exhibit different strategies for resistance against antibiotics. New genetic information may lead to the modification of protein structure affecting the antibiotic carriage into the cell, enzymatic inactivation of drugs, or even modification of cellular structure interfering in the drug-bacteria interaction. There are still plenty of new genes out there in the environment that can be appropriated by putative pathogenic bacteria to resist antimicrobial agents. On the other hand, there are several natural compounds with antibiotic activity that may be used to oppose them. Antimicrobial peptides (AMPs) are molecules which are wide-spread in all forms of life, from multi-cellular organisms to bacterial cells used to interfere with microbial growth. Several AMPs have been shown to be effective against multi-drug resistant bacteria and have low propensity to resistance development, probably due to their unique mode of action, different from well-known antimicrobial drugs. These substances may interact in different ways with bacterial cell membrane, protein synthesis, protein modulation, and protein folding. The analysis of bacterial transcriptome

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

    PubMed

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

    2013-10-01

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

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

    PubMed

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

    2013-10-01

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

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

    PubMed

    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 (P<0.001) and MDR (P<0.001). Significant at P<0.003, was the consumption of raw meat for clavulanate-amoxicillin (OR: 9.57; 95% CI: 2.0-45.7) and third generation cephalosporin resistance (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

  3. Antimicrobial resistance: revisiting the "tragedy of the commons".

    PubMed

    2010-11-01

    When the NDM1 enzyme-containing "superbugs" struck in India, Pakistan and the United Kingdom earlier this year, media reports blamed medical tourism for its spread. But in this interview, Professor John Conly argues that the overuse and misuse of antibiotics leading to antimicrobial resistance - the theme of World Health Day 2011 - is the more important topic. PMID:21076559

  4. Antimicrobial resistance: revisiting the "tragedy of the commons".

    PubMed

    2010-11-01

    When the NDM1 enzyme-containing "superbugs" struck in India, Pakistan and the United Kingdom earlier this year, media reports blamed medical tourism for its spread. But in this interview, Professor John Conly argues that the overuse and misuse of antibiotics leading to antimicrobial resistance - the theme of World Health Day 2011 - is the more important topic.

  5. Evaluation of antimicrobial resistance of bovine bacteria to antibiotics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antimicrobial resistance (AMR) is one of the most formidable threats to human medicine today. Therefore, the research objective is to evaluate the susceptibility of Staphylococcus species isolated from beef cows to 12 antibiotics commonly used in treating human and animal infections. This research w...

  6. Repeated nationwide point-prevalence surveys of antimicrobial use in Swedish hospitals: data for actions 2003-2010.

    PubMed

    Skoog, Gunilla; Struwe, Johan; Cars, Otto; Hanberger, Håkan; Odenholt, Inga; Prag, Mårten; Skärlund, Katarina; Ulleryd, Peter; Erntell, Mats

    2016-06-23

    This study sought to analyse antimicrobial pressure, indications for treatment, and compliance with treatment recommendations and to identify possible problem areas where inappropriate use could be improved through interventions by the network of the local Swedish Strategic Programme Against Antibiotic Resistance (Strama) groups. Five point-prevalence surveys were performed in between 49 and 72 participating hospitals from 2003 to 2010. Treatments were recorded for 19 predefined diagnosis groups and whether they were for community-acquired infection, hospital-acquired infection, or prophylaxis. Approximately one-third of inpatients were treated with antimicrobials. Compliance with guidelines for treatment of community-acquired pneumonia with narrow-spectrum penicillin was 17.0% during baseline 2003-2004, and significantly improved to 24.2% in 2010. Corresponding figures for quinolone use in uncomplicated cystitis in women were 28.5% in 2003-2004, and significantly improved, decreasing to 15.3% in 2010. The length of surgical prophylaxis improved significantly when data for a single dose and 1 day were combined, from 56.3% in 2003-2004 to 66.6% in 2010. Improved compliance was possibly the effect of active local feedback, repeated surveys, and increasing awareness of antimicrobial resistance. Strama groups are important for successful local implementation of antimicrobial stewardship programs in Sweden. PMID:27367646

  7. Is antimicrobial resistance also subject to globalization?

    PubMed

    Schito, G C

    2002-01-01

    In recent years one of the more alarming aspects of clinical microbiology has been the dramatic increase in the incidence of resistance to antibacterial agents among pathogens causing nosocomial as well as community-acquired infections. There are profound geographic differences in the incidence of resistance among pathogens of the respiratory tract, only some of which can be explained by the local use of antibiotics. A high percentage of Moraxella catarrhalis strains produce beta-lactamase and are thus resistant to many beta-lactam antibiotics. In contrast, beta-lactamase production among strains of Haemophilus influenzae rarely reaches more than 30% around the world. Methicillin-resistance in Staphylococcus aureus is a common and increasing problem in hospitals but its extent varies both locally and nationally. Resistance is usually associated with the local spread of resistant strains. High standards of hygiene in hospitals can prevent the spread of such strains but once established they can be difficult to eradicate. Although Streptococcus pyogenes remains highly susceptible to penicillins, even after many decades of their use, resistance to macrolides has occurred. This resistance can rise and fall. Although the increase of macrolide resistance in S. pyogenes can often be associated with an increase in the use of these drugs, this is not always so. In some cases it has been shown to be caused by the spread of one or more resistant clones. Eradication of these clones can reduce the level of resistance markedly. Resistance to both macrolides and penicillins among strains of Streptococcus pneumoniae is seen world-wide but is highly variable from country to country. Local habits of drug usage may play a part. In Italy, for example, there is preference for the use of parenteral third-generation cephalosporins for some severe infections and there is a corresponding low level of penicillin-resistance among pneumococci.

  8. Antimicrobial resistance and genetic characterization of fluoroquinolone resistance of Pseudomonas aeruginosa isolated from canine infections.

    PubMed

    Rubin, J; Walker, R D; Blickenstaff, K; Bodeis-Jones, S; Zhao, S

    2008-09-18

    Infections with antimicrobial-resistant bacteria are a great challenge in both human and veterinary medicine. The purpose of this study was to determine antimicrobial susceptibility of 106 strains of Pseudomonas aeruginosa isolated from dogs with otitis and pyoderma from 2003 to 2006 in the United States. Three antimicrobial panels, including 6 classes and 32 antimicrobial agents, were used. A wide range of susceptibility patterns were noted with some isolates being resistant to between 8 and 28 (mean 16) of the antimicrobials tested. Among the beta-lactams, all isolates were resistant to ampicillin, cefoxitin, cefpodoxime, cephalothin and cefazolin followed by amoxicillin/clavulanic acid (99%), ceftiofur (97%), ceftriaxone (39%), cefotaxime (26%), and cefotaxime/clavulanic acid (20%), whereas less than 7% of isolates were resistant to ceftazidime/clavulanic acid, ceftazidime, piperacillin/tazobactam or cefepime. Two isolates were resistant to the carbapenems. Among the quinolones and fluoroquinolones, the most isolates were resistant to naladixic acid (96%), followed by orbifloxacin (52%), difloxacin (43%), enrofloxacin (31%), marbofloxacin (27%), gatifloxacin (23%), levofloxacin (21%), and ciprofloxacin (16%). Among the aminoglycosides, the most resistance was seen to kanamycin (90%), followed by streptomycin (69%), gentamicin (7%), and amikacin (3%). Of the remaining antimicrobials 100% of the isolates were resistant to chloramphenicol followed by tetracycline (98%), trimethoprim/sulfamethoxazole (57%), and sulfisoxazole (51%). Point mutations were present in gyrA, gyrB, parC, and/or parE genes among 34 of the 102 naladixic acid-resistant isolates. Two isolates contained class 1 integrons carrying aadA gene conferring streptomycin and spectinomycin resistance. The findings suggest that many antimicrobial agents commonly used in companion animals may not constitute appropriate therapy for canine pseudomonas infections.

  9. The antimicrobial resistance monitoring and research (ARMoR) program: the US Department of Defense response to escalating antimicrobial resistance.

    PubMed

    Lesho, Emil P; Waterman, Paige E; Chukwuma, Uzo; McAuliffe, Kathryn; Neumann, Charlotte; Julius, Michael D; Crouch, Helen; Chandrasekera, Ruvani; English, Judith F; Clifford, Robert J; Kester, Kent E

    2014-08-01

    Responding to escalating antimicrobial resistance (AMR), the US Department of Defense implemented an enterprise-wide collaboration, the Antimicrobial Resistance Monitoring and Research Program, to aid in infection prevention and control. It consists of a network of epidemiologists, bioinformaticists, microbiology researchers, policy makers, hospital-based infection preventionists, and healthcare providers who collaborate to collect relevant AMR data, conduct centralized molecular characterization, and use AMR characterization feedback to implement appropriate infection prevention and control measures and influence policy. A particularly concerning type of AMR, carbapenem-resistant Enterobacteriaceae, significantly declined after the program was launched. Similarly, there have been no further reports or outbreaks of another concerning type of AMR, colistin resistance in Acinetobacter, in the Department of Defense since the program was initiated. However, bacteria containing AMR-encoding genes are increasing. To update program stakeholders and other healthcare systems facing such challenges, we describe the processes and impact of the program. PMID:24795331

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

    PubMed

    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.

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

    PubMed

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

    2014-12-01

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

  12. High prevalence of multidrug-resistance uropathogenic Escherichia coli strains, Isfahan, Iran

    PubMed Central

    Dehbanipour, Razieh; Rastaghi, Sedighe; Sedighi, Mansour; Maleki, Nafiseh; Faghri, Jamshid

    2016-01-01

    Background and Objectives: Urinary tract infection (UTI) is one of the most frequent infectious diseases and can occur in all age groups. Escherichia coli is the main cause of this infection. Multiple resistances to antimicrobial agents are increasing quickly in E. coli isolates and may complicate therapeutic strategies for UTI. The aim of this study was to determine the antibiotic resistance pattern and the multidrug-resistance (MDR) phenotypes in uropathogenic E. coli (UPEC). Materials and Methods: A total of 135 UPEC isolates were collected from both outpatients (91 isolates) and inpatients (44 isolates) between September, 2012 and February, 2013. In order to determine the MDR among UPEC isolates, we have tested 15 antimicrobial agents and antibiotic susceptibility was done by Kirby-Bauer disk diffusion method. Results: The percentage of MDR isolates (resistant to at least three drug classes such as aminoglycosides, fluoroquinolones, penicillins, cephalosporins, or carbapenems) was 68% in the inpatients and 61% in the outpatients. Antibiotic resistance to ampicillin, ceftazidim, nalidixic acid, and trimethoprim/sulfamethoxazole were higher than 50%. Amikacin, nitrofurantoin, and gentamicin showed markedly greater activity (89.1%, 85.9%, and 82.4% sensitivity, respectively) than other antimicrobial agents. Resistance to meropenem did show either in outpatients or in inpatients. Interpretation and Conclusions: The high prevalence of drug resistance among UTI patients calls for continuous monitoring of the incidence of drug resistance for appropriate empiric selection of antibiotic therapy. Empirical treatment of UTIs should be relied on susceptibility patterns from local studies. PMID:27003964

  13. Australian Group on Antimicrobial Resistance Australian Enterobacteriaceae Sepsis Outcome Programme annual report, 2014.

    PubMed

    Bell, Jan M; Turnidge, John D; Coombs, Geoffrey W; Daley, Denise A; Gottlieb, Thomas; Robson, Jenny; George, Narelle

    2016-01-01

    The Australian Group on Antimicrobial Resistance performs regular period-prevalence studies to monitor changes in antimicrobial resistance in selected enteric Gram-negative pathogens. The 2014 survey was the second year to focus on blood stream infections. During 2014, 5,798 Enterobacteriaceae species isolates were tested using commercial automated methods (Vitek 2, BioMérieux; Phoenix, BD) and results were analysed using the Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints (January 2015). Of the key resistances, non-susceptibility to the third-generation cephalosporin, ceftriaxone, was found in 9.0%/9.0% of Escherichia coli (CLSI/EUCAST criteria) and 7.8%/7.8% of Klebsiella pneumoniae, and 8.0%/8.0% K. oxytoca. Non-susceptibility rates to ciprofloxacin were 10.4%/11.6% for E. coli, 5.0%/7.7% for K. pneumoniae, 0.4%/0.4% for K. oxytoca, and 3.5%/6.5% in Enterobacter cloacae. Resistance rates to piperacillin-tazobactam were 3.2%/6.8%, 4.8%/7.2%, 11.1%/11.5%, and 19.0%/24.7% for the same 4 species respectively. Fourteen isolates were shown to harbour a carbapenemase gene, 7 blaIMP-4, 3 blaKPC-2, 3 blaVIM-1, 1 blaNDM-4, and 1 blaOXA-181-lke. PMID:27522134

  14. The role of drinking water in the transmission of antimicrobial-resistant E. coli.

    PubMed

    Coleman, B L; Salvadori, M I; McGeer, A J; Sibley, K A; Neumann, N F; Bondy, S J; Gutmanis, I A; McEwen, S A; Lavoie, M; Strong, D; Johnson, I; Jamieson, F B; Louie, M

    2012-04-01

    To determine whether drinking water contaminated with antimicrobial-resistant E. coli is associated with the carriage of resistant E. coli, selected households sending water samples to Ontario and Alberta laboratories in 2005-2006 were asked to participate in a cross-sectional study. Household members aged ≥12 years were asked to complete a questionnaire and to submit a rectal swab. In 878 individuals, 41% carried a resistant strain of E. coli and 28% carried a multidrug-resistant strain. The risk of carriage of resistant E. coli was 1·26 times higher for users of water contaminated with resistant E. coli. Other risk factors included international travel [prevalence ratio (PR) 1·33], having a child in nappies (PR 1·33), being male (PR 1·33), and frequent handling of raw red meats (PR 1·10). Protecting private water sources (e.g. by improving systems to test and treat them) may help slow the emergence of antimicrobial resistance in E. coli.

