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Sample records for antibiotic resistant bacteria

  1. Antibiotic-resistant bacteria in drinking water.

    Science.gov (United States)

    Armstrong, J L; Shigeno, D S; Calomiris, J J; Seidler, R J

    1981-08-01

    We analyzed drinking water from seven communities for multiply antibiotic-resistant (MAR) bacteria (bacteria resistant to two or more antibiotics) and screened the MAR bacterial isolates obtained against five antibiotics by replica plating. Overall, 33.9% of 2,653 standard plate count bacteria from treated drinking waters were MAR. Two different raw water supplies for two communities carried MAR standard plate count bacteria at frequencies of 20.4 and 18.6%, whereas 36.7 and 67.8% of the standard plate count populations from sites within the respective distribution systems were MAR. Isolate identification revealed that MAR gram-positive cocci (Staphylococcus) and MAR gram-negative, nonfermentative rods (Pseudomonas, Alcaligenes, Moraxella-like group M, and Acinetobacter) were more common in drinking waters than in untreated source waters. Site-to-site variations in generic types and differences in the incidences of MAR organisms indicated that shedding of MAR bacteria living in pipelines may have contributed to the MAR populations in tap water. We conclude that the treatment of raw water and its subsequent distribution select for standard plate count bacteria exhibiting the MAR phenotype.

  2. Antibiotic resistance of lactic acid bacteria

    Directory of Open Access Journals (Sweden)

    Bulajić Snežana

    2008-01-01

    Full Text Available Knowledge on the antibiotic resistance of lactic acid bacteria is still limited, possibly because of the large numbers of genera and species encountered in this group, as well as variances in their resistance spectra. The EFSA considers antibiotic resistances, especially transferable resistances, an important decision criterion for determining a strain's QPS status. There are no approved standards for the phenotypic or genotypic evaluation of antibiotic resistances in food isolates. Also, the choice of media is problematic, as well as the specification of MIC breakpoint values as a result of the large species variation and the possible resulting variation in MIC values between species and genera. The current investigations in this field showed that we might end up with a range of different species- or genus-specific breakpoint values that may further increase the current complexity. Another problem associated with safety determinations of starter strains is that once a resistance phenotype and an associated resistance determinant have been identified, it becomes difficult to show that this determinant is not transferable, especially if the resistance gene is not located on a plasmid and no standard protocols for showing genetic transfer are available. Encountering those problems, the QPS system should allow leeway for the interpretations of results, especially when these relate to the methodology for resistance phenotype determinations, determinations of MIC breakpoints for certain genera, species, or strains, the nondeterminability of a genetic basis of a resistance phenotype and the transferability of resistance genes.

  3. Environmental and Public Health Implications of Water Reuse: Antibiotics, Antibiotic Resistant Bacteria, and Antibiotic Resistance Genes

    Science.gov (United States)

    Hong, Pei-Ying; Al-Jassim, Nada; Ansari, Mohd Ikram; Mackie, Roderick I.

    2013-01-01

    Water scarcity is a global problem, and is particularly acute in certain regions like Africa, the Middle East, as well as the western states of America. A breakdown on water usage revealed that 70% of freshwater supplies are used for agricultural irrigation. The use of reclaimed water as an alternative water source for agricultural irrigation would greatly alleviate the demand on freshwater sources. This paradigm shift is gaining momentum in several water scarce countries like Saudi Arabia. However, microbial problems associated with reclaimed water may hinder the use of reclaimed water for agricultural irrigation. Of particular concern is that the occurrence of antibiotic residues in the reclaimed water can select for antibiotic resistance genes among the microbial community. Antibiotic resistance genes can be associated with mobile genetic elements, which in turn allow a promiscuous transfer of resistance traits from one bacterium to another. Together with the pathogens that are present in the reclaimed water, antibiotic resistant bacteria can potentially exchange mobile genetic elements to create the “perfect microbial storm”. Given the significance of this issue, a deeper understanding of the occurrence of antibiotics in reclaimed water, and their potential influence on the selection of resistant microorganisms would be essential. In this review paper, we collated literature over the past two decades to determine the occurrence of antibiotics in municipal wastewater and livestock manure. We then discuss how these antibiotic resistant bacteria may impose a potential microbial risk to the environment and public health, and the knowledge gaps that would have to be addressed in future studies. Overall, the collation of the literature in wastewater treatment and agriculture serves to frame and identify potential concerns with respect to antibiotics, antibiotic resistant bacteria, and antibiotic resistance genes in reclaimed water. PMID:27029309

  4. Environmental and Public Health Implications of Water Reuse: Antibiotics, Antibiotic Resistant Bacteria, and Antibiotic Resistance Genes

    KAUST Repository

    Hong, Pei-Ying; Aljassim, Nada I.; Ansari, Mohd Ikram; Mackie, Roderick

    2013-01-01

    Water scarcity is a global problem, and is particularly acute in certain regions like Africa, the Middle East, as well as the western states of America. A breakdown on water usage revealed that 70% of freshwater supplies are used for agricultural irrigation. The use of reclaimed water as an alternative water source for agricultural irrigation would greatly alleviate the demand on freshwater sources. This paradigm shift is gaining momentum in several water scarce countries like Saudi Arabia. However, microbial problems associated with reclaimed water may hinder the use of reclaimed water for agricultural irrigation. Of particular concern is that the occurrence of antibiotic residues in the reclaimed water can select for antibiotic resistance genes among the microbial community. Antibiotic resistance genes can be associated with mobile genetic elements, which in turn allow a promiscuous transfer of resistance traits from one bacterium to another. Together with the pathogens that are present in the reclaimed water, antibiotic resistant bacteria can potentially exchange mobile genetic elements to create the “perfect microbial storm”. Given the significance of this issue, a deeper understanding of the occurrence of antibiotics in reclaimed water, and their potential influence on the selection of resistant microorganisms would be essential. In this review paper, we collated literature over the past two decades to determine the occurrence of antibiotics in municipal wastewater and livestock manure. We then discuss how these antibiotic resistant bacteria may impose a potential microbial risk to the environment and public health, and the knowledge gaps that would have to be addressed in future studies. Overall, the collation of the literature in wastewater treatment and agriculture serves to frame and identify potential concerns with respect to antibiotics, antibiotic resistant bacteria, and antibiotic resistance genes in reclaimed water.

  5. Environmental and Public Health Implications of Water Reuse: Antibiotics, Antibiotic Resistant Bacteria, and Antibiotic Resistance Genes

    Directory of Open Access Journals (Sweden)

    Roderick I. Mackie

    2013-07-01

    Full Text Available Water scarcity is a global problem, and is particularly acute in certain regions like Africa, the Middle East, as well as the western states of America. A breakdown on water usage revealed that 70% of freshwater supplies are used for agricultural irrigation. The use of reclaimed water as an alternative water source for agricultural irrigation would greatly alleviate the demand on freshwater sources. This paradigm shift is gaining momentum in several water scarce countries like Saudi Arabia. However, microbial problems associated with reclaimed water may hinder the use of reclaimed water for agricultural irrigation. Of particular concern is that the occurrence of antibiotic residues in the reclaimed water can select for antibiotic resistance genes among the microbial community. Antibiotic resistance genes can be associated with mobile genetic elements, which in turn allow a promiscuous transfer of resistance traits from one bacterium to another. Together with the pathogens that are present in the reclaimed water, antibiotic resistant bacteria can potentially exchange mobile genetic elements to create the “perfect microbial storm”. Given the significance of this issue, a deeper understanding of the occurrence of antibiotics in reclaimed water, and their potential influence on the selection of resistant microorganisms would be essential. In this review paper, we collated literature over the past two decades to determine the occurrence of antibiotics in municipal wastewater and livestock manure. We then discuss how these antibiotic resistant bacteria may impose a potential microbial risk to the environment and public health, and the knowledge gaps that would have to be addressed in future studies. Overall, the collation of the literature in wastewater treatment and agriculture serves to frame and identify potential concerns with respect to antibiotics, antibiotic resistant bacteria, and antibiotic resistance genes in reclaimed water.

  6. Environmental and Public Health Implications of Water Reuse: Antibiotics, Antibiotic Resistant Bacteria, and Antibiotic Resistance Genes

    KAUST Repository

    Hong, Pei-Ying

    2013-07-31

    Water scarcity is a global problem, and is particularly acute in certain regions like Africa, the Middle East, as well as the western states of America. A breakdown on water usage revealed that 70% of freshwater supplies are used for agricultural irrigation. The use of reclaimed water as an alternative water source for agricultural irrigation would greatly alleviate the demand on freshwater sources. This paradigm shift is gaining momentum in several water scarce countries like Saudi Arabia. However, microbial problems associated with reclaimed water may hinder the use of reclaimed water for agricultural irrigation. Of particular concern is that the occurrence of antibiotic residues in the reclaimed water can select for antibiotic resistance genes among the microbial community. Antibiotic resistance genes can be associated with mobile genetic elements, which in turn allow a promiscuous transfer of resistance traits from one bacterium to another. Together with the pathogens that are present in the reclaimed water, antibiotic resistant bacteria can potentially exchange mobile genetic elements to create the “perfect microbial storm”. Given the significance of this issue, a deeper understanding of the occurrence of antibiotics in reclaimed water, and their potential influence on the selection of resistant microorganisms would be essential. In this review paper, we collated literature over the past two decades to determine the occurrence of antibiotics in municipal wastewater and livestock manure. We then discuss how these antibiotic resistant bacteria may impose a potential microbial risk to the environment and public health, and the knowledge gaps that would have to be addressed in future studies. Overall, the collation of the literature in wastewater treatment and agriculture serves to frame and identify potential concerns with respect to antibiotics, antibiotic resistant bacteria, and antibiotic resistance genes in reclaimed water.

  7. Transfer of antibiotic resistant bacteria from animals to man

    DEFF Research Database (Denmark)

    Wegener, Henrik Caspar; Aarestrup, Frank Møller; Gerner-Smidt, P.

    1999-01-01

    for animals either for therapy or for growth promotion. Antibiotic resistance in zoonotic bacteria constitute a public health hazard, primarily through the increased risk of treatment failures. This paper describes the zoonotic bacteria, salmonella, campylobacter, yersinia and enterohaemorrhagic E. coli (EHEC......Antibiotic resistance develops in zoonotic bacteria in response to antibiotics used in food animals. A close association exists between the amounts of antibiotics used and the levels of resistance observed. The classes of antibiotics routinely used for treatment of human infections are also used......). Infections with these agents do not generally require antibiotic therapy, but in some cases antibiotics are essential to obtain a successful cure. The levels and types of resistance observed in zoonotic bacteria in some countries, especially the increasing levels of fluoroquinolone resistance in salmonella...

  8. Antibiotic-Resistant Enteric Bacteria in Environmental Waters

    OpenAIRE

    Lisa M. Casanova; Mark D. Sobsey

    2016-01-01

    Sources of antibiotic resistant organisms, including concentrated animal feeding operations (CAFOs), may lead to environmental surface and groundwater contamination with resistant enteric bacteria of public health concern. The objective of this research is to determine whether Salmonella, Escherichia coli, Yersinia enterocolitica, and enterococci resistant to clinically relevant antibiotics are present in surface and groundwater sources in two eastern North Carolina counties, Craven and Wayne...

  9. Diversity and antibiotic resistance of uropathogenic bacteria from ...

    African Journals Online (AJOL)

    Background: Urinary tract infections (UTI) are one of the major causes of prescribing and antibiotic consumption. In order to use the best antibiotic treatment for their patients, reliable and recent data about epidemiology and antibiotic resistance profile of uropathogenic bacteria must be available for clinicians. Therefore ...

  10. Mathematical studies on nosocomial spread of antibiotic-resistant bacteria

    NARCIS (Netherlands)

    Gurieva, T.V.

    2017-01-01

    Infections with antibiotic-resistant bacteria are a worldwide problem in hospitals and their rates remain high in many countries despite efforts to reduce the rates. Infection prevention is complicated by asymptomatic carriers. Using mathematical modelling, different intervention strategies were

  11. Fate of antibiotic resistant bacteria and genes during wastewater chlorination: implication for antibiotic resistance control.

    Directory of Open Access Journals (Sweden)

    Qing-Bin Yuan

    Full Text Available This study investigated fates of nine antibiotic-resistant bacteria as well as two series of antibiotic resistance genes in wastewater treated by various doses of chlorine (0, 15, 30, 60, 150 and 300 mg Cl2 min/L. The results indicated that chlorination was effective in inactivating antibiotic-resistant bacteria. Most bacteria were inactivated completely at the lowest dose (15 mg Cl2 min/L. By comparison, sulfadiazine- and erythromycin-resistant bacteria exhibited tolerance to low chlorine dose (up to 60 mg Cl2 min/L. However, quantitative real-time PCRs revealed that chlorination decreased limited erythromycin or tetracycline resistance genes, with the removal levels of overall erythromycin and tetracycline resistance genes at 0.42 ± 0.12 log and 0.10 ± 0.02 log, respectively. About 40% of erythromycin-resistance genes and 80% of tetracycline resistance genes could not be removed by chlorination. Chlorination was considered not effective in controlling antimicrobial resistance. More concern needs to be paid to the potential risk of antibiotic resistance genes in the wastewater after chlorination.

  12. Antibiotic resistance shaping multi-level population biology of bacteria.

    Science.gov (United States)

    Baquero, Fernando; Tedim, Ana P; Coque, Teresa M

    2013-01-01

    Antibiotics have natural functions, mostly involving cell-to-cell signaling networks. The anthropogenic production of antibiotics, and its release in the microbiosphere results in a disturbance of these networks, antibiotic resistance tending to preserve its integrity. The cost of such adaptation is the emergence and dissemination of antibiotic resistance genes, and of all genetic and cellular vehicles in which these genes are located. Selection of the combinations of the different evolutionary units (genes, integrons, transposons, plasmids, cells, communities and microbiomes, hosts) is highly asymmetrical. Each unit of selection is a self-interested entity, exploiting the higher hierarchical unit for its own benefit, but in doing so the higher hierarchical unit might acquire critical traits for its spread because of the exploitation of the lower hierarchical unit. This interactive trade-off shapes the population biology of antibiotic resistance, a composed-complex array of the independent "population biologies." Antibiotics modify the abundance and the interactive field of each of these units. Antibiotics increase the number and evolvability of "clinical" antibiotic resistance genes, but probably also many other genes with different primary functions but with a resistance phenotype present in the environmental resistome. Antibiotics influence the abundance, modularity, and spread of integrons, transposons, and plasmids, mostly acting on structures present before the antibiotic era. Antibiotics enrich particular bacterial lineages and clones and contribute to local clonalization processes. Antibiotics amplify particular genetic exchange communities sharing antibiotic resistance genes and platforms within microbiomes. In particular human or animal hosts, the microbiomic composition might facilitate the interactions between evolutionary units involved in antibiotic resistance. The understanding of antibiotic resistance implies expanding our knowledge on multi

  13. Stalking Antibiotic-Resistant Bacteria in Common Vegetables

    Science.gov (United States)

    Brock, David; Boeke, Caroline; Josowitz, Rebecca; Loya, Katherine

    2004-01-01

    The study developed a simple experimental protocol for studying antibiotic resistant bacteria that will allow students to determine the proportion of such bacteria found on common fruit and vegetable crops. This protocol can open up the world of environmental science and show how human behavior can dramatically alter ecosystems.

  14. Reusing Treated Wastewater: Consideration of the Safety Aspects Associated with Antibiotic-Resistant Bacteria and Antibiotic Resistance Genes

    KAUST Repository

    Hong, Pei-Ying; Julian, Timothy; Pype, Marie-Laure; Jiang, Sunny; Nelson, Kara; Graham, David; Pruden, Amy; Manaia, Cé lia

    2018-01-01

    As more countries engage in water reuse, either intended or de facto, there is an urgent need to more comprehensively evaluate resulting environmental and public health concerns. While antibiotic-resistant bacteria (ARB) and antibiotic resistance

  15. Antibiotic Resistance of Diverse Bacteria from Aquaculture in Borneo

    Directory of Open Access Journals (Sweden)

    M. M. Kathleen

    2016-01-01

    Full Text Available The administration of antimicrobials in aquaculture provides a selective pressure creating a reservoir of multiple resistant bacteria in the cultured fish and shrimps as well as the aquaculture environment. The objective of this study was to determine the extent of antibiotic resistance in aquaculture products and aquaculture’s surrounding environment in Sarawak, Malaysian Borneo. Ninety-four identified bacterial isolates constituted of 17 genera were isolated from sediment, water, and cultured organisms (fish and shrimp in selected aquaculture farms. These isolates were tested for their antibiotic resistance against 22 antibiotics from several groups using the disk diffusion method. The results show that the highest resistance was observed towards streptomycin (85%, n=20, while the lowest resistance was towards gentamicin (1.1%, n=90. The multiple antibiotic resistant (MAR index of the isolates tested ranged between 0 and 0.63. It was suggested that isolates with MAR index > 0.2 were recovered from sources with high risk of antibiotic resistant contamination. This study revealed low level of antibiotic resistance in the aquaculture bacterial isolates except for streptomycin and ampicillin (>50% resistance, n=94 which have been used in the aquaculture industry for several decades. Antibiotic resistant patterns should be continuously monitored to predict the emergence and widespread of MAR. Effective action is needed to keep the new resistance from further developing and spreading.

  16. Antibiotic-resistant bacteria: a challenge for the food industry.

    Science.gov (United States)

    Capita, Rosa; Alonso-Calleja, Carlos

    2013-01-01

    Antibiotic-resistant bacteria were first described in the 1940s, but whereas new antibiotics were being discovered at a steady rate, the consequences of this phenomenon were slow to be appreciated. At present, the paucity of new antimicrobials coming into the market has led to the problem of antibiotic resistance fast escalating into a global health crisis. Although the selective pressure exerted by the use of antibiotics (particularly overuse or misuse) has been deemed the major factor in the emergence of bacterial resistance to these antimicrobials, concerns about the role of the food industry have been growing in recent years and have been raised at both national and international levels. The selective pressure exerted by the use of antibiotics (primary production) and biocides (e.g., disinfectants, food and feed preservatives, or decontaminants) is the main driving force behind the selection and spread of antimicrobial resistance throughout the food chain. Genetically modified (GM) crops with antibiotic resistance marker genes, microorganisms added intentionally to the food chain (probiotic or technological) with potentially transferable antimicrobial resistance genes, and food processing technologies used at sub-lethal doses (e.g., alternative non-thermal treatments) are also issues for concern. This paper presents the main trends in antibiotic resistance and antibiotic development in recent decades, as well as their economic and health consequences, current knowledge concerning the generation, dissemination, and mechanisms of antibacterial resistance, progress to date on the possible routes for emergence of resistance throughout the food chain and the role of foods as a vehicle for antibiotic-resistant bacteria. The main approaches to prevention and control of the development, selection, and spread of antibacterial resistance in the food industry are also addressed.

  17. [State-of-the-art status on airborne antibiotic resistant bacteria and antibiotic resistance genes].

    Science.gov (United States)

    Li, J; Yao, M S

    2018-04-06

    The world is facing more deaths due to increasing antibiotic-resistant bacterial infections and the shortage of new highly effective antibiotics, however the air media as its important transmission route has not been adequately studied. Based on the latest literature acquired in this work, we have discussed the state-of-the-art research progress of the concentration, distribution and spread of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in different environmental air media, and also analyzed some future prevention and control measures. The large use of antibiotics in the medical settings and animal husbandry places has resulted in higher abundances of ARB and ARGs in the relevant and surrounding atmosphere than in urban and general indoor air environments. ARGs can be spread by adhering to airborne particles, and researchers have also found that air media contain more abundant ARGs than other environmental media such as soil, water and sediment. It was suggested in this review that strengthening the monitoring, study on spreading factors and biological toxicity, and also research and development on pathogen accurate diagnosis and new green antibiotic are expected to help effectively monitor, prevent and control of the impacts of airborne resistant bacteria and resistance genes on both human and ecologies.

  18. Antibiotic Resistance of Bacteria: A Global Challenge

    Indian Academy of Sciences (India)

    protein that functions as an elctroneutral antiport system. The .... isolates, obtained from north Bengal, and over the counter sale of the same antibiotics in and around .... biology is being applied to rapidly explore and optimize the interactions ...

  19. The expression of antibiotic resistance genes in antibiotic-producing bacteria.

    Science.gov (United States)

    Mak, Stefanie; Xu, Ye; Nodwell, Justin R

    2014-08-01

    Antibiotic-producing bacteria encode antibiotic resistance genes that protect them from the biologically active molecules that they produce. The expression of these genes needs to occur in a timely manner: either in advance of or concomitantly with biosynthesis. It appears that there have been at least two general solutions to this problem. In many cases, the expression of resistance genes is tightly linked to that of antibiotic biosynthetic genes. In others, the resistance genes can be induced by their cognate antibiotics or by intermediate molecules from their biosynthetic pathways. The regulatory mechanisms that couple resistance to antibiotic biosynthesis are mechanistically diverse and potentially relevant to the origins of clinical antibiotic resistance. © 2014 John Wiley & Sons Ltd.

  20. Antibiotic-Resistant Enteric Bacteria in Environmental Waters

    Directory of Open Access Journals (Sweden)

    Lisa M. Casanova

    2016-11-01

    Full Text Available Sources of antibiotic resistant organisms, including concentrated animal feeding operations (CAFOs, may lead to environmental surface and groundwater contamination with resistant enteric bacteria of public health concern. The objective of this research is to determine whether Salmonella, Escherichia coli, Yersinia enterocolitica, and enterococci resistant to clinically relevant antibiotics are present in surface and groundwater sources in two eastern North Carolina counties, Craven and Wayne. 100 surface and groundwater sites were sampled for Salmonella, E. coli, and enterococci, and the bacteria isolated from these samples were tested for susceptibility to clinically relevant antibiotics. Salmonella were detected at low levels in some surface but not groundwater. E. coli were in surface waters but not ground in both counties. Enterococci were present in surface water and a small number of groundwater sites. Yersinia was not found. Bacterial densities were similar in both counties. For Salmonella in surface water, the most frequent type of resistance was to sulfamethoxazole. There was no ciprofloxacin resistance. There were a few surface water E. coli isolates resistant to chloramphenicol, gentamicin, and ampicillin. Enterococci in surface water had very low levels of resistance to vancomycin, chloramphenicol, ampicillin, and streptomycin. E. coli and enterococci are present more frequently and at higher levels in surface water than Salmonella, but groundwater contamination with any of these organisms was rare, and low levels of resistance can be found sporadically. Resistant bacteria are relatively uncommon in these eastern N.C. surface and groundwaters, but they could pose a risk of human exposure via ingestion or primary contact recreation.

  1. Temperate and lytic bacteriophages programmed to sensitize and kill antibiotic-resistant bacteria.

    Science.gov (United States)

    Yosef, Ido; Manor, Miriam; Kiro, Ruth; Qimron, Udi

    2015-06-09

    The increasing threat of pathogen resistance to antibiotics requires the development of novel antimicrobial strategies. Here we present a proof of concept for a genetic strategy that aims to sensitize bacteria to antibiotics and selectively kill antibiotic-resistant bacteria. We use temperate phages to deliver a functional clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated (Cas) system into the genome of antibiotic-resistant bacteria. The delivered CRISPR-Cas system destroys both antibiotic resistance-conferring plasmids and genetically modified lytic phages. This linkage between antibiotic sensitization and protection from lytic phages is a key feature of the strategy. It allows programming of lytic phages to kill only antibiotic-resistant bacteria while protecting antibiotic-sensitized bacteria. Phages designed according to this strategy may be used on hospital surfaces and hand sanitizers to facilitate replacement of antibiotic-resistant pathogens with sensitive ones.

  2. Combating Antibiotic Resistance

    Science.gov (United States)

    ... Bacteria Phasing Out Certain Antibiotic Use in Farm Animals FDA: Cutting-Edge Technology Sheds Light on Antibiotic Resistance For More Information Antibiotics and Antibiotic Resistance Antimicrobial Resistance Information for Consumers and Health Professionals CDC: ...