  15. Relationship between super antigenicity, antimicrobial resistance and origin of Staphylococcus aureus isolated

    PubMed Central

    Corredor Arias, Luisa Fernanda; Luligo Espinal, Jenna Samara; Santacruz Ibarra, Jorge Javier; Álvarez Aldana, Adalucy

    2016-01-01

    Introduction: Staphylococcus aureus is a pathogen that causes food poisoning as well as hospital and community acquired infections. Objective: Establish the profile of superantigen genes among hospital isolates in relation to clinical specimen type, susceptibility to antibiotics and hospital or community acquisition. Methods: Eighty one isolates obtained from patients at Colombian hospital, were classified by antimicrobial susceptibility, specimen type and hospital or community acquired . The PCR uniplex and multiplex was used for detection of 22 superantigen genes (18 enterotoxins, tsst-1 and three exfoliative toxins). Results: Ninety five point one percent of isolates harbored one or more of the genes with an average of 5.6 genes. Prevalence of individual genes was variable and the most prevalent was seg (51.9%). Thirty nine genotypes were obtained, and the genotype gimnou (complete egc cluster) was the most prevalent alone (16.0%) and in association with other genes (13.6%). The correlation between presence of superantigens and clinical specimen or antimicrobial susceptibility showed no significant difference. But there was significant difference between presence of superantigens and the origin of the isolates, hospital or community acquired (p= 0.049). Conclusions: The results show the variability of the superantigen genes profile in hospital isolates and shows no conclusive relationship with the clinical sample type and antimicrobial susceptibility, but there was correlation with community and hospital isolates. The analysis of the interplay between virulence, epidemic and antibiotic resistance of bacterial populations is needed to predict the future of infectious diseases. PMID:27226659

  16. Prevalence and antimicrobial susceptibility of major foodborne pathogens in imported seafood.

    PubMed

    Wang, Fei; Jiang, Lin; Yang, Qianru; Han, Feifei; Chen, Siyi; Pu, Shuaihua; Vance, Amanda; Ge, Beilei

    2011-09-01

    Seafood is a leading commodity implicated in foodborne disease outbreaks in the United States. Seafood importation rose dramatically in the past 3 decades and now contributes to more than 80% of the total U.S. seafood supply. However, limited data are available on the microbiological safety of imported seafood. In this study, we obtained a total of 171 salmon, shrimp, and tilapia samples imported from 12 countries in three retail stores in Baton Rouge, LA. The total microbial population and the prevalence and antimicrobial susceptibilities of six major foodborne-pathogen genera (Campylobacter, Escherichia coli, Listeria, Salmonella, Shigella, and Vibrio) were determined. The aerobic plate counts (APC) for the 171 samples averaged 4.96 log CFU/g, with samples from Chile carrying the highest mean APC of 6.53 log CFU/g and fresh samples having a significantly higher mean APC than frozen ones (P < 0.0001). There were 27 samples (15.8%) with unacceptable microbiological quality (APC > 7 log CFU/g). By culture, no sample tested positive for Campylobacter coli, Shigella, or Vibrio vulnificus. Campylobacter jejuni and Salmonella enterica serovar Typhimurium were each recovered once from farm-raised tilapia from China. By PCR, 17.5 and 32.2% of the samples were positive for Salmonella and Shigella, respectively. The overall prevalence rates of other target bacteria were low, ranging from 4.1% for Listeria monocytogenes to 9.4% for E. coli. All of the Vibrio parahaemolyticus isolates recovered were from shrimp, and 63.3% showed intermediate resistance to ampicillin. Both C. jejuni isolates possessed a rare resistance to gentamicin, while 75% of L. monocytogenes isolates were resistant to nitrofurantoin. Taken together, these findings suggest potential food safety hazards associated with imported seafood and warrant further large-scale studies. PMID:21902913

  17. Salmonella enterica Genomics and Antimicrobial Resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salmonella is a prevalent food-borne pathogen and a model system for the study of virulence and pathogenesis. The development of DNA microarray technology has furthered investigation of genome organization that leads to the variations in Salmonella serotypes. There are over 2400 Salmonella serotypes...

  18. Antimicrobial resistance induced by genetic changes

    PubMed Central

    2009-01-01

    Decoding the mechanisms of resistance to antibiotics is essential in fighting a phenomenon, which is amplifying everyday due to the uncontrolled excessive and many times unjustified use of anti–microbial substances. At present it has become a matter of public health, together with the resistance of Mycobacterium tuberculosis to tuberculostatic or the spreading of the AIDS virus which not only affects the European countries but the entire globe. This paper presents the genic mutations taking place at the level of bacterial chromosome and inducing the resistance to antibiotics. PMID:20108530

  19. Insect Antimicrobial Peptide Complexes Prevent Resistance Development in Bacteria

    PubMed Central

    Chernysh, Sergey; Gordya, Natalia; Suborova, Tatyana

    2015-01-01

    In recent decades much attention has been paid to antimicrobial peptides (AMPs) as natural antibiotics, which are presumably protected from resistance development in bacteria. However, experimental evolution studies have revealed prompt resistance increase in bacteria to any individual AMP tested. Here we demonstrate that naturally occurring compounds containing insect AMP complexes have clear advantage over individual peptide and small molecule antibiotics in respect of drug resistance development. As a model we have used the compounds isolated from bacteria challenged maggots of Calliphoridae flies. The compound isolated from blow fly Calliphora vicina was found to contain three distinct families of cell membrane disrupting/permeabilizing peptides (defensins, cecropins and diptericins), one family of proline rich peptides and several unknown antimicrobial substances. Resistance changes under long term selective pressure of the compound and reference antibiotics cefotaxime, meropenem and polymyxin B were tested using Escherichia coli, Klebsiella pneumonia and Acinetobacter baumannii clinical strains. All the strains readily developed resistance to the reference antibiotics, while no signs of resistance growth to the compound were registered. Similar results were obtained with the compounds isolated from 3 other fly species. The experiments revealed that natural compounds containing insect AMP complexes, in contrast to individual AMP and small molecule antibiotics, are well protected from resistance development in bacteria. Further progress in the research of natural AMP complexes may provide novel solutions to the drug resistance problem. PMID:26177023

  20. Highly variable patterns of antimicrobial resistance in commensal Escherichia coli isolates from pigs, sympatric rodents, and flies.

    PubMed

    Literak, Ivan; Dolejska, Monika; Rybarikova, Jana; Cizek, Alois; Strejckova, Pavla; Vyskocilova, Martina; Friedman, Miroslava; Klimes, Jiri

    2009-09-01

    Antimicrobial-resistant Escherichia coli strains from pigs, sympatric rodents, and flies from two large farms in the Czech Republic with different antibiotic exposure histories were characterized based on antimicrobial resistance genes, integrons, and macrorestriction DNA profiles. Isolates of E. coli were tested for susceptibility to 12 antimicrobial agents according to the standard disk diffusion method. In resistant isolates, polymerase chain reaction was used to detect antibiotic resistance genes, integrase genes, and gene cassettes. Pulsed-field gel electrophoresis (PFGE) was used for molecular subtyping of E. coli. In farm A (long-term use of amoxicillin only), 75% (n = 198), 65% (n = 49), 11% (n = 139), and 82% (n = 177) of E. coli isolates from piglets, sows, sympatric rodents, and flies, respectively, were antibiotic resistant. In farm B (various antibiotics commonly used), 53% (n = 154), 69% (n = 98), and 54% (n = 74) of E. coli isolates from piglets, sows, and sympatric rodents, respectively, were antibiotic resistant. In both farms, the highest resistance prevalence was to tetracycline, and resistance patterns of isolates were greatly variable. Isolates with the same resistance phenotype, genes, and PFGE profile were found in pigs and flies. Isolates from rodents showed unique PFGE profiles. Close contact of sympatric rodents and flies with pigs or their products was associated with colonization of rodents and flies with resistant bacteria or transfer of resistance genes found in pig intestinal flora.

  1. Coping with antibiotic resistance: combining nanoparticles with antibiotics and other antimicrobial agents.

    PubMed

    Allahverdiyev, Adil M; Kon, Kateryna Volodymyrivna; Abamor, Emrah Sefik; Bagirova, Malahat; Rafailovich, Miriam

    2011-11-01

    The worldwide escalation of bacterial resistance to conventional medical antibiotics is a serious concern for modern medicine. High prevalence of multidrug-resistant bacteria among bacteria-based infections decreases effectiveness of current treatments and causes thousands of deaths. New improvements in present methods and novel strategies are urgently needed to cope with this problem. Owing to their antibacterial activities, metallic nanoparticles represent an effective solution for overcoming bacterial resistance. However, metallic nanoparticles are toxic, which causes restrictions in their use. Recent studies have shown that combining nanoparticles with antibiotics not only reduces the toxicity of both agents towards human cells by decreasing the requirement for high dosages but also enhances their bactericidal properties. Combining antibiotics with nanoparticles also restores their ability to destroy bacteria that have acquired resistance to them. Furthermore, nanoparticles tagged with antibiotics have been shown to increase the concentration of antibiotics at the site of bacterium-antibiotic interaction, and to facilitate binding of antibiotics to bacteria. Likewise, combining nanoparticles with antimicrobial peptides and essential oils generates genuine synergy against bacterial resistance. In this article, we aim to summarize recent studies on interactions between nanoparticles and antibiotics, as well as other antibacterial agents to formulate new prospects for future studies. Based on the promising data that demonstrated the synergistic effects of antimicrobial agents with nanoparticles, we believe that this combination is a potential candidate for more research into treatments for antibiotic-resistant bacteria.

  2. Macrolides and lincosamides in cattle and pigs: use and development of antimicrobial resistance.

    PubMed

    Pyörälä, Satu; Baptiste, Keith Edward; Catry, Boudewijn; van Duijkeren, Engeline; Greko, Christina; Moreno, Miguel A; Pomba, M Constança Matias Ferreira; Rantala, Merja; Ružauskas, Modestas; Sanders, Pascal; Threlfall, E John; Torren-Edo, Jordi; Törneke, Karolina

    2014-05-01

    Macrolides and lincosamides are important antibacterials for the treatment of many common infections in cattle and pigs. Products for in-feed medication with these compounds in combination with other antimicrobials are commonly used in Europe. Most recently approved injectable macrolides have very long elimination half-lives in both pigs and cattle, which allows once-only dosing regimens. Both in-feed medication and use of long-acting injections result in low concentrations of the active substance for prolonged periods, which causes concerns related to development of antimicrobial resistance. Acquired resistance to macrolides and lincosamides among food animal pathogens, including some zoonotic bacteria, has now emerged. A comparison of studies on the prevalence of resistance is difficult, since for many micro-organisms no agreed standards for susceptibility testing are available. With animal pathogens, the most dramatic increase in resistance has been seen in the genus Brachyspira. Resistance towards macrolides and lincosamides has also been detected in staphylococci isolated from pigs and streptococci from cattle. This article reviews the use of macrolides and lincosamides in cattle and pigs, as well as the development of resistance in target and some zoonotic pathogens. The focus of the review is on European conditions.

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

    PubMed

    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. PMID:25809180

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

    PubMed

    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.

  5. Antimicrobial resistance and the ecology of Escherichia coli plasmids.

    PubMed Central

    Platt, D. J.; Sommerville, J. S.; Kraft, C. A.; Timbury, M. C.

    1984-01-01

    Four hundred and seven clinical isolates of Escherichia coli were examined for the presence of plasmids. These isolates comprised 189 which were collected irrespective of antimicrobial resistance (VP) and 218 which were collected on the basis of high-level trimethoprim resistance (TPR). The VP isolates were divided into drug sensitive (VPS) and drug-resistant (VPR) subpopulations. Plasmids were detected in 88% of VP isolates (81% of VPS and 94% of VPR) and 98% of TPR isolates. The distribution of plasmids in both groups and subpopulations was very similar. However, there were small but statistically significant differences between the plasmid distributions. These showed that more isolates in the resistant groups harboured plasmids than in the sensitive subpopulation (VPS) and that the number of plasmids carried by resistant isolates was greater. Multiple drug resistance was significantly more common among TPR isolates than the VPR subpopulation and this was paralleled by increased numbers of plasmids. Fifty-eight per cent of VPR and 57% of TPR isolates transferred antimicrobial resistance and plasmids to E. coli K12. Of the R+ isolates, 60% carried small plasmids (MW less than 20Md) and 52% of these co-transferred with R-plasmids. These results are discussed. PMID:6389695

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

    PubMed

    Gerbin, C Sachi

    2014-01-01

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

  7. Enhancing US-Japan Cooperation to Combat Antimicrobial Resistance

    PubMed Central

    2014-01-01

    The Global Health Security Agenda (GHSA) is aimed at preventing, detecting, and responding to infectious disease threats. To move toward these goals, the United States has committed to partner with at least 30 countries around the world. One of the objectives of the GHSA includes “[p]reventing the emergence and spread of antimicrobial drug resistant organisms.” Antimicrobial resistance (AMR) has become a growing global health security problem, with inappropriate use of antimicrobial medications in humans and animals and a lack of new antimicrobial medications contributing to this problem. While AMR is a growing global concern, working on it regionally can make this multifaceted problem more manageable. The United States and Japan, both world leaders in the life sciences, are close allies that have established cooperative programs in medical research and global health that can be used to work on combating AMR and advance the GHSA. Although the United States and Japan have cooperated on health issues in the past, their cooperation on the growing problem of AMR has been limited. Their existing networks, cooperative programs, and close relationships can and should be used to work on combating this expanding problem. PMID:25470465

  8. Antimicrobial Peptide Resistance Mechanisms of Gram-Positive Bacteria

    PubMed Central

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

    2014-01-01

    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. PMID:25419466

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

    PubMed Central

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

    2015-01-01

    Background 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. Results 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. Conclusions 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

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

    PubMed Central

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

    2014-01-01

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

  11. Antimicrobial resistance and virulence gene profiles in multi-drug resistant enterotoxigenic Escherichia coli isolated from pigs with post-weaning diarrhoea.