  3. Vanillin selectively modulates the action of antibiotics against resistant bacteria.

    Science.gov (United States)

    Bezerra, Camila Fonseca; Camilo, Cicera Janaine; do Nascimento Silva, Maria Karollyna; de Freitas, Thiago Sampaio; Ribeiro-Filho, Jaime; Coutinho, Henrique Douglas Melo

    2017-12-01

    The treatment of infections caused by microorganisms that are resistant to antibiotics represent one of the main challenges of medicine today, especially due to the inefficacy of long-term drug therapy. In the search for new alternatives to treat these infections, many researchers have been looking for new substances derived from natural products to replace, or be used in combination with conventional antibiotics. Vanillin is a phenolic compound whose antimicrobial activity has been used in the elimination of pathogens present in fruits and vegetables. However, its antibacterial and modulating properties remain to be characterized. Therefore, this work aimed to evaluate the antibacterial activity and analyze the modulator activity of vanillin in association with conventional antibiotics. The antimicrobial activity of vanillin was evaluated using the microdilution method to determine the Minimum Inhibitory Concentration (MIC) Standard strains of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and multi-resistant strains of Escherichia coli 06, Staphylococcus aureus 10, Pseudomonas aeruginosa 24 were used in this study. The antibiotic modulating effect was analyzed by combining vanillin with Norfloxacin, Imipenem, Gentamicin, Erythromycin and Tetracycline against the following multiresistant bacteria strains: Escherichia coli 06, Staphylococcus aureus 10 and Pseudomonas aeruginosa 24. Data were analyzed using the ANOVA test of two tracks followed by the post hoc Bonferroni test. Vanillin presented CIMs ≥1024μg/mL against all tested strains demonstrating that it did not present significant antibacterial activity. However, modulated the activity of gentamicin and imipenem against S. aureus and E. coli, causing a synergistic effect, but did not affect the activity of norfloxacin, tetracycline and erythromycin against these same microorganisms. A synergistic effect was also obtained from the association of vanillin with norfloxacin against P

  4. Antibiotic resistance shaping multilevel population biology of bacteria

    Directory of Open Access Journals (Sweden)

    Fernando eBaquero

    2013-03-01

    Full Text Available Antibiotics have natural functions, mostly involving cell-to-cell signalling networks. The anthropogenic production of antibiotics, and its release in the microbiosphere results in a disturbance of these networks, antibiotic resistance tending to preserve its integrity. The cost of such adaptation is the emergence and dissemination of antibiotic resistance genes, and of all genetic and cellular vehicles in which these genes are located. Selection of the combinations of the different evolutionary units (genes, integrons, transposons, plasmids, cells, communities and microbiomes, hosts is highly asymmetrical. Each unit of selection is a self-interested entity, exploiting the higher hierarchical unit for its own benefit, but in doing so the higher hierarchical unit might acquire critical traits for its spread because of the exploitation of the lower hierarchical unit. This interactive trade-off shapes the population biology of antibiotic resistance, a composed-complex array of the independent population biologies. Antibiotics modify the abundance and the interactive field of each of these units. Antibiotics increase the number and evolvability of clinical antibiotic resistance genes, but probably also many other genes with different primary functions but with a resistance phenotype present in the environmental resistome. Antibiotics influence the abundance, modularity, and spread of integrons, transposons and plasmids, mostly acting on structures present before the antibiotic era. Antibiotics enrich particular bacterial lineages and clones and contribute to local clonalization processes. Antibiotics amplify particular genetic exchange communities sharing antibiotic resistance genes and platforms within microbiomes. In particular human or animal hosts, the microbiomic composition might facilitate the interactions between evolutionary units involved in antibiotic resistance. The understanding of antibiotic resistance implies expanding our knowledge

  5. Antibiotics and Antibiotic Resistance

    Science.gov (United States)

    ... all that ails you. Antibiotics, also known as antimicrobial drugs, are drugs that fight infections caused by bacteria. ... Information for Consumers and Health Professionals Information by drug class Antimicrobial Resistance Animal and Veterinary Related Resources Further information ...

  6. Occurrence of antibiotic resistant bacteria in dogs presented with ...

    African Journals Online (AJOL)

    Otitis is one of the most common infections in dogs. This has been associated with misuse of antibiotics thereby promoting the emergence of multi-resistant micro-organisms. This study was conducted to determine the occurrence and the antibiotic resistance pattern of bacterial pathogens associated with otitis in dogs ...

  7. Resistance to antibiotics in Lacid acid bacteria - strain Lactococcus

    Directory of Open Access Journals (Sweden)

    Filipić Brankica

    2015-01-01

    Full Text Available Lactic acid bacteria (LAB are widely used in the food industry, especially in the production of fermented dairy products and meat. The most studied species among Lis Lactococcus lactis. L. lactis strains are of great importance in the production of fermented dairy products such as yogurt, butter, fresh cheese and some kind of semi-hard cheese. Although L. lactis acquired the „Generally Regarded As Safe“ (GRAS status, many investigations indicated that lactococci may act as reservoirs of antibiotic resistance genes, which could be transferred to other bacterial species in human gastrointestinal tract includ­ing pathogens. The genome analysis of L. lactis indicated the presence of at least 40 putative drug transporter genes, and only four multidrug resistance (MDR transporters are functionally characterized: LmrA, LmrP, LmrCD i CmbT. LmrA is the first described MDR transporter in prokaryotes. LmrCD is responsible for resistance to cholate, which is an integral part of human bile and LmrCD is important for intestinal survival of lactococci that are used as probiotics. Secondary multidrug transporter LmrP confers resistance to lincosamides, macrolides, streptogramins and tetracyclines. CmbT protein has an effect on the host cell resistance to lincomycin, sulfadiazine, streptomycin, rifampicin, puromycin and sulfametox­azole. Since the food chain is an important way of transmitting resistance genes in human and animal population, it is of great importance to study the mechanisms of resistance in lactococci and other LAB, intended for the food industry. [Projekat Ministarstva nauke Republike Srbije, br. 173019: Izučavanje gena i molekularnih mehanizama u osnovi probiotičke aktivnosti bakterija mlečne kiseline izolovanih sa područja Zapadnog Balkana

  8. Antibiotic resistance

    Directory of Open Access Journals (Sweden)

    Marianne Frieri

    2017-07-01

    Full Text Available Summary: Antimicrobial resistance in bacterial pathogens is a challenge that is associated with high morbidity and mortality. Multidrug resistance patterns in Gram-positive and -negative bacteria are difficult to treat and may even be untreatable with conventional antibiotics. There is currently a shortage of effective therapies, lack of successful prevention measures, and only a few new antibiotics, which require development of novel treatment options and alternative antimicrobial therapies. Biofilms are involved in multidrug resistance and can present challenges for infection control. Virulence, Staphylococcus aureus, Clostridium difficile infection, vancomycin-resistant enterococci, and control in the Emergency Department are also discussed. Keywords: Antibiotic resistance, Biofilms, Infections, Public health, Emergency Department

  9. [From the discovery of antibiotics to emerging highly drug-resistant bacteria].

    Science.gov (United States)

    Meunier, Olivier

    2015-01-01

    The discovery of antibiotics has enabled serious infections to be treated. However, bacteria resistant to several families of antibiotics and the emergence of new highly drug-resistant bacteria constitute a public health issue in France and across the world. Actions to prevent their transmission are being put in place. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  10. Irrigation waters and pipe-based biofilms as sources for antibiotic-resistant bacteria

    Science.gov (United States)

    The presence of antibiotic-resistant bacteria in environmental surface waters has gained recent attention. Wastewater- and drinking water distribution systems are known to disseminate antibiotic-resistant bacteria, with the biofilms that form on the inner-surfaces of the pipeline as a hotspot for pr...

  11. Emerging antibiotic resistance in bacteria with special reference to ...

    Indian Academy of Sciences (India)

    Prakash

    utility of antibiotics in the control of infections has been indicated. [Raghunath D 2008 ..... 6.4 Protozoa. Plasmodium falciparum has become resistant to chloroquin ... The partial success of a polysaccharide vaccine against S. aureus in ...

  12. Diversity and antibiotic resistance of uropathogenic bacteria from ...

    African Journals Online (AJOL)

    J.-L.A. Moroh

    Background: Urinary tract infections (UTI) are one of the major causes of ... were processed to obtain the profile prevalence of UTI, the rate of bacterial resistance to antibiotics, the ..... tance patterns of outpatient pediatric urinary tract infections.

  13. Resistance of Bacteria Isolated from Otamiri River to Heavy Metals and Some Selected Antibiotics

    OpenAIRE

    I.C. Mgbemena; J.C. Nnokwe; L.A. Adjeroh; N.N. Onyemekara

    2012-01-01

    This study is aimed at determining the resistance of bacteria to heavy metals and some antibiotics. The ability of aquatic bacteria isolates from Otamiri River at Ihiagwa in Owerri North, Imo State to tolerate or resist the presence of certain selected heavy metals: Pb+, Zn2+ and Fe2+ and some antibiotics was investigated. Identification tests for the bacteria isolates from Otamiri River revealed them to belong to the genera Pseudomonas, Aeromonas, Bacillus, Escherichia, Micrococcus and Prote...

  14. Antibiotic prophylaxis in the era of multidrug-resistant bacteria.

    Science.gov (United States)

    Wittekamp, Bastiaan H J; Bonten, Marc J M

    2012-06-01

    The prophylactic use of antibiotics can only be justified when clinical benefits on relevant patient outcomes, such as morbidity or mortality, cost-effectiveness, and absence of immediate emergence of antibiotic resistance have been unequivocally demonstrated. In some intensive care unit (ICU) patients, antibiotic prophylaxis is used as part of selective digestive tract decontamination (SDD) and selective oropharyngeal decontamination (SOD). Recent trials in ICUs with low levels of antibiotic resistance strongly suggest that both regimens reduce the incidence of ICU-acquired infections and improve patient survival. Naturally, the unique microbial ecology of such settings reduce generalizability of results. Therefore, the routine use of SOD and SDD remains highly controversial, especially in ICUs with higher levels of antibiotic resistance. Moreover, convincing evidence is still missing on several important aspects related to efficacy and safety. Despite numerous trials, effects of SDD and SOD on antibiotic resistance during and after decolonization treatment have still been insufficiently investigated, and existing results are contradicting. Furthermore, the effects of both regimens on the non-culturable part of the intestinal flora remain unknown. Finally, cost-effectiveness has not been thoroughly investigated, and prices of the antimicrobial agents that have been used have increased dramatically in recent years. In this review, important knowledge gaps that so far prevent the widespread use of SDD and SOD will be addressed.

  15. Release of Antibiotic Resistant Bacteria by a Waste Treatment Plant from Romania.

    Science.gov (United States)

    Lupan, Iulia; Carpa, Rahela; Oltean, Andreea; Kelemen, Beatrice Simona; Popescu, Octavian

    2017-09-27

    The occurrence and spread of bacterial antibiotic resistance are subjects of great interest, and the role of wastewater treatment plants has been attracting particular interest. These stations are a reservoir of bacteria, have a large range of organic and inorganic substances, and the amount of bacteria released into the environment is very high. The main purpose of the present study was to assess the removal degree of bacteria with resistance to antibiotics and identify the contribution of a wastewater treatment plant to the microbiota of Someşul Mic river water in Cluj county. The resistance to sulfamethoxazole and tetracycline and some of their representative resistance genes: sul1, tet(O), and tet(W) were assessed in this study. The results obtained showed that bacteria resistant to sulphonamides were more abundant than those resistant to tetracycline. The concentration of bacteria with antibiotic resistance changed after the treatment, namely, bacteria resistant to sulfamethoxazole. The removal of all bacteria and antibiotic-resistant bacteria was 98-99% and the degree of removal of bacteria resistant to tetracycline was higher than the bacteria resistant to sulfamethoxazole compared to total bacteria. The wastewater treatment plant not only contributed to elevating ARG concentrations, it also enhanced the possibility of horizontal gene transfer (HGT) by increasing the abundance of the intI1 gene. Even though the treatment process reduced the concentration of bacteria by two orders of magnitude, the wastewater treatment plant in Cluj-Napoca contributed to an increase in antibiotic-resistant bacteria concentrations up to 10 km downstream of its discharge in Someşul Mic river.

  16. Association of metal tolerance with multiple antibiotic resistance of bacteria isolated from drinking water.

    Science.gov (United States)

    Calomiris, J J; Armstrong, J L; Seidler, R J

    1984-06-01

    Bacterial isolates from the drinking water system of an Oregon coastal community were examined to assess the association of metal tolerance with multiple antibiotic resistance. Positive correlations between tolerance to high levels of Cu2+, Pb2+, and Zn2+ and multiple antibiotic resistance were noted among bacteria from distribution waters but not among bacteria from raw waters. Tolerances to higher levels of Al3+ and Sn2+ were demonstrated more often by raw water isolates which were not typically multiple antibiotic resistant. A similar incidence of tolerance to Cd2+ was demonstrated by isolates of both water types and was not associated with multiple antibiotic resistance. These results suggest that simultaneous selection phenomena occurred in distribution water for bacteria which exhibited unique patterns of tolerance to Cu2+, Pb2+, and Zn2+ and antibiotic resistance.

  17. The culturable soil antibiotic resistome: a community of multi-drug resistant bacteria.

    Science.gov (United States)

    Walsh, Fiona; Duffy, Brion

    2013-01-01

    Understanding the soil bacterial resistome is essential to understanding the evolution and development of antibiotic resistance, and its spread between species and biomes. We have identified and characterized multi-drug resistance (MDR) mechanisms in the culturable soil antibiotic resistome and linked the resistance profiles to bacterial species. We isolated 412 antibiotic resistant bacteria from agricultural, urban and pristine soils. All isolates were multi-drug resistant, of which greater than 80% were resistant to 16-23 antibiotics, comprising almost all classes of antibiotic. The mobile resistance genes investigated, (ESBL, bla NDM-1, and plasmid mediated quinolone resistance (PMQR) resistance genes) were not responsible for the respective resistance phenotypes nor were they present in the extracted soil DNA. Efflux was demonstrated to play an important role in MDR and many resistance phenotypes. Clinically relevant Burkholderia species are intrinsically resistant to ciprofloxacin but the soil Burkholderia species were not intrinsically resistant to ciprofloxacin. Using a phenotypic enzyme assay we identified the antibiotic specific inactivation of trimethoprim in 21 bacteria from different soils. The results of this study identified the importance of the efflux mechanism in the soil resistome and variations between the intrinsic resistance profiles of clinical and soil bacteria of the same family.

  18. The culturable soil antibiotic resistome: a community of multi-drug resistant bacteria.

    Directory of Open Access Journals (Sweden)

    Fiona Walsh

    Full Text Available Understanding the soil bacterial resistome is essential to understanding the evolution and development of antibiotic resistance, and its spread between species and biomes. We have identified and characterized multi-drug resistance (MDR mechanisms in the culturable soil antibiotic resistome and linked the resistance profiles to bacterial species. We isolated 412 antibiotic resistant bacteria from agricultural, urban and pristine soils. All isolates were multi-drug resistant, of which greater than 80% were resistant to 16-23 antibiotics, comprising almost all classes of antibiotic. The mobile resistance genes investigated, (ESBL, bla NDM-1, and plasmid mediated quinolone resistance (PMQR resistance genes were not responsible for the respective resistance phenotypes nor were they present in the extracted soil DNA. Efflux was demonstrated to play an important role in MDR and many resistance phenotypes. Clinically relevant Burkholderia species are intrinsically resistant to ciprofloxacin but the soil Burkholderia species were not intrinsically resistant to ciprofloxacin. Using a phenotypic enzyme assay we identified the antibiotic specific inactivation of trimethoprim in 21 bacteria from different soils. The results of this study identified the importance of the efflux mechanism in the soil resistome and variations between the intrinsic resistance profiles of clinical and soil bacteria of the same family.

  19. Metal and antibiotic-resistance in psychrotrophic bacteria from Antarctic marine waters

    Digital Repository Service at National Institute of Oceanography (India)

    De; Nair, S.; LokaBharathi, P.A.; Chandramohan, D.

    In the wake of the findings that Antarctic krills concentrate heavy metals at ppm level, (Yamamoto et al., 1987), the Antarctic waters from the Indian side were examined for the incidence of metal and antibiotic-resistant bacteria during...

  20. Surveillance of Antibiotic-Resistant Bacteria from Wastewater Effluents Across the United States

    Science.gov (United States)

    This presentation will inform the audience of the purpose and importance of the antibiotic resistant bacteria surveillances that have been conducted to date. And an overview of why the EPA is looking into this problem in wastewater effluents.

  1. Discovery, research, and development of new antibiotics: the WHO priority list of antibiotic-resistant bacteria and tuberculosis.

    Science.gov (United States)

    Tacconelli, Evelina; Carrara, Elena; Savoldi, Alessia; Harbarth, Stephan; Mendelson, Marc; Monnet, Dominique L; Pulcini, Céline; Kahlmeter, Gunnar; Kluytmans, Jan; Carmeli, Yehuda; Ouellette, Marc; Outterson, Kevin; Patel, Jean; Cavaleri, Marco; Cox, Edward M; Houchens, Chris R; Grayson, M Lindsay; Hansen, Paul; Singh, Nalini; Theuretzbacher, Ursula; Magrini, Nicola

    2018-03-01

    The spread of antibiotic-resistant bacteria poses a substantial threat to morbidity and mortality worldwide. Due to its large public health and societal implications, multidrug-resistant tuberculosis has been long regarded by WHO as a global priority for investment in new drugs. In 2016, WHO was requested by member states to create a priority list of other antibiotic-resistant bacteria to support research and development of effective drugs. We used a multicriteria decision analysis method to prioritise antibiotic-resistant bacteria; this method involved the identification of relevant criteria to assess priority against which each antibiotic-resistant bacterium was rated. The final priority ranking of the antibiotic-resistant bacteria was established after a preference-based survey was used to obtain expert weighting of criteria. We selected 20 bacterial species with 25 patterns of acquired resistance and ten criteria to assess priority: mortality, health-care burden, community burden, prevalence of resistance, 10-year trend of resistance, transmissibility, preventability in the community setting, preventability in the health-care setting, treatability, and pipeline. We stratified the priority list into three tiers (critical, high, and medium priority), using the 33rd percentile of the bacterium's total scores as the cutoff. Critical-priority bacteria included carbapenem-resistant Acinetobacter baumannii and Pseudomonas aeruginosa, and carbapenem-resistant and third-generation cephalosporin-resistant Enterobacteriaceae. The highest ranked Gram-positive bacteria (high priority) were vancomycin-resistant Enterococcus faecium and meticillin-resistant Staphylococcus aureus. Of the bacteria typically responsible for community-acquired infections, clarithromycin-resistant Helicobacter pylori, and fluoroquinolone-resistant Campylobacter spp, Neisseria gonorrhoeae, and Salmonella typhi were included in the high-priority tier. Future development strategies should focus on

  2. The Structure of Fitness Landscapes in Antibiotic-Resistant Bacteria

    Science.gov (United States)

    Deris, Barrett; Kim, Minsu; Zhang, Zhongge; Okano, Hiroyuki; Hermsen, Rutger; Gore, Jeff; Hwa, Terence

    2014-03-01

    To predict the emergence of antibiotic resistance, quantitative relations must be established between the fitness of drug-resistant organisms and the molecular mechanisms conferring resistance. We have investigated E. coli strains expressing resistance to translation-inhibiting antibiotics. We show that resistance expression and drug inhibition are linked in a positive feedback loop arising from an innate, global effect of drug-inhibited growth on gene expression. This feedback leads generically to plateau-shaped fitness landscapes and concomitantly, for strains expressing at least moderate degrees of drug resistance, gives rise to an abrupt drop in growth rates of cultures at threshold drug concentrations. A simple quantitative model of bacterial growth based on this innate feedback accurately predicts experimental observations without ad hoc parameter fitting. We describe how drug-inhibited growth rate and the threshold drug concentration (the minimum inhibitory concentration, or MIC) depend on the few biochemical parameters that characterize the molecular details of growth inhibition and drug resistance (e.g., the drug-target dissociation constant). And finally, we discuss how these parameters can shape fitness landscapes to determine evolutionary dynamics and evolvability.

  3. HEAVY METAL AND ANTIBIOTIC RESISTANCE BACTERIA IN MARINE SEDIMENT OF PAHANG COASTAL WATER

    Directory of Open Access Journals (Sweden)

    Zaima Azira

    2018-01-01

    Full Text Available The presence of heavy metal and antibiotic resistance bacteria in the marine sediment may indicate heavy metal pollution and antibiotic abuse present in the environment. In this study, a total of 89 bacteria isolated from sediment collected in Teluk Chempedak and Pantai Batu Hitam of Pahang coastal water underwent heavy metal resistance test against Chromium, Cadmium, Nickel, Copper and Cobalt. Previously, these isolates were found to exhibit antibiotic resistance capabilities to at least 5 antibiotics tested. Heavy metal resistance pattern for isolates from Teluk Chempedak was in the form of Cr > Ni >Co >Cd = Cu while for isolates from Pantai Batu Hitam showed a pattern of Cr = Ni >Co >Cu >Cd. Further investigation on the identity of selected isolates that exhibited both antibiotic and heavy metals resistance capabilities using 16S rRNA gene sequences revealed isolates with closest similarities to Staphylococcus saprophyticus and Brevundimonas vesicularis..

  4. Antibiotic Resistance

    DEFF Research Database (Denmark)

    Munck, Christian

    morbidity and mortality as well as an increase in the cost of treatment. Understanding how bacteria respond to antibiotic exposure gives the foundations for a rational approach to counteract antimicrobial resistance. In the work presented in this thesis, I explore the two fundamental sources...... of antimicrobial resistance: (1) adaptive mutations and (2) horizontal acquisition of resistance genes from antibiotic gene reservoirs. By studying the geno- and phenotypic changes of E. coli in response to single and drug-pair exposures, I uncover the evolutionary trajectories leading to adaptive resistance. I...... to rationally design drug combinations that limit the evolution of antibiotic resistance due to counteracting evolutionary trajectories. My results highlight that an in-depth knowledge about the genetic responses to the individual antimicrobial compounds enables the prediction of responses to drug combinations...

  5. Do antibiotic residues in soils play a role in amplification and transmission of antibiotic resistant bacteria in cattle populations?

    Directory of Open Access Journals (Sweden)

    Douglas Ruben Call

    2013-07-01

    Full Text Available When we consider factors that contribute to the emergence, amplification, and persistence of antibiotic resistant bacteria, the conventional assumption is that antibiotic use is the primary driver in these processes and that selection occurs primarily in the patient or animal. Evidence suggests that this may not always be the case. Experimental trials show that parenteral administration of a third-generation cephalosporin (ceftiofur in cattle has limited or short-term effects on the prevalence of ceftiofur-resistant bacteria in the gastrointestinal tract. While this response may be sufficient to explain a pattern of widespread resistance to cephalosporins, approximately two-thirds of ceftiofur metabolites are excreted in the urine raising the possibility that environmental selection plays an important additive role in the amplification and maintenance of antibiotic resistant E. coli on farms. Consequently, we present a rationale for an environmental selection hypothesis whereby excreted antibiotic residues such as ceftiofur are a significant contributor to the proliferation of antibiotic resistant bacteria in food animal systems. We also present a mathematical model of our hypothesized system as a guide for designing experiments to test this hypothesis. If supported for antibiotics such as ceftiofur, then there may be new approaches to combat the proliferation of antibiotic resistance beyond the prudent use mantra.

  6. Functional Characterization of Bacteria Isolated from Ancient Arctic Soil Exposes Diverse Resistance Mechanisms to Modern Antibiotics

    Science.gov (United States)

    Perron, Gabriel G.; Whyte, Lyle; Turnbaugh, Peter J.; Goordial, Jacqueline; Hanage, William P.; Dantas, Gautam; Desai, Michael M.

    2015-01-01

    Using functional metagenomics to study the resistomes of bacterial communities isolated from different layers of the Canadian high Arctic permafrost, we show that microbial communities harbored diverse resistance mechanisms at least 5,000 years ago. Among bacteria sampled from the ancient layers of a permafrost core, we isolated eight genes conferring clinical levels of resistance against aminoglycoside, β-lactam and tetracycline antibiotics that are naturally produced by microorganisms. Among these resistance genes, four also conferred resistance against amikacin, a modern semi-synthetic antibiotic that does not naturally occur in microorganisms. In bacteria sampled from the overlaying active layer, we isolated ten different genes conferring resistance to all six antibiotics tested in this study, including aminoglycoside, β-lactam and tetracycline variants that are naturally produced by microorganisms as well as semi-synthetic variants produced in the laboratory. On average, we found that resistance genes found in permafrost bacteria conferred lower levels of resistance against clinically relevant antibiotics than resistance genes sampled from the active layer. Our results demonstrate that antibiotic resistance genes were functionally diverse prior to the anthropogenic use of antibiotics, contributing to the evolution of natural reservoirs of resistance genes. PMID:25807523

  7. Antibiotic resistance in bacteria associated with food animals: a United States perspective of livestock production.

    Science.gov (United States)

    Mathew, Alan G; Cissell, Robin; Liamthong, S

    2007-01-01

    The use of antimicrobial compounds in food animal production provides demonstrated benefits, including improved animal health, higher production and, in some cases, reduction in foodborne pathogens. However, use of antibiotics for agricultural purposes, particularly for growth enhancement, has come under much scrutiny, as it has been shown to contribute to the increased prevalence of antibiotic-resistant bacteria of human significance. The transfer of antibiotic resistance genes and selection for resistant bacteria can occur through a variety of mechanisms, which may not always be linked to specific antibiotic use. Prevalence data may provide some perspective on occurrence and changes in resistance over time; however, the reasons are diverse and complex. Much consideration has been given this issue on both domestic and international fronts, and various countries have enacted or are considering tighter restrictions or bans on some types of antibiotic use in food animal production. In some cases, banning the use of growth-promoting antibiotics appears to have resulted in decreases in prevalence of some drug resistant bacteria; however, subsequent increases in animal morbidity and mortality, particularly in young animals, have sometimes resulted in higher use of therapeutic antibiotics, which often come from drug families of greater relevance to human medicine. While it is clear that use of antibiotics can over time result in significant pools of resistance genes among bacteria, including human pathogens, the risk posed to humans by resistant organisms from farms and livestock has not been clearly defined. As livestock producers, animal health experts, the medical community, and government agencies consider effective strategies for control, it is critical that science-based information provide the basis for such considerations, and that the risks, benefits, and feasibility of such strategies are fully considered, so that human and animal health can be maintained while

  8. Antibiotic resistance in triclosan heterotrophic plate count bacteria from sewage water / Ilsé Coetzee

    OpenAIRE

    Coetzee, Ilsé

    2015-01-01

    The concentration of triclosan in antiseptics, disinfectants and preservatives in products exceeds the minimal lethal levels. Extensive use of triclosan and antibiotics results in bacterial resistance to their active ingredients. The precise relationship between use and resistance, however, has been challenging to define. The aim of the study was to identify and determine antibiotic resistance profiles of triclosan tolerant heterotrophic plate count bacteria isolates from sewag...

  9. Influence of Chicken Manure Fertilization on Antibiotic-Resistant Bacteria in Soil and the Endophytic Bacteria of Pakchoi

    Directory of Open Access Journals (Sweden)

    Qingxiang Yang

    2016-06-01

    Full Text Available Animal manure is commonly used as fertilizer for agricultural crops worldwide, even though it is believed to contribute to the spread of antibiotic resistance from animal intestines to the soil environment. However, it is unclear whether and how there is any impact of manure fertilization on populations and community structure of antibiotic-resistant endophytic bacteria (AREB in plant tissues. To investigate the effect of manure and organic fertilizer on endophytic bacterial communities, pot experiments were performed with pakchoi grown with the following treatments: (1 non-treated; (2 chicken manure-treated and (3 organic fertilizer-treated. Manure or organic fertilizer significantly increased the abundances of total cultivable endophytic bacteria (TCEB and AREB in pakchoi, and the effect of chicken manure was greater than that of organic fertilizer. Further, 16S rDNA sequencing and the phylogenetic analysis indicated that chicken manure or organic fertilizer application increased the populations of multiple antibiotic-resistant bacteria (MARB in soil and multiple antibiotic-resistant endophytic bacteria (MAREB in pakchoi. The identical multiple antibiotic-resistant bacterial populations detected in chicken manure, manure- or organic fertilizer-amended soil and the vegetable endophytic system were Brevundimonas diminuta, Brachybacterium sp. and Bordetella sp., suggesting that MARB from manure could enter and colonize the vegetable tissues through manure fertilization. The fact that some human pathogens with multiple antibiotic resistance were detected in harvested vegetables after growing in manure-amended soil demonstrated a potential threat to human health.

  10. Antibiotic-resistant genes and antibiotic-resistant bacteria in the effluent of urban residential areas, hospitals, and a municipal wastewater treatment plant system.

    Science.gov (United States)

    Li, Jianan; Cheng, Weixiao; Xu, Like; Strong, P J; Chen, Hong

    2015-03-01

    In this study, we determined the abundance of 8 antibiotics (3 tetracyclines, 4 sulfonamides, and 1 trimethoprim), 12 antibiotic-resistant genes (10 tet, 2 sul), 4 antibiotic-resistant bacteria (tetracycline, sulfamethoxazole, and combined resistance), and class 1 integron integrase gene (intI1) in the effluent of residential areas, hospitals, and municipal wastewater treatment plant (WWTP) systems. The concentrations of total/individual targets (antibiotics, genes, and bacteria) varied remarkably among different samples, but the hospital samples generally had a lower abundance than the residential area samples. The WWTP demonstrated removal efficiencies of 50.8% tetracyclines, 66.8% sulfonamides, 0.5 logs to 2.5 logs tet genes, and less than 1 log of sul and intI1 genes, as well as 0.5 log to 1 log removal for target bacteria. Except for the total tetracycline concentration and the proportion of tetracycline-resistant bacteria (R (2) = 0.330, P antibiotics and the corresponding resistant bacteria (P > 0.05). In contrast, various relationships were identified between antibiotics and antibiotic resistance genes (P antibiotic-resistant bacteria (P < 0.01).

  11. Antibiotic-resistant fecal bacteria, antibiotics, and mercury in surface waters of Oakland County, Michigan, 2005-2006

    Science.gov (United States)

    Fogarty, Lisa R.; Duris, Joseph W.; Crowley, Suzanne L.; Hardigan, Nicole

    2007-01-01

    Water samples collected from 20 stream sites in Oakland and Macomb Counties, Mich., were analyzed to learn more about the occurrence of cephalosporin-resistant Escherichia coli (E. coli) and vancomycin-resistant enterococci (VRE) and the co-occurrence of antibiotics and mercury in area streams. Fecal indicator bacteria concentrations exceeded the Michigan recreational water-quality standard of 300 E. coli colony forming units (CFU) per 100 milliliters of water in 19 of 35 stream-water samples collected in Oakland County. A gene commonly associated with enterococci from humans was detected in samples from Paint Creek at Rochester and Evans Ditch at Southfield, indicating that human fecal waste is a possible source of fecal contamination at these sites. E. coli resistant to the cephalosporin antibiotics (cefoxitin and/ or ceftriaxone) were found at all sites on at least one occasion. The highest percentages of E. coli isolates resistant to cefoxitin and ceftriaxone were 71 percent (Clinton River at Auburn Hills) and 19 percent (Sashabaw Creek near Drayton Plains), respectively. Cephalosporin-resistant E. coli was detected more frequently in samples from intensively urbanized or industrialized areas than in samples from less urbanized areas. VRE were not detected in any sample collected in this study. Multiple antibiotics (azithromycin, erythromycin, ofloxacin, sulfamethoxazole, and trimethoprim) were detected in water samples from the Clinton River at Auburn Hills, and tylosin (an antibiotic used in veterinary medicine and livestock production that belongs to the macrolide group, along with erythromycin) was detected in one water sample from Paint Creek at Rochester. Concentrations of total mercury were as high as 19.8 nanograms per liter (Evans Ditch at Southfield). There was no relation among percentage of antibiotic-resistant bacteria and measured concentrations of antibiotics or mercury in the water. Genetic elements capable of exchanging multiple antibiotic-resistance

  12. Emergence of antibiotic-resistant bacteria in patients with Fournier gangrene.

    Science.gov (United States)

    Lin, Wei-Ting; Chao, Chien-Ming; Lin, Hsin-Lan; Hung, Ming-Chran; Lai, Chih-Cheng

    2015-04-01

    This study was conducted to investigate the bacteriology and associated patterns of antibiotic resistance Fournier gangrene. Patients with Fournier's gangrene from 2008 to 2012 were identified from the computerized database in a medical center in southern Taiwan. The medical records of all patients with Fournier's gangrene were reviewed retrospectively. There were 61 microorganisms, including 60 bacteria and one Candida spp, isolated from clinical wound specimens from 32 patients. The most common isolates obtained were Streptococcus spp. (n=12), Peptoniphilus spp. (n=8), Staphylococcus aureus (n=7), Escherichia coli (n=7), and Klebsiella pneumoniae (n=7). Among 21 strains of gram-negative bacilli, five (23.8%) were resistant to fluoroquinolones, and three isolates were resistant to ceftriaxone. Two E. coli strains produced extended-spectrum beta-lactamase. Four of the seven S. aureus isolates were methicillin-resistant. Among 15 anaerobic isolates, nine (60%) were resistant to penicillin, and eight (53.3%) were resistant to clindamycin. Four (26.7%) isolates were resistant to metronidazole. The only independent risk factor associated with mortality was inappropriate initial antibiotic treatment (p=0.021). Antibiotic-resistant bacteria are emerging in the clinical setting of Fournier gangrene. Clinicians should use broad-spectrum antibiotics initially to cover possible antibiotic-resistant bacteria.

  13. Calcined Eggshell Waste for Mitigating Soil Antibiotic-Resistant Bacteria/Antibiotic Resistance Gene Dissemination and Accumulation in Bell Pepper.

    Science.gov (United States)

    Ye, Mao; Sun, Mingming; Feng, Yanfang; Li, Xu; Schwab, Arthur P; Wan, Jinzhong; Liu, Manqiang; Tian, Da; Liu, Kuan; Wu, Jun; Jiang, Xin

    2016-07-13

    The combined accumulation of antibiotics, heavy metals, antibiotic-resistant bacteria (ARB)/antibiotic resistance genes (ARGs) in vegetables has become a new threat to human health. This is the first study to investigate the feasibility of calcined eggshells modified by aluminum sulfate as novel agricultural wastes to impede mixed contaminants from transferring to bell pepper (Capsicum annuum L.). In this work, calcined eggshell amendment mitigated mixed pollutant accumulation in bell pepper significantly, enhanced the dissipation of soil tetracycline, sulfadiazine, roxithromycin, and chloramphenicol, decreased the water-soluble fractions of antibiotics, and declined the diversity of ARB/ARGs inside the vegetable. Moreover, quantitative polymerase chain reaction analysis detected that ARG levels in the bell pepper fruits significantly decreased to 10(-10) copies/16S copies, indicating limited risk of ARGs transferring along the food chain. Furthermore, the restoration of soil microbial biological function suggests that calcined eggshell is an environmentally friendly amendment to control the dissemination of soil ARB/ARGs in the soil-vegetable system.

  14. Antibiotics resistance phenomenon and virulence ability in bacteria from water environment

    Directory of Open Access Journals (Sweden)

    Mohamed I. Azzam

    2017-10-01

    Full Text Available This study aims to determine the impact of five main drains as sources of antibiotics resistant bacteria in River Nile at Rosetta branch, and to generate a baseline data on their virulence ability. Out of 212 bacterial isolates, 39.2% and 60.8% were recovered from drains and Rosetta branch, respectively. Susceptibility of bacteria to different antibiotics showed multiple antibiotics resistances (MAR for the majority of isolates. Meanwhile, sensitivity was mostly directed to ofloxacin and norfloxacin antibiotics. Calculated MAR index values (>0.25 classified area of study as potentially health risk environment. Testing virulence ability of bacteria from drains showed positive results (65%. Contrastively, virulent strains in Rosetta branch were mostly lacking in this study. Concluding remarks justify the strong correlation (r = +0.82 between MAR and virulence of bacteria in polluted aquatic ecosystems, and highlight the potential of drains as reactors for their amplification and dissemination. The study suggests regular monitoring for antibiotics resistance in native bacteria of River Nile, prohibition of unregulated use of antibiotics, and proper management for wastes disposal.

  15. [Antibiotic resistance--an ambivalence of attitudes. As of now, the bacteria are in advantage].

    Science.gov (United States)

    Sköld, O

    1995-09-13

    The value of the precious medical asset that antibiotics constitute is contimualby being eroded by the spread of resistance. For some time that bacterial world has been adapting itself to contend with the toxic assault of man-made poisons, antibiotics, by developing resistance in a very rapid process of evolutionary changes occurring before our very eyes. This evolutionary adaptation is an example of natural genetic engineering entailing an interchange between bacteria of genes conferring antibiotic resistance. Trimethoprim resistance is an example where numerous genes of unknown origin (some closely interrelated), expressing drug-resistant dihydrofolate reductases, move among human commensals and pathogens. They have been shown to move as gene cassettes in and out of the recently characterised integron structure occurring in many pathogens. They are also carried by various transposons such as Tn7, or Tn5393 originally observed in a plant pathogen, Erwinia amylovora. Betalactam resistance is another example of natural genetic engineering, where new betalactamases are continually emerging, and individual enzyme substrate specificity is modified by point mutation. At present, betalactamase mutants resistant to all commercially available betalactams, including clavulanic acid used in combination with betalactam antibiotics, are to be found in clinical isolates. Thus, currently bacteria seem to be triumphing in the running battle between the pharmaceutical industry and the bacterial world, the former introducing one new antibiotic variant after another, to which bacteria promptly develop resistance by manipulating their own genomes.

  16. Reusing Treated Wastewater: Consideration of the Safety Aspects Associated with Antibiotic-Resistant Bacteria and Antibiotic Resistance Genes

    Directory of Open Access Journals (Sweden)

    Pei-Ying Hong

    2018-02-01

    Full Text Available As more countries engage in water reuse, either intended or de facto, there is an urgent need to more comprehensively evaluate resulting environmental and public health concerns. While antibiotic-resistant bacteria (ARB and antibiotic resistance genes (ARGs are increasingly coming under the spotlight, as emerging contaminants, existing water reuse regulations and guidelines do not adequately address these concerns. This perspectives paper seeks to frame the various challenges that need to be resolved to identify meaningful and realistic target types and levels of antibiotic resistance benchmarks for water reuse. First, there is the need for standardized and agreed-upon methodologies to identify and quantify ARB and ARGs. Second, even if methodologies are available, identifying which ARB and ARGs to monitor that would best relate to the occurrence of disease burden remains unknown. Third, a framework tailored to assessing the risks associated with ARB and ARGs during reuse is urgently needed. Fourth, similar to protecting drinking water sources, strategies to prevent dissemination of ARB and ARGs via wastewater treatment and reuse are required to ensure that appropriate barriers are emplaced. Finally, current wastewater treatment technologies could benefit from modification or retrofit to more effectively remove ARB and ARGs while also producing a high quality product for water and resource recovery. This perspectives paper highlights the need to consider ARB and ARGs when evaluating the overall safety aspects of water reuse and ways by which this may be accomplished.

  17. Reusing Treated Wastewater: Consideration of the Safety Aspects Associated with Antibiotic-Resistant Bacteria and Antibiotic Resistance Genes

    KAUST Repository

    Hong, Pei-Ying

    2018-02-27

    As more countries engage in water reuse, either intended or de facto, there is an urgent need to more comprehensively evaluate resulting environmental and public health concerns. While antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) are increasingly coming under the spotlight, as emerging contaminants, existing water reuse regulations and guidelines do not adequately address these concerns. This perspectives paper seeks to frame the various challenges that need to be resolved to identify meaningful and realistic target types and levels of antibiotic resistance benchmarks for water reuse. First, there is the need for standardized and agreed-upon methodologies to identify and quantify ARB and ARGs. Second, even if methodologies are available, identifying which ARB and ARGs to monitor that would best relate to the occurrence of disease burden remains unknown. Third, a framework tailored to assessing the risks associated with ARB and ARGs during reuse is urgently needed. Fourth, similar to protecting drinking water sources, strategies to prevent dissemination of ARB and ARGs via wastewater treatment and reuse are required to ensure that appropriate barriers are emplaced. Finally, current wastewater treatment technologies could benefit from modification or retrofit to more effectively remove ARB and ARGs while also producing a high quality product for water and resource recovery. This perspectives paper highlights the need to consider ARB and ARGs when evaluating the overall safety aspects of water reuse and ways by which this may be accomplished.

  18. Anaerobic bacteria and antibiotics: What kind of unexpected resistance could I find in my laboratory tomorrow?

    Science.gov (United States)

    Dubreuil, L; Odou, M F

    2010-12-01

    The purpose of this article is to set out some important considerations on the main emerging antibiotic resistance patterns among anaerobic bacteria. The first point concerns the Bacteroides fragilis group and its resistance to the combination of β-lactam+β-lactamase inhibitor. When there is overproduction of cephalosporinase, it results in increased resistance to the β-lactams while maintaining susceptibility to β-lactams/β-lactamase inhibitor combinations. However, if another resistance mechanism is added, such as a loss of porin, resistances to β-lactam+β-lactamase inhibitor combinations may occur. The second point is resistance to metronidazole occurring due to nim genes. PCR detection of nim genes alone is not sufficient for predicting resistance to metronidazole; actual MIC determinations are required. Therefore, it can be assumed that other resistance mechanisms can also be involved. Although metronidazole resistance remains rare for the B. fragilis group, it has nevertheless been detected worldwide and also been observed spreading to other species. In some cases where there is only a decreased susceptibility, clinical failures may occur. The last point concerns resistance of Clostridium species to glycopeptides and lipopeptides. Low levels of resistance have been detected with these antibiotics. Van genes have been detected not only in clostridia but also in other species. In conclusion, antibiotic resistance involves different mechanisms and affects many anaerobic species and is spreading worldwide. This demonstrates the need to continue with antibiotic resistance testing and surveys in anaerobic bacteria. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Heavy metal and antibiotic resistance in bacteria isolated from the environment of swine farms

    International Nuclear Information System (INIS)

    Fan, Y.; Ping, C.; Mei, L.S.

    2014-01-01

    The aim of the present study was to determine the level of heavy metal resistance and antibiotic resistance patterns of bacterial isolates from environment of swine farms in China. A total of 284 bacteria were isolated, 158 from manure, 62 from soil and 64 from wastewater in different swine farm samples. All the isolates were tested for resistant against eight heavy metals. From the total of 284 isolates, maximum bacterial isolates were found to be resistant to Zn/sup 2+/ (98.6%) followed by Cu/sup 2+/ (97.5%), Cd/sup 2+/ (68.3%), Mn/sup 2+/ (60.2%), Pb/sup 2+/(51.4%), Ni/sup 2+/(41.5%) and Cr/sup 2+/(45.1%). However, most of the isolates were sensitive to Co/sup 2+/. Meanwhile,all the isolates were tested for sensitively to nine antibiotics. The results shows that most isolates were sensitive to cefoxitin and oxacillin, but resistance to tetracycline, ampicillin, gentamicin, amikacin, erythromycin, clindamycin were widespread. Multiple resistant to metals and antibiotics were also observed in this study. Most isolates were tolerant to different concentrations of various heavy metals and antibiotics. Our results confirmed that environment of swine farms in China has a significant proportion of heavy metal and antibiotic resistant bacteria, and these bacteria constitute a potential risk for swine health and public health. (author)

  20. Antibiotic Resistant Bacteria And Their Associated Resistance Genes in a Conventional Municipal Wastewater Treatment Plant

    KAUST Repository

    Aljassim, Nada I.

    2013-12-01

    With water scarcity as a pressing issue in Saudi Arabia and other Middle Eastern countries, the treatment and reuse of municipal wastewater is increasingly being used as an alternative water source to supplement country water needs. Standards are in place to ensure a safe treated wastewater quality, however they do not regulate pathogenic bacteria and emerging contaminants. Information is lacking on the levels of risk to public health associated with these factors, the efficiency of conventional treatment strategies in removing them, and on wastewater treatment in Saudi Arabia in general. In this study, a municipal wastewater treatment plant in Saudi Arabia is investigated to assess the efficiency of conventional treatment in meeting regulations and removing pathogens and emerging contaminants. The study found pathogenic bacterial genera, antibiotic resistance genes and antibiotic resistant bacteria, many of which were multi-resistant in plant discharges. It was found that although the treatments are able to meet traditional quality guidelines, there remains a risk from the discussed contaminants with wastewater reuse. A deeper understanding of this risk, and suggestions for more thorough guidelines and monitoring are needed.

  1. Impact of manure fertilization on the abundance of antibiotic-resistant bacteria and frequency of detection of antibiotic resistance genes in soil and on vegetables at harvest.

    Science.gov (United States)

    Marti, Romain; Scott, Andrew; Tien, Yuan-Ching; Murray, Roger; Sabourin, Lyne; Zhang, Yun; Topp, Edward

    2013-09-01

    Consumption of vegetables represents a route of direct human exposure to bacteria found in soil. The present study evaluated the complement of bacteria resistant to various antibiotics on vegetables often eaten raw (tomato, cucumber, pepper, carrot, radish, lettuce) and how this might vary with growth in soil fertilized inorganically or with dairy or swine manure. Vegetables were sown into field plots immediately following fertilization and harvested when of marketable quality. Vegetable and soil samples were evaluated for viable antibiotic-resistant bacteria by plate count on Chromocult medium supplemented with antibiotics at clinical breakpoint concentrations. DNA was extracted from soil and vegetables and evaluated by PCR for the presence of 46 gene targets associated with plasmid incompatibility groups, integrons, or antibiotic resistance genes. Soil receiving manure was enriched in antibiotic-resistant bacteria and various antibiotic resistance determinants. There was no coherent corresponding increase in the abundance of antibiotic-resistant bacteria enumerated from any vegetable grown in manure-fertilized soil. Numerous antibiotic resistance determinants were detected in DNA extracted from vegetables grown in unmanured soil. A smaller number of determinants were additionally detected on vegetables grown only in manured and not in unmanured soil. Overall, consumption of raw vegetables represents a route of human exposure to antibiotic-resistant bacteria and resistance determinants naturally present in soil. However, the detection of some determinants on vegetables grown only in freshly manured soil reinforces the advisability of pretreating manure through composting or other stabilization processes or mandating offset times between manuring and harvesting vegetables for human consumption.

  2. Antibiotic Resistance Pattern of Bacteria Causing Urinary Tract Infections in Children of Fasa During the years 2012 and 2014

    Directory of Open Access Journals (Sweden)

    alireza molazade

    2015-02-01

    Conclusion: Regarding the results, it is recommended to use Ciprofloxacin and Nitrofurantoin for outpatient treatment of UTI. Selecting proper antibiotics for UTI treatment should be on the basis of the local prevalence of pathogenic bacteria and antibiotic resistance pattern.

  3. Antibiotic resistance in bacteria Staphylococcus spp. isolated from samples of raw sheep's milk

    Directory of Open Access Journals (Sweden)

    Milan Vasiľ

    2016-12-01

    Full Text Available From samples of raw sheep's milk were determined results of bacteriological examination from two herds in region of Eastern Slovakia in three years lasting study. The occurrence of Staphylococcus spp. 41.6% (124 was determined from 298 samples. The seven species of staphylococci were on a regular basis isolated: S. epidermidis (34, S. chromogenes (26, S. aureus (16. Alternately have been recorded S. warneri (16, S. schleiferi (15, S. haemolyticus (9 and S. xylosus (8. All isolated pathogens were tested by in vitro test on Mueller-Hinton agar by disc methods on resistance to 10 types of antibiotics.  Highest value of resistance was determined to Penicilin 21.0%, Neomycin 10.5% and Novobiocin 9.7%. Lower resistance was in to Oxacilin 7.2% and Amoxicilin 6.5%. Minimal resistance was founded to Cefoxitin 0.8%, Linkomycin 2.4%, Erytromycin, and Streptomycin 3.2%. Was founded total resistance (21.0% to all antibiotics in S. epidermidis (34 during the three years, S. chromogenes (26 showed resistance to 8 types of antibiotics (12.9%, S. aureus (16 to 6 antibiotics (10.5% and S. warneri (16 to 4 antibiotics (5.6%. It was confirmed that sheep's milk remains a major source of staphylococci. Bacteria in comparison with isolates from cows' raw milk, showed lower values of resistance, but were resistant to more than two antibiotics. Recorded occurrence of resistance in staphylococci may be connected with a minimum use of antibiotics in the treatment of mastitis and other diseases in sheep herds. Reported resistance to the tested antibiotics became the basis for the recommendation to use preparations to treat mastitis in sheep principally by the detection of resistance to antibiotics contained.

  4. A WWW-based information system on resistance of bacteria to antibiotics.

    Science.gov (United States)

    Schindler, J; Schindler, Z; Schindler, J

    1998-01-01

    The information system on resistance of bacteria to antibiotics (WARN--World Antibiotic Resistance Network) is implemented as a WWW server at Charles University in Prague (http:/(/)www.warn.cas.cz). Its main goal is to give information about problems of antibiotic resistance of bacteria and to process data on isolated strains. The WARN web-site contains six main topics. Four of them form the core of the system: Topics of Interest bring information on selected timely topics in antibiotic resistance--pneumococci, staphylococci, beta-lactamases, glycopeptide--and aminoglycoside resistance. Global Monitor brings references and reports on resistance in the world as well as recommended method of surveillance. The topic Data contains raw data on strains in particular countries and hospitals. Data can be viewed in their original form as a list of records (strains) or processed to provide statistics about the resistance rates in the selected country or hospital respectively. The topic Search allows one to search for one or several terms in the whole document. Counts of accessed pages show, that there is a standing demand for information about the serious problems of antibiotic therapy of infectious diseases.

  5. Survival of Antibiotic Resistant Bacteria and Horizontal Gene Transfer Control Antibiotic Resistance Gene Content in Anaerobic Digesters.

    Science.gov (United States)

    Miller, Jennifer H; Novak, John T; Knocke, William R; Pruden, Amy

    2016-01-01

    Understanding fate of antibiotic resistant bacteria (ARB) vs. their antibiotic resistance genes (ARGs) during wastewater sludge treatment is critical in order to reduce the spread of antibiotic resistance through process optimization. Here, we spiked high concentrations of tetracycline-resistant bacteria, isolated from mesophilic (Iso M1-1-a Pseudomonas sp.) and thermophilic (Iso T10-a Bacillus sp.) anaerobic digested sludge, into batch digesters and monitored their fate by plate counts and quantitative polymerase chain reaction (QPCR) of their corresponding tetracycline ARGs. In batch studies, spiked ARB plate counts returned to baseline (thermophilic) or 1-log above baseline (mesophilic) while levels of the ARG present in the spiked isolate [tet(G)] remained high in mesophilic batch reactors. To compare results under semi-continuous flow conditions with natural influent variation, tet(O), tet(W), and sul1 ARGs, along with the intI1 integrase gene, were monitored over a 9-month period in the raw feed sludge and effluent sludge of lab-scale thermophilic and mesophilic anaerobic digesters. sul1 and intI1 in mesophilic and thermophilic digesters correlated positively (Spearman rho = 0.457-0.829, P < 0.05) with the raw feed sludge. There was no correlation in tet(O) or tet(W) ratios in raw sludge and mesophilic digested sludge or thermophilic digested sludge (Spearman rho = 0.130-0.486, P = 0.075-0.612). However, in the thermophilic digester, the tet(O) and tet(W) ratios remained consistently low over the entire monitoring period. We conclude that the influent sludge microbial composition can influence the ARG content of a digester, apparently as a result of differential survival or death of ARBs or horizontal gene transfer of genes between raw sludge ARBs and the digester microbial community. Notably, mesophilic digestion was more susceptible to ARG intrusion than thermophilic digestion, which may be attributed to a higher rate of ARB survival and/or horizontal gene

  6. Prevalence of antibiotic-resistant Gram-negative bacteria associated with the red-eared slider (Trachemys scripta elegans).