    PubMed

    Smith, M G; Jordan, D; Chapman, T A; Chin, J J-C; Barton, M D; Do, T N; Fahy, V A; Fairbrother, J M; Trott, D J

    2010-10-26

    This study aimed to characterize antimicrobial resistance and virulence genes in multi-drug resistant enterotoxigenic Escherichia coli (ETEC) isolates (n=117) collected from porcine post-weaning diarrhoea cases in Australia (1999-2005). Isolates were serotyped, antibiogram-phenotyped for 12 antimicrobial agents and genotyped by PCR for 30 plasmid-mediated antimicrobial resistance genes (ARGs), 22 intestinal and 38 extraintestinal E. coli virulence genes (VGs). Nine serogroups were identified, the most prevalent being O149 (46.2%), O141 (11.2%) and Ont (31.6%). None of the isolates showed resistance to ceftiofur or enrofloxacin and 9.4% were resistant to florfenicol. No corresponding extended-spectrum/AmpC β-lactamase, fluoroquinolone or floR ARGs were detected. An antimicrobial resistance index (ARI) was calculated from the combined data with a weighting for each antimicrobial agent dependent upon its significance to human health. Serogroup O141 isolates had a significantly higher ARI due to an elevated prevalence of aminoglycoside ARGs and possession of more virulence genes (VGs), including ExPEC or EHEC adhesins (bmaE, sfa/focDE, fimH, ihA) in toxin-producing strains that lacked the normally associated F4 and F18 fimbriae. Few associations between ARGs and VGs were apparent, apart from tetC, sfa/focDE and ompT which, for a sub-set of O141 isolates, suggest possible plasmid acquisition from ExPEC. The multi-drug resistant ETEC ARG/VG profiles indicate a high probability of considerable strain and plasmid diversity, reflecting various selection pressures at the individual farm level rather than emergence and lateral spread of MDR resistant/virulent clones. PMID:20688440

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

    PubMed

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

    2016-07-01

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

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

    PubMed

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

    2016-07-01

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

  14. Genetic characterization of antimicrobial resistance in coagulase-negative staphylococci from bovine mastitis milk.

    PubMed

    Frey, Yvonne; Rodriguez, Joan Peña; Thomann, Andreas; Schwendener, Sybille; Perreten, Vincent

    2013-04-01

    Coagulase-negative staphylococci (CNS; n=417) were isolated from bovine milk and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Nineteen different species were identified, and Staphylococcus xylosus, Staphylococcus chromogenes, Staphylococcus haemolyticus, and Staphylococcus sciuri were the most prevalent species. Resistance to oxacillin (47.0% of the isolates), fusidic acid (33.8%), tiamulin (31.9%), penicillin (23.3%), tetracycline (15.8%), streptomycin (9.6%), erythromycin (7.0%), sulfonamides (5%), trimethoprim (4.3%), clindamycin (3.4%), kanamycin (2.4%), and gentamicin (2.4%) was detected. Resistance to oxacillin was attributed to the mecA gene in 9.7% of the oxacillin-resistant isolates. The remaining oxacillin-resistant CNS did not contain the mecC gene or mecA1 promoter mutations. The mecA gene was detected in Staphylococcus fleurettii, Staphylococcus epidermidis, Staph. haemolyticus, and Staph. xylosus. Resistance to tetracycline was attributed to the presence of tet(K) and tet(L), penicillin resistance to blaZ, streptomycin resistance to str and ant(6)-Ia, and erythromycin resistance to erm(C), erm(B), and msr. Resistance to tiamulin and fusidic acid could not be attributed to an acquired resistance gene. In total, 15.1% of the CNS isolates were multidrug resistant (i.e., resistant to 2 or more antimicrobials). The remaining CNS isolates were susceptible to antimicrobials commonly used in mastitis treatment. Methicillin-resistant CNS isolates were diverse, as determined by mecA gene sequence analysis, staphylococcal cassette chromosome mec typing, and pulsed-field gel electrophoresis. Arginine catabolic mobile element types 1 and 3 were detected in both methicillin-resistant and methicillin-susceptible Staph. epidermidis and were associated with sequence types ST59 and ST111. Because this study revealed the presence of multidrug-resistant CNS in a heterogeneous CNS population, we recommend antibiogram analysis

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

    PubMed Central

    2009-01-01

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

  16. Enterococcus Species in the Oral Cavity: Prevalence, Virulence Factors and Antimicrobial Susceptibility

    PubMed Central

    Komiyama, Edson Yukio; Samaranayake, Lakshman P.; Parahitiyawa, Nipuna B.; Balducci, Ivan

    2016-01-01

    Enterococci are considered as transient constituent components of the oral microbiome that may cause a variety of oral and systemic infections. As there is sparse data on the oral enterococcal prevalence, we evaluated the Enterococcus spp. and their virulence attributes including antimicrobial resistance in a healthy Brazilian cohort. A total of 240 individuals in different age groups were studied (children 4–11 yrs, adolescents 12–17 yrs, young adults 18–29 yrs, adults 30–59 yrs, elderly over 60 yrs). Oral rinses were collected and isolates were identified by API 20 Strep and confirmed by 16S rDNA sequencing. E. faecalis isolates, in particular, were evaluated for virulence attributes such as their biofilm formation potential, and susceptibility to antimicrobials and an antiseptic, chlorhexidine gluconate. A total of 40 individuals (16.6%) and 10% children, 4% adolescents, 14% young adults, 30% adults, and 25% elderly carried oral enterococci. The oral enterococcal burden in adolescents was significantly lower than in the adults (p = 0.000) and elderly (p = 0.004). The proportion of carriers was higher among females (p = 0.001). E. faecalis was the most frequent isolate in all the age groups (p = 0.000), followed by E. durans and E. faecium. Whilst all the clinical isolates were able to form biofilms, only a proportion of them were able to produce lipase (92%), hemolysin (38%), and gelatinase (39%). Of all the isolates 53.8% were resistant to tetracycline, 12.3% to amoxicillin, 16.0% to ampicillin, 20.8% to chloramphenicol and 43.4% to erythromycin. None of the isolates were resistant to vancomycin. Our data suggest that in this Brazilian cohort the oral cavity may act as a significant reservoir of rather virulent and antibiotic resistant enterococci, with an increasing degree of carriage in the adults and elderly. Hence clinicians should be cognizant of this silent reservoir of virulent enterococci that may pose a particular threat of nosocomial infection

  17. Enterococcus Species in the Oral Cavity: Prevalence, Virulence Factors and Antimicrobial Susceptibility.

    PubMed

    Komiyama, Edson Yukio; Lepesqueur, Laura Soares Souto; Yassuda, Cinthia Gomes; Samaranayake, Lakshman P; Parahitiyawa, Nipuna B; Balducci, Ivan; Koga-Ito, Cristiane Yumi

    2016-01-01

    Enterococci are considered as transient constituent components of the oral microbiome that may cause a variety of oral and systemic infections. As there is sparse data on the oral enterococcal prevalence, we evaluated the Enterococcus spp. and their virulence attributes including antimicrobial resistance in a healthy Brazilian cohort. A total of 240 individuals in different age groups were studied (children 4-11 yrs, adolescents 12-17 yrs, young adults 18-29 yrs, adults 30-59 yrs, elderly over 60 yrs). Oral rinses were collected and isolates were identified by API 20 Strep and confirmed by 16S rDNA sequencing. E. faecalis isolates, in particular, were evaluated for virulence attributes such as their biofilm formation potential, and susceptibility to antimicrobials and an antiseptic, chlorhexidine gluconate. A total of 40 individuals (16.6%) and 10% children, 4% adolescents, 14% young adults, 30% adults, and 25% elderly carried oral enterococci. The oral enterococcal burden in adolescents was significantly lower than in the adults (p = 0.000) and elderly (p = 0.004). The proportion of carriers was higher among females (p = 0.001). E. faecalis was the most frequent isolate in all the age groups (p = 0.000), followed by E. durans and E. faecium. Whilst all the clinical isolates were able to form biofilms, only a proportion of them were able to produce lipase (92%), hemolysin (38%), and gelatinase (39%). Of all the isolates 53.8% were resistant to tetracycline, 12.3% to amoxicillin, 16.0% to ampicillin, 20.8% to chloramphenicol and 43.4% to erythromycin. None of the isolates were resistant to vancomycin. Our data suggest that in this Brazilian cohort the oral cavity may act as a significant reservoir of rather virulent and antibiotic resistant enterococci, with an increasing degree of carriage in the adults and elderly. Hence clinicians should be cognizant of this silent reservoir of virulent enterococci that may pose a particular threat of nosocomial infection. PMID

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

    PubMed Central

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

    2015-01-01

    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. PMID:25918441

  19. DNA microarray detection of antimicrobial resistance genes in Detection and Characterization of Antibiotic Resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Detection of antimicrobial resistance genes is essential for research and an important tool for clinical diagnostics. Most techniques used to identify resistance genes can only detect one or a few genes per assay, whereas DNA microarray technology can detect thousands of genes in a single assay. Sev...

  20. Epidemiology, ecology, and molecular genetics of antimicrobial resistance in pathogenic and commensal bacteria from food animals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The National Antimicrobial Resistance Monitoring System (NARMS) is a collaborative program between the Food and Drug Administration (FDA), the Centers for Disease Control (CDC), and the United States Department of Agriculture to prospectively monitor changes in antimicrobial susceptibilities of zoon...

  1. How could preventive therapy affect the prevalence of drug resistance? Causes and consequences

    PubMed Central

    Kunkel, Amber; Colijn, Caroline; Lipsitch, Marc; Cohen, Ted

    2015-01-01

    Various forms of preventive and prophylactic antimicrobial therapies have been proposed to combat HIV (e.g. pre-exposure prophylaxis), tuberculosis (e.g. isoniazid preventive therapy) and malaria (e.g. intermittent preventive treatment). However, the potential population-level effects of preventative therapy (PT) on the prevalence of drug resistance are not well understood. PT can directly affect the rate at which resistance is acquired among those receiving PT. It can also indirectly affect resistance by altering the rate at which resistance is acquired through treatment for active disease and by modifying the level of competition between transmission of drug-resistant and drug-sensitive pathogens. We propose a general mathematical model to explore the ways in which PT can affect the long-term prevalence of drug resistance. Depending on the relative contributions of these three mechanisms, we find that increasing the level of coverage of PT may result in increases, decreases or non-monotonic changes in the overall prevalence of drug resistance. These results demonstrate the complexity of the relationship between PT and drug resistance in the population. Care should be taken when predicting population-level changes in drug resistance from small pilot studies of PT or estimates based solely on its direct effects. PMID:25918446

  2. How could preventive therapy affect the prevalence of drug resistance? Causes and consequences.

    PubMed

    Kunkel, Amber; Colijn, Caroline; Lipsitch, Marc; Cohen, Ted

    2015-06-01

    Various forms of preventive and prophylactic antimicrobial therapies have been proposed to combat HIV (e.g. pre-exposure prophylaxis), tuberculosis (e.g. isoniazid preventive therapy) and malaria (e.g. intermittent preventive treatment). However, the potential population-level effects of preventative therapy (PT) on the prevalence of drug resistance are not well understood. PT can directly affect the rate at which resistance is acquired among those receiving PT. It can also indirectly affect resistance by altering the rate at which resistance is acquired through treatment for active disease and by modifying the level of competition between transmission of drug-resistant and drug-sensitive pathogens. We propose a general mathematical model to explore the ways in which PT can affect the long-term prevalence of drug resistance. Depending on the relative contributions of these three mechanisms, we find that increasing the level of coverage of PT may result in increases, decreases or non-monotonic changes in the overall prevalence of drug resistance. These results demonstrate the complexity of the relationship between PT and drug resistance in the population. Care should be taken when predicting population-level changes in drug resistance from small pilot studies of PT or estimates based solely on its direct effects.

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

    PubMed

    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. Prevalence of antibiotic susceptibility and resistance of Escherichia coli in acute uncomplicated cystitis in Korea

    PubMed Central

    Kim, Jae Heon; Sun, Hwa Yeon; Kim, Tae Hyong; Shim, Sung Ryul; Doo, Seung Whan; Yang, Won Jae; Lee, Eun Jung; Song, Yun Seob

    2016-01-01

    Abstract Background: The aim of this study is to determine the prevalence of antibiotic susceptibility and resistance of Escherichia coli Escherichia coli (E coli) in female uncomplicated cystitis in Korea using meta-analysis. Methods: A cross-search of the literature was performed with MEDLINE for all relevant data published before October 2015 and EMBASE from 1980 to 2015, the Cochrane Library, KoreaMed, RISS, KISS, and DBPia were also searched. Observational or prospective studies that reported the prevalence of antimicrobial susceptibility and resistance of E coli were selected for inclusion. No language or time restrictions were applied. We performed a meta-analysis using a random effects model to quantify the prevalence of antimicrobial susceptibility and resistance of E coli. Results: Ten studies were eligible for the meta-analysis, which together included a total of 2305 women with uncomplicated cystitis. The overall resistance rate to antibiotics was 0.28 (95% confidence interval [CI]: 0.25, 0.32). The pooled resistance rates were 0.08 (95% CI: 0.06, 0.11) for cephalosporin, 0.22 (95% CI: 0.18, 0.25) for fluoroquinolone (FQ), and 0.43 (95% CI: 0.35, 0.51) for trimethoprim/sulfamethoxazole (TMP/SMX). Regression analysis showed that resistance to FQ is increasing (P = 0.014) and resistance to TMP/SMX is decreasing (P = 0.043) by year. The generation of cephalosporin was not a significant moderator of differences in resistance rate. Conclusion: The resistance rate of FQ in Korea is over 20% and is gradually increasing. Although the resistance rate of TMP/SMX is over 40%, its tendency is in decreasing state. Antibiotic strategies used for the treatment of uncomplicated cystitis in Korea have to be modified. PMID:27603359

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

    PubMed Central

    2014-01-01

    Background 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. Results 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. Conclusions 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

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

    PubMed Central

    Pang, Zhizhao; Qin, Tian; Ren, Hongyu; Pan, Zhuo; Zhou, Jikun

    2016-01-01

    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

  7. Australian Group on Antimicrobial Resistance Hospital-onset Staphylococcus aureus Surveillance Programme annual report, 2011.

    PubMed

    Coombs, Geoffrey W; Nimmo, Graeme R; Pearson, Julie C; Collignon, Peter J; Bell, Jan M; McLaws, Mary-Louise; Christiansen, Keryn J; Turnidge, John D

    2013-09-01

    In 2011, the Australian Group on Antimicrobial Resistance (AGAR) conducted a period-prevalence survey of clinical Staphylococcus aureus isolated from hospital inpatients. Twenty-nine microbiology laboratories from all states and mainland territories participated. Specimens were collected more than 48 hours post-admission. Isolates were tested by Vitek2® antimicrobial susceptibility card (AST-P612 card). Nationally, the proportion of S. aureus that were methicillin-resistant S. aureus (MRSA) was 30.3%; ranging from 19.9% in Western Australia to 36.8% in New South Wales/Australian Capital Territory. Resistance to the non-ß-lactam antimicrobials was common except for rifampicin, fusidic acid, high-level mupirocin and daptomycin. No resistance was detected for vancomycin, teicoplanin or linezolid. Antibiotic resistance in methicillin susceptible S. aureus (MSSA) was rare apart from erythromycin (13.2%) and there was no resistance to vancomycin, teicoplanin or linezolid. Inducible clindamycin resistance was the norm for erythromycin resistant, clindamycin intermediate/susceptible S. aureus in Australia with 90.6% of MRSA and 83.1% of MSSA with this phenotype having a positive double disc diffusion test (D-test). The proportion of S. aureus characterised as being healthcare-associated MRSA (HA-MRSA) was 18.2%, ranging from 4.5% in Western Australia to 28.0% in New South Wales/Australian Capital Territory. Four HA-MRSA clones were characterised and 98.8% of HA-MRSA isolates were classified as either ST22-IV [2B] (EMRSA-15) or ST239-III [3A] (Aus-2/3 EMRSA). Multiclonal community-associated MRSA (CA-MRSA) accounted for 11.7% of all S. aureus. In Australia, regional variation in resistance is due to the differential distribution of MRSA clones between regions, particularly for the major HA-MRSA clone, ST239-III [3A] (Aus-2/3 EMRSA), which is resistant to multiple non-ß-lactam antimicrobials. PMID:24890956

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

    PubMed

    Guo, Yumei; Zhou, Haijian; Qin, Liyun; Pang, Zhizhao; Qin, Tian; Ren, Hongyu; Pan, Zhuo; Zhou, Jikun

    2016-01-01

    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

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

    PubMed Central

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

    2013-01-01

    Antimicrobial drug administration to household livestock may put humans and animals at risk for acquisition of antimicrobial drug–resistant pathogens. To describe animal husbandry practices, including animal healthcare-seeking and antimicrobial drug use in rural Bangladesh, we conducted semi-structured in-depth interviews with key informants, including female household members (n = 79), village doctors (n = 10), and pharmaceutical representatives, veterinarians, and government officials (n = 27), and performed observations at animal health clinics (n = 3). Prevalent animal husbandry practices that may put persons at risk for acquisition of pathogens included shared housing and water for animals and humans, antimicrobial drug use for humans and animals, and crowding. Household members reported seeking human and animal healthcare from unlicensed village doctors rather than formal-sector healthcare providers and cited cost and convenience as reasons. Five times more per household was spent on animal than on human healthcare. Strengthening animal and human disease surveillance systems should be continued. Interventions are recommended to provide vulnerable populations with a means of protecting their livelihood and health. PMID:24062478

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

    PubMed

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

    2006-08-01

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

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

    PubMed

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

    2014-05-14

    The emergence of resistance in food animals has been associated to the consumption of antimicrobials in veterinary medicine. Consequently, monitoring programs have been designed to monitor the occurrence of antimicrobial resistant bacteria. This study analyses the amount of antimicrobial agents used in nine European countries from 2005 to 2011, and compares by univariate analysis the correlations between consumptions of each of the following antimicrobial classes; tetracycline, penicillins, cephalosporins, quinolones and macrolides. An overview of resistance in zoonotic and commensal bacteria in Europe focusing on Salmonella, Escherichia coli, Campylobacter sp. and Enterococcus sp., during the same period of time based on monitoring programs is also assessed. With the exception of cephalosporins, linear regressions showed strong positive associations between the consumption of the four different antimicrobial classes. Substantial differences between countries were observed in the amount of antimicrobials used to produce 1 kg of meat. Moreover, large variations in proportions of resistant bacteria were reported by the different countries, suggesting differences in veterinary practice. Despite the withdrawn of a specific antimicrobial from "on farm" use, persistence over the years of bacteria resistant to this particular antimicrobial agent, was still observed. There were also differences in trends of resistance associated to specific animal species. In order to correlate the use of antimicrobial agents to the presence of resistance, surveillance of antimicrobial consumption by animal species should be established. Subsequently, intervention strategies could be designed to minimize the occurrence of resistance. PMID:24589430

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

    PubMed

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

    2014-05-14

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

  13. Prevalence of Methicillin-Resistant and Methicillin-Susceptible S. Aureusin the Saliva of Health Professionals

    PubMed Central

    de Carvalho, Milton Jorge; Pimenta, Fabiana Cristina; Hayashida, Miyeko; Gir, Elucir; da Silva, Adriana Maria; Barbosa, Caio Parente; da Silva Canini, Silvia Rita Marin; Santiago, Silvana

    2009-01-01

    INTRODUCTION: S. aureus is one of the main agents of nosocomial infection and is sometimes difficult to treat with currently available active antimicrobials. PURPOSE: To analyze the prevalence of methicillin-susceptible S.aureus (MSSA) and methicillin-resistant S. aureus (MRSA) as well as the MRSA antimicrobial susceptibility profile isolated in the saliva of health professionals at a large public education hospital. MATERIALS AND METHODS: The project was approved by the research and ethics committee of the institution under study. Three samples of saliva from 340 health professionals were collected. The saliva analysis used to identify S. aureus was based on mannitol fermentation tests, catalase production, coagulase, DNAse, and lecithinase. In order to detect MRSA, samples were submitted to the disk diffusion test and the oxacillin agar screening test. In order to identify the minimum inhibitory concentration, the Etest® technique was used. RESULTS: The prevalence of MSSA was 43.5% (148/340), and MRSA was 4.1% (14/340). MRSA detected by the diffusion disk test, was 100% resistant to penicillin and oxacillin, 92.9% resistant to erythromycin, 57.1% resistant to clindamycin, 42.9% resistant to ciprofloxacin and 57.1% resistant to cefoxetin. CONCLUSION: This subject is important for both the education of health professionals and for preventative measures. Standard and contact-precautions should be employed in professional practice. PMID:19488585

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

    PubMed

    Kooi, Cora; Sokol, Pamela A

    2009-09-01

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

  15. Salmonella prevalence and antimicrobial susceptibility among dairy farm environmental samples collected in Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dairy cattle are a reservoir of several Salmonella serovars that are leading causes of human salmonellosis. The objectives of this study were to determine the environmental prevalence of Salmonella on dairy farms in Texas and to characterize the antimicrobial susceptibility of the isolates. Eleven...

  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.

    PubMed

    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.

  17. Counts, serovars, and antimicrobial resistance phenotypes of Salmonella on raw chicken meat at retail in Colombia.

    PubMed

    Donado-Godoy, Pilar; Clavijo, Viviana; León, Maribel; Arevalo, Alejandra; Castellanos, Ricardo; Bernal, Johan; Tafur, Mc Allister; Ovalle, Maria Victoria; Alali, Walid Q; Hume, Michael; Romero-Zuñiga, Juan Jose; Walls, Isabel; Doyle, Michael P

    2014-02-01

    The objective of this study was to determine Salmonella counts, serovars, and antimicrobial-resistant phenotypes on retail raw chicken carcasses in Colombia. A total of 301 chicken carcasses were collected from six departments (one city per department) in Colombia. Samples were analyzed for Salmonella counts using the most-probable-number method as recommended by the U.S. Department of Agriculture, Food Safety Inspection Service protocol. A total of 378 isolates (268 from our previous study) were serotyped and tested for antimicrobial susceptibility. The overall Salmonella count (mean log most probable number per carcass ± 95% confidence interval) and prevalence were 2.1 (2.0 to 2.3) and 37%, respectively. There were significant differences (P < 0.05) by Salmonella levels (i.e., counts and prevalence) by storage temperature (i.e., frozen, chilled, or ambient), retail store type (wet markets, supermarkets, and independent markets), and poultry company (chicken produced by integrated or nonintegrated company). Frozen chicken had the lowest Salmonella levels compared with chicken stored at other temperatures, chickens from wet markets had higher levels than those from other retail store types, and chicken produced by integrated companies had lower levels than nonintegrated companies. Thirty-one Salmonella serovars were identified among 378 isolates, with Salmonella Paratyphi B tartrate-positive (i.e., Salmonella Paratyphi B dT+) the most prevalent (44.7%), followed by Heidelberg (19%), Enteritidis (17.7%), Typhimurium (5.3%), and Anatum (2.1%). Of all the Salmonella isolates, 35.2% were resistant to 1 to 5 antimicrobial agents, 24.6% to 6 to 10, and 33.9% to 11 to 15. Among all the serovars obtained, Salmonella Paratyphi B dT+ and Salmonella Heidelberg were the most antimicrobial resistant. Salmonella prevalence was determined to be high, whereas cell numbers were relatively low. These data can be used in developing risk assessment models for preventing the

  18. Counts, serovars, and antimicrobial resistance phenotypes of Salmonella on raw chicken meat at retail in Colombia.

    PubMed

    Donado-Godoy, Pilar; Clavijo, Viviana; León, Maribel; Arevalo, Alejandra; Castellanos, Ricardo; Bernal, Johan; Tafur, Mc Allister; Ovalle, Maria Victoria; Alali, Walid Q; Hume, Michael; Romero-Zuñiga, Juan Jose; Walls, Isabel; Doyle, Michael P

    2014-02-01

    The objective of this study was to determine Salmonella counts, serovars, and antimicrobial-resistant phenotypes on retail raw chicken carcasses in Colombia. A total of 301 chicken carcasses were collected from six departments (one city per department) in Colombia. Samples were analyzed for Salmonella counts using the most-probable-number method as recommended by the U.S. Department of Agriculture, Food Safety Inspection Service protocol. A total of 378 isolates (268 from our previous study) were serotyped and tested for antimicrobial susceptibility. The overall Salmonella count (mean log most probable number per carcass ± 95% confidence interval) and prevalence were 2.1 (2.0 to 2.3) and 37%, respectively. There were significant differences (P < 0.05) by Salmonella levels (i.e., counts and prevalence) by storage temperature (i.e., frozen, chilled, or ambient), retail store type (wet markets, supermarkets, and independent markets), and poultry company (chicken produced by integrated or nonintegrated company). Frozen chicken had the lowest Salmonella levels compared with chicken stored at other temperatures, chickens from wet markets had higher levels than those from other retail store types, and chicken produced by integrated companies had lower levels than nonintegrated companies. Thirty-one Salmonella serovars were identified among 378 isolates, with Salmonella Paratyphi B tartrate-positive (i.e., Salmonella Paratyphi B dT+) the most prevalent (44.7%), followed by Heidelberg (19%), Enteritidis (17.7%), Typhimurium (5.3%), and Anatum (2.1%). Of all the Salmonella isolates, 35.2% were resistant to 1 to 5 antimicrobial agents, 24.6% to 6 to 10, and 33.9% to 11 to 15. Among all the serovars obtained, Salmonella Paratyphi B dT+ and Salmonella Heidelberg were the most antimicrobial resistant. Salmonella prevalence was determined to be high, whereas cell numbers were relatively low. These data can be used in developing risk assessment models for preventing the

  19. Food animal-associated Salmonella challenges: pathogenicity and antimicrobial resistance.

    PubMed

    Foley, S L; Lynne, A M

    2008-04-01

    Salmonellosis is a worldwide health problem; Salmonella infections are the second leading cause of bacterial foodborne illness in the United States. Approximately 95% of cases of human salmonellosis are associated with the consumption of contaminated products such as meat, poultry, eggs, milk, seafood, and fresh produce. Salmonella can cause a number of different disease syndromes including gastroenteritis, bacteremia, and typhoid fever, with the most common being gastroenteritis, which is often characterized by abdominal pain, nausea, vomiting, diarrhea, and headache. Typically the disease is self-limiting; however, with more severe manifestations such as bacteremia, antimicrobial therapy is often administered to treat the infection. Currently, there are over 2,500 identified serotypes of Salmonella. A smaller number of these serotypes are significantly associated with animal and human disease including Typhimurium, Enteritidis, Newport, Heidelberg, and Montevideo. Increasingly, isolates from these serotypes are being detected that demonstrate resistance to multiple antimicrobial agents, including third-generation cephalosporins, which are recommended for the treatment of severe infections. Many of the genes that encode resistance are located on transmissible elements such as plasmids that allow for potential transfer of resistance among strains. Plasmids are also known to harbor virulence factors that contribute to Salmonella pathogenicity. Several serotypes of medical importance, including Typhimurium, Enteritidis, Newport, Dublin, and Choleraesuis, are known to harbor virulence plasmids containing genes that code for fimbriae, serum resistance, and other factors. Additionally, many Salmonella contain pathogenicity islands scattered throughout their genomes that encode factors essential for bacterial adhesion, invasion, and infection. Salmonella have evolved several virulence and antimicrobial resistance mechanisms that allow for continued challenges to our

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

    PubMed

    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.

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

    PubMed

    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. PMID:26076416

  2. Transcriptome Profiling of Antimicrobial Resistance in Pseudomonas aeruginosa.

    PubMed

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

    2016-08-01

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

  3. Transcriptome Profiling of Antimicrobial Resistance in Pseudomonas aeruginosa.

    PubMed

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

    2016-08-01

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

  4. Effect of Tulathromycin on Colonization Resistance, Antimicrobial Resistance, and Virulence of Human Gut Microbiota in Chemostats

    PubMed Central

    Hao, Haihong; Zhou, Shengxi; Cheng, Guyue; Dai, Menghong; Wang, Xu; Liu, Zhenli; Wang, Yulian; Yuan, Zonghui

    2016-01-01

    To evaluate microbiological safety of tulathromycin on human intestinal bacteria, tulathromycin (0, 0.1, 1, 10, and 100 μg/mL) was added into Chemostats. Before and after drug exposure, we monitored (1) population, SCFA products, antimicrobial resistance, and colonization resistance of gut microbiota, and (2) the antimicrobial resistance genes, transferability, virulent genes, pathogenicity of Enterococus faecalis. Results showed that low level of tulathromycin did not exhibit microbiological hazard on resistance selection and colonization resistance. However, high level of tulathromycin (10 and 100 μg/mL) may disturb colonization resistance of human gut microbiota and select antimicrobial resistant E. faecalis. Most of the selected resistant E. faecalis carried resistant gene of ermB, transferable element of Tn1545 and three virulence genes (esp, cylA, and ace). One of them (E. faecalis 143) was confirmed to have higher horizontal transfer risk and higher pathogenicity. The calculated no observable adverse effect concentration (NOAEC) and microbiological acceptable daily intake (mADI) in our study was 1 μg/mL and 14.66 μg/kg.bw/day, respectively. PMID:27092131

  5. MRSA in Africa: Filling the Global Map of Antimicrobial Resistance

    PubMed Central

    Falagas, Matthew E.; Karageorgopoulos, Drosos E.; Leptidis, John; Korbila, Ioanna P.