    Science.gov (United States)

    Liu, Dandan; Wilson, Cailin; Hearlson, Jodie; Singleton, Jennifer; Thomas, R Brent; Crupper, Scott S

    2013-09-01

    Free-ranging Red-eared Sliders (Trachemys scripta elegans) were captured from farm ponds located in the Flint Hills of Kansas and a zoo pond in Emporia, Kansas, USA, to evaluate their enteric bacterial flora and associated antibiotic resistance. Bacteria obtained from cloacal swabs were composed of six different Gram-negative genera. Although antibiotic resistance was present in turtles captured from both locations, 40 and 49% of bacteria demonstrated multiple antibiotic resistance to four of the antibiotics tested from the zoo captured and Flint Hills ponds turtles, respectively. These data illustrate environmental antibiotic resistance is widespread in the bacterial flora obtained from Red-eared Sliders in east central Kansas.

  7. [Distribution and removal of anaerobic antibiotic resistant bacteria during mesophilic anaerobic digestion of sewage sludge].

    Science.gov (United States)

    Tong, Juan; Wang, Yuan-Yue; Wei Yuan, Song

    2014-10-01

    Sewage sludge is one of the major sources that releasing antibiotic resistant bacteria (ARB) and antibiotic resistant genes (ARG) into the environment since it contains large amount of ARB, but there is little information about the fate of the anaerobic ARB in the anaerobic digestion of sewage sludge. Therefore, the distribution, removal and seasonal changes of tetracycline and β-lactam antibiotics resistant bacteria in the mesophilic egg-shaped digesters of a municipal wastewater treatment plant were investigated for one year in this study. Results showed that there were higher amounts of ARB and higher resistance rate of β-lactam antibiotics than that of tetracycline antibiotics in the sewage sludge. All ARB could be significantly reduced during the mesophilic anaerobic digestion process by 1.48-1.64 log unit (P anaerobic digestion by 12.0% and 14.3%, respectively (P bacteria, there were more ARB in the sewage sludge in cold season than in warm season (P < 0.05).

  8. Tracking acquired antibiotic resistance in commensal bacteria of Galápagos land iguanas: no man, no resistance.

    Science.gov (United States)

    Thaller, Maria Cristina; Migliore, Luciana; Marquez, Cruz; Tapia, Washington; Cedeño, Virna; Rossolini, Gian Maria; Gentile, Gabriele

    2010-02-01

    Antibiotic resistance, evolving and spreading among bacterial pathogens, poses a serious threat to human health. Antibiotic use for clinical, veterinary and agricultural practices provides the major selective pressure for emergence and persistence of acquired resistance determinants. However, resistance has also been found in the absence of antibiotic exposure, such as in bacteria from wildlife, raising a question about the mechanisms of emergence and persistence of resistant strains under similar conditions, and the implications for resistance control strategies. Since previous studies yielded some contrasting results, possibly due to differences in the ecological landscapes of the studied wildlife, we further investigated this issue in wildlife from a remote setting of the Galapagos archipelago. Screening for acquired antibiotic resistance was carried out in commensal enterobacteria from Conolophus pallidus, the terrestrial iguana of Isla Santa Fe, where: i) the abiotic conditions ensure to microbes good survival possibilities in the environment; ii) the animal density and their habits favour microbial circulation between individuals; and iii) there is no history of antibiotic exposure and the impact of humans and introduced animal species is minimal except for restricted areas. Results revealed that acquired antibiotic resistance traits were exceedingly rare among bacteria, occurring only as non-dominant strains from an area of minor human impact. Where both the exposure to antibiotics and the anthropic pressure are minimal, acquired antibiotic resistance traits are not normally found in bacteria from wildlife, even if the ecological landscape is highly favourable to bacterial circulation among animals. Monitoring antibiotic resistance in wildlife from remote areas could also be a useful tool to evaluate the impact of anthropic pressure.

  9. Tracking acquired antibiotic resistance in commensal bacteria of Galápagos land iguanas: no man, no resistance.

    Directory of Open Access Journals (Sweden)

    Maria Cristina Thaller

    Full Text Available BACKGROUND: Antibiotic resistance, evolving and spreading among bacterial pathogens, poses a serious threat to human health. Antibiotic use for clinical, veterinary and agricultural practices provides the major selective pressure for emergence and persistence of acquired resistance determinants. However, resistance has also been found in the absence of antibiotic exposure, such as in bacteria from wildlife, raising a question about the mechanisms of emergence and persistence of resistant strains under similar conditions, and the implications for resistance control strategies. Since previous studies yielded some contrasting results, possibly due to differences in the ecological landscapes of the studied wildlife, we further investigated this issue in wildlife from a remote setting of the Galapagos archipelago. METHODOLOGY/PRINCIPAL FINDINGS: Screening for acquired antibiotic resistance was carried out in commensal enterobacteria from Conolophus pallidus, the terrestrial iguana of Isla Santa Fe, where: i the abiotic conditions ensure to microbes good survival possibilities in the environment; ii the animal density and their habits favour microbial circulation between individuals; and iii there is no history of antibiotic exposure and the impact of humans and introduced animal species is minimal except for restricted areas. Results revealed that acquired antibiotic resistance traits were exceedingly rare among bacteria, occurring only as non-dominant strains from an area of minor human impact. CONCLUSIONS/SIGNIFICANCE: Where both the exposure to antibiotics and the anthropic pressure are minimal, acquired antibiotic resistance traits are not normally found in bacteria from wildlife, even if the ecological landscape is highly favourable to bacterial circulation among animals. Monitoring antibiotic resistance in wildlife from remote areas could also be a useful tool to evaluate the impact of anthropic pressure.

  10. Frequency and antibiotic resistance patterns of isolated bacteria from positive blood culture of hospitalized patients

    Directory of Open Access Journals (Sweden)

    Azadeh Vahedi

    2018-03-01

    Conclusion: The most prevalent bacterial isolate among the blood cultures of patients was Pseudomonas. The patients more than 50 years were more susceptible to blood stream infections. The most bacteria were isolated from the internal medicine department of hospital. The antibiotic resistance was also increasing especially in Acinetobacter, Staphylococcus coagulase negative, Escherichia coil and Klebsiella

  11. Occurrence and Distribution of Antibiotic-resistant Bacteria and Transfer of Resistance Genes in Lake Taihu

    OpenAIRE

    Yin, Qian; Yue, Dongmei; Peng, Yuke; Liu, Ying; Xiao, Lin

    2013-01-01

    The overuse of antibiotics has accelerated antibiotic resistance in the natural environment, especially fresh water, generating a potential risk for public health around the world. In this study, antibiotic resistance in Lake Taihu was investigated and this was the first thorough data obtained through culture-dependent methods. High percentages of resistance to streptomycin and ampicillin among bacterial isolates were detected, followed by tetracycline and chloramphenicol. Especially high lev...

  12. Removal of antibiotic-resistant bacteria and antibiotic resistance genes affected by varying degrees of fouling on anaerobic microfiltration membranes

    KAUST Repository

    Cheng, Hong; Hong, Pei-Ying

    2017-01-01

    An anaerobic membrane bioreactor was retrofitted with polyvinylidene fluoride (PVDF) microfiltration membrane units, each of which was fouled to a different extent. The membranes with different degrees of fouling were evaluated for their efficiencies in removing three antibiotic-resistant bacteria (ARB), namely, blaNDM-1-positive Escherichia coli PI-7, blaCTX-M-15-positive Klebsiella pneumoniae L7, and blaOXA-48-positive E. coli UPEC-RIY-4, as well as their associated plasmid-borne antibiotic resistance genes (ARGs). The results showed that the log removal values (LRVs) of ARGs correlated positively with the extent of membrane fouling and ranged from 1.9 to 3.9. New membranes with a minimal foulant layer could remove more than 5 log units of ARB. However, as the membranes progressed to subcritical fouling, the LRVs of ARB decreased at increasing operating transmembrane pressures (TMPs). The LRV recovered back to 5 when the membrane was critically fouled, and the achieved LRV remained stable at different operating TMPs. Furthermore, characterization of the surface attributed the removal of both the ARB and ARGs to adsorption, which was facilitated by an increasing hydrophobicity and a decreasing surface ζ potential as the membranes fouled. Our results indicate that both the TMP and the foulant layer synergistically affected ARB removal, but the foulant layer was the main factor that contributed to ARG removal.

  13. Removal of antibiotic-resistant bacteria and antibiotic resistance genes affected by varying degrees of fouling on anaerobic microfiltration membranes

    KAUST Repository

    Cheng, Hong

    2017-09-28

    An anaerobic membrane bioreactor was retrofitted with polyvinylidene fluoride (PVDF) microfiltration membrane units, each of which was fouled to a different extent. The membranes with different degrees of fouling were evaluated for their efficiencies in removing three antibiotic-resistant bacteria (ARB), namely, blaNDM-1-positive Escherichia coli PI-7, blaCTX-M-15-positive Klebsiella pneumoniae L7, and blaOXA-48-positive E. coli UPEC-RIY-4, as well as their associated plasmid-borne antibiotic resistance genes (ARGs). The results showed that the log removal values (LRVs) of ARGs correlated positively with the extent of membrane fouling and ranged from 1.9 to 3.9. New membranes with a minimal foulant layer could remove more than 5 log units of ARB. However, as the membranes progressed to subcritical fouling, the LRVs of ARB decreased at increasing operating transmembrane pressures (TMPs). The LRV recovered back to 5 when the membrane was critically fouled, and the achieved LRV remained stable at different operating TMPs. Furthermore, characterization of the surface attributed the removal of both the ARB and ARGs to adsorption, which was facilitated by an increasing hydrophobicity and a decreasing surface ζ potential as the membranes fouled. Our results indicate that both the TMP and the foulant layer synergistically affected ARB removal, but the foulant layer was the main factor that contributed to ARG removal.

  14. Removal of Antibiotic-Resistant Bacteria and Antibiotic Resistance Genes Affected by Varying Degrees of Fouling on Anaerobic Microfiltration Membranes.

    Science.gov (United States)

    Cheng, Hong; Hong, Pei-Ying

    2017-11-07

    An anaerobic membrane bioreactor was retrofitted with polyvinylidene fluoride (PVDF) microfiltration membrane units, each of which was fouled to a different extent. The membranes with different degrees of fouling were evaluated for their efficiencies in removing three antibiotic-resistant bacteria (ARB), namely, bla NDM-1 -positive Escherichia coli PI-7, bla CTX-M-15 -positive Klebsiella pneumoniae L7, and bla OXA-48 -positive E. coli UPEC-RIY-4, as well as their associated plasmid-borne antibiotic resistance genes (ARGs). The results showed that the log removal values (LRVs) of ARGs correlated positively with the extent of membrane fouling and ranged from 1.9 to 3.9. New membranes with a minimal foulant layer could remove more than 5 log units of ARB. However, as the membranes progressed to subcritical fouling, the LRVs of ARB decreased at increasing operating transmembrane pressures (TMPs). The LRV recovered back to 5 when the membrane was critically fouled, and the achieved LRV remained stable at different operating TMPs. Furthermore, characterization of the surface attributed the removal of both the ARB and ARGs to adsorption, which was facilitated by an increasing hydrophobicity and a decreasing surface ζ potential as the membranes fouled. Our results indicate that both the TMP and the foulant layer synergistically affected ARB removal, but the foulant layer was the main factor that contributed to ARG removal.

  15. Re-sensitizing drug-resistant bacteria to antibiotics by designing Antisense Therapeutics

    Science.gov (United States)

    Courtney, Colleen; Chatterjee, Anushree

    2014-03-01

    ``Super-bugs'' or ``multi-drug resistant organisms'' are a serious international health problem, with devastating consequences to patient health care. The Center for Disease Control has identified antibiotic resistance as one of the world's most pressing public health problems as a significant fraction of bacterial infections contracted are drug resistant. Typically, antibiotic resistance is encoded by ``resistance-genes'' which express proteins that carryout the resistance causing functions inside the bacterium. We present a RNA based therapeutic strategy for designing antimicrobials capable of re-sensitizing resistant bacteria to antibiotics by targeting labile regions of messenger RNAs encoding for resistance-causing proteins. We perform in silico RNA secondary structure modeling to identify labile target regions in an mRNA of interest. A synthetic biology approach is then used to administer antisense nucleic acids to our model system of ampicillin resistant Escherichia coli. Our results show a prolonged lag phase and decrease in viability of drug-resistant E. colitreated with antisense molecules. The antisense strategy can be applied to alter expression of other genes in antibiotic resistance pathways or other pathways of interest.

  16. Levels and treatment options for enteric and antibiotic resistant bacteria in sewage from Sisimiut, Greenland

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Gunnarsdottir, Ragnhildur; Andersen, Henrik Rasmus

    2013-01-01

    Sewage treatment in Arctic towns is inadequate. Sewage contains pathogenic microorganisms, parasites, antibiotic resistant bacteria, and toxic compounds. Discharging of untreated sewage can thus have a negative effect on people’s health and the aquatic environment in the receiving water bodies....... Conventional treatment is challenging and expensive to implement in Arctic communities due to the cold climate and scattered population. In addition, advanced removal of nutrients may in many cases be overstated due to the low population density and large receiving water bodies. In this work we investigated......, the wastewater is very strong, suggesting a potential hygienic risk. In addition, a high fraction of antibiotic resistant bacteria and an increased toxicity in the sub-stream from the hospital, suggest that this stream contains toxic compounds, possibly antibiotic of nature that may affect the local Arctic...

  17. Occurrence and Distribution of Antibiotic-resistant Bacteria and Transfer of Resistance Genes in Lake Taihu

    Science.gov (United States)

    Yin, Qian; Yue, Dongmei; Peng, Yuke; Liu, Ying; Xiao, Lin

    2013-01-01

    The overuse of antibiotics has accelerated antibiotic resistance in the natural environment, especially fresh water, generating a potential risk for public health around the world. In this study, antibiotic resistance in Lake Taihu was investigated and this was the first thorough data obtained through culture-dependent methods. High percentages of resistance to streptomycin and ampicillin among bacterial isolates were detected, followed by tetracycline and chloramphenicol. Especially high levels of ampicillin resistance in the western and northern regions were illustrated. Bacterial identification of the isolates selected for further study indicated the prevalence of some opportunistic pathogens and 62.0% of the 78 isolates exhibited multiple antibiotic resistance. The presence of ESBLs genes was in the following sequence: blaTEM > blaSHV > blaCTMX and 38.5% of the isolates had a class I integrase gene. Of all tested strains, 80.8% were able to transfer antibiotic resistance through conjugation. We also concluded that some new families of human-associated ESBLs and AmpC genes can be found in natural environmental isolates. The prevalence of antibiotic resistance and the dissemination of transferable antibiotic resistance in bacterial isolates (especially in opportunistic pathogens) was alarming and clearly indicated the urgency of realizing the health risks of antibiotic resistance to human and animal populations who are dependent on Lake Taihu for water consumption. PMID:24240317

  18. Assessment of Antibiotic Resistant Commensal Bacteria in Food

    Science.gov (United States)

    2006-01-01

    mold Penicillium was able to inhibit the growth of some bacteria. (37). In 1928, a Brittish physician Alexander Fleming observed the similar...phenomenon. One of his bacterial plate cultures was contaminated with the blue-green mold Penicillium , and the bacterial colonies in close approximation to...sliced chicken lunchmeat, and the strain was identified as Pseudomonas sp . ART bacteria were isolated sporadically in 32 lunchmeat, which is

  19. ANTIBIOTIC RESISTANCE IN LACTIC ACID BACTERIA ISOLATED FROM FERMENTED DAIRY PRODUCTS AND BOZA

    Directory of Open Access Journals (Sweden)

    Gamze Başbülbül

    2015-06-01

    Full Text Available In this study, the resistance of 83 strains of lactic acid bacteria isolated from Turkish cheese, yogurt, kefir and boza samples to 6 antibiotics (gentamicin, tetracycline, chloramphenicol, erythromycin, vancomycin and ciprofloxacin was evaluated. The 83 isolates were identified by 16S rRNA gene sequencing and according to BLAST comparisons with sequences in the data banks, those strains showing the highest similarities with the isolates were Enterococcus faecium (10, Lactococcus lactis subsp. Lactis (10, Lactobacillus fermentum (6, Lactobacillus plantarum (6, Lactobacillus coryniformis (7, Lactobacillus casei (13, Leuconostoc mesenteroides (14, Pediococcus pentosaceus (10, Weisella confusa (7. Antimicrobial resistance of strains to 6 antibiotics was determined using the agar dilution method. The antibiotic resistance among all the isolates was detected against chloramphenicol (31,3 % of the isolates, tetracycline (30,1 %, erythromycin (2,4 %, ciprofloxacin (2,41%, vancomycin (73,5 %, intrinsic resistance. Overall 19,3 % of the isolates showed resistance against multiple antibiotics. Antibiotic resistance genes were studied by PCR and the following genes were detected; tet(M gene in Lactobacillus fermentum (1, Lactobacillus plantarum (1, Pediococcus pentosaceus (5, Enterococcus faecium (2, Weisella confusa (4 and the vancomycin resistance gene van(A in one Weisella confusa strain.

  20. High prevalence of antibiotic resistance among bacteria isolated ...

    African Journals Online (AJOL)

    Mid-stream urine was collected and subjected to rapid dipstick and urine culture media. Antibacterial susceptibility tests were conducted against the bacteria. Risk factors for AUTI and demographic data were obtained using pretested questionnaire. Data were analyzed using SPSS Vs. 20 software package. Results: Of the ...

  1. Determination of antibiotic resistance of lactic acid bacteria isolated from traditional Turkish fermented dairy products.

    Science.gov (United States)

    Erginkaya, Z; Turhan, E U; Tatlı, D

    2018-01-01

    In this study, the antibiotic resistance (AR) of lactic acid bacteria (LAB) isolated from traditional Turkish fermented dairy products was investigated. Yogurt, white cheese, tulum cheese, cokelek, camız cream and kefir as dairy products were collected from various supermarkets. Lactic acid bacteria such as Lactobacillus spp., Streptococcus spp., Bifidobacterium spp., and Enterecoccus spp. were isolated from these dairy products. Lactobacillus spp. were resistant to vancomycin (58%), erythromycin (10.8%), tetracycline (4.3%), gentamicin (28%), and ciprofloxacin (26%). Streptococcus spp. were resistant to vancomycin (40%), erythromycin (10%), chloramphenicol (10%), gentamicin (20%), and ciprofloxacin (30%). Bifidobacterium spp. were resistant to vancomycin (60%), E 15 (6.6%), gentamicin (20%), and ciprofloxacin (33%). Enterococcus spp. were resistant to vancomycin (100%), erythromycin (100%), rifampin (100%), and ciprofloxacin (100%). As a result, LAB islated from dairy products in this study showed mostly resistance to vancomycin.

  2. Fate and transport of veterinary antibiotics, antibiotic-resistant bacteria, and antibiotic resistance gene from fields receiving poultry manure during storm events

    Science.gov (United States)

    Antimicrobials are used in production agriculture to treat disease and promote animal growth, but the presence of antibiotics in the environment raises concern about widespread antibiotic resistance. This study documents the occurrence and transport of tylosin, tetracycline, enterococci resistant to...

  3. Antibiotic resistance in bacteria isolated from vegetables with regards to the marketing stage (farm vs. supermarket).

    Science.gov (United States)

    Schwaiger, Karin; Helmke, Katharina; Hölzel, Christina Susanne; Bauer, Johann

    2011-08-15

    The aim of this study was to elucidate whether and to what extent fresh produce from Germany plays a role as a carrier and reservoir of antibiotic resistant bacteria. For this purpose, 1001 vegetables (fruit, root, bulbous vegetables, salads and cereals) were collected from 13 farms and 11 supermarkets in Germany and examined bacteriologically. Phenotypic resistance of Enterobacter cloacae (n=172); Enterobacter gergoviae (n=92); Pantoea agglomerans (n=96); Pseudomonas aeruginosa (n=295); Pseudomonas putida (n=106) and Enterococcus faecalis (n=100) against up to 30 antibiotics was determined by using the microdilution method. Resistance to ß-lactams was most frequently expressed by P. agglomerans and E. gergoviae against cefaclor (41% and 29%). Relatively high resistance rates were also observed for doxycycline (23%), erythromycin (21%) and rifampicin (65%) in E. faecalis, for spectinomycin (28%) and mezlocillin (12%) in E. cloacae, as well as for streptomycin (19%) in P. putida. In P. aeruginosa, relatively low resistance rates were observed for the aminoglycosides amikacin, apramicin, gentamicin, neomycin, netilmicin and tobramycin (bacteria isolated from farm samples were higher than those of the retail markets whenever significant differences were observed. This suggests that expressing resistance is at the expense of bacterial viability, since vegetables purchased directly at the farm are probably fresher than at the supermarket, and they have not been exposed to stress factors. However, this should not keep the customer from buying directly at the farm, since the overall resistance rates were not higher than observed in bacteria from human or animal origin. Instead, peeling or washing vegetables before eating them raw is highly recommended, since it reduces not only the risk of contact with pathogens, but also that of ingesting and spreading antibiotic resistant bacteria. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Metal and antibiotic resistance of bacteria isolated from the Baltic Sea.

    Science.gov (United States)

    Moskot, Marta; Kotlarska, Ewa; Jakóbkiewicz-Banecka, Joanna; Gabig-Cimińska, Magdalena; Fari, Karolina; Wegrzyn, Grzegorz; Wróbel, Borys

    2012-09-01

    The resistance of 49 strains of bacteria isolated from surface Baltic Sea waters to 11 antibiotics was analyzed and the resistance of selected strains to three metal ions (Ni2+, Mn2+, Zn2+) was tested. Most isolates belonged to Gammaproteobacteria (78%), while Alphaproteobacteria (8%), Actinobacteria (10%), and Bacteroidetes (4%) were less abundant. Even though previous reports suggested relationships between resistance and the presence of plasmids or the ability to produce pigments, no compelling evidence for such relationships was obtained for the strains isolated in this work. In particular, strains resistant to multiple antibiotics did not carry plasmids more frequently than sensitive strains. A relation between resistance and the four aminoglycosides tested (gentamycin, kanamycin, neomycin, and streptomycin), but not to spectinomycin, was demonstrated. This observation is of interest given that spectinomycin is not always classified as an aminoglycoside because it lacks a traditional sugar moiety. Statistical analysis indicated relationships between resistance to some antibiotics (ampicillin and erythromycin, chloramphenicol and erythromycin, chloramphenicol and tetracycline, erythromycin and tetracycline), suggesting the linkage of resistance genes for antibiotics belonging to different classes. The effects of NiSO4, ZnCl2 and MnCl2 on various media suggested that the composition of Marine Broth might result in low concentrations of Mn2+ due to chemical interactions that potentially lead to precipitation.

  5. Coevolution of antibiotic production and counter-resistance in soil bacteria.

    Science.gov (United States)

    Laskaris, Paris; Tolba, Sahar; Calvo-Bado, Leo; Wellington, Elizabeth M; Wellington, Liz

    2010-03-01

    We present evidence for the coexistence and coevolution of antibiotic resistance and biosynthesis genes in soil bacteria. The distribution of the streptomycin (strA) and viomycin (vph) resistance genes was examined in Streptomyces isolates. strA and vph were found either within a biosynthetic gene cluster or independently. Streptomyces griseus strains possessing the streptomycin cluster formed part of a clonal complex. All S. griseus strains possessing solely strA belonged to two clades; both were closely related to the streptomycin producers. Other more distantly related S. griseus strains did not contain strA. S. griseus strains with only vph also formed two clades, but they were more distantly related to the producers and to one another. The expression of the strA gene was constitutive in a resistance-only strain whereas streptomycin producers showed peak strA expression in late log phase that correlates with the switch on of streptomycin biosynthesis. While there is evidence that antibiotics have diverse roles in nature, our data clearly support the coevolution of resistance in the presence of antibiotic biosynthetic capability within closely related soil dwelling bacteria. This reinforces the view that, for some antibiotics at least, the primary role is one of antibiosis during competition in soil for resources.

  6. Incidence and transferability of antibiotic resistance in the enteric bacteria isolated from hospital wastewater

    Directory of Open Access Journals (Sweden)

    Mohammad Zubair Alam

    2013-09-01

    Full Text Available This study reports the occurrence of antibiotic resistance and production of β-lactamases including extended spectrum beta-lactamases (ESβL in enteric bacteria isolated from hospital wastewater. Among sixty-nine isolates, tested for antibiotic sensitivity, 73.9% strains were resistant to ampicillin followed by nalidixic acid (72.5%, penicillin (63.8%, co-trimoxazole (55.1%, norfloxacin (53.6%, methicillin (52.7%, cefuroxime (39.1%, cefotaxime (23.2% and cefixime (20.3%. Resistance to streptomycin, chloramphenicol, nitrofurantoin, tetracycline, and doxycycline was recorded in less than 13% of the strains. The minimum inhibitory concentration (MIC showed a high level of resistance (800-1600 µg/mL to one or more antibiotics. Sixty three (91% isolates produced β-lactamases as determined by rapid iodometric test. Multiple antibiotic resistances were noted in both among ESβL and non-ESβL producers. The β-lactamases hydrolyzed multiple substrates including penicillin (78.8% isolates, ampicillin (62.3%, cefodroxil (52.2%, cefotoxime (21.7% and cefuroxime (18.8%. Fifteen isolates producing ESβLs were found multidrug resistant. Four ESβL producing isolates could transfer their R-plasmid to the recipient strain E. coli K-12 with conjugation frequency ranging from 7.0 x 10-3 to 8.8 x 10-4. The findings indicated that ESβL producing enteric bacteria are common in the waste water. Such isolates may disseminate the multiple antibiotic resistance traits among bacterial community through genetic exchange mechanisms and thus requires immediate attention.

  7. Incidence and transferability of antibiotic resistance in the enteric bacteria isolated from hospital wastewater

    Science.gov (United States)

    Alam, Mohammad Zubair; Aqil, Farrukh; Ahmad, Iqbal; Ahmad, Shamim

    2013-01-01

    This study reports the occurrence of antibiotic resistance and production of β-lactamases including extended spectrum beta-lactamases (ESβL) in enteric bacteria isolated from hospital wastewater. Among sixty-nine isolates, tested for antibiotic sensitivity, 73.9% strains were resistant to ampicillin followed by nalidixic acid (72.5%), penicillin (63.8%), co-trimoxazole (55.1%), norfloxacin (53.6%), methicillin (52.7%), cefuroxime (39.1%), cefotaxime (23.2%) and cefixime (20.3%). Resistance to streptomycin, chloramphenicol, nitrofurantoin, tetracycline, and doxycycline was recorded in less than 13% of the strains. The minimum inhibitory concentration (MIC) showed a high level of resistance (800–1600 μg/mL) to one or more antibiotics. Sixty three (91%) isolates produced β-lactamases as determined by rapid iodometric test. Multiple antibiotic resistances were noted in both among ESβL and non-ESβL producers. The β-lactamases hydrolyzed multiple substrates including penicillin (78.8% isolates), ampicillin (62.3%), cefodroxil (52.2%), cefotoxime (21.7%) and cefuroxime (18.8%). Fifteen isolates producing ESβLs were found multidrug resistant. Four ESβL producing isolates could transfer their R-plasmid to the recipient strain E. coli K-12 with conjugation frequency ranging from 7.0 × 10−3 to 8.8 × 10−4. The findings indicated that ESβL producing enteric bacteria are common in the waste water. Such isolates may disseminate the multiple antibiotic resistance traits among bacterial community through genetic exchange mechanisms and thus requires immediate attention. PMID:24516448

  8. Synergistic effects of antimicrobial peptide DP7 combined with antibiotics against multidrug-resistant bacteria

    Directory of Open Access Journals (Sweden)

    Wu X

    2017-03-01

    Full Text Available Xiaozhe Wu,1 Zhan Li,1 Xiaolu Li,2,3 Yaomei Tian,1 Yingzi Fan,1 Chaoheng Yu,1 Bailing Zhou,1 Yi Liu,4 Rong Xiang,5 Li Yang1 1State Key Laboratory of Biotherapy/Collaborative Innovation Center of Biotherapy, West China Hospital, Sichuan University, 2International Center for Translational Chinese Medicine, Sichuan Academy of Chinese Medicine Sciences, Chengdu, 3Department of Plastic and Burn Surgery, Affiliated Hospital of Southwest Medical University, Luzhou, 4Department of Microbial Examination, Sichuan Center for Disease Control and Prevention, Chengdu, 5Nankai University School of Medicine, Tianjin, People’s Republic of China Abstract: Antibiotic-resistant bacteria present a great threat to public health. In this study, the synergistic effects of antimicrobial peptides (AMPs and antibiotics on several multidrug-resistant bacterial strains were studied, and their synergistic effects on azithromycin (AZT-resistance genes were analyzed to determine the relationships between antimicrobial resistance and these synergistic effects. A checkerboard method was used to evaluate the synergistic effects of AMPs (DP7 and CLS001 and several antibiotics (gentamicin, vancomycin [VAN], AZT, and amoxicillin on clinical bacterial strains (Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, and Escherichia coli. The AZT-resistance genes (ermA, ermB, ermC, mefA, and msrA were identified in the resistant strains using quantitative polymerase chain reaction. For all the clinical isolates tested that were resistant to different antibiotics, DP7 had high antimicrobial activity (≤32 mg/L. When DP7 was combined with VAN or AZT, the effect was most frequently synergistic. When we studied the resistance genes of the AZT-resistant isolates, the synergistic effect of DP7–AZT occurred most frequently in highly resistant strains or strains carrying more than two AZT-resistance genes. A transmission electron microscopic analysis of the S. aureus

  9. Prevalence of antibiotic resistance in bacteria isolated from drinking well water available in Guinea-Bissau (West Africa).

    Science.gov (United States)

    Machado, A; Bordalo, A A

    2014-08-01

    The dissemination of antibiotic-resistant bacteria and the spread of antibiotic resistance genes are a major public health concern worldwide, being even proposed as emerging contaminants. The aquatic environment is a recognized reservoir of antibiotic resistant bacteria, and antibiotic resistance genes have been recently detected in drinking water. In this study, the water quality and the prevalence of antibiotic resistance of heterotrophic culturable bacteria were characterized seasonally in wells that serve the population of Guinea-Bissau (West Africa) as the sole source of water for drinking and other domestic proposes. The results revealed that well water was unfit for human consumption independently of the season, owing to high acidity and heavy fecal contamination. Moreover, potentially pathogenic bacteria, which showed resistance to the most prescribed antibiotics in Guinea-Bissau, were isolated from well water, posing an additional health risk. Our results suggest that well water not only fosters the transmission of potential pathogenic bacteria, but also represents an important reservoir for the proliferation of antibiotic resistant bacteria, that can aggravate the potential to cause disease in a very vulnerable population that has no other alternative but to consume such water. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. The carriage of antibiotic resistance by enteric bacteria from imported tokay geckos (Gekko gecko) destined for the pet trade

    Energy Technology Data Exchange (ETDEWEB)

    Casey, Christine L. [Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602 (United States); Hernandez, Sonia M., E-mail: shernz@uga.edu [Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602 (United States); Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602 (United States); Yabsley, Michael J. [Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602 (United States); Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602 (United States); Smith, Katherine F. [Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912 (United States); Sanchez, Susan [The Athens Veterinary Diagnostic Laboratory, Athens, GA 30602 (United States); The Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602 (United States)

    2015-02-01

    The emergence of antibiotic-resistant bacteria is a growing public health concern and has serious implications for both human and veterinary medicine. The nature of the global economy encourages the movement of humans, livestock, produce, and wildlife, as well as their potentially antibiotic-resistant bacteria, across international borders. Humans and livestock can be reservoirs for antibiotic-resistant bacteria; however, little is known about the prevalence of antibiotic-resistant bacteria harbored by wildlife and, to our knowledge, limited data has been reported for wild-caught reptiles that were specifically collected for the pet trade. In the current study, we examined the antibiotic resistance of lactose-positive Enterobacteriaceae isolates from wild-caught Tokay geckos (Gekko gecko) imported from Indonesia for use in the pet trade. In addition, we proposed that the conditions under which wild animals are captured, transported, and handled might affect the shedding or fecal prevalence of antibiotic resistance. In particular we were interested in the effects of density; to address this, we experimentally modified densities of geckos after import and documented changes in antibiotic resistance patterns. The commensal enteric bacteria from Tokay geckos (G. gecko) imported for the pet trade displayed resistance against some antibiotics including: ampicillin, amoxicillin/clavulanic acid, cefoxitin, chloramphenicol, kanamycin and tetracycline. There was no significant difference in the prevalence of antibiotic-resistant bacteria after experimentally mimicking potentially stressful transportation conditions reptiles experience prior to purchase. There were, however, some interesting trends observed when comparing Tokay geckos housed individually and those housed in groups. Understanding the prevalence of antibiotic resistant commensal enteric flora from common pet reptiles is paramount because of the potential for humans exposed to these animals to acquire antibiotic-resistant

  11. The carriage of antibiotic resistance by enteric bacteria from imported tokay geckos (Gekko gecko) destined for the pet trade

    International Nuclear Information System (INIS)

    Casey, Christine L.; Hernandez, Sonia M.; Yabsley, Michael J.; Smith, Katherine F.; Sanchez, Susan

    2015-01-01

    The emergence of antibiotic-resistant bacteria is a growing public health concern and has serious implications for both human and veterinary medicine. The nature of the global economy encourages the movement of humans, livestock, produce, and wildlife, as well as their potentially antibiotic-resistant bacteria, across international borders. Humans and livestock can be reservoirs for antibiotic-resistant bacteria; however, little is known about the prevalence of antibiotic-resistant bacteria harbored by wildlife and, to our knowledge, limited data has been reported for wild-caught reptiles that were specifically collected for the pet trade. In the current study, we examined the antibiotic resistance of lactose-positive Enterobacteriaceae isolates from wild-caught Tokay geckos (Gekko gecko) imported from Indonesia for use in the pet trade. In addition, we proposed that the conditions under which wild animals are captured, transported, and handled might affect the shedding or fecal prevalence of antibiotic resistance. In particular we were interested in the effects of density; to address this, we experimentally modified densities of geckos after import and documented changes in antibiotic resistance patterns. The commensal enteric bacteria from Tokay geckos (G. gecko) imported for the pet trade displayed resistance against some antibiotics including: ampicillin, amoxicillin/clavulanic acid, cefoxitin, chloramphenicol, kanamycin and tetracycline. There was no significant difference in the prevalence of antibiotic-resistant bacteria after experimentally mimicking potentially stressful transportation conditions reptiles experience prior to purchase. There were, however, some interesting trends observed when comparing Tokay geckos housed individually and those housed in groups. Understanding the prevalence of antibiotic resistant commensal enteric flora from common pet reptiles is paramount because of the potential for humans exposed to these animals to acquire antibiotic-resistant

  12. [Identification of lactic acid bacteria in commercial yogurt and their antibiotic resistance].

    Science.gov (United States)

    Qin, Yuxuan; Li, Jing; Wang, Qiuya; Gao, Kexin; Zhu, Baoli; Lv, Na

    2013-08-04

    To identify lactic acid bacteria (LAB) in commercial yogurts and investigate their antibiotic resistance. LABs were cultured from 5 yogurt brands and the isolates were identified at the species level by 16S rRNA sequence. Genotyping was performed by repetitive extragenic palindromic PCR (rep-PCR). The sensitivity to 7 antibiotics was tested for all LAB isolates by Kirby-Bauer paper diffusion (K-B method). Meanwhile, 9 antibiotic resistance genes (ARGs), including erythromycin resistance genes (ermA and ermB) and tetracycline resistance genes (tetM, tetK, tetS, tetQ, tetO, tetL and tetW), were detected by PCR amplification in the identified LAB isolates. The PCR products were confirmed by sequencing. Total 100 LABs were isolated, including 23 Lactobacillus delbrueckii ssp. bulgaricus, 26 Lactobacillus casei, 30 Streptococcus thermophilus, 5 Lactobacillus acidophilus, 6 Lactobacillus plantarum, and 10 Lactobacillus paracasei. The drug susceptibility test shows that all 100 isolates were resistant to gentamicin and streptomycin, 42 isolates were resistant to vancomycin, and on the contrary all were sensitive to cefalexin, erythromycin, tetracycline and oxytetracycline. Moreover, 5 ARGs were found in the 28 sequencing confirmed isolates, ermB gene was detected in 8 isolates, tet K in 4 isolates, tetL in 2 isolates, tetM in 4 isolates, tetO in 2 isolates. erm A, tet S, tet Q and tet W genes were not detected in the isolates. Antibiotic resistance genes were found in 53.57% (15/28) sequenced isolates, 2 -3 antibiotic resistance genes were detected in 4 isolates of L. delbrueckii ssp. bulgaricus. Some LABs were not labeled in commercial yogurt products. Antibiotic resistance genes tend to be found in the starter culture of L. delbrueckii ssp. Bulgaricus and S. thermophilus. All the LAB isolates were sensitive to erythromycin and tetracycline, even though some carried erythromycin and/or tetracycline resistance genes. We proved again that LAB could carry antibiotic

  13. Carriage of antibiotic-resistant enteric bacteria varies among sites in Galapagos reptiles.

    Science.gov (United States)

    Wheeler, Emily; Hong, Pei-Ying; Bedon, Lenin Cruz; Mackie, Roderick I

    2012-01-01

    Increased overlap between humans and wildlife populations has increased the risk for novel disease emergence. Detecting contacts with a high risk for transmission of pathogens requires the identification of dependable measures of microbial exchange. We evaluated antibiotic resistance as a molecular marker for the intensity of human-wildlife microbial connectivity in the Galápagos Islands. We isolated Escherichia coli and Salmonella enterica from the feces of land iguanas (Conolophus sp.), marine iguanas (Amblyrhynchus cristatus), giant tortoises (Geochelone nigra), and seawater, and tested these bacteria with the use of the disk diffusion method for resistance to 10 antibiotics. Antibiotic-resistant bacteria were found in reptile feces from two tourism sites (Isla Plaza Sur and La Galapaguera on Isla San Cristóbal) and from seawater close to a public use beach near Puerto Baquerizo Moreno on Isla San Cristóbal. No resistance was detected at two protected beaches on more isolated islands (El Miedo on Isla Santa Fe and Cape Douglas on Isla Fernandina) and at a coastal tourism site (La Lobería on Isla San Cristóbal). Eighteen E. coli isolates from three locations, all sites relatively proximate to a port town, were resistant to ampicillin, doxycycline, tetracycline, and trimethoprin/sulfamethoxazole. In contrast, only five S. enterica isolates showed a mild decrease in susceptibility to doxycycline and tetracycline from these same sites (i.e., an intermediate resistance phenotype), but no clinical resistance was detected in this bacterial species. These findings suggest that reptiles living in closer proximity to humans potentially have higher exposure to bacteria of human origin; however, it is not clear from this study to what extent this potential exposure translates to ongoing exchange of bacterial strains or genetic traits. Resistance patterns and bacterial exchange in this system warrant further investigation to understand better how human associations

  14. Prevalence of antibiotic resistant coliform bacteria, Enterococcus spp. and Staphylococcus spp. in wastewater sewerage biofilm.

    Science.gov (United States)

    Lépesová, Kristína; Kraková, Lucia; Pangallo, Domenico; Medveďová, Alžbeta; Olejníková, Petra; Mackuľak, Tomáš; Tichý, Jozef; Grabic, Roman; Birošová, Lucia

    2018-03-28

    Urban wastewater contains different micropollutants and high number of different microorganisms. Some bacteria in wastewater can attach to the surfaces and form biofilm, which gives bacteria advantage in fight against environmental stress. This work is focused on bacterial community analysis in biofilms isolated from influent and effluent sewerage of wastewater treatment plant in Bratislava. Biofilm microbiota detection was performed by culture-independent and culture-dependent approaches. Composition of bacterial strains was detected by denaturing gradient gel electrophoresis fingerprinting coupled with the construction of 16S rRNA clone libraries. The biofilm collected at the inlet point was characterized primarily by the presence of Pseudomonas sp., Acinetobacter sp. and Janthinobacterium sp. clones, while in the biofilm isolated at outflow of wastewater treatment plant members of Pseudomonas genus were largely detected. Beside this analysis prevalence of antibiotics and resistant coliforms, Enterococcus spp. and Staphylococcus spp. in sewerage was studied. In influent wastewater were dominant antibiotics like azithromycin, clarithromycin and ciprofloxacin. Removal efficiency of these antibiotics notably azithromycin and clarithromycin were 30% in most cases. The highest number of resistant bacteria with predominance of coliforms was detected in sample of effluent biofilm. Multidrug resistant strains in effluent biofilm showed very good ability to form biofilm. Copyright © 2018. Published by Elsevier Ltd.

  15. Concentrations of antibiotics predicted to select for resistant bacteria: Proposed limits for environmental regulation.

    Science.gov (United States)

    Bengtsson-Palme, Johan; Larsson, D G Joakim

    2016-01-01

    There are concerns that selection pressure from antibiotics in the environment may accelerate the evolution and dissemination of antibiotic-resistant pathogens. Nevertheless, there is currently no regulatory system that takes such risks into account. In part, this is due to limited knowledge of environmental concentrations that might exert selection for resistant bacteria. To experimentally determine minimal selective concentrations in complex microbial ecosystems for all antibiotics would involve considerable effort. In this work, our aim was to estimate upper boundaries for selective concentrations for all common antibiotics, based on the assumption that selective concentrations a priori need to be lower than those completely inhibiting growth. Data on Minimal Inhibitory Concentrations (MICs) were obtained for 111 antibiotics from the public EUCAST database. The 1% lowest observed MICs were identified, and to compensate for limited species coverage, predicted lowest MICs adjusted for the number of tested species were extrapolated through modeling. Predicted No Effect Concentrations (PNECs) for resistance selection were then assessed using an assessment factor of 10 to account for differences between MICs and minimal selective concentrations. The resulting PNECs ranged from 8 ng/L to 64 μg/L. Furthermore, the link between taxonomic similarity between species and lowest MIC was weak. This work provides estimated upper boundaries for selective concentrations (lowest MICs) and PNECs for resistance selection for all common antibiotics. In most cases, PNECs for selection of resistance were below available PNECs for ecotoxicological effects. The generated PNECs can guide implementation of compound-specific emission limits that take into account risks for resistance promotion. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Microbiological characterization of aquatic microbiomes targeting taxonomical marker genes and antibiotic resistance genes of opportunistic bacteria.

    Science.gov (United States)

    Alexander, Johannes; Bollmann, Anna; Seitz, Wolfram; Schwartz, Thomas

    2015-04-15

    The dissemination of medically relevant antibiotic resistance genes (ARGs) (blaVIM-1, vanA, ampC, ermB, and mecA) and opportunistic bacteria (Enterococcus faecium/faecalis, Pseudomonas aeruginosa, Enterobacteriaceae, Staphylococcus aureus, and CNS) was determined in different anthropogenically influenced aquatic habitats in a selected region of Germany. Over a period of two years, four differently sized wastewater treatment plants (WWTPs) with and without clinical influence, three surface waters, four rain overflow basins, and three groundwater sites were analyzed by quantitative Polymerase Chain Reaction (qPCR). Results were calculated in cell equivalents per 100 ng of total DNA extracted from water samples and per 100 mL sample volume, which seems to underestimate the abundance of antibiotic resistance and opportunistic bacteria. High abundances of opportunistic bacteria and ARG were quantified in clinical wastewaters and influents of the adjacent WWTP. The removal capacities of WWTP were up to 99% for some, but not all investigated bacteria. The abundances of most ARG targets were found to be increased in the bacterial population after conventional wastewater treatment. As a consequence, downstream surface water and also some groundwater compartments displayed high abundances of all four ARGs. It became obvious that the dynamics of the ARG differed from the fate of the opportunistic bacteria. This underlines the necessity of an advanced microbial characterization of anthropogenically influenced environments. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Human recreational exposure to antibiotic resistant bacteria in coastal bathing waters.

    Science.gov (United States)

    Leonard, Anne F C; Zhang, Lihong; Balfour, Andrew J; Garside, Ruth; Gaze, William H

    2015-09-01

    Infections caused by antibiotic resistant bacteria (ARB) are associated with poor health outcomes and are recognised globally as a serious health problem. Much research has been conducted on the transmission of ARB to humans. Yet the role the natural environment plays in the spread of ARB and antibiotic resistance genes is not well understood. Antibiotic resistant bacteria have been detected in natural aquatic environments, and ingestion of seawater during water sports is one route by which many people could be directly exposed. The aim was to estimate the prevalence of resistance to one clinically important class of antibiotics (third-generation cephalosporins (3GCs)) amongst Escherichia coli in coastal surface waters in England and Wales. Prevalence data was used to quantify ingestion of 3GC-resistant E. coli (3GCREC) by people participating in water sports in designated coastal bathing waters. A further aim was to use this value to derive a population-level estimate of exposure to these bacteria during recreational use of coastal waters in 2012. The prevalence of 3GC-resistance amongst E. coli isolated from coastal surface waters was estimated using culture-based methods. This was combined with the density of E. coli reported in designated coastal bathing waters along with estimations of the volumes of water ingested during various water sports reported in the literature to calculate the mean number of 3GCREC ingested during different water sports. 0.12% of E. coli isolated from surface waters were resistant to 3GCs. This value was used to estimate that in England and Wales over 6.3 million water sport sessions occurred in 2012 that resulted in the ingestion of at least one 3GCREC. Despite the low prevalence of resistance to 3GCs amongst E. coli in surface waters, there is an identifiable human exposure risk for water users, which varies with the type of water sport undertaken. The relative importance of this exposure is likely to be greater in areas where a

  18. Anaerobic ammonium-oxidizing bacteria gain antibiotic resistance during long-term acclimatization.

    Science.gov (United States)

    Zhang, Zheng-Zhe; Zhang, Qian-Qian; Guo, Qiong; Chen, Qian-Qian; Jiang, Xiao-Yan; Jin, Ren-Cun

    2015-09-01

    Three broad-spectrum antibiotics, amoxicillin (AMX), florfenicol (FF) and sulfamethazine (SMZ), that inhibit bacteria via different target sites, were selected to evaluate the acute toxicity and long-term effects on anaerobic ammonium oxidation (anammox) granules. The specific anammox activity (SAA) levels reduced by approximately half within the first 3 days in the presence of antibiotics but no nitrite accumulation was observed in continuous-flow experiments. However, the SAA levels and heme c content gradually recovered as the antibiotic concentrations increased. Extracellular polymeric substances (EPS) analysis suggested that anaerobic ammonium-oxidizing bacteria gradually developed a better survival strategy during long-term acclimatization, which reduced the antibiotic stress via increased EPS secretion that provided a protective 'cocoon.' In terms of nitrogen removal efficiency, anammox granules could resist 60 mg-AMX L(-1), 10 mg-FF L(-1) and 100 mg-SMZ L(-1). This study supported the feasibility of using anammox granules to treat antibiotic-containing wastewater. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Impact of Manure Fertilization on the Abundance of Antibiotic-Resistant Bacteria and Frequency of Detection of Antibiotic Resistance Genes in Soil and on Vegetables at Harvest

    OpenAIRE

    Marti, Romain; Scott, Andrew; Tien, Yuan-Ching; Murray, Roger; Sabourin, Lyne; Zhang, Yun; Topp, Edward

    2013-01-01

    Consumption of vegetables represents a route of direct human exposure to bacteria found in soil. The present study evaluated the complement of bacteria resistant to various antibiotics on vegetables often eaten raw (tomato, cucumber, pepper, carrot, radish, lettuce) and how this might vary with growth in soil fertilized inorganically or with dairy or swine manure. Vegetables were sown into field plots immediately following fertilization and harvested when of marketable quality. Vegetable and ...

  20. Quantitative relationship between antibiotic exposure and the acquisition and transmission of resistance in bacteria in the laboratory

    NARCIS (Netherlands)

    Händel, N.

    2015-01-01

    The worldwide emergence and spread of antibiotic resistant bacteria represent a major threat to human health care as the chance of therapy failure and costs for treatment increase. To curb the continuous rise of drug resistant bacteria worldwide, new strategies are urgently needed that counteract

  1. Concentration of facultative pathogenic bacteria and antibiotic resistance genes during sewage treatment and in receiving rivers.

    Science.gov (United States)

    Heß, Stefanie; Lüddeke, Frauke; Gallert, Claudia

    2016-10-01

    Whereas the hygienic condition of drinking and bathing water by law must be monitored by culture-based methods, for quantification of microbes and antibiotic resistance in soil or the aquatic environment, often molecular genetic assays are used. For comparison of both methods, knowledge of their correlation is necessary. Therefore the population of total bacteria, Escherichia coli, enterococci and staphylococci during sewage treatment and in receiving river water was compared by agar plating and quantitative polymerase chain reaction (qPCR) assays. In parallel, all samples were investigated for clinically relevant antibiotic resistance genes. Whereas plating and qPCR data for total bacteria correlated well in sewage after primary treatment, qPCR data of river water indicated higher cell numbers for E. coli. It is unknown if these cells are 'only' not growing under standard conditions or if they are dead. Corresponding to the amount of non-culturable cells, the 'breakpoints' for monitoring water quality should be adapted. The abundances of clinically relevant antibiotic resistance genes in river water were in the same order of magnitude or even higher than in treated sewage. For estimation of the health risk it is important to investigate which species carry respective genes and whether these genes are disseminated via gene transfer.

  2. Conjugation Inhibitors and Their Potential Use to Prevent Dissemination of Antibiotic Resistance Genes in Bacteria

    Directory of Open Access Journals (Sweden)

    Elena Cabezón

    2017-11-01

    Full Text Available Antibiotic resistance has become one of the most challenging problems in health care. Bacteria conjugation is one of the main mechanisms whereby bacteria become resistant to antibiotics. Therefore, the search for specific conjugation inhibitors (COINs is of interest in the fight against the spread of antibiotic resistances in a variety of laboratory and natural environments. Several compounds, discovered as COINs, are promising candidates in the fight against plasmid dissemination. In this review, we survey the effectiveness and toxicity of the most relevant compounds. Particular emphasis has been placed on unsaturated fatty acid derivatives, as they have been shown to be efficient in preventing plasmid invasiveness in bacterial populations. Biochemical and structural studies have provided insights concerning their potential molecular targets and inhibitory mechanisms. These findings open a new avenue in the search of new and more effective synthetic inhibitors. In this pursuit, the use of structure-based drug design methods will be of great importance for the screening of ligands and binding sites of putative targets.

  3. On the contribution of reclaimed wastewater irrigation to the potential exposure of humans to antibiotics, antibiotic resistant bacteria and antibiotic resistance genes - NEREUS COST Action ES1403 position paper

    DEFF Research Database (Denmark)

    Piña, Benjamin; Bayona, Josep M.; Christou, Anastasis

    2018-01-01

    Antibiotic resistance (AR) is becoming a worldwide threat due to the increasing occurrence of antibiotic-resistant pathogenic bacterial strains. There is a general consensus about the potential implications of the use of antibiotics in livestock on the onset of antibiotic resistant bacteria (ARB......), mainly through meat consumption. However, the ever-increasing use of reclaimed wastewater (RWW) in agriculture may also contribute significantly to the non-accounted exposure to antibiotics, ARB, and antibiotic resistance genes (ARGs). This position paper aims at evaluating the current knowledge...... concerning the occurrence of antibiotics, ARBs, and ARGs in edible parts of different common crops irrigated with RWW. We will discuss which regulations on the use of RWW may contribute to the minimization of the prevalence of these contaminants in crops, and provide recommendations on how to minimize...