    2013-01-01

    We sought to assess the prevalence of methicillin-resistance among Staphylococcus aureus isolates in Africa. We included articles published in 2005 or later reporting for the prevalence of MRSA among S. aureus clinical isolates. Thirty-two studies were included. In Tunisia, the prevalence of MRSA increased from 16% to 41% between 2002–2007, while in Libya it was 31% in 2007. In South Africa, the prevalence decreased from 36% in 2006 to 24% during 2007–2011. In Botswana, the prevalence varied from 23–44% between 2000–2007. In Algeria and Egypt, the prevalence was 45% and 52% between 2003–2005, respectively. In Nigeria, the prevalence was greater in the northern than the southern part. In Ethiopia and the Ivory Coast, the prevalence was 55% and 39%, respectively. The prevalence of MRSA was lower than 50% in most of the African countries, although it appears to have risen since 2000 in many African countries, except for South Africa. PMID:23922652

  6. Antimicrobial-resistant Escherichia coli in public beach waters in Quebec

    PubMed Central

    Turgeon, Patricia; Michel, Pascal; Levallois, Patrick; Chevalier, Pierre; Daignault, Danielle; Crago, Bryanne; Irwin, Rebecca; McEwen, Scott A; Neumann, Norman F; Louie, Marie

    2012-01-01

    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. OBJECTIVE: To describe the occurrence of antimicrobial-resistant E coli in the recreational waters of beaches in southern Quebec. METHODS: Sampling occurred over two summers; in 2004, 674 water samples were taken from 201 beaches, and in 2005, 628 water samples were taken from 177 beaches. The minimum inhibitory concentrations of the antimicrobial-resistant E coli isolates against a panel of 16 antimicrobials were determined using microbroth dilution. RESULTS: For 2004 and 2005, respectively, 28% and 38% of beaches sampled had at least one water sample contaminated by E coli resistant to one or more antimicrobials, and more than 10% of the resistant isolates were resistant to at least one antimicrobial of clinical importance for human medicine. The three antimicrobials with the highest frequency of resistance were tetracycline, ampicillin and sulfamethoxazole. DISCUSSION: The recreational waters of these beaches represent a potential source of antimicrobial-resistant bacteria for people engaging in water activities. Investigations relating the significance of these findings to public health should be pursued. PMID:23730315

  7. Inappropriate use of antibiotics in hospitals: the complex relationship between antibiotic use and antimicrobial resistance.

    PubMed

    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.

  8. Inappropriate use of antibiotics in hospitals: the complex relationship between antibiotic use and antimicrobial resistance.

    PubMed

    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. PMID:24129283

  9. Australian Group on Antimicrobial Resistance Community-onset Gram-negative Surveillance Program annual report, 2010.

    PubMed

    Turnidge, John D; Gottlieb, Thomas; Mitchell, David H; Coombs, Geoffrey W; Pearson, Julie C; Bell, Jan M

    2013-09-30

    The Australian Group on Antimicrobial Resistance (AGAR) performs regular period-prevalence studies to monitor changes in antimicrobial resistance in selected enteric Gram-negative pathogens. The 2010 survey focussed on community-onset infections, examining isolates from urinary tract infections from patients presenting to outpatient clinics, emergency departments or to community practitioners. Two thousand and ninety-two Escherichia coli, 578 Klebsiella species and 268 Enterobacter species were tested using a commercial automated method (Vitek 2, BioMérieux) and results were analysed using Clinical and Laboratory Standards Institute breakpoints from January 2012. Of the key resistances, non-susceptibility to the third-generation cephalosporin, ceftriaxone, was found in 3.2% of E. coli and 3.2%-4.0% of Klebsiella spp. Non-susceptibility rates to ciprofloxacin were 5.4% for E. coli, 1.0%-2.3% for Klebsiella spp., and 2.5%-6.6% in Enterobacter spp, and resistance rates to piperacillin-tazobactam were 2.8%, 3.2%-6.9%, and 16.8%-18.0% for the same 3 groups respectively. Only 3 strains, 2 Klebsiella spp. and 1 Enterobacter spp, were shown to harbour a carbapenemase (IMP-4).

  10. Australian Group on Antimicrobial Resistance Community-onset Gram-negative Surveillance Program annual report, 2010.

    PubMed

    Turnidge, John D; Gottlieb, Thomas; Mitchell, David H; Coombs, Geoffrey W; Pearson, Julie C; Bell, Jan M

    2013-09-01

    The Australian Group on Antimicrobial Resistance (AGAR) performs regular period-prevalence studies to monitor changes in antimicrobial resistance in selected enteric Gram-negative pathogens. The 2010 survey focussed on community-onset infections, examining isolates from urinary tract infections from patients presenting to outpatient clinics, emergency departments or to community practitioners. Two thousand and ninety-two Escherichia coli, 578 Klebsiella species and 268 Enterobacter species were tested using a commercial automated method (Vitek 2, BioMérieux) and results were analysed using Clinical and Laboratory Standards Institute breakpoints from January 2012. Of the key resistances, non-susceptibility to the third-generation cephalosporin, ceftriaxone, was found in 3.2% of E. coli and 3.2%-4.0% of Klebsiella spp. Non-susceptibility rates to ciprofloxacin were 5.4% for E. coli, 1.0%-2.3% for Klebsiella spp., and 2.5%-6.6% in Enterobacter spp, and resistance rates to piperacillin-tazobactam were 2.8%, 3.2%-6.9%, and 16.8%-18.0% for the same 3 groups respectively. Only 3 strains, 2 Klebsiella spp. and 1 Enterobacter spp, were shown to harbour a carbapenemase (IMP-4). PMID:24890957

  11. Antimicrobial resistance investigation on Staphylococcus strains in a local hospital in Guangzhou, China, 2001-2010.

    PubMed

    Deng, Yang; Liu, Junyan; Peters, Brian M; Chen, Lei; Miao, Jian; Li, Bing; Li, Lin; Chen, Dingqiang; Yu, Guangchao; Xu, Zhenbo; Shirtliff, Mark E

    2015-02-01

    A retrospective study was conducted on 1,739 Staphylococcus isolates from the First Affiliated Hospital of Jinan University (FAHJU) in Guangzhou during 2001-2010. With the exception of teicoplanin and vancomycin, antimicrobial resistance was commonly observed among the isolates examined, with high resistance rates for β-lactamases (94.0% and 73.7% for penicillin and oxacillin) and resistance percentages for cefoxitin, chloramphenicol, ciprofloxacin, clindamycin, erythromycin, gentamicin, trimethoprim-sulfamethoxazole, and tetracycline ranging from 83.9% to 19.4%. Two hundred sixty-three of the 1,739 isolates were subjected to SCCmec typing and 42 to MLST, spaA, and coa typing. ST239-MRSA-III was prevalently identified along with one distinct coa type HIJKL and 2 spaA types (WGKAOMQ-t037 and WGKAQQ-t030). Class 1 integrons were commonly detected (31.6%), although none of the integron-positive MRSA strains had been isolated since 2009. The widespread detection of integron-based antimicrobial resistance determinants may further contribute to the emergence of superbugs.

  12. Antibiotic-resistant bacteria: prevalence in food and inactivation by food-compatible compounds and plant extracts.

    PubMed

    Friedman, Mendel

    2015-04-22

    Foodborne antibiotic-resistant pathogenic bacteria such as Campylobacter jejuni, Bacillus cereus, Clostridium perfringens, Escherichia coli, Salmonella enterica, Staphylococcus aureus, Vibrio cholerae, and Vibrio parahemolyticus can adversely affect animal and human health, but a better understanding of the factors involved in their pathogenesis is needed. To help meet this need, this overview surveys and interprets much of our current knowledge of antibiotic (multidrug)-resistant bacteria in the food chain and the implications for microbial food safety and animal and human health. Topics covered include the origin and prevalence of resistant bacteria in the food chain (dairy, meat, poultry, seafood, and herbal products, produce, and eggs), their inactivation by different classes of compounds and plant extracts and by the use of chlorine and physicochemical methods (heat, UV light, pulsed electric fields, and high pressure), the synergistic antimicrobial effects of combinations of natural antimicrobials with medicinal antibiotics, and mechanisms of antimicrobial activities and resistant effects. Possible areas for future research are suggested. Plant-derived and other safe natural antimicrobial compounds have the potential to control the prevalence of both susceptible and resistant pathogens in various environments. The collated information and suggested research will hopefully contribute to a better understanding of approaches that could be used to minimize the presence of resistant pathogens in animal feed and human food, thus reducing adverse effects, improving microbial food safety, and helping to prevent or treat animal and human infections.

  13. Sampling Strategies in Antimicrobial Resistance Monitoring: Evaluating How Precision and Sensitivity Vary with the Number of Animals Sampled per Farm

    PubMed Central

    Yamamoto, Takehisa; Hayama, Yoko; Hidano, Arata; Kobayashi, Sota; Muroga, Norihiko; Ishikawa, Kiyoyasu; Ogura, Aki; Tsutsui, Toshiyuki

    2014-01-01

    Because antimicrobial resistance in food-producing animals is a major public health concern, many countries have implemented antimicrobial monitoring systems at a national level. When designing a sampling scheme for antimicrobial resistance monitoring, it is necessary to consider both cost effectiveness and statistical plausibility. In this study, we examined how sampling scheme precision and sensitivity can vary with the number of animals sampled from each farm, while keeping the overall sample size constant to avoid additional sampling costs. Five sampling strategies were investigated. These employed 1, 2, 3, 4 or 6 animal samples per farm, with a total of 12 animals sampled in each strategy. A total of 1,500 Escherichia coli isolates from 300 fattening pigs on 30 farms were tested for resistance against 12 antimicrobials. The performance of each sampling strategy was evaluated by bootstrap resampling from the observational data. In the bootstrapping procedure, farms, animals, and isolates were selected randomly with replacement, and a total of 10,000 replications were conducted. For each antimicrobial, we observed that the standard deviation and 2.5–97.5 percentile interval of resistance prevalence were smallest in the sampling strategy that employed 1 animal per farm. The proportion of bootstrap samples that included at least 1 isolate with resistance was also evaluated as an indicator of the sensitivity of the sampling strategy to previously unidentified antimicrobial resistance. The proportion was greatest with 1 sample per farm and decreased with larger samples per farm. We concluded that when the total number of samples is pre-specified, the most precise and sensitive sampling strategy involves collecting 1 sample per farm. PMID:24466335

  14. Sampling strategies in antimicrobial resistance monitoring: evaluating how precision and sensitivity vary with the number of animals sampled per farm.

    PubMed

    Yamamoto, Takehisa; Hayama, Yoko; Hidano, Arata; Kobayashi, Sota; Muroga, Norihiko; Ishikawa, Kiyoyasu; Ogura, Aki; Tsutsui, Toshiyuki

    2014-01-01

    Because antimicrobial resistance in food-producing animals is a major public health concern, many countries have implemented antimicrobial monitoring systems at a national level. When designing a sampling scheme for antimicrobial resistance monitoring, it is necessary to consider both cost effectiveness and statistical plausibility. In this study, we examined how sampling scheme precision and sensitivity can vary with the number of animals sampled from each farm, while keeping the overall sample size constant to avoid additional sampling costs. Five sampling strategies were investigated. These employed 1, 2, 3, 4 or 6 animal samples per farm, with a total of 12 animals sampled in each strategy. A total of 1,500 Escherichia coli isolates from 300 fattening pigs on 30 farms were tested for resistance against 12 antimicrobials. The performance of each sampling strategy was evaluated by bootstrap resampling from the observational data. In the bootstrapping procedure, farms, animals, and isolates were selected randomly with replacement, and a total of 10,000 replications were conducted. For each antimicrobial, we observed that the standard deviation and 2.5-97.5 percentile interval of resistance prevalence were smallest in the sampling strategy that employed 1 animal per farm. The proportion of bootstrap samples that included at least 1 isolate with resistance was also evaluated as an indicator of the sensitivity of the sampling strategy to previously unidentified antimicrobial resistance. The proportion was greatest with 1 sample per farm and decreased with larger samples per farm. We concluded that when the total number of samples is pre-specified, the most precise and sensitive sampling strategy involves collecting 1 sample per farm.

  15. Characterization of antimicrobial resistance and virulence genotypes of Enterococcus faecalis recovered from a pork processing plant.

    PubMed

    Aslam, Mueen; Diarra, Moussa S; Masson, Luke

    2012-08-01

    The objective of this study was to assess the antimicrobial resistance and virulence genotypes of Enterococcus faecalis isolated from samples obtained from a commercial pork processing plant. A total of 200 samples were randomly obtained from carcasses after bleeding (BC; 50 samples) and pasteurization (PC; 100 samples) and from retail pork products (RP; 50 samples). One isolate from each E. faecalis -positive sample was analyzed for antimicrobial susceptibility and characterized using a enterococcal microarray for analysis of resistance and virulence genes. E. faecalis was isolated from 79.5% of BC samples, 2% of PC samples, and 72.7% of RP samples. Resistance to the clinically important drugs ciprofloxacin (one isolate each from BC and RP samples) and daptomycin (one isolate each from PC and RP samples) was found. Multiresistance (to five or more antimicrobials) was more common in E. faecalis isolates from BC (77.4% of isolates) samples than those from PC (25%) and RP (37.6%) samples. Resistance to kanamycin (43.5%) and streptomycin (69.2%) was noted mostly in E. faecalis from BC samples. The most common resistance genes (>5% prevalence) found in E. faecalis were those for aminoglycosides (aac(6), aphA3, and aadE), macrolides-lincosamide (ermB, ermA, sat(4), and linB), and tetracyclines (tetL, tetM, and tetO ). The virulence genes expressing adhesion (ace, efaAfs, and agrBfs), gelatinase (gelE), and pheromone (cAM, ccF10, cob, and cpd1) factors were found in the majority of isolates. Significant associations were found between resistance and virulence genes, suggesting their possible relationship. These data suggest that carcasses entering the final product processing area are mostly free of E. faecalis but are recontaminated with antimicrobial-resistant strains during processing. The source of these contaminants remains to be identified; however, these results underscore the importance of E. faecalis as a reservoir of resistance and virulence genes.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  17. Antimicrobial resistance of major foodborne pathogens from major meat products.