  4. Chemical composition and antibacterial activity of Lavandula coronopifolia essential oil against antibiotic-resistant bacteria.

    Science.gov (United States)

    Ait Said, L; Zahlane, K; Ghalbane, I; El Messoussi, S; Romane, A; Cavaleiro, C; Salgueiro, L

    2015-01-01

    The aim of this study was to analyse the composition of the essential oil (EO) of Lavandula coronopifolia from Morocco and to evaluate its in vitro antibacterial activity against antibiotic-resistant bacteria isolated from clinical infections. The antimicrobial activity was assessed by a broth micro-well dilution method using multiresistant clinical isolates of 11 pathogenic bacteria: Klebsiella pneumoniae subsp. pneumoniae, Klebsiella ornithinolytica, Escherichia coli, Enterobacter cloacae, Enterobacter aerogenes, Providencia rettgeri, Citrobacter freundii, Hafnia alvei, Salmonella spp., Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus. The main compounds of the oil were carvacrol (48.9%), E-caryophyllene (10.8%) and caryophyllene oxide (7.7%). The oil showed activity against all tested strains with minimal inhibitory concentration (MIC) values ranging between 1% and 4%. For most of the strains, the MIC value was equivalent to the minimal bactericidal concentration value, indicating a clear bactericidal effect of L. coronopifolia EO.

  5. Sewage sludge and liquid pig manure as possible sources of antibiotic resistant bacteria.

    Science.gov (United States)

    Hölzel, Christina S; Schwaiger, Karin; Harms, Katrin; Küchenhoff, Helmut; Kunz, Anne; Meyer, Karsten; Müller, Christa; Bauer, Johann

    2010-05-01

    Within the last decades, the environmental spread of antibiotic resistant bacteria has become a topic of concern. In this study, liquid pig manure (n=305) and sewage sludge (n=111) - used as agricultural fertilizers between 2002 and 2005 - were investigated for the presence of Escherichia coli, Enterococcus faecalis and Enterococcus faecium. Bacteria were tested for their resistance against 40 chemotherapeutics including several "reserve drugs". E. coli (n=613) from pig manure were at a significantly higher degree resistant to streptomycin, doxycycline, spectinomycin, cotrimoxazole, and chloramphenicol than E. coli (n=116) from sewage sludge. Enterococci (Ent. faecalis, n=387, and Ent. faecium, n=183) from pig manure were significantly more often resistant to high levels of doxycycline, rifampicin, erythromycin, and streptomycin than Ent. faecalis (n=44) and Ent. faecium (n=125) from sewage sludge. Significant differences in enterococcal resistance were also seen for tylosin, chloramphenicol, gentamicin high level, fosfomycin, clindamicin, enrofloxacin, moxifloxacin, nitrofurantoin, and quinupristin/dalfopristin. By contrast, aminopenicillins were more effective in enterococci from pig manure, and mean MIC-values of piperacillin+tazobactam and third generation cefalosporines were significantly lower in E. coli from pig manure than in E. coli from sewage sludge. 13.4% (E. coli) to 25.3% (Ent. faecium) of pig manure isolates were high-level multiresistant to substances from more than three different classes of antimicrobial agents. In sewage sludge, high-level-multiresistance reached from 0% (Ent. faecalis) to 16% (Ent. faecium). High rates of (multi-) resistant bacteria in pig manure emphasize the need for a prudent - cautious - use of antibiotics in farm animals. Copyright 2010 Elsevier Inc. All rights reserved.

  6. Antiseptic and antibiotic resistance in Gram-negative bacteria causing urinary tract infection.

    Science.gov (United States)

    Stickler, D J; Thomas, B

    1980-01-01

    A collection of 802 isolates of Gram-negative bacteria causing urinary tract infections was made from general practice, antenatal clinics, and local hospitals. The organisms were tested for their sensitivity to chlorhexidine, cetrimide, glutaraldehyde, phenyl mercuric nitrate, a phenolic formulation, and a proprietary antiseptic containing a mixture of picloxydine, octyl phenoxy polyethoxyethanol, and benzalkonium chloride. Escherichia coli, the major species isolated, proved to be uniformly sensitive to these agents. Approximately 10% of the total number of isolates, however, exhibited a degree of resistance to the cationic agents. These resistant organisms were members of the genera Proteus, Providencia, and Pseudomonas; they were also generally resistant to five, six, or seven antibiotics. It is proposed therefore that an antiseptic policy which involves the intensive use of cationic antiseptics might lead to the selection of a flora of notoriously drug-resistant species. PMID:6769972

  7. Evaluation of antibiotic resistant bacteria in underground drinking water and transfer of their resistant character to normal flora of the body.

    Science.gov (United States)

    Alam, Mehboob; Khan, Naqab; Rehman, Khurram; Khan, Samiullah; Niazi, Zahid Rasul; Shah, Kifayatullah; Baloch, Natasha; Khan, Barkat Ali

    2018-03-01

    The untreated surface water for drinking and domestic use is an alarming situation to public health especially in prevalence of antibiotics resistant bacteria. This investigation aimed to isolate and identify the antibiotic resistance bacteria in underground water samples in district Dera Ismail Khan, Pakistan. The underground water samples were collected from four different places using hand pumps (Khyber town, riverside, Gomal University and united town). Cultured on nutrient agar media, identified by Gam staining and biochemical tests. There after antibiotic resistance assay were performed by measuring zone of inhibition of different antibiotics by disc diffusion method. Six different bacterial colonies were isolated and identified as Enterobacteriaceae, Serriata specie, Proteues, Pseudomonas, all these bacterial colonies were 33% resistant to chloramphenicol with and 100% resistant to amoxicillin. Some colonies were also considered as resistant, according to the criteria of National Committee for Clinical Records (NCCL) that less than 10mm zone of inhibition are considered as resistant. Subsequently, the chloramphenicol resistance bacteria were analyzed for their ability to transfer resistant gene to sensitive bacteria. In in-vitro method, an isolate M1b (resistant) was found capable to transfer resistance gene to M1a isolate (sensitive) in nutrient rich environment. It was concluded that antibiotics resistance bacteria found in underground water, moreover capable of transferring the antibiotic resistant character to suitable recipient i.e. normal flora of the body or to other pathogens by conjugation.

  8. Detection of emerging antibiotic resistance in bacteria isolated from subclinical mastitis in cattle in West Bengal

    Directory of Open Access Journals (Sweden)

    Arnab Das

    2017-05-01

    Full Text Available Aim: The aim of this work was to detect antibiotic resistance in Gram-negative bacteria isolated from subclinical mastitis in cattle in West Bengal. Materials and Methods: The milk samples were collected from the cattle suffering with subclinical mastitis in West Bengal. The milk samples were inoculated into the nutrient broth and incubated at 37°C. On the next day, the growth was transferred into nutrient agar and MacConkey agar. All the pure cultures obtained from nutrient agar slant were subjected to Gram-staining and standard biochemical tests. All the bacterial isolates were tested in vitro for their sensitivity to different antibiotics commonly used in veterinary practices. All Gram-negative isolates including positive control were subjected to polymerase chain reaction (PCR for detection of blaCTX-M, blaTEM, blaSHV, blaVIM, tetA, tetB, tetC, and tetM genes considered for extended-spectrum β-lactamase (ESBL, metallo-β-lactamase, and tetracycline resistance. Results: In total, 50 Gram-negative organisms (Escherichia coli, Proteus, Pseudomonas, Klebsiella, and Enterobacter were isolated from milk samples of subclinical mastitis infected cattle. Among these Gram-negative isolates, 48% (24/50 were found either ESBL producing or tetracycline resistant. Out of total 50 Gram-negative isolates, blaCTX-M was detected in 18 (36% isolates, and 6 (12% harbored blaTEM genes in PCR. None of the isolates carried blaSHV genes. Further, in this study, 5 (10% isolates harbored tet(A gene, and 8 (16% isolates carried tet(B gene. No tet(C gene was detected from the isolates. Conclusion: This study showed emerging trend of antibiotic-resistant Gram-negative bacteria associated with subclinical mastitis in cattle in West Bengal, India.

  9. Motuporamine Derivatives as Antimicrobial Agents and Antibiotic Enhancers against Resistant Gram-Negative Bacteria.

    Science.gov (United States)

    Borselli, Diane; Blanchet, Marine; Bolla, Jean-Michel; Muth, Aaron; Skruber, Kristen; Phanstiel, Otto; Brunel, Jean Michel

    2017-02-01

    Dihydromotuporamine C and its derivatives were evaluated for their in vitro antimicrobial activities and antibiotic enhancement properties against Gram-negative bacteria and clinical isolates. The mechanism of action of one of these derivatives, MOTU-N44, was investigated against Enterobacter aerogenes by using fluorescent dyes to evaluate outer-membrane depolarization and permeabilization. Its efficiency correlated with inhibition of dye transport, thus suggesting that these molecules inhibit drug transporters by de-energization of the efflux pump rather than by direct interaction of the molecule with the pump. This suggests that depowering the efflux pump provides another strategy to address antibiotic resistance. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  10. Can Clays in Livestock Feed Promote Antibiotic Resistance and Virulence in Pathogenic Bacteria?

    OpenAIRE

    Rodr?guez-Rojas, Alexandro; Rodr?guez-Beltr?n, Jer?nimo; Valverde, Jos? Ram?n; Bl?zquez, Jes?s

    2015-01-01

    The use of antibiotics in animal husbandry has long been associated with the appearance of antibiotic resistance and virulence factor determinants. Nonetheless, the number of cases of human infection involving resistant or virulent microorganisms that originate in farms is increasing. While many antibiotics have been banned as dietary supplements in some countries, other additives thought to be innocuous in terms of the development and spread of antibiotic resistance are used as growth promot...

  11. Identification of antibiotic resistant bacteria community and a GeoChip based study of resistome in urban watersheds.

    Science.gov (United States)

    Low, Adrian; Ng, Charmaine; He, Jianzhong

    2016-12-01

    Urban watersheds from point sources are potential reservoirs of antibiotic resistance genes (ARGs). However, few studies have investigated urban watersheds of non-point sources. To understand the type of ARGs and bacteria that might carry such genes, we investigated two non-point source urban watersheds with different land-use profiles. Antibiotic resistance levels of two watersheds (R1, R3) were examined using heterotrophic plate counts (HPC) as a culturing method to obtain counts of bacteria resistant to seven antibiotics belonging to different classes (erythromycin, kanamycin, lincomycin, norfloxacin, sulfanilamide, tetracycline and trimethoprim). From the HPC study, 239 antibiotic resistant bacteria were characterized for resistance to more antibiotics. Furthermore, ARGs and antimicrobial biosynthesis genes were identified using GeoChip version 5.0 to elucidate the resistomes of surface waters in watersheds R1 and R3. The HPC study showed that water samples from R1 had significantly higher counts of bacteria resistant to erythromycin, kanamycin, norfloxacin, sulfanilamide, tetracycline and trimethoprim than those from R3 (Analysis of Similarity (ANOSIM), R = 0.557, p antibiotics tested, lincomycin and trimethoprim resistant bacteria are greater in abundances. The 239 antibiotic resistant isolates represent a subset of resistant bacterial populations, including bacteria not previously known for resistance. Majority of the isolates had resistance to ampicillin, vancomycin, lincomycin and trimethoprim. GeoChip revealed similar ARGs in both watersheds, but with significantly higher intensities for tetX and β-lactamase B genes in R1 than R3. The genes with the highest average normalized intensities in R1 and R3 were tetracycline (tet) and fosfomycin (fosA) resistance genes, respectively. The higher abundance of tetX genes in R1 is congruent with the higher abundance of tetracycline resistant HPC observed in R1 samples. Strong correlations (r ≥ 0.8) of efflux

  12. Microbiological and biochemical studies on certain antibiotic-resistant bacteria isolated from certain clinical specimens

    International Nuclear Information System (INIS)

    Nada, H.M.AL.M.

    2008-01-01

    Infection is a dynamic process involving invasion of the body by pathogenic microorganisms and reactions of the tissues to microorganisms and their toxins. Pathogenic microorganisms isolated from clinical samples are of great threat to human health.The outcome of an infection depends on the virulence of the pathogen and the relative degree of resistance or susceptibility to antimicrobial chemotherapy. Antimicrobial agents interfere with specific processes that are essential for growth and division.Development of antibiotic resistance in bacteria is a problem of great concern. The high prevalence of resistant bacteria seems to be related to uncontrolled usage of antibiotics. B-lactamases are the most common cause of bacterial resistance to B-lactam antimicrobial agents, and it is one of the most important reason for increasing the resistance in pathogenic bacteria against some antibiotics especially those acting on inhibition of cell wall synthesis. One hundred and seven clinical samples and specimens were collected from public, private hospitals and National Cancer Institute (NCI) in Cairo, Egypt. Out of them 72 cases positive for microbial infection. Twelve cases were showed mixed infection. Eighty four isolates of pathogenic bacteria and yeast were collected from single and mixed culture. Susceptibilities of the isolates to 20 different antimicrobial agents were determined according to Kirby-Bauer method. Nine multi-drug resistant gram-negative bacterial strains were identified by (Micro Scan WalkAway 96 SI System). Six of them urine isolates, 2 wound (pus) isolates and one sputum isolate. The identified strains were exposed to in-vitro gamma irradiation at dose level of 24.4 Gy, which is biologically equivalent to the fractionated multiple therapeutic dose used in the protocol of cancer treatment of some patients. The antimicrobial susceptibility of the nine multi-drug resistant strains were carried out by disk diffusion method before and after irradiation

  13. Microbiological and biochemical studies on certain antibiotic-resistant bacteria isolated from certain clinical specimens

    Energy Technology Data Exchange (ETDEWEB)

    Nada, H M.AL.M. [National Center for Radiation Research and Technology, Atomic Energy Authority, Cairo (Egypt)

    2008-07-01

    Infection is a dynamic process involving invasion of the body by pathogenic microorganisms and reactions of the tissues to microorganisms and their toxins. Pathogenic microorganisms isolated from clinical samples are of great threat to human health.The outcome of an infection depends on the virulence of the pathogen and the relative degree of resistance or susceptibility to antimicrobial chemotherapy. Antimicrobial agents interfere with specific processes that are essential for growth and division.Development of antibiotic resistance in bacteria is a problem of great concern. The high prevalence of resistant bacteria seems to be related to uncontrolled usage of antibiotics. B-lactamases are the most common cause of bacterial resistance to B-lactam antimicrobial agents, and it is one of the most important reason for increasing the resistance in pathogenic bacteria against some antibiotics especially those acting on inhibition of cell wall synthesis. One hundred and seven clinical samples and specimens were collected from public, private hospitals and National Cancer Institute (NCI) in Cairo, Egypt. Out of them 72 cases positive for microbial infection. Twelve cases were showed mixed infection. Eighty four isolates of pathogenic bacteria and yeast were collected from single and mixed culture. Susceptibilities of the isolates to 20 different antimicrobial agents were determined according to Kirby-Bauer method. Nine multi-drug resistant gram-negative bacterial strains were identified by (Micro Scan WalkAway 96 SI System). Six of them urine isolates, 2 wound (pus) isolates and one sputum isolate. The identified strains were exposed to in-vitro gamma irradiation at dose level of 24.4 Gy, which is biologically equivalent to the fractionated multiple therapeutic dose used in the protocol of cancer treatment of some patients. The antimicrobial susceptibility of the nine multi-drug resistant strains were carried out by disk diffusion method before and after irradiation

  14. Microbiological air quality in some kindergartens and antibiotic resistance of bacteria of the Staphylococcus spp. genus

    Directory of Open Access Journals (Sweden)

    Łukasz Kubera

    2015-02-01

    Full Text Available Background: Microbiological contamination of the air and the acquisition of the antibiotic resistance by pathogenic bacteria is a growing phenomenon that has a substantial impact on the quality of our health. This problem applies mainly to public areas where we spend a large part of our lives. This study was focused on the microbiological analysis of the air in some kindergartens and antibiotic resistance of bacteria of the Stephylococcus spp. genus. The identification of the isolated mould fungi has been also made. Material and Methods: Air samples were collected from classrooms in the seasonal cycle in the mornings and afternoons using 2 methods, sedimentation and impact. Air samples collected outside the kindergartens served as controls. Air quality assessments were based on the groups of indicator microorganisms, according to Polish standards. The susceptibility of isolated staphylococci was assessed with the disc-diffusion method, using 8 different classes of antibiotics, in line with the recommendations of the European Committee on Antimicrobial Susceptibility Testing (EUCAST. Results: The analyses show that, regardless of the method, the total number of heterothropic bacteria and staphylococci in the air of the analyzed kindergartens exceeded the allowable limits. There was no air pollution with the fungal infection. Based on the antibiogram, it was found that Staphylococcus spp. strains showed the highest sensitivity to chloramphenicol and the lowest to penicillin and gentamicin. Among the fungi moulds of the genus Cladosporium predominated. Conclusions: The results of the analyses highlight the need for regular health checks and further research to help identify biological factors that may significantly affect the quality of health of people living in public spaces. Med Pr 2015;66(1:49–56

  15. Bacteriophage and lytic enzymes - can they help us in the war with antibiotic resistant bacteria

    International Nuclear Information System (INIS)

    Trudil, D.; Rainina, E.

    2009-01-01

    Drug-resistant pathogens are a growing menace to all people, regardless of age, or socioeconomic background. They endanger people industrial societies like the United States, as well as in less developed nations and are even causing problems in military field hospitals. From Streptococcus pneumoniae to Staphylococcus, C. difficile, and multidrug-resistant TB, the list is growing. The threat of engineered microorganisms further complicates the interaction between man and Mother Nature. Additionally, although antibiotics were specifically designed for treating human health emergencies, their use for raising livestock animals has expanded. In the US, large amounts of antibiotics are routinely mixed into feed in order to promote growth rather than combat disease and as prophylactic treatment to offset unnatural diets and unhealthy living conditions. U.S.-raised animals in the 1950s received 2 million pounds per year of antibiotics in their feed compared to 50 million pounds today-a 2,500-percent increase. A large percentage of these drugs pass into the environment. In fact, prior to 1995, when fluoroquinolones were first approved to treat poultry, very few fluoroquinolone-resistant Campylobacter were found in people with foodborne diseases in the United States. After the approval, however, many more fluoroquinolone-resistant bacteria were found in humans and in poultry from slaughter plants and retail stores. The threat to our food supply becomes a threat to security. What can be done? One approach is to treat bacterial diseases by the use of bacteriophages. Phages are very small viruses that destroy by lysing select bacteria. The idea of using phage as a therapy for infectious bacterial diseases was first proposed by d'Herelle around World War I and over 80 years bacteriophage has been a key tool of healthcare professionals within Eastern Europe. More recently professionals in the USA and Western Europe have isolated and developed specific lytic components which have

  16. Antibiotic resistance of lactic acid bacteria and Bifidobacterium spp. isolated from dairy and pharmaceutical products.

    Science.gov (United States)

    D'Aimmo, Maria Rosaria; Modesto, Monica; Biavati, Bruno

    2007-04-01

    The outlines of antibiotic resistance of some probiotic microorganisms were studied. This study was conducted with the double purpose of verifying their ability to survive if they are taken simultaneously with an antibiotic therapy and to increase the selective properties of suitable media for the isolation of samples containing mixed bacterial populations. We isolated from commercial dairy and pharmaceutical products, 34 strains declared as probiotics, belonging to the genera Bifidobacterium and Lactobacillus, and 21 strains of starter culture bacteria. All the microorganisms have been compared by electrophoresis of the soluble proteins for the purpose of identifying them. A Multiplex-PCR with genus- and species-specific primers was used to detect for Bifidobacterium animalis subsp. lactis presence. All bifidobacteria were B. animalis subsp. lactis except one Bifidobacterium longum. Sometimes the identification showed that the used strain was not the one indicated on the label. The lactobacilli were Lactobacillus acidophilus, Lactobacillus casei, and Lactobacillus delbrueckii subsp. bulgaricus. The streptococci were all Streptococcus thermophilus. The minimal inhibitory concentration (MIC) of 24 common antibiotic substances has been valued by the broth microdilution method. All tested strains were susceptible to ampicillin, bacitracin, clindamycin, dicloxacillin, erytromycin, novobiocin, penicillin G, rifampicin (MIC(90) ranging from 0.01 to 4 microg/ml); resistant to aztreonam, cycloserin, kanamycin, nalidixic acid, polymyxin B and spectinomycin (MIC(90) ranging from 64 to >1000 microg/ml). The susceptibility to cephalothin, chloramphenicol, gentamicin, lincomycin, metronidazole, neomycin, paromomycin, streptomycin, tetracycline and vancomycin was variable and depending on the species.

  17. Low antibiotic resistance among anaerobic Gram-negative bacteria in periodontitis 5 years following metronidazole therapy.

    Science.gov (United States)

    Dahlen, G; Preus, H R

    2017-02-01

    The objective of this study was to assess antibiotic susceptibility among predominant Gram-negative anaerobic bacteria isolated from periodontitis patients who 5 years prior had been subject to mechanical therapy with or without adjunctive metronidazole. One pooled sample was taken from the 5 deepest sites of each of 161 patients that completed the 5 year follow-up after therapy. The samples were analyzed by culture. A total number of 85 anaerobic strains were isolated from the predominant subgingival flora of 65/161 patient samples, identified, and tested for antibiotic susceptibility by MIC determination. E-tests against metronidazole, penicillin, amoxicillin, amoxicillin + clavulanic acid and clindamycin were employed. The 73/85 strains were Gram-negative rods (21 Porphyromonas spp., 22 Prevotella/Bacteroides spp., 23 Fusobacterium/Filifactor spp., 3 Campylobacter spp. and 4 Tannerella forsythia). These were all isolated from the treated patients irrespective of therapy procedures (+/-metronidazole) 5 years prior. Three strains (Bifidobacterium spp., Propionibacterium propionicum, Parvimonas micra) showed MIC values for metronidazole over the European Committee on Antimicrobial Susceptibility Testing break point of >4 μg/mL. All Porphyromonas and Tannerella strains were highly susceptible. Metronidazole resistant Gram-negative strains were not found, while a few showed resistance against beta-lactam antibiotics. In this population of 161 patients who had been subject to mechanical periodontal therapy with or without adjunct metronidazole 5 years prior, no cultivable antibiotic resistant anaerobes were found in the predominant subgingival microbiota. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Synergistic Antibacterial Effects of Chitosan-Caffeic Acid Conjugate against Antibiotic-Resistant Acne-Related Bacteria.

    Science.gov (United States)

    Kim, Ji-Hoon; Yu, Daeung; Eom, Sung-Hwan; Kim, Song-Hee; Oh, Junghwan; Jung, Won-Kyo; Kim, Young-Mog

    2017-06-08

    The object of this study was to discover an alternative therapeutic agent with fewer side effects against acne vulgaris, one of the most common skin diseases. Acne vulgaris is often associated with acne-related bacteria such as Propionibacterium acnes , Staphylococcus epidermidis , Staphylococcus aureus , and Pseudomonas aeruginosa . Some of these bacteria exhibit a resistance against commercial antibiotics that have been used in the treatment of acne vulgaris (tetracycline, erythromycin, and lincomycin). In the current study, we tested in vitro antibacterial effect of chitosan-phytochemical conjugates on acne-related bacteria. Three chitosan-phytochemical conjugates used in this study exhibited stronger antibacterial activity than that of chitosan (unmodified control). Chitosan-caffeic acid conjugate (CCA) showed the highest antibacterial effect on acne-related bacteria along with minimum inhibitory concentration (MIC; 8 to 256 μg/mL). Additionally, the MIC values of antibiotics against antibiotic-resistant P. acnes and P. aeruginosa strains were dramatically reduced in combination with CCA, suggesting that CCA would restore the antibacterial activity of the antibiotics. The analysis of fractional inhibitory concentration (FIC) indices clearly revealed a synergistic antibacterial effect of CCA with antibiotics. Thus, the median sum of FIC (∑FIC) values against the antibiotic-resistant bacterial strains ranged from 0.375 to 0.533 in the combination mode of CCA and antibiotics. The results of the present study suggested a potential possibility of chitosan-phytochemical conjugates in the control of infections related to acne vulgaris.

  19. Antibiotic resistance reservoirs

    NARCIS (Netherlands)

    Versluis, Dennis

    2016-01-01

    One of the major threats to human health in the 21st century is the emergence of pathogenic bacteria that are resistant to multiple antibiotics, thereby limiting treatment options. An important route through which pathogens become resistant is via acquisition of resistance genes from

  20. Antibiotic resistance patterns of bacteria isolated from indwelling Foley catheters following tube cystostomy in goats with obstructive urolithiasis.

    Science.gov (United States)

    Chigerwe, Munashe; Mavangira, Vengai; Byrne, Barbara A; Angelos, John A

    2017-05-01

    Tube cystostomy is a surgical method used for managing obstructive urolithiasis and involves placement of a Foley catheter into the urinary bladder. We identified and evaluated the antibiotic resistance patterns of bacteria isolated from indwelling Foley catheters following tube cystostomy in goats with obstructive urolithiasis. Urine samples collected over a 10-y period from catheter tips at the time of removal were submitted for bacteriologic culture and antibiotic susceptibility testing. Resistance patterns to antibiotics, trends in the resistance patterns over the study period, and the probability of a bacterial isolate being resistant as a function of the identity of the isolate and antibiotic tested were determined. A total of 103 urine samples from 103 male goats with obstructive urolithiasis managed surgically with tube cystostomy were included in the study. Aerococcus (36.9%) and Enterococcus (30.1%) were isolated most frequently. The susceptibility patterns of all bacteria isolated did not change over the study period ( p > 0.05). Proportions of isolates resistant to 1, 2, and ≥3 antibiotics were 36.9%, 18.5%, and 23.3%, respectively. Thus, 41.8% of bacterial isolates were resistant to 2 or more antibiotics tested. The probability of Aerococcus spp., Escherichia coli, and Pseudomonas aeruginosa isolates to be resistant to ampicillin, ceftiofur, erythromycin, penicillin, or tetracycline ranged from 0.59 to 0.76.

  1. Antibiotic resistant bacteria in urban sewage: Role of full-scale wastewater treatment plants on environmental spreading.

    Science.gov (United States)

    Turolla, A; Cattaneo, M; Marazzi, F; Mezzanotte, V; Antonelli, M

    2018-01-01

    The presence of antibiotic resistant bacteria (ARB) in wastewater was investigated and the role of wastewater treatment plants (WWTPs) in promoting or limiting antibiotic resistance was assessed. Escherichia coli (E. coli) and total heterotrophic bacteria (THB) resistance to ampicillin, chloramphenicol and tetracycline was monitored in three WWTPs located in Milan urban area (Italy), differing among them for the operating parameters of biological process, for the disinfection processes (based on sodium hypochlorite, UV radiation, peracetic acid) and for the discharge limits to be met. Wastewater was collected from three sampling points along the treatment sequence (WWTP influent, effluent from sand filtration, WWTP effluent). Antibiotic resistance to ampicillin was observed both for E. coli and for THB. Ampicillin resistant bacteria in the WWTP influents were 20-47% of E. coli and 16-25% of THB counts. A limited resistance to chloramphenicol was observed only for E. coli, while neither for E. coli nor for THB tetracycline resistance was observed. The biological treatment and sand filtration led to a decrease in the maximum percentage of ampicillin-resistant bacteria (20-29% for E. coli, 11-21% for THB). However, the conventionally adopted parameters did not seem adequate to support an interpretation of WWTP role in ARB spread. Peracetic acid was effective in selectively acting on antibiotic resistant THB, unlike UV radiation and sodium hypochlorite. The low counts of E. coli in WWTP final effluents in case of agricultural reuse did not allow to compare the effect of the different disinfection processes on antibiotic resistance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Effect of antibiotic stewardship on the incidence of infection and colonisation with antibiotic-resistant bacteria and Clostridium difficile infection: a systematic review and meta-analysis.

    Science.gov (United States)

    Baur, David; Gladstone, Beryl Primrose; Burkert, Francesco; Carrara, Elena; Foschi, Federico; Döbele, Stefanie; Tacconelli, Evelina

    2017-09-01

    Antibiotic stewardship programmes have been shown to reduce antibiotic use and hospital costs. We aimed to evaluate evidence of the effect of antibiotic stewardship on the incidence of infections and colonisation with antibiotic-resistant bacteria. For this systematic review and meta-analysis, we searched PubMed, the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, and Web of Science for studies published from Jan 1, 1960, to May 31, 2016, that analysed the effect of antibiotic stewardship programmes on the incidence of infection and colonisation with antibiotic-resistant bacteria and Clostridium difficile infections in hospital inpatients. Two authors independently assessed the eligibility of trials and extracted data. Studies involving long-term care facilities were excluded. The main outcomes were incidence ratios (IRs) of target infections and colonisation per 1000 patient-days before and after implementation of antibiotic stewardship. Meta-analyses were done with random-effect models and heterogeneity was calculated with the I 2 method. We included 32 studies in the meta-analysis, comprising 9 056 241 patient-days and 159 estimates of IRs. Antibiotic stewardship programmes reduced the incidence of infections and colonisation with multidrug-resistant Gram-negative bacteria (51% reduction; IR 0·49, 95% CI 0·35-0·68; pdifficile infections (32%; 0·68, 0·53-0·88; p=0·0029). Antibiotic stewardship programmes were more effective when implemented with infection control measures (IR 0·69, 0·54-0·88; p=0·0030), especially hand-hygiene interventions (0·34, 0·21-0·54; pinfections and colonisation with antibiotic-resistant bacteria and C difficile infections in hospital inpatients. These results provide stakeholders and policy makers with evidence for implementation of antibiotic stewardship interventions to reduce the burden of infections from antibiotic-resistant bacteria. German Center for Infection Research

  3. Multiple antibiotic resistance patterns of rhizospheric bacteria isolated from Phragmites australis growing in constructed wetland for distillery effluent treatment.

    Science.gov (United States)

    Chaturvedi, Sonal; Chandra, Ram; Rai, Vibhuti

    2008-01-01

    Susceptibility patterns of 12 different antibiotics were investigated against rhizospheric bacteria isolated from Phragmites australis from three different zones i.e. upper (0-5 cm), middle (5-10 cm), lower (10-15 cm) in constructed wetland system with and without distillery effluent. The major pollutants of distillery effluent were phenols, sulphide, heavy metals, and higher levels of biological oxygen demand (BOD), chemical oxygen demand (COD) etc. The antibiotic resistance properties of bacteria were correlated with the heavy metal tolerance (one of distillery pollutant). Twenty-two species from contaminated and seventeen species from non-contaminated site were tested by agar disc-diffusion method. The results revealed that more than 63% of total isolates were resistance towards one or more antibiotics tested from all the three different zones of contaminated sites. The multiple-drug resistance property was shown by total 8 isolates from effluent contaminated region out of which 3 isolates were from upper zone, 3 isolates from middle zone and 2 isolates were from lower zone. Results indicated that isolates from contaminated rhizosphere were found more resistant to antibiotics than isolates from non-contaminated rhizosphere. Further this study produces evidence suggesting that tolerance to antibiotics was acquired by isolates for the adaptation and detoxification of all the pollutants present in the effluent at contaminated site. This consequently facilitated the phytoremediation of effluent, which emerges the tolerance and increases resistance to antibiotics.

  4. Phenotypic Resistance to Antibiotics

    Directory of Open Access Journals (Sweden)

    Jose L. Martinez

    2013-04-01

    Full Text Available The development of antibiotic resistance is usually associated with genetic changes, either to the acquisition of resistance genes, or to mutations in elements relevant for the activity of the antibiotic. However, in some situations resistance can be achieved without any genetic alteration; this is called phenotypic resistance. Non-inherited resistance is associated to specific processes such as growth in biofilms, a stationary growth phase or persistence. These situations might occur during infection but they are not usually considered in classical susceptibility tests at the clinical microbiology laboratories. Recent work has also shown that the susceptibility to antibiotics is highly dependent on the bacterial metabolism and that global metabolic regulators can modulate this phenotype. This modulation includes situations in which bacteria can be more resistant or more susceptible to antibiotics. Understanding these processes will thus help in establishing novel therapeutic approaches based on the actual susceptibility shown by bacteria during infection, which might differ from that determined in the laboratory. In this review, we discuss different examples of phenotypic resistance and the mechanisms that regulate the crosstalk between bacterial metabolism and the susceptibility to antibiotics. Finally, information on strategies currently under development for diminishing the phenotypic resistance to antibiotics of bacterial pathogens is presented.

  5. [BACTERIA WITHOUT BORDERS: A HIGH CARRIAGE RATE OF ANTIBIOTIC-RESISTANT BACTERIA AMONG SYRIAN CHILDREN HOSPITALIZED IN GALILEE MEDICAL CENTER].

    Science.gov (United States)

    Faour Kassem, Diana; Shahar, Naama; Ocampo, Smadar; Bader, Tarif; Zonis, Zeev; Glikman, Daniel

    2017-05-01

    As the civil war in Syria enters its fifth year, the Israeli government continues to provide humanitarian aid to Syrian civilians in Israeli hospitals. Many wounded Syrian children are treated at the Galilee Medical Center (GMC). Due to the patients' incomplete medical history and increasing infection rates in Syria, contact isolation and screening cultures for multi-drug resistant bacteria (MDR's) are conducted upon admission for all Syrian children. To describe the rate of MDR carriage in Syrian children and compare it to hospitalized Israeli children. Prospective collection of screening culture data of Syrian patients admitted to GMC between 6/2013-11/2014 and comparison with Israeli children admitted between 1-3/2014. Extended-spectrum beta- lactamase-producing Enterobateriaceae (ESBL), Vancomycin-resistant Enterococcus (VRE), Carbapenem-resistant Enterobacteriaceae (CRE), and Methicillin-resistant Staphylococcus aureus (MRSA) were considered MDR's. Of 47 pediatric Syrian patients, 41 were severely wounded. MDR's were found in 37 (79%) children; most of the isolates were ESBL+ Escherichia coli. Over half of the ESBL's were resistant to additional antibiotics such as sulfa and quinolones; no resistance to amikacin was found. In comparison, in 6 of 40 (15%) Israeli children, MDR's (all ESBL's) were found (p<0.001). In hospitalized Syrian children, contact isolation and screening cultures for MDR's have an important role in the prevention of nosocomial transmission and establishment of empiric antimicrobial protocols. In suspected infections in Syrian children, amikacin and carbapenems are the antimicrobials of choice. MDR's are carried to a lesser extent in Israeli children but due to their importance, further largescale research is needed.

  6. Removal of total and antibiotic resistant bacteria in advanced wastewater treatment by ozonation in combination with different filtering techniques.

    Science.gov (United States)

    Lüddeke, Frauke; Heß, Stefanie; Gallert, Claudia; Winter, Josef; Güde, Hans; Löffler, Herbert

    2015-02-01

    Elimination of bacteria by ozonation in combination with charcoal or slow sand filtration for advanced sewage treatment to improve the quality of treated sewage and to reduce the potential risk for human health of receiving surface waters was investigated in pilot scale at the sewage treatment plant Eriskirch, Baden-Wuerttemberg/Germany. To determine the elimination of sewage bacteria, inflowing and leaving wastewater of different treatment processes was analysed in a culture-based approach for its content of Escherichia coli, enterococci and staphylococci and their resistance against selected antibiotics over a period of 17 month. For enterococci, single species and their antibiotic resistances were identified. In comparison to the established flocculation filtration at Eriskirch, ozonation plus charcoal or sand filtration (pilot-scale) reduced the concentrations of total and antibiotic resistant E. coli, enterococci and staphylococci. However, antibiotic resistant E. coli and staphylococci apparently survived ozone treatment better than antibiotic sensitive strains. Neither vancomycin resistant enterococci nor methicillin resistant Staphylococcus aureus (MRSA) were detected. The decreased percentage of antibiotic resistant enterococci after ozonation may be explained by a different ozone sensitivity of species: Enterococcus faecium and Enterococcus faecalis, which determined the resistance-level, seemed to be more sensitive for ozone than other Enterococcus-species. Overall, ozonation followed by charcoal or sand filtration led to 0.8-1.1 log-units less total and antibiotic resistant E. coli, enterococci and staphylococci, as compared to the respective concentrations in treated sewage by only flocculation filtration. Thus, advanced wastewater treatment by ozonation plus charcoal or sand filtration after common sewage treatment is an effective tool for further elimination of microorganisms from sewage before discharge in surface waters. Copyright © 2014 Elsevier

  7. Presence and potential for horizontal transfer of antibiotic resistance in oxidase-positive bacteria populating raw salad vegetables.

    Science.gov (United States)

    Bezanson, G S; MacInnis, R; Potter, G; Hughes, T

    2008-09-30

    To assess whether domestically grown fresh salad vegetables constitute a possible reservoir of antibiotic resistance for Canadian consumers, aerobic bacteria capable of forming colonies at 30 degrees C on nutrient-limited media were recovered from a single sampling of Romaine lettuce, Savoy spinach and alfalfa sprouts, then examined for their susceptibility to ten antibiotics and the carriage of potentially mobile R-plasmids and integrons. Of the 140 isolates resistant to one or more antibiotic, 93.5 and 90.0% were resistant to ampicillin and cephalothin; 35.7% to chloramphenicol, 10.0% to streptomycin, 4.2% to nalidixic acid, 4.2% to kanamycin, and 2.8% to gentamicin. Gram-positive isolates accounted for less than 4% of the antibiotic resistant strains. A small portion (23.1%) of the predominant oxidase-positive, gram-negative isolates was resistant to two or more antimicrobials. Members of the Pseudomonas fluorescens/putida complex were most prevalent among the 34 resistant strains identified. Sphingobacterium spp. and Acinetobacter baumanni also were detected. Ten of 52 resistant strains carried plasmids, 3 of which were self-transmissible and bore resistance to ampicillin and kanamycin. Eighteen of 48 gave PCR evidence for integron DNA. Class 2 type integrons were the most prevalent, followed by class 1. We conclude that the foods examined here carry antibiotic resistant bacteria at the retail level. Further, our determination that resistant strains contain integron-specific DNA sequences and self-transmissible R-plasmids indicates their potential to influence the pool of antibiotic resistance in humans via lateral gene transfer subsequent to ingestion.

  8. Multicentre investigation of pathogenic bacteria and antibiotic resistance genes in Chinese patients with acute exacerbation of chronic obstructive pulmonary disease.

    Science.gov (United States)

    Ma, Xiuqing; Cui, Junchang; Wang, Jing; Chang, Yan; Fang, Qiuhong; Bai, Changqing; Zhou, Xiumei; Zhou, Hong; Feng, Huasong; Wang, Ying; Zhao, Weiguo; Wen, Zhongguang; Wang, Ping; Liu, Yi; Yu, Ling; Li, Chunsun; Chen, Liangan

    2015-10-01

    A prospective observational study to investigate the distribution and antimicrobial resistance of pathogenic bacteria in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) in Beijing, China. Patients with AECOPD were recruited from 11 general hospitals. Sputum specimens were cultured and bacteria identified. Antibiotic susceptibility was determined for each isolate, and presence of antibiotic resistance genes was evaluated using polymerase chain reaction. Pathogenic bacteria were isolated from 109/318 patients (34.28%); 124 isolates of 22 pathogenic bacterial species were identified, including Klebsiella pneumoniae (16.94%), Pseudomonas aeruginosa (16.94%), Acinetobacter baumannii (11.29%), Streptococcus pneumoniae (8.87%), and Staphylococcus aureus (7.26%). S. aureus was sensitive to tigecycline, teicoplanin, vancomycin and linezolid but resistant to penicillin and levofloxacin. K.pneumoniae, P. aeruginosa, A. baumannii and E. coli were susceptible to amikacin and cefoperazone. K. pneumoniae and P. aeruginosa are the most common pathogenic bacteria in AECOPD cases in Beijing, China. Our antibiotic resistance findings may be helpful in selecting antibiotic therapy. © The Author(s) 2015.

  9. Bacterial cheating limits antibiotic resistance

    Science.gov (United States)

    Xiao Chao, Hui; Yurtsev, Eugene; Datta, Manoshi; Artemova, Tanya; Gore, Jeff

    2012-02-01

    The widespread use of antibiotics has led to the evolution of resistance in bacteria. Bacteria can gain resistance to the antibiotic ampicillin by acquiring a plasmid carrying the gene beta-lactamase, which inactivates the antibiotic. This inactivation may represent a cooperative behavior, as the entire bacterial population benefits from removing the antibiotic. The cooperative nature of this growth suggests that a cheater strain---which does not contribute to breaking down the antibiotic---may be able to take advantage of cells cooperatively inactivating the antibiotic. Here we find experimentally that a ``sensitive'' bacterial strain lacking the plasmid conferring resistance can invade a population of resistant bacteria, even in antibiotic concentrations that should kill the sensitive strain. We observe stable coexistence between the two strains and find that a simple model successfully explains the behavior as a function of antibiotic concentration and cell density. We anticipate that our results will provide insight into the evolutionary origin of phenotypic diversity and cooperative behaviors.

  10. Antibiotics and heavy metals resistance patterns of Enterococcus faecalis and faecium bacteria isolated from the human and the livestock sources

    Directory of Open Access Journals (Sweden)

    Yaser Sharifi

    2015-12-01

    Full Text Available Background: Enterococci have emerged as a major cause of nosocomial infections and within this group, Enterococcus faecalis and Enterococcus faecium cause the majority of human and livestock enterococcal infections. In this article, we tried to determine antibiotics and metals resistance patterns of E. faecalis and E. faecium strains. Methods: One hundred sixty different strains of E. faecalis and E. faecium were collected from livestock sewage and the human fecal waste during 15 months. Then bacterial antibiotics sensitivity tests were carried out using the Agar disc diffusion method. Results: Generally, 100% of E. faecalis strains separated from human and livestock sources (i.e. sheep showed penicillin (P/ kanamycin (K/ nitrofurantoin (N/ loracarbef (L/ Ciprofloxacin (Cc/ ampicillin (AN/ nalidixic acid (NA/ sulfamethoxazole (S antibiotics resistance patterns. In addition, 55% of isolated E. faecium showed P/S/AN/NA antibiotics resistance patterns. Each strain showed a resistance to at least two aminoglycoside antibiotics. However, E. faecalis strains from human and the livestock sources showed 94% and 100% of resistance to nitrofurantoin, respectively. The effects of different metal concentrations was evaluated in both strains. The agar dilution method was applied in this stage. Hg at 0.05 mmol/L of minimum inhibitory concentration (MIC showed toxicity to both the human and livestock Enterococcus strains. Cadmium at 1 mmol/L and 0.5 mmol/L concentrations had the most toxicity to E. faecalis and E. faecium strains, respectively. Obviously, toxicity to bacteria is less than other metals. As a result, Zn/Ni/Cu/Co resistance pattern is suggested for both strains. Finally, antibiotics and heavy metals resistance patterns were monitored simultaneously. Conclusion: Almost all E. faecalis strains isolated from humans and livestock showed antibiotics and heavy metals resistance patterns of P/K/L/Cc/S/AN/NA/Zn/Cu/Co simultaneously. Moreover, 55% of E

  11. Antibiotic resistance and biofilm formation of some bacteria isolated from sediment, water and fish farms in Malaysia

    Science.gov (United States)

    Faja, Orooba Meteab; Usup, Gires; Ahmad, Asmat

    2018-04-01

    A total of 90 isolates of bacteria were isolated, from sediment (10) samples, water (10) samples and fish (12) samples (Sea bass, Snapper, Grouper and Tilapia). These include 22 isolates of bacteria from sediment, 28 isolates from water and 40 isolates from fish. All the isolates were tested for sensitivity to 13 antibiotics using disc diffusion method. The isolates showed high resistance to some antibiotics based on samples source. Isolates from sediment showed highest resistance toward novobiocin, kanamycin, ampicillin and streptomycin while isolates from water showed highest resistance against vancomycin, penicillin, streptomycin and tetracycline, in contrast, in fish sample showed highest resistance toward vancomycin, ampicillin, streptomycin and tetracycline. Most of the isolates showed biofilm formation ability with different degrees. Out of 22 bacteria isolates from water, two isolates were weak biofilm formers, six isolates moderate biofilm formers and fourteen isolates strong biofilm formers. While, out of 28 bacteria isolates from water one isolate was weak biofilm former, five isolates moderate biofilm formers and 22 strong biofilm formers Fish isolate showed three isolates (8%) moderate biofilm formers and 27 isolates strong biofilm formers. Biofilm formation was one of the factors that lead to antibiotic resistance of the bacterial isolates from these samples.

  12. The Survey of Withani somnifera Extraction against Resistant Strains of Pseudomonas aeruginosa Bacteria to Selective Antibiotics

    Directory of Open Access Journals (Sweden)

    Mohammad Bokaeian

    2015-11-01

    Full Text Available Introduction:  Due  to  more  resistance  of  pathogenic  bacteria  to  new  and  current antibiotics  researchers  are  looking  to  find  the  agents  of  herbal  with  antimicrobial activities in order to replace chemical drugs.Methods:   The herbal extract of Withani somnifera was done by using a rotary vacuum,20 strains of Pseudomons aeruginosa were isolated from urinary infections hospitalized patients  in  city of Zabol  hospital.  The  MIC  Withani  somnifera  were  determined  by dilution method in various concentrations. Sensitivity of strains to multiple antibiotics was evaluated by standard disk diffusion Kirby-Bauer.Results:    The  result  showed  that  P.  aeruginosa  were  resistance  to  4  of the  agents including ampicillin  (85%, nitrofurantoin  (65%, nalidixic acid  (65%, ciprofloxacin (15% and for 5 strains of Pseudomonas showed MIC with activity of 100 ppm.Conclusion:   This  study  has  suggested  the  effect  of  winter  cherry  extract  on  P. aeruginosa in the in vitro assay. It s effectiveness of on in vivo system can be examined in future.

  13. Systematic Review: Impact of point sources on antibiotic-resistant bacteria in the natural environment.

    Science.gov (United States)

    Bueno, I; Williams-Nguyen, J; Hwang, H; Sargeant, J M; Nault, A J; Singer, R S

    2018-02-01

    Point sources such as wastewater treatment plants and agricultural facilities may have a role in the dissemination of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARG). To analyse the evidence for increases in ARB in the natural environment associated with these point sources of ARB and ARG, we conducted a systematic review. We evaluated 5,247 records retrieved through database searches, including both studies that ascertained ARG and ARB outcomes. All studies were subjected to a screening process to assess relevance to the question and methodology to address our review question. A risk of bias assessment was conducted upon the final pool of studies included in the review. This article summarizes the evidence only for those studies with ARB outcomes (n = 47). Thirty-five studies were at high (n = 11) or at unclear (n = 24) risk of bias in the estimation of source effects due to lack of information and/or failure to control for confounders. Statistical analysis was used in ten studies, of which one assessed the effect of multiple sources using modelling approaches; none reported effect measures. Most studies reported higher ARB prevalence or concentration downstream/near the source. However, this evidence was primarily descriptive and it could not be concluded that there is a clear impact of point sources on increases in ARB in the environment. To quantify increases in ARB in the environment due to specific point sources, there is a need for studies that stress study design, control of biases and analytical tools to provide effect measure estimates. © 2017 Blackwell Verlag GmbH.

  14. Can Clays in Livestock Feed Promote Antibiotic Resistance and Virulence in Pathogenic Bacteria?

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    Alexandro Rodríguez-Rojas

    2015-07-01

    Full Text Available The use of antibiotics in animal husbandry has long been associated with the appearance of antibiotic resistance and virulence factor determinants. Nonetheless, the number of cases of human infection involving resistant or virulent microorganisms that originate in farms is increasing. While many antibiotics have been banned as dietary supplements in some countries, other additives thought to be innocuous in terms of the development and spread of antibiotic resistance are used as growth promoters. In fact, several clay materials are routinely added to animal feed with the aim of improving growth and animal product quality. However, recent findings suggest that sepiolite, a clay additive, mediates the direct transfer of plasmids between different bacterial species. We therefore hypothesize that clays present in animal feed facilitate the horizontal transfer of resistance determinants in the digestive tract of farm animals.

  15. Antibiotic-resistant bacteria: prevalence in food and inactivation by food-compatible compounds and plant extracts.

    Science.gov (United States)

    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.

  16. Antibiotics from predatory bacteria

    Directory of Open Access Journals (Sweden)

    Juliane Korp

    2016-03-01

    Full Text Available Bacteria, which prey on other microorganisms, are commonly found in the environment. While some of these organisms act as solitary hunters, others band together in large consortia before they attack their prey. Anecdotal reports suggest that bacteria practicing such a wolfpack strategy utilize antibiotics as predatory weapons. Consistent with this hypothesis, genome sequencing revealed that these micropredators possess impressive capacities for natural product biosynthesis. Here, we will present the results from recent chemical investigations of this bacterial group, compare the biosynthetic potential with that of non-predatory bacteria and discuss the link between predation and secondary metabolism.

  17. Controlling antibiotic resistance in the ICU

    NARCIS (Netherlands)

    Derde, L.P.G.

    2013-01-01

    Patients admitted to intensive care units (ICUs) are frequently colonized with (antibiotic-resistant) bacteria, which may lead to healthcare associated infections. Antimicrobial-resistant bacteria (AMRB), such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococci

  18. The frequency of resistance to antibiotics of most frequently isolated bacteria from blood cultures during the period 1997-2002

    Directory of Open Access Journals (Sweden)

    Mirović Veljko

    2004-01-01

    Full Text Available The aim of this study was to determine the frequency of resistance to antibiotics of the most frequently isolated bacteria from blood cultures of hospitalized patients during the period 1997-2002. The resistance to antibiotics was determined by disk diffusion method according to National Committee for Clinical Laboratory Standards procedures. The majority of staphylococci isolates were resistant to methicillin, and the proportion of methicillin-resistant Staphylococcus aureus was stable (76.8-81.6%, during the follow-up period. None of the staphylococci isolates were resistant to vancomycin, but there was a very high incidence of high-level resistance of enterococci to aminoglycosides (47.2-72.2%. In 1998, only one strain among enterococci was resistant to vancomycin (Enterococcus faecium, VanA fenotype. Enterococcus spp isolates expressed variable frequency of resistance to ampicillin (15-40.1% during the follow-up period. Among Enterobacteriaceae there were no isolates resistant to imipenem, but dramatic increase of the resistance to ceftriaxone was found from 35.9% in 1997 to 95.9% in 2002 (p<0.001. Extended spectrum beta-lactamases production was found in all the species of enterobacteria isolates. Resistance to imipenem was observed in Acinetobacter spp isolates in 2002 for the first time. Pseudomonas spp isolates expressed high and very variable resistance to all antibiotics tested during the follow-up period.