    PubMed

    Gousia, Panagiota; Economou, Vagelis; Sakkas, Hercules; Leveidiotou, Stamatina; Papadopoulou, Chrissanthy

    2011-01-01

    The bacterial contamination of raw and processed meat products with resistant pathogens was studied. The raw samples included sheep (40), goat (40), pork (120), beef (80), and chicken (19) meat, and the processed samples included turkey filets (33), salami (8), readymade mincemeat (16), stuffing (22), and roast-beef (50). The samples were collected from retail shops in Northwestern Greece over a period of 3 years. The isolated pathogens were evaluated for susceptibilities to 19 antimicrobial agents used in humans. Out of 428 samples, 157 strains of Escherichia coli, 25 of Yersinia enterocolitica, 57 of Staphylococcus aureus, 57 of Enterococcus spp., 4 of Salmonella spp., and 3 of Campylobacter jejuni were isolated. Among the isolates 14.6% of the E. coli, 10.5% of S. aureus, 4% of Y. enterocolitica, 25% of Salmonella spp., and 42.1% of Enterococcus spp. were susceptible to antibiotics. E. coli from chicken exhibited high rates of resistance to ciprofloxacin (62.5%) followed by lamb/goat (10.9%), pork (15.7%), and beef (27.9%) meat. Resistance to nitrofurantoin dominated in the lamb/goat isolates (60%). Resistance to tetracycline predominated in pork (68.2%) and chicken (62.5%), and resistance to aminoglycosides dominated in lamb/goat meat isolates. S. aureus resistance to clindamycin predominated in lamb/goat isolates (50%), whereas resistance to ciprofloxacin predominated in the pork strains, but no resistance to methicillin was observed. Of the enterococci isolates 21.1% were resistant to vancomycin. High resistance to ampicillin (96%) was observed in Y. enterocolitica and all of the C. jejuni isolates were resistant to ampicillin, cephalothin, and cefuroxime. These results indicate that meat can be a source of resistant bacteria, which could potentially be spread to the community through the food chain. PMID:21039131

  18. Enteric pathogens and antimicrobial resistance in turkey vultures (Cathartes aura) feeding at the wildlife-livestock interface.

    PubMed

    Sulzner, Kate; Kelly, Terra; Smith, Woutrina; Johnson, Christine K

    2014-12-01

    Free-flying turkey vultures (Cathartes aura) were sampled in California to investigate the fecal shedding prevalence and antimicrobial susceptibility of Salmonella enterica, Campylobacter spp., and Escherichia coli. Nine different serotypes of Salmonella enterica were detected in cloacal swabs from turkey vultures, and 6% of vultures were shedding Campylobacter spp.. Turkey vultures sampled at a location with range sheep were more likely to shed tetracycline-resistant E. coli, suggesting that proximity to livestock facilities could facilitate acquisition of drug-resistant bacteria in avian scavengers. These findings illustrate the importance of assessing drug-resistant pathogen transfer at the livestock-wildlife interface. PMID:25632686

  19. Enteric pathogens and antimicrobial resistance in turkey vultures (Cathartes aura) feeding at the wildlife-livestock interface.

    PubMed

    Sulzner, Kate; Kelly, Terra; Smith, Woutrina; Johnson, Christine K

    2014-12-01

    Free-flying turkey vultures (Cathartes aura) were sampled in California to investigate the fecal shedding prevalence and antimicrobial susceptibility of Salmonella enterica, Campylobacter spp., and Escherichia coli. Nine different serotypes of Salmonella enterica were detected in cloacal swabs from turkey vultures, and 6% of vultures were shedding Campylobacter spp.. Turkey vultures sampled at a location with range sheep were more likely to shed tetracycline-resistant E. coli, suggesting that proximity to livestock facilities could facilitate acquisition of drug-resistant bacteria in avian scavengers. These findings illustrate the importance of assessing drug-resistant pathogen transfer at the livestock-wildlife interface.

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

    MedlinePlus

    ... NIAID invests in basic research to understand the biology of microbes, their behavior, and how drug resistance ... Nucleotide Polymorphism Phylogenetics & Ontology Proteomics & Protein Analysis Systems Biology Data Portals Software Applications BCBB Mobyle Interface Designer ( ...

  1. Apparent and true resistant hypertension: definition, prevalence and outcomes.

    PubMed

    Judd, E; Calhoun, D A

    2014-08-01

    Resistant hypertension, defined as blood pressure (BP) remaining above goal despite the use of > or =3 antihypertensive medications at maximally tolerated doses (one ideally being a diuretic) or BP that requires > or =4 agents to achieve control, has received more attention with increased efforts to improve BP control rates and the emergence of device-based therapies for hypertension. This classically defined resistant group consists of patients with true resistant hypertension, controlled resistant hypertension and pseudo-resistant hypertension. In studies where pseudo-resistant hypertension cannot be excluded (for example, 24-h ambulatory BP not obtained), the term apparent resistant hypertension has been used to identify 'apparent' lack of control on > or =3 medications. Large, well-designed studies have recently reported the prevalence of resistant hypertension. Pooling prevalence data from these studies and others within North America and Europe with a combined sample size of >600,000 hypertensive participants, the prevalence of resistant hypertension is 14.8% of treated hypertensive patients and 12.5% of all hypertensives. However, the prevalence of true resistant hypertension, defined as uncontrolled both by office and 24-h ambulatory BP monitoring with confirmed medication adherence, may be more meaningful in terms of identifying risk and estimating benefit from newer therapies like renal denervation. Rates of cardiovascular events and mortality follow mean 24-h ambulatory BPs in patients with resistant hypertension, and true resistant hypertension represents the highest risk. The prevalence of true resistant hypertension has not been directly measured in large trials; however, combined data from smaller studies suggest that true resistant hypertension is present in half of the patients with resistant hypertension who are uncontrolled in the office. Our pooled analysis shows prevalence rates of 10.1% and 7.9% for uncontrolled resistant hypertension among

  2. Erythromycin resistance genes in group A streptococci in Finland. The Finnish Study Group for Antimicrobial Resistance.

    PubMed

    Kataja, J; Huovinen, P; Skurnik, M; Seppälä, H

    1999-01-01

    Streptococcus pyogenes isolates (group A streptococcus) of different erythromycin resistance phenotypes were collected from all over Finland in 1994 and 1995 and studied; they were evaluated for their susceptibilities to 14 antimicrobial agents (396 isolates) and the presence of different erythromycin resistance genes (45 isolates). The erythromycin-resistant isolates with the macrolide-resistant but lincosamide- and streptogramin B-susceptible phenotype (M phenotype) were further studied for their plasmid contents and the transferability of resistance genes. Resistance to antimicrobial agents other than macrolides, clindamycin, tetracycline, and chloramphenicol was not found. When compared to our previous study performed in 1990, the rate of resistance to tetracycline increased from 10 to 93% among isolates with the inducible resistance (IR) phenotype of macrolide, lincosamide, and streptogramin B (MLSB) resistance. Tetracycline resistance was also found among 75% of the MLSB-resistant isolates with the constitutive resistance (CR) phenotype. Resistance to chloramphenicol was found for the first time in S. pyogenes in Finland; 3% of the isolates with the IR phenotype were resistant. All the chloramphenicol-resistant isolates were also resistant to tetracycline. Detection of erythromycin resistance genes by PCR indicated that, with the exception of one isolate with the CR phenotype, all M-phenotype isolates had the macrolide efflux (mefA) gene and all the MLSB-resistant isolates had the erythromycin resistance methylase (ermTR) gene; the isolate with the CR phenotype contained the ermB gene. No plasmid DNA could be isolated from the M-phenotype isolates, but the mefA gene was transferred by conjugation.

  3. Antimicrobial Resistance and Genotypic Diversity of Campylobacter Isolated from Pigs, Dairy, and Beef Cattle in Tanzania

    PubMed Central

    Kashoma, Isaac P.; Kassem, Issmat I.; Kumar, Anand; Kessy, Beda M.; Gebreyes, Wondwossen; Kazwala, Rudovick R.; Rajashekara, Gireesh

    2015-01-01

    Foodborne Campylobacter infections pose a serious threat to public health worldwide. However, the occurrence and characteristics of Campylobacter in food animals and products remain largely unknown in Tanzania. The objective of this study was to determine the prevalence, antibiotic resistance, and genetic profiles (sequence types, STs) of Campylobacter isolated from feces of pigs and dairy and beef cattle in Tanzania. Overall, 259 (~30%) of 864 samples were positive for Campylobacter spp, which were detected in 32.5, 35.4, and 19.6% of the pig, dairy, and beef cattle samples, respectively. Multiplex PCR analysis identified 64.5 and 29.3% of the Campylobacter isolates as C. coli and C. jejuni, respectively. The majority (91.9%) of the isolates from pig samples were identified as C. coli, while C. jejuni accounted for 65.5% of the isolates from cattle. Antimicrobial susceptibility testing using the disk diffusion assay and the broth microdilution method revealed resistance to: ampicillin (Amp) (70.3% and 75.7%, respectively), gentamicin (Gen) (1.8% and 12.6%), streptomycin (Str) (65.8 and 74.8%), erythromycin (Ery) (41.4 and 48.7%), tetracycline (Tet) (18.9 and 23.4%), and ciprofloxacin (Cip) (14.4 and 7.2%). Resistance to nalidixic acid (Nal) (39.6%), azithromycin (Azm) (13.5%), and chloramphenicol (Chl) (4.5%) was determined using the disk diffusion assay only, while resistance to tylosin (Tyl) (38.7%) was quantified using the broth microdilution method. Multilocus sequence typing of 111 Campylobacter isolates resulted in the identification of 48 STs (26 C. jejuni and 22 C. coli) of which seven were novel (six C. jejuni and one C. coli). Taken together, this study revealed the high prevalence, genetic diversity and antimicrobial resistance of Campylobacter in important food animals in Tanzania, which highlights the urgent need for the surveillance and control of Campylobacter in this country. PMID:26617582

  4. Antimicrobial Resistance and Genotypic Diversity of Campylobacter Isolated from Pigs, Dairy, and Beef Cattle in Tanzania.

    PubMed

    Kashoma, Isaac P; Kassem, Issmat I; Kumar, Anand; Kessy, Beda M; Gebreyes, Wondwossen; Kazwala, Rudovick R; Rajashekara, Gireesh

    2015-01-01

    Foodborne Campylobacter infections pose a serious threat to public health worldwide. However, the occurrence and characteristics of Campylobacter in food animals and products remain largely unknown in Tanzania. The objective of this study was to determine the prevalence, antibiotic resistance, and genetic profiles (sequence types, STs) of Campylobacter isolated from feces of pigs and dairy and beef cattle in Tanzania. Overall, 259 (~30%) of 864 samples were positive for Campylobacter spp, which were detected in 32.5, 35.4, and 19.6% of the pig, dairy, and beef cattle samples, respectively. Multiplex PCR analysis identified 64.5 and 29.3% of the Campylobacter isolates as C. coli and C. jejuni, respectively. The majority (91.9%) of the isolates from pig samples were identified as C. coli, while C. jejuni accounted for 65.5% of the isolates from cattle. Antimicrobial susceptibility testing using the disk diffusion assay and the broth microdilution method revealed resistance to: ampicillin (Amp) (70.3% and 75.7%, respectively), gentamicin (Gen) (1.8% and 12.6%), streptomycin (Str) (65.8 and 74.8%), erythromycin (Ery) (41.4 and 48.7%), tetracycline (Tet) (18.9 and 23.4%), and ciprofloxacin (Cip) (14.4 and 7.2%). Resistance to nalidixic acid (Nal) (39.6%), azithromycin (Azm) (13.5%), and chloramphenicol (Chl) (4.5%) was determined using the disk diffusion assay only, while resistance to tylosin (Tyl) (38.7%) was quantified using the broth microdilution method. Multilocus sequence typing of 111 Campylobacter isolates resulted in the identification of 48 STs (26 C. jejuni and 22 C. coli) of which seven were novel (six C. jejuni and one C. coli). Taken together, this study revealed the high prevalence, genetic diversity and antimicrobial resistance of Campylobacter in important food animals in Tanzania, which highlights the urgent need for the surveillance and control of Campylobacter in this country. PMID:26617582

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

    PubMed

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

    2016-09-01

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

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

    PubMed

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

    2000-07-01

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

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

    PubMed

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

    2000-07-01

    Antimicrobial resistance can make the efficient treatment of bacterial infections in humans and animals more difficult. Antimicrobial use in food animals may be one of the factors contributing to resistance. The Spanish surveillance network VAV has established a baseline of antimicrobial resistance in Escherichia coli strains from healthy pigs. Minimum inhibitory concentration and patterns of resistance to antimicrobials used in animals and humans were determined for 205 faecal strains isolated in a sampling frame of four slaughterhouses in Spain from 220 pigs in 1998. Higher levels of resistance were seen against antimicrobial agents authorised for use in food animals especially tetracycline, sulphonamides, trimethoprim and amoxycillin. All isolates were susceptible to antimicrobials employed mainly in humans such as ceftazidime, cefotaxime, imipenem, aztreonam and amikacin. PMID:10854810

  8. Multidrug-resistant organisms, wounds and topical antimicrobial protection.

    PubMed

    Bowler, Philip G; Welsby, Sarah; Towers, Victoria; Booth, Rebecca; Hogarth, Andrea; Rowlands, Victoria; Joseph, Alexis; Jones, Samantha A

    2012-08-01

    Multidrug-resistant organisms (MDROs) are increasingly implicated in both acute and chronic wound infections. The limited therapeutic options are further compromised by the fact that wound bacteria often co-exist within a biofilm community which enhances bacterial tolerance to antibiotics. As a consequence, topical antiseptics may be an important consideration for minimising the opportunity for wound infections involving MDROs. The objective of this research was to investigate the antimicrobial activity of a silver-containing gelling fibre dressing against a variety of MDROs in free-living and biofilm states, using stringent in vitro models designed to simulate a variety of wound conditions. MDROs included Acinetobacter baumannii, community-associated methicillin-resistant Staphylococcus aureus, and extended-spectrum beta-lactamase-producing bacteria. Clostridium difficile was also included in the study because it carries many of the characteristics seen in MDROs and evidence of multidrug resistance is emerging. Sustained in vitro antimicrobial activity of the silver-containing dressing was shown against 10 MDROs in a simulated wound fluid over 7 days, and inhibitory and bactericidal effects against both free-living and biofilm phenotypes were also consistently shown in simulated colonised wound surface models. The in vitro data support consideration of the silver-containing gelling fibre dressing as part of a protocol of care in the management of wounds colonised or infected with MDROs.

  9. Recognition of mechanisms involved in bile resistance important to halting antimicrobial resistance in nontyphoidal Salmonella.

    PubMed

    Tsai, Ming-Han; Wu, Sih-Ru; Lee, Hao-Yuan; Chen, Chyi-Liang; Lin, Tzou-Yien; Huang, Yhu-Chering; Chiu, Cheng-Hsun

    2012-08-01

    Increasing antimicrobial resistance in nontyphoidal Salmonella (NTS) is a global public health problem that complicates antimicrobial therapy. As an enteric pathogen, Salmonella must endure the presence of bile in the intestinal tract during the course of infection. In this study, we sought to identify Salmonella genes necessary for bile resistance and to investigate their association with antimicrobial resistance. Four genes related to bile resistance were identified, namely rfaP, rfbK, dam and tolC. The first three genes are involved in lipopolysaccharide synthesis, and tolC is associated with an efflux pump. Antimicrobial susceptibility testing showed increased susceptibility to polymyxin B and ciprofloxacin in rfaP and tolC mutants of Salmonella, respectively. Genetic analysis of 45 clinical isolates of NTS revealed that all isolates with reduced susceptibility to fluoroquinolones (minimum inhibitory concentration ≥0.125 mg/L) were associated with point mutations in the quinolone resistance-determining regions of the gyrA and parC genes. The efflux pump also played a role, as evidenced by the reduction in fluoroquinolone resistance when the TolC efflux pump was inhibited by Phe-Arg-β-naphthylamide, a competitive efflux pump inhibitor. Based on these results, we conclude that an intact membrane structure and the efflux pump system provide mechanisms enabling NTS to resist bile. Caution should be taken when using ciprofloxacin and polymyxin B to treat Salmonella enteric infection, as resistance to these agents involves the same mechanisms. Addition of an efflux pump inhibitor to fluoroquinolones may be an effective strategy to deal with the increasing resistance in NTS.

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

    PubMed

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

    2015-10-01

    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.

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

    PubMed Central

    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. Trichomonas vaginalis Antimicrobial Drug Resistance in 6 US Cities, STD Surveillance Network, 2009–2010

    PubMed Central

    Augostini, Peter; Asbel, Lenore E.; Bernstein, Kyle T.; Kerani, Roxanne P.; Mettenbrink, Christie J.; Pathela, Preeti; Schwebke, Jane R.; Secor, W. Evan; Workowski, Kimberly A.; Davis, Darlene; Braxton, Jim; Weinstock, Hillard S.

    2012-01-01

    Nitroimidazoles (metronidazole and tinidazole) are the only recommended drugs for treating Trichomonas vaginalis infection, and previous samples that assessed resistance of such isolates have been limited in geographic scope. We assessed the prevalence of in vitro aerobic metronidazole and tinidazole resistance among T. vaginalis isolates from multiple geographic sites in the United States. Swab specimens were obtained from women who underwent routine pelvic examinations at sexually transmitted disease clinics in 6 US cities. Cultured T. vaginalis isolates were tested for nitroimidazole resistance (aerobic minimum lethal concentration [MLC] >50 µg/mL). Of 538 T. vaginalis isolates, 23 (4.3%) exhibited low-level in vitro metronidazole resistance (minimum lethal concentrations 50–100 µg/mL). No isolates exhibited moderate- to high-level metronidazole resistance or tinidazole resistance. Results highlight the possibility that reliance on a single class of antimicrobial drugs for treating T. vaginalis infections may heighten vulnerability to emergence of resistance. Thus, novel treatment options are needed. PMID:22608054

  13. Antimicrobial resistance trends in blood culture positive Salmonella Paratyphi A isolates from Pondicherry, India.

    PubMed

    Menezes, G A; Harish, B N; Khan, M A; Goessens, W; Hays, J P

    2016-01-01

    Enteric fever is a public health problem with the upsurge in the occurrence of Salmonella isolates that are resistant to ciprofloxacin. In this study, a total of 284 blood culture isolates of S. Paratyphi A were investigated. Of these isolates, 281 (98.9%) were nalidixic acid resistant. A high rate (6.3%) of high-level resistance (≥ 4 μg/mL) was found to ciprofloxacin. The isolates with ciprofloxacin minimum inhibitory concentrations (MICs) of ≥ 12 μg/mL had 4 mutations, 2 mutations within the quinolone resistance-determining region of gyrA and 2 mutations also in parC. According to the Clinical Laboratory Standards Institute 2012 MIC breakpoints, 75.0% of isolates were resistant to ciprofloxacin. Finally, 3 major pulsed-field gel electrophoresis patterns were observed among the S. Paratyphi A isolates. The spread of fluoroquinolone resistant S. Paratyphi A necessitates a change toward 'evidence-based' treatment for enteric fever. The research provides a perspective on the increasing prevalence of antimicrobial resistant S. Paratyphi A isolates in this region of India. PMID:27080779

  14. Strategies to potentiate antimicrobial photoinactivation by overcoming resistant phenotypes†

    PubMed Central

    Vera, D. Mariano A.; Haynes, Mark H; Ball, Anthony R.; Dai, D. Tianhong; Astrakas, Christos; Kelso, Michael J; Hamblin, Michael R; Tegos, George P.

    2012-01-01

    Conventional antimicrobial strategies have become increasingly ineffective due to the emergence of multidrug resistance among pathogenic microorganisms. The need to overcome these deficiencies has triggered the exploration of alternative treatments and unconventional approaches towards controlling microbial infections. Photodynamic therapy was originally established as an anti-cancer modality and is currently used in the treatment of age related macular degeneration. The concept of photodynamic inactivation requires cell exposure to light energy, typically wavelengths in the visible region that causes the excitation of photosensitizer molecules either exogenous or endogenous, which results in the production of reactive oxygen species. ROS produce cell inactivation and death through modification of intracellular components. The versatile characteristics of PDT prompted its investigation as an anti-infective discovery platform. Advances in understanding of microbial physiology have shed light on a series of pathways, and phenotypes that serve as putative targets for antimicrobial drug discovery. Investigations of these phenotypic elements in concert with PDT have been reported focused on multidrug efflux systems, biofilms, virulence and pathogenesis determinants. In many instances the results are promising but only preliminary and require further investigation. This review discusses the different antimicrobial PDT strategies and highlights the need for highly informative and comprehensive discovery approaches. PMID:22242675

  15. Serotypes, genotypes and antimicrobial resistance patterns of human diarrhoeagenic Escherichia coli isolates circulating in southeastern China.

    PubMed

    Chen, Y; Chen, X; Zheng, S; Yu, F; Kong, H; Yang, Q; Cui, D; Chen, N; Lou, B; Li, X; Tian, L; Yang, X; Xie, G; Dong, Y; Qin, Z; Han, D; Wang, Y; Zhang, W; Tang, Y-W; Li, L

    2014-01-01

    Diarrhoeagenic Escherichia coli (DEC) infection is a major health problem in developing countries. The prevalence and characteristics of DEC have not been thoroughly investigated in China. Consecutive faecal specimens from outpatients with acute diarrhoea in nine sentinel hospitals in southeastern China were collected from July 2009 to June 2011. Bacterial and viral pathogens were detected by culture and RT-PCR, respectively. DEC isolates were further classified into five pathotypes using multiplex PCR. The O/H serotypes, sequence types (STs) and antimicrobial susceptibility profiles of the DEC isolates were determined. A total of 2466 faecal specimens were collected, from which 347 (14.1%) DEC isolates were isolated. DEC was the dominant bacterial pathogen detected. The DEC isolates included 217 EAEC, 62 ETEC, 52 EPEC, 14 STEC, one EIEC and one EAEC/ETEC. O45 (6.6%) was the predominant serotype. Genotypic analysis revealed that the major genotype was ST complex 10 (87, 25.6%). Isolates belonging to the serogroups or genotypes of O6, O25, O159, ST48, ST218, ST94 and ST1491 were highly susceptible to the majority of antimicrobials. In contrast, isolates belonging to O45, O15, O1, O169, ST38, ST226, ST69, ST31, ST93, ST394 and ST648 were highly resistant to the majority of antimicrobials. DEC accounted for the majority of bacterial pathogens causing acute diarrhoea in southeastern China, and it is therefore necessary to test for all DEC, not only the EHEC O157:H7. Some serogroups or genotypes of DEC were highly resistant to the majority of antimicrobials. DEC surveillance should be emphasized. PMID:23521436

  16. Serotypes, genotypes and antimicrobial resistance patterns of human diarrhoeagenic Escherichia coli isolates circulating in southeastern China.

    PubMed

    Chen, Y; Chen, X; Zheng, S; Yu, F; Kong, H; Yang, Q; Cui, D; Chen, N; Lou, B; Li, X; Tian, L; Yang, X; Xie, G; Dong, Y; Qin, Z; Han, D; Wang, Y; Zhang, W; Tang, Y-W; Li, L

    2014-01-01

    Diarrhoeagenic Escherichia coli (DEC) infection is a major health problem in developing countries. The prevalence and characteristics of DEC have not been thoroughly investigated in China. Consecutive faecal specimens from outpatients with acute diarrhoea in nine sentinel hospitals in southeastern China were collected from July 2009 to June 2011. Bacterial and viral pathogens were detected by culture and RT-PCR, respectively. DEC isolates were further classified into five pathotypes using multiplex PCR. The O/H serotypes, sequence types (STs) and antimicrobial susceptibility profiles of the DEC isolates were determined. A total of 2466 faecal specimens were collected, from which 347 (14.1%) DEC isolates were isolated. DEC was the dominant bacterial pathogen detected. The DEC isolates included 217 EAEC, 62 ETEC, 52 EPEC, 14 STEC, one EIEC and one EAEC/ETEC. O45 (6.6%) was the predominant serotype. Genotypic analysis revealed that the major genotype was ST complex 10 (87, 25.6%). Isolates belonging to the serogroups or genotypes of O6, O25, O159, ST48, ST218, ST94 and ST1491 were highly susceptible to the majority of antimicrobials. In contrast, isolates belonging to O45, O15, O1, O169, ST38, ST226, ST69, ST31, ST93, ST394 and ST648 were highly resistant to the majority of antimicrobials. DEC accounted for the majority of bacterial pathogens causing acute diarrhoea in southeastern China, and it is therefore necessary to test for all DEC, not only the EHEC O157:H7. Some serogroups or genotypes of DEC were highly resistant to the majority of antimicrobials. DEC surveillance should be emphasized.

  17. Frequency, virulence genes and antimicrobial resistance of Listeria spp. isolated from bovine clinical mastitis.

    PubMed

    Jamali, Hossein; Radmehr, Behrad

    2013-11-01

    The aims of this study were to determine the prevalence, characteristics and antimicrobial resistance of Listeria spp. isolated from bovine clinical mastitis in Iran. Listeria spp. were detected in 21/207 bovine mastitic milk samples from dairy farms in Iran, comprising L. monocytogenes (n=17), L. innocua (n=3) and L. ivanovii (n=1). L. monocytogenes isolates were grouped into serogroups '4b, 4d, 4e', '1/2a, 3a', '1/2b, 3b, 7' and '1/2c, 3c'; all harboured inlA, inlC and inlJ virulence genes. Listeria spp. were most frequently resistant to penicillin G (14/21 isolates, 66.7%) and tetracyclines (11/21 isolates, 52.4%).

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

    PubMed

    Roberts, Adam P; Mullany, Peter

    2010-12-01

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

  19. Treatment of Helicobacter pylori infection: Meeting the challenge of antimicrobial resistance

    PubMed Central

    Papastergiou, Vasilios; Georgopoulos, Sotirios D; Karatapanis, Stylianos

    2014-01-01

    Treatment of Helicobacter pylori (H. pylori) infection is paramount for the management of prevalent gastrointestinal disorders including peptic ulcer disease and gastric cancer. Due to the wide increase in prevalence of H. pylori resistance to antibiotics, clarithromycin-based triple therapies are not any more suitable for unconditional empiric use, and should not be recommended, unless local resistance to this antibiotic is low (< 20%). Alternative strategies have been proposed to overcome the issue of increasing clarithromycin resistance, and some of them are already implemented in clinical practice. These comprise: (1) adoption of novel, more effective, empirical treatments: bismuth quadruple, sequential, non-bismuth quadruple (concomitant), dual-concomitant (hybrid), and levofloxacin-based regimens, the latter mainly designated as second-line/rescue options; (2) perspectives for a susceptibility-guided (tailored) therapeutic approach based on culture-free molecular testing methods; and (3) adjunct use of probiotics to improve eradication rates. The present article is aimed to provide a comprehensive overview of current and emerging strategies in the treatment of H. pylori infection, focusing on the challenge of antimicrobial resistance. PMID:25110420

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

    PubMed

    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. PMID:27180309

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

    PubMed

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

    2016-06-01

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

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

    PubMed

    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.

  3. Antimicrobial susceptibility/resistance and genetic characteristics of Neisseria gonorrhoeae isolates from Poland, 2010-2012

    PubMed Central

    2014-01-01

    Background In Poland, gonorrhoea has been a mandatorily reported infection since 1948, however, the reported incidences are likely underestimated. No antimicrobial resistance (AMR) data for Neisseria gonorrhoeae has been internationally reported in nearly four decades, and data concerning genetic characteristics of N. gonorrhoeae are totally lacking. The aims of this study were to investigate the AMR to previously and currently recommended gonorrhoea treatment options, the main genetic resistance determinant (penA) for extended-spectrum cephalosporins (ESCs), and genotypic distribution of N. gonorrhoeae isolates in Poland in 2010-2012. Methods N. gonorrhoeae isolates cultured in 2010 (n = 28), 2011 (n = 92) and 2012 (n = 108) in Warsaw and Bialystok, Poland, were examined using antimicrobial susceptibility testing (Etest), pyrosequencing of penA and N. gonorrhoeae multi-antigen sequence typing (NG-MAST). Results The proportions of N. gonorrhoeae isolates showing resistance were as follows: ciprofloxacin 61%, tetracycline 43%, penicillin G 22%, and azithromycin 8.8%. No isolates resistant to ceftriaxone, cefixime or spectinomycin were found. However, the proportion of isolates with an ESC MIC = 0.125 mg/L, i.e. at the resistance breakpoint, increased significantly from none in 2010 to 9.3% and 19% in 2012 for ceftriaxone and cefixime, respectively. Furthermore, 3.1% of the isolates showed multidrug resistance, i.e., resistance to ciprofloxacin, penicillin G, azithromycin, and decreased susceptibility to cefixime (MIC = 0.125 mg/L). Seventy-six isolates (33%) possessed a penA mosaic allele and 14 isolates (6.1%) contained an A501V/T alteration in penicillin-binding protein 2. NG-MAST ST1407 (n = 58, 25% of isolates) was the most prevalent ST, which significantly increased from 2010 (n = 0) to 2012 (n = 46; 43%). Conclusions In Poland, the diversified gonococcal population displayed a high resistance to most antimicrobials

  4. Increase in antimicrobial resistance in bacteria isolated from stranded marine mammals of the Northwest Atlantic.

    PubMed

    Wallace, Courtney C; Yund, Philip O; Ford, Timothy E; Matassa, Keith A; Bass, Anna L

    2013-06-01

    Studies on marine mammals can inform our understanding of the environmental health of the ocean. To evaluate the potential for changes in antimicrobial resistance, we analyzed a database spanning 2004-2010 that consisted of bacterial isolate identity and antimicrobial sensitivity for stranded pinnipeds in the Northwest Atlantic. Samples (n = 170) from treated animals yielded 310 bacterial isolates representing 24 taxa. We evaluated changes in antimicrobial class resistance from 2004 to 2010 for eight taxa. Escherichia coli displayed a significant increase in resistance to several antimicrobial classes. Other taxa displayed significant increases in resistance to aminoglycosides, and/or fluoroquinolones. In addition, we observed a significant increase in multiple antimicrobial resistance in cultures from untreated animals. These results demonstrate an increase in resistance among common bacterial pathogens of marine mammals over a time span of 6 years. PMID:23636484

  5. 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

    PubMed Central

    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

  6. Isolation, Virulence, and Antimicrobial Resistance of Methicillin-Resistant Staphylococcus aureus (MRSA) and Methicillin Sensitive Staphylococcus aureus (MSSA) Strains from Oklahoma Retail Poultry Meats

    PubMed Central

    Abdalrahman, Lubna S.; Stanley, Adriana; Wells, Harrington; Fakhr, Mohamed K.

    2015-01-01

    Staphylococcus aureus is one the top five pathogens causing domestically acquired foodborne illness in the U.S. Only a few studies are available related to the prevalence of S. aureus and MRSA in the U.S. retail poultry industry. The objectives of this study were to determine the prevalence of S. aureus (MSSA and MRSA) in retail chicken and turkey meats sold in Tulsa, Oklahoma and to characterize the recovered strains for their antimicrobial resistance and possession of toxin genes. A total of 167 (114 chicken and 53 turkey) retail poultry samples were used in this study. The chicken samples included 61 organic samples while the rest of the poultry samples were conventional. The overall prevalence of S. aureus was 57/106 (53.8%) in the conventional poultry samples and 25/61 (41%) in the organic ones. Prevalence in the turkey samples (64.2%) was higher than in the chicken ones (42.1%). Prevalence of S. aureus did not vary much between conventional (43.4%) and organic chicken samples (41%). Two chicken samples 2/114 (1.8%) were positive for MRSA. PFGE identified the two MRSA isolates as belonging to PFGE type USA300 (from conventional chicken) and USA 500 (from organic chicken) which are community acquired CA-MRSA suggesting a human based source of contamination. MLST and spa typing also supported this conclusion. A total of 168 Staphylococcus aureus isolates (101 chicken isolates and 67 turkey isolates) were screened for their antimicrobial susceptibility against 16 antimicrobials and their possession of 18 different toxin genes. Multidrug resistance was higher in the turkey isolates compared to the chicken ones and the percentage of resistance to most of the antimicrobials tested was also higher among the turkey isolates. The hemolysin hla and hld genes, enterotoxins seg and sei, and leucocidins lukE-lukD were more prevalent in the chicken isolates. The PVL gene lukS-lukF was detected only in chicken isolates including the MRSA ones. In conclusion, S. aureus is

  7. Isolation, Virulence, and Antimicrobial Resistance of Methicillin-Resistant Staphylococcus aureus (MRSA) and Methicillin Sensitive Staphylococcus aureus (MSSA) Strains from Oklahoma Retail Poultry Meats.

    PubMed

    Abdalrahman, Lubna S; Stanley, Adriana; Wells, Harrington; Fakhr, Mohamed K

    2015-05-29

    Staphylococcus aureus is one the top five pathogens causing domestically acquired foodborne illness in the U.S. Only a few studies are available related to the prevalence of S. aureus and MRSA in the U.S. retail poultry industry. The objectives of this study were to determine the prevalence of S. aureus (MSSA and MRSA) in retail chicken and turkey meats sold in Tulsa, Oklahoma and to characterize the recovered strains for their antimicrobial resistance and possession of toxin genes. A total of 167 (114 chicken and 53 turkey) retail poultry samples were used in this study. The chicken samples included 61 organic samples while the rest of the poultry samples were conventional. The overall prevalence of S. aureus was 57/106 (53.8%) in the conventional poultry samples and 25/61 (41%) in the organic ones. Prevalence in the turkey samples (64.2%) was higher than in the chicken ones (42.1%). Prevalence of S. aureus did not vary much between conventional (43.4%) and organic chicken samples (41%). Two chicken samples 2/114 (1.8%) were positive for MRSA. PFGE identified the two MRSA isolates as belonging to PFGE type USA300 (from conventional chicken) and USA 500 (from organic chicken) which are community acquired CA-MRSA suggesting a human based source of contamination. MLST and spa typing also supported this conclusion. A total of 168 Staphylococcus aureus isolates (101 chicken isolates and 67 turkey isolates) were screened for their antimicrobial susceptibility against 16 antimicrobials and their possession of 18 different toxin genes. Multidrug resistance was higher in the turkey isolates compared to the chicken ones and the percentage of resistance to most of the antimicrobials tested was also higher among the turkey isolates. The hemolysin hla and hld genes, enterotoxins seg and sei, and leucocidins lukE-lukD were more prevalent in the chicken isolates. The PVL gene lukS-lukF was detected only in chicken isolates including the MRSA ones. In conclusion, S. aureus is

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

    PubMed Central

    Opintan, Japheth A; Newman, Mercy J; Arhin, Reuben E; Donkor, Eric S; Gyansa-Lutterodt, Martha; Mills-Pappoe, William

    2015-01-01

    Global efforts are underway to combat antimicrobial resistance (AMR). A key target in this intervention is surveillance for local and national action. Data on AMR in Ghana are limited, and monitoring of AMR is nonexistent. We sought to generate baseline data on AMR, and to assess the readiness of Ghana in laboratory-based surveillance. Biomedical scientists in laboratories across Ghana with capacity to perform bacteriological culture were selected and trained. In-house standard operating protocols were used to perform microbiological investigations on clinical specimens. Additional microbiological tests and data analyses were performed at a centralized laboratory. Surveillance data were stored and analyzed using WHONET program files. A total of 24 laboratories participated in the training, and 1,598 data sets were included in the final analysis. A majority of the bacterial species were isolated from outpatients (963 isolates; 60.3%). Urine (617 isolates; 38.6%) was the most common clinical specimen cultured, compared to blood (100 isolates; 6.3%). Ten of 18 laboratories performed blood culture. Bacteria isolated included Escherichia coli (27.5%), Pseudomonas spp. (14.0%), Staphylococcus aureus (11.5%), Streptococcus spp. (2.3%), and Salmonella enterica serovar Typhi (0.6%). Most of the isolates were multidrug-resistant, and over 80% of them were extended-spectrum beta-lactamases-producing. Minimum inhibitory concentration levels at 50% and at 90% for ciprofloxacin, ceftriaxone, and amikacin on selected multidrug-resistant bacteria species ranged between 2 µg/mL and >256 µg/mL. A range of clinical bacterial isolates were resistant to important commonly used antimicrobials in the country, necessitating an effective surveillance to continuously monitor AMR in Ghana. With local and international support, Ghana can participate in global AMR surveillance. PMID:26604806

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

    PubMed

    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.

  10. 76 FR 21907 - Draft Action Plan-A Public Health Action Plan To Combat Antimicrobial Resistance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-19

    ... the draft, A Public Health Action Plan to Combat Antimicrobial Resistance (76 FR 14402). Written and... spectrum of AR issues, addressing resistance in a wide range of pathogens (bacteria, viruses, fungi,...

  11. Antimicrobial Resistance in Escherichia coli Isolates from Raccoons (Procyon lotor) in Southern Ontario, Canada

    PubMed Central

    Janecko, Nicol; Allan, Mike; Boerlin, Patrick; Chalmers, Gabhan; Kozak, Gosia; McEwen, Scott A.; Reid-Smith, Richard J.

    2012-01-01

    We conducted a cross-sectional study to determine the prevalence of antimicrobial resistance (AMR) in fecal Escherichia coli isolates from raccoons (Procyon lotor) living in Ontario, Canada. From June to October 2007, we trapped raccoons in three areas: one primarily urban site around Niagara, one primarily rural site north of Guelph, and one at the Toronto Zoo. In addition, we conducted a longitudinal study at the Toronto Zoo site to investigate the temporal dynamics of fecal E. coli and AMR in raccoons. Reduced susceptibility to ≥1 antimicrobial agent was detected in E. coli isolates from 19% of 16 raccoons at the urban site, 17% of 29 raccoons from the rural site, and 42% of 130 samples collected from 59 raccoons at the zoo site. Raccoons from the zoo site were significantly more likely to shed E. coli with reduced susceptibility to ≥1 antimicrobial agent than animals from the rural site (odds ratio [OR], 3.41; 95% confidence interval [CI], 1.17 to 12.09; P = 0.02). Resistance to expanded-spectrum cephalosporins (and the associated blaCMY-2 gene) was detected in two animals from the zoo site and one animal from the rural site. Serotyping and pulsed-field gel electrophoresis analysis show that raccoons on the zoo grounds harbor a diverse assemblage of E. coli, with rapid bacterial turnover within individuals over time. Our study indicates that raccoons may shed resistant bacteria of public health significance and that raccoons have the potential to disseminate these bacteria throughout their environment. PMID:22447599

  12. Changes in bacterial resistance patterns in children with urinary tract infections on antimicrobial prophylaxis at University Hospital in Split

    PubMed Central

    Ilić, Tanja; Gračan, Sanda; Arapović, Adela; Čapkun, Vesna; Šubat-Dežulović, Mirna; Saraga, Marijan

    2011-01-01

    Summary Background We assessed prevalence and resistance of uropathogens on antimicrobial agents (AA) from urine cultures (UC) in children hospitalized with urinary tract infections (UTI) at University Hospital in Split. Material/Methods During the 7-year period, children hospitalized only once with UTI alone were compared to those repeatedly hospitalized, and who received long-term antimicrobial prophylaxis (LTAP), as well as those with associated anomalies of the urinary system (US). Results E. coli was the most frequent isolate (67.7%) with resistance to ampicillin by 69.5%, amoxicillin/clavulonic acid by 3.5%, cephalexin by 6.6%, trimethoprim/sulfamethoxazole (TMP-SMX) by 27.5%, and nitrofurantoin by 0.4%. For other uropathogens, AA resistance rates were the following: 64.3%, 5.8%, 10.5%, 21.3%, and 7.9%. The high or increasing resistance to TMP-SMX is characterized by all uropathogens. Patients with anomalies of US showed a lower prevalence of E. coli and Enterococcus sp., but a higher prevalence of Pseudomonas sp., ESBL-producing E. coli and Klebsiella sp. than those without US anomalies. Repeatedly hospitalized patients showed a lower prevalence of E. coli, but a higher prevalence of Pseudomonas sp. and Klebsiella sp. than patients hospitalized only once. Both groups displayed significantly less resistance of Enterococcus sp. In patients receiving LTAP before hospitalization, E. coli was significantly more resistant to ampicillin, amoxicillin/clavulonic acid and TMP/SMX than in those without LTAP. Conclusions Based on our results, we recommend excluding ampicillin altogether, and reconsideration of further use of TMP-SMX, as well as use of nitrofurantoin, cephalexin and amoxicillin/clavulonic acid for LTAP in our region. PMID:21709628

  13. Influence of housing systems on microbial load and antimicrobial resistance patterns of Escherichia coli isolates from eggs produced for human consumption.

    PubMed

    Alvarez-Fernández, Elena; Domínguez-Rodríguez, Jessica; Capita, Rosa; Alonso-Calleja, Carlos

    2012-05-01

    Microbial counts (aerobic bacteria, psychrotrophs, Enterobacteriaceae, coliforms, Pseudomonas spp., Enterococcus spp., Staphylococcus spp., and molds and yeasts) were obtained for the shells of 240 table eggs in northwestern Spain. Eggs from six sources (40 samples in each) were analyzed: chicken eggs from five different housing systems (conventional battery cages, barn, free range, organic, and domestic breeding) and quail eggs (cages). A total of 120 Escherichia coli strains (20 from each source) were tested by the disk diffusion method for resistance to 12 antimicrobial drugs of veterinary and human health significance. Aerobic plate counts ranged from 1.96 ± 1.0 (barn) to 3.69 ± 0.7 (domestic) log CFU/cm(2). Counts for most microbial groups differed significantly between sources. Eggs from domestic production had the highest contamination loads (P < 0.05) for aerobic bacteria, Enterococcus spp., and molds and yeasts and the highest prevalence of E. coli. Twenty-three E. coli isolates (19.17%) were susceptible to all antimicrobials tested, and 80.83 % were resistant to one (22.50%) or more (58.33%) antimicrobials. The housing system had a significant influence (P < 0.05) on the average resistance per strain, with the highest resistance in conventional cage (2.85) and barn (3.10) systems followed by free range (1.55) and quail (1.95). Eggs from organic (1.00) and domestic (0.75) production systems had the lowest resistance per strain. The highest prevalence of resistance was observed for the groups of antimicrobials more frequently used on poultry farms. Our results suggest that a relationship exists between the prevalence of antimicrobial resistance in E. coli strains and the more frequent use of antimicrobials in conventional (cage, barn, and free range) than in domestic and organic chicken housing systems. Education covering good sanitary practices for handling eggs to avoid cross-contamination or inadequate cooking is needed.

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

    PubMed Central

    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 antimicrob