  19. Antimicrobial resistance in bacteria from breeding dogs housed in kennels with differing neonatal mortality and use of antibiotics.

    Science.gov (United States)

    Milani, C; Corrò, M; Drigo, M; Rota, A

    2012-10-01

    This work examines the antimicrobial resistance of potentially pathogenic bacteria (Staphylococcus pseudintermedius, Streptococcus canis, Escherichia coli) found in the vaginal tract in prepartum mammary secretions and postpartum milk of bitches housed in breeding kennels (N = 20; 92 bitches). The kennels were divided into three categories: no routine antimicrobial administration around parturition (category 1); routine administration of one antibiotic around parturition (category 2); routine administration of multiple antimicrobials around parturition (category 3). Bacteriological cultures and antibiotic susceptibility tests were performed on vaginal specimens, prepartum mammary secretions, and postpartum milk. Stillbirths and neonatal deaths were recorded for each whelping and analyzed as "within-litter stillbirths" and "within-litter neonatal deaths" according to kennel category, by Pearson χ(2) test and the Kruskal-Wallis nonparametric test, respectively. The frequency of isolation and antimicrobial resistance of bacteria were analyzed according to kennel category by Pearson χ(2) test. Kennel category was not significantly associated with differing numbers of stillbirths or neonatal death events, nor was the frequency of isolation of potentially pathogenic bacteria in the three kennel categories significantly different. Kennel category 3 had a significantly higher frequency of isolation of multiresistant gram-positive bacterial strains. Our results show that intense administration of antibiotics to breeding bitches does not effectively reduce neonatal mortality; on the contrary, it induces multiresistance in potentially pathogenic bacteria. Breeders and veterinarians should be aware of the risk of selecting pathogenic bacteria by uncontrolled treatment in prepartum bitches. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Antibiotic resistance genes in anaerobic bacteria isolated from primary dental root canal infections.

    Science.gov (United States)

    Rôças, Isabela N; Siqueira, José F

    2012-12-01

    Fourty-one bacterial strains isolated from infected dental root canals and identified by 16S rRNA gene sequence were screened for the presence of 14 genes encoding resistance to beta-lactams, tetracycline and macrolides. Thirteen isolates (32%) were positive for at least one of the target antibiotic resistance genes. These strains carrying at least one antibiotic resistance gene belonged to 11 of the 26 (42%) infected root canals sampled. Two of these positive cases had two strains carrying resistance genes. Six out of 7 Fusobacterium strains harbored at least one of the target resistance genes. One Dialister invisus strain was positive for 3 resistance genes, and 4 other strains carried two of the target genes. Of the 6 antibiotic resistance genes detected in root canal strains, the most prevalent were blaTEM (17% of the strains), tetW (10%), and ermC (10%). Some as-yet-uncharacterized Fusobacterium and Prevotella isolates were positive for blaTEM, cfxA and tetM. Findings demonstrated that an unexpectedly large proportion of dental root canal isolates, including as-yet-uncharacterized strains previously regarded as uncultivated phylotypes, can carry antibiotic resistance genes. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Antibiotic Resistance

    DEFF Research Database (Denmark)

    Hansen, Malene Plejdrup; Hoffmann, Tammy C; McCullough, Amanda R

    2015-01-01

    hygiene, and possibly vaccination and exercise, may be effective. Also, a large range of complementary and alternative medicines (e.g. zinc, vitamin C and probiotics) are proposed for preventing and treating ARIs, but evidence for efficacy is scarce. General practitioners' (GPs) attitudes towards...... wrong. Shared decision making might be a solution, as it enables clinician and patient to participate jointly in making a health decision, having discussed the options together with the evidence for their harms as well as benefits. Furthermore, GPs' diagnostic uncertainty - often leading...... will greatly improve the use of antibiotics for ARIs. However, used in concert, combinations are likely to enable clinicians and health care systems to implement the strategies that will reduce antimicrobial resistance in the future....

  2. Sustainability of Water Reclamation: Long-Term Recharge with Reclaimed Wastewater Does Not Enhance Antibiotic Resistance in Sediment Bacteria

    Directory of Open Access Journals (Sweden)

    Jean E. McLain

    2014-03-01

    Full Text Available Wastewater reclamation for municipal irrigation is an increasingly attractive option for extending water supplies. However, public health concerns include the potential for development of antibiotic resistance (AR in environmental bacteria after exposure to residual pharmaceuticals in reclaimed water. Though scientific studies have reported high levels of AR in soils irrigated with wastewater, these works often fail to address the soil resistome, or the natural occurrence of AR. This study compared AR patterns in sediment Enterococcus isolated from water storage basins containing either reclaimed water or groundwater in central Arizona. Resistance to 16 antibiotics was quantified in isolates to a depth of 30 cm. Results reveal high levels of resistance to certain antibiotics, including lincomycin, ciprofloxacin, and erythromycin, exists in sediments regardless of the water source (groundwater, reclaimed water, and higher AR was not detectable in reclaimed water sediments. Furthermore, multiple-antibiotic-resistance (MAR was substantially reduced in isolates from reclaimed water sediments, compared to freshwater sediment isolates. Comparing the development of AR in sediment bacteria at these two sites will increase awareness of the environmental and public health impacts of using reclaimed water for irrigation of municipal areas, and illustrates the necessity for control sites in studies examining AR development in environmental microbiota.

  3. Extended spectrum β-lactamases, carbapenemases and mobile genetic elements responsible for antibiotics resistance in Gram-negative bacteria.

    Science.gov (United States)

    El Salabi, Allaaeddin; Walsh, Timothey R; Chouchani, Chedly

    2013-05-01

    Infectious diseases due to Gram-negative bacteria are a leading cause of morbidity and mortality worldwide. Antimicrobial agents represent one major therapeutic tools implicated to treat these infections. The misuse of antimicrobial agents has resulted in the emergence of resistant strains of Gram-negatives in particular Enterobacteriaceae and non-fermenters; they have an effect not only on a human but on the public health when bacteria use the resistance mechanisms to spread in the hospital environment and to the community outside the hospitals by means of mobile genetic elements. Gram-negative bacteria have become increasingly resistant to antimicrobial agents. They have developed several mechanisms by which they can withstand to antimicrobials, these mechanisms include the production of Extended-spectrum β-lactamases (ESBLs) and carbapenemases, furthermore, Gram-negative bacteria are now capable of spreading such resistance between members of the family Enterobacteriaceae and non-fermenters using mobile genetic elements as vehicles for such resistance mechanisms rendering antibiotics useless. Therefore, addressing the issue of mechanisms of antimicrobial resistance is considered one of most urgent priorities. This review will help to illustrate different resistance mechanisms; ESBLs, carbapenemases encoded by genes carried by mobile genetic elements, which are used by Gram-negative bacteria to escape antimicrobial effect.

  4. Isolation of Environmental Bacteria from Surface and Drinking Water in Mafikeng, South Africa, and Characterization Using Their Antibiotic Resistance Profiles

    Directory of Open Access Journals (Sweden)

    Suma George Mulamattathil

    2014-01-01

    Full Text Available The aim of this study was to isolate and identify environmental bacteria from various raw water sources as well as the drinking water distributions system in Mafikeng, South Africa, and to determine their antibiotic resistance profiles. Water samples from five different sites (raw and drinking water were analysed for the presence of faecal indicator bacteria as well as Aeromonas and Pseudomonas species. Faecal and total coliforms were detected in summer in the treated water samples from the Modimola dam and in the mixed water samples, with Pseudomonas spp. being the most prevalent organism. The most prevalent multiple antibiotic resistance phenotype observed was KF-AP-C-E-OT-K-TM-A. All organisms tested were resistant to erythromycin, trimethoprim, and amoxicillin. All isolates were susceptible to ciprofloxacin and faecal coliforms and Pseudomonas spp. to neomycin and streptomycin. Cluster analysis based on inhibition zone diameter data suggests that the isolates had similar chemical exposure histories. Isolates were identified using gyrB, toxA, ecfX, aerA, and hylH gene fragments and gyrB, ecfX, and hylH fragments were amplified. These results demonstrate that (i the drinking water from Mafikeng contains various bacterial species and at times faecal and total coliforms. (ii The various bacteria are resistant to various classes of antibiotics.

  5. High resistance rate against 15 different antibiotics in aerobic gram-negative bacteria isolates of cardiology intensive care unit patients

    Directory of Open Access Journals (Sweden)

    Küçükates E

    2002-01-01

    Full Text Available Aerobic gram negative bacteria were isolated and examined microbiologically from various clinical samples of 602 patients hospitalized between January 1997 and December 2000 in surgical and coronary intensive care units (ICUs. A total of 827 isolates were obtained from 602 patients. The majority of microorganisms were isolated from the respiratory tract (50.3% and blood (39.9%. Pseudomonas spp. were the most frequently isolated gram negative species (32.7%, followed by Acinetobacter spp. (24.0% and Klebsiella pneumoniae (19.4%. High resistance rates to all antibiotics studied were observed. Imipenem and meropenem were the most effective antibiotics against gram negatives.

  6. Multi-antibiotic resistant bacteria in frozen food (ready to cook food) of animal origin sold in Dhaka, Bangladesh

    OpenAIRE

    Sultana, Fouzia; Kamrunnahar,; Afroz, Hafsa; Jahan, Afroz; Fakruddin, Md.; Datta, Suvamoy

    2014-01-01

    Objective: To investigate the bacterial load and antibiotic resistance pattern of bacterial isolates obtained from (ready to cook) frozen food samples of animal origin in Dhaka, Bangladesh. Methods: A total of 20 samples of frozen ready to cook food of animal origin were purchased from different separate grocery stores in Dhaka, Bangladesh. Bacteria were isolated and identified based on the basis of biochemical properties. Results: A total of 57 isolates has been isolated from 20 sample...

  7. The effects of low-level ionizing radiation and copper exposure on the incidence of antibiotic resistance in lentic biofilm bacteria.

    Science.gov (United States)

    McArthur, J Vaun; Dicks, Christian A; Bryan, A Lawrence; Tuckfield, R Cary

    2017-09-01

    Environmental reservoirs of antibiotic resistant bacteria are poorly understood. Understanding how the environment selects for resistance traits in the absence of antibiotics is critical in developing strategies to mitigate this growing menace. Indirect or co-selection of resistance by environmental pollution has been shown to increase antibiotic resistance. However no attention has been given to the effects of low-level ionizing radiation or the interactions between radiation and heavy metals on the maintenance or selection for antibiotic resistance (AR) traits. Here we explore the effect of radiation and copper on antibiotic resistance. Bacteria were collected from biofilms in two ponds - one impacted by low-level radiocesium and the other an abandoned farm pond. Through laboratory controlled experiments we examined the effects of increasing concentrations of copper on the incidence of antibiotic resistance. Differences were detected in the resistance profiles of the controls from each pond. Low levels (0.01 mM) of copper sulfate increased resistance but 0.5 mM concentrations of copper sulfate depressed the AR response in both ponds. A similar pattern was observed for levels of multiple antibiotic resistance per isolate. The first principal component response of isolate exposure to multiple antibiotics showed significant differences among the six isolate treatment combinations. These differences were clearly visualized through a discriminant function analysis, which showed distinct antibiotic resistance response patterns based on the six treatment groups. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Mechanisms of Antibiotic Resistance

    Science.gov (United States)

    Munita, Jose M.; Arias, Cesar A.

    2015-01-01

    Emergence of resistance among the most important bacterial pathogens is recognized as a major public health threat affecting humans worldwide. Multidrug-resistant organisms have emerged not only in the hospital environment but are now often identified in community settings, suggesting that reservoirs of antibiotic-resistant bacteria are present outside the hospital. The bacterial response to the antibiotic “attack” is the prime example of bacterial adaptation and the pinnacle of evolution. “Survival of the fittest” is a consequence of an immense genetic plasticity of bacterial pathogens that trigger specific responses that result in mutational adaptations, acquisition of genetic material or alteration of gene expression producing resistance to virtually all antibiotics currently available in clinical practice. Therefore, understanding the biochemical and genetic basis of resistance is of paramount importance to design strategies to curtail the emergence and spread of resistance and devise innovative therapeutic approaches against multidrug-resistant organisms. In this chapter, we will describe in detail the major mechanisms of antibiotic resistance encountered in clinical practice providing specific examples in relevant bacterial pathogens. PMID:27227291

  9. Addressing resistance to antibiotics in systematic reviews of antibiotic interventions

    NARCIS (Netherlands)

    Leibovici, Leonard; Paul, Mical; Garner, Paul; Sinclair, David J; Afshari, Arash; Pace, Nathan Leon; Cullum, Nicky; Williams, Hywel C; Smyth, Alan; Skoetz, Nicole; Del Mar, Chris; Schilder, Anne G M; Yahav, Dafna; Tovey, David

    Antibiotics are among the most important interventions in healthcare. Resistance of bacteria to antibiotics threatens the effectiveness of treatment. Systematic reviews of antibiotic treatments often do not address resistance to antibiotics even when data are available in the original studies. This

  10. Inactivation/reactivation of antibiotic-resistant bacteria by a novel UVA/LED/TiO2 system.

    Science.gov (United States)

    Xiong, Pei; Hu, Jiangyong

    2013-09-01

    In this study, an effective photocatalytic disinfection system was established using the newly emerged high power UVA/LED lamp. Crystallizing dish coated with TiO2 was prepared by 32-times impregnation-drying processes, and served as the supporting container for water samples. This study focused on the application of this UVA/LED system for the photocatalytic disinfection of selected antibiotic-resistant bacteria, Escherichia coli ATCC 700891. The disinfection performances were studied under various light intensities and illumination modes. Results show that higher light intensity could reach more significant inactivation of E. coli ATCC 700891. With the same UV dose, log-removal of antibiotic-resistant bacteria decreased with circle time in the studied range, while increased with duty circle. A "residual disinfecting effect" was found in the following dark period for bacteria collected at different phases of photocatalytic process. Residual disinfecting effect was found not significant for bacteria with 30 min periodic illumination. While residual disinfecting effect could kill almost all bacteria after 90 min UV periodic illumination within the following 240 min dark period. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Effect of biochar amendment on the control of soil sulfonamides, antibiotic-resistant bacteria, and gene enrichment in lettuce tissues.

    Science.gov (United States)

    Ye, Mao; Sun, Mingming; Feng, Yanfang; Wan, Jinzhong; Xie, Shanni; Tian, Da; Zhao, Yu; Wu, Jun; Hu, Feng; Li, Huixin; Jiang, Xin

    2016-05-15

    Considering the potential threat of vegetables growing in antibiotic-polluted soil with high abundance of antibiotic-resistant genes (ARGs) against human health through the food chain, it is thus urgent to develop novel control technology to ensure vegetable safety. In the present work, pot experiments were conducted in lettuce cultivation to assess the impedance effect of biochar amendment on soil sulfonamides (SAs), antibiotic-resistant bacteria (ARB), and ARG enrichment in lettuce tissues. After 100 days of cultivation, lettuce cultivation with biochar amendment exhibited the greatest soil SA dissipation as well as the significant improvement of lettuce growth indices, with residual soil SAs mainly existing as the tightly bound fraction. Moreover, the SA contents in roots and new/old leaves were reduced by one to two orders of magnitude compared to those without biochar amendment. In addition, isolate counts for SA-resistant bacterial endophytes in old leaves and sul gene abundances in roots and old leaves also decreased significantly after biochar application. However, neither SA resistant bacteria nor sul genes were detected in new leaves. It was the first study to demonstrate that biochar amendment can be a practical strategy to protect lettuce safety growing in SA-polluted soil with rich ARB and ARGs. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Antibiotic- and heavy-metal resistance in bacteria isolated from deep subsurface in El Callao region, Venezuela

    Directory of Open Access Journals (Sweden)

    Maura Lina Rojas Pirela

    2014-07-01

    Full Text Available Título en ingles: Antibiotic- and heavy-metal resistance in bacteria isolated from deep subsurface in El Callao region, Venezuela Título corto: Antibiotic and metal resistance in bacteria from deep subsurface Título en español: Resistencia a antibioticos y metals pesados en bacterias aisladas de subsuelo en la región El Callao, Venezuela Resumen:  Se investigó el efecto de la contaminación con mercurio (Hg en las comunidades bacterianas del subsuelo profundo en la región de El Callao (Estado Bolívar, Venezuela. Se estudiaron comunidades bacterianas de dos niveles de profundidad (-288 m y -388 m en una mina de oro con el propósito de describir las características más relevantes de las bacterias indígenas cultivables que colonizaban esta mina. Se evaluaron los patrones de resistencia a antibióticos y metales pesados, presencia del gen merA y plásmidos en aislados resistentes. Se encontró una elevada frecuencia de bacterias indígenas resistentes al Hg y otros metales pesados. De 76 aislados Hg-resistentes probados 73.7 % fueron adicionalmente resistentes a ampicilina; 86.8 % a cloranfenicol; 67.1 % a tetraciclina; 56.6 % a estreptomicina y 51.3 % a kanamicina. Además, se encontró que 40.74 % (-328 m y 26.53 % (-388 m de las bacterias Hg-resistentes fueron simultáneamente resistentes tanto a cuatro como a cinco de estos antibióticos. Se detectó la presencia de plásmidos de alto y bajo peso molecular y, a pesar de que los aislados mostraban resistencia a compuestos mercuriales, la presencia del gen merA fue detectada solo en 71.05 % de los cepas. Estos resultados sugieren que la exposición a Hg podría ser una presión selectiva en la proliferación de bacterias resistentes a antibióticos y promover el mantenimiento y propagación de estos genes de resistencia. Sin embargo, la existencia de tales resistencias a estas profundidades podría también apoyar la idea de que la resistencia a antibióticos en estas bacterias es

  13. H2O2 and/or TiO2 photocatalysis under UV irradiation for the removal of antibiotic resistant bacteria and their antibiotic resistance genes

    International Nuclear Information System (INIS)

    Guo, Changsheng; Wang, Kai; Hou, Song; Wan, Li; Lv, Jiapei; Zhang, Yuan; Qu, Xiaodong; Chen, Shuyi; Xu, Jian

    2017-01-01

    Highlights: • TiO 2 thin film was successfully synthesized for treating ARB and ARGs from water. • More than 5.5 log units of ARB reduction was achieved by TiO 2 under UV irradiation. • With TiO 2 , ARGs were reduced by more than 5 log units under UV irradiation. • TiO 2 could remove both intracellular and extracellular forms of ARGs. - Abstract: Inactivating antibiotic resistant bacteria (ARB) and removing antibiotic resistance genes (ARGs) are very important to prevent their spread into the environment. Previous efforts have been taken to eliminate ARB and ARGs from aqueous solution and sludges, however, few satisfying results have been obtained. This study investigated whether photocatalysis by TiO 2 was able to reduce the two ARGs, mecA and ampC, within the host ARB, methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, respectively. The addition of H 2 O 2 and matrix effect on the removal of ARB and ARGs were also studied. TiO 2 thin films showed great effect on both ARB inactivation and ARGs removal. Approximately 4.5-5.0 and 5.5–5.8 log ARB reductions were achieved by TiO 2 under 6 and 12 mJ/cm 2 UV 254 fluence dose, respectively. For ARGs, 5.8 log mecA reduction and 4.7 log ampC reduction were achieved under 120 mJ/cm 2 UV 254 fluence dose in the presence of TiO 2 . Increasing dosage of H 2 O 2 enhanced the removal efficiencies of ARB and ARGs. The results also demonstrated that photocatalysis by TiO 2 was capable of removing both intracellular and extracellular forms of ARGs. This study provided a potential alternative method for the removal of ARB and ARGs from aqueous solution.

  14. Antibacterial and Antibiotic-Modifying Activity of Methanol Extracts from Six Cameroonian Food Plants against Multidrug-Resistant Enteric Bacteria

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    Joachim K. Dzotam

    2017-01-01

    Full Text Available The present work was designed to investigate the antibacterial activities of methanol extracts from six Cameroonian edible plants and their synergistic effects with some commonly used antibiotics against multidrug-resistant (MDR Gram-negative bacteria expressing active efflux pumps. The extracts were subjected to qualitative phytochemical screening and the microdilution broth method was used for antibacterial assays. The results of phytochemical tests indicate that all tested crude extracts contained polyphenols, flavonoids, triterpenes, and steroids. Extracts displayed selective antibacterial activities with the minimal inhibitory concentration (MIC values ranging from 32 to 1024 μg/mL. The lowest MIC value (32 μg/mL was recorded with Coula edulis extract against E. coli AG102 and K. pneumoniae K2 and with Mangifera indica bark extract against P. aeruginosa PA01 and Citrus sinensis extract against E. coli W3110 which also displayed the best MBC (256 μg/mL value against E. coli ATCC8739. In combination with antibiotics, extracts from M. indica leaves showed synergistic effects with 75% (6/8 of the tested antibiotics against more than 80% of the tested bacteria. The findings of the present work indicate that the tested plants may be used alone or in combination in the treatment of bacterial infections including the multidrug-resistant bacteria.

  15. Selection of antibiotic resistance at very low antibiotic concentrations

    OpenAIRE

    Sandegren, Linus

    2014-01-01

    Human use of antibiotics has driven the selective enrichment of pathogenic bacteria resistant to clinically used drugs. Traditionally, the selection of resistance has been considered to occur mainly at high, therapeutic levels of antibiotics, but we are now beginning to understand better the importance of selection of resistance at low levels of antibiotics. The concentration of an antibiotic varies in different body compartments during treatment, and low concentrations of antibiotics are fou...

  16. Fate of antibiotic resistance bacteria and genes during enhanced anaerobic digestion of sewage sludge by microwave pretreatment.

    Science.gov (United States)

    Tong, Juan; Liu, Jibao; Zheng, Xiang; Zhang, Junya; Ni, Xiaotang; Chen, Meixue; Wei, Yuansong

    2016-10-01

    The fate of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) were investigated during the sludge anaerobic digestion (AD) with microwave-acid (MW-H), microwave (MW) and microwave-H2O2-alkaline (MW-H2O2) pretreatments. Results showed that combined MW pretreatment especially for the MW-H pretreatment could efficiently reduce the ARB concentration, and most ARG concentrations tended to attenuate during the pretreatment. The subsequent AD showed evident removal of the ARB, but most ARGs were enriched after AD. Only the concentration of tetX kept continuous declination during the whole sludge treatment. The total ARGs concentration showed significant correlation with 16S rRNA during the pretreatment and AD. Compared with unpretreated sludge, the AD of MW and MW-H2O2 pretreated sludge presented slightly better ARB and ARGs reduction efficiency. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

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    Palloma Rodrigues Marinho

    2009-08-01

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

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

    Science.gov (United States)

    Marinho, Palloma Rodrigues; Moreira, Ana Paula Barbosa; Pellegrino, Flávia Lúcia Piffano Costa; Muricy, Guilherme; Bastos, Maria do Carmo de Freire; Santos, Kátia Regina Netto dos; Giambiagi-deMarval, Marcia; Laport, Marinella Silva

    2009-08-01

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

  19. An unusual class of anthracyclines potentiate Gram-positive antibiotics in intrinsically resistant Gram-negative bacteria.

    Science.gov (United States)

    Cox, Georgina; Koteva, Kalinka; Wright, Gerard D

    2014-07-01

    An orthogonal approach taken towards novel antibacterial drug discovery involves the identification of small molecules that potentiate or enhance the activity of existing antibacterial agents. This study aimed to identify natural-product rifampicin adjuvants in the intrinsically resistant organism Escherichia coli. E. coli BW25113 was screened against 1120 actinomycete fermentation extracts in the presence of subinhibitory (2 mg/L) concentrations of rifampicin. The active molecule exhibiting the greatest rifampicin potentiation was isolated using activity-guided methods and identified using mass and NMR spectroscopy. Susceptibility testing and biochemical assays were used to determine the mechanism of antibiotic potentiation. The anthracycline Antibiotic 301A(1) was isolated from the fermentation broth of a strain of Streptomyces (WAC450); the molecule was shown to be highly synergistic with rifampicin (fractional inhibitory concentration index = 0.156) and moderately synergistic with linezolid (FIC index = 0.25) in both E. coli and Acinetobacter baumannii. Activity was associated with inhibition of efflux and the synergistic phenotype was lost when tested against E. coli harbouring mutations within the rpoB gene. Structure-activity relationship studies revealed that other anthracyclines do not synergize with rifampicin and removal of the sugar moiety of Antibiotic 301A(1) abolishes activity. Screening only a subsection of our natural product library identified a small-molecule antibiotic adjuvant capable of sensitizing Gram-negative bacteria to antibiotics to which they are ordinarily intrinsically resistant. This result demonstrates the great potential of this approach in expanding antibiotic effectiveness in the face of the growing challenge of resistance in Gram-negatives. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. An unusual class of anthracyclines potentiate Gram-positive antibiotics in intrinsically resistant Gram-negative bacteria

    Science.gov (United States)

    Cox, Georgina; Koteva, Kalinka; Wright, Gerard D.

    2014-01-01

    Objectives An orthogonal approach taken towards novel antibacterial drug discovery involves the identification of small molecules that potentiate or enhance the activity of existing antibacterial agents. This study aimed to identify natural-product rifampicin adjuvants in the intrinsically resistant organism Escherichia coli. Methods E. coli BW25113 was screened against 1120 actinomycete fermentation extracts in the presence of subinhibitory (2 mg/L) concentrations of rifampicin. The active molecule exhibiting the greatest rifampicin potentiation was isolated using activity-guided methods and identified using mass and NMR spectroscopy. Susceptibility testing and biochemical assays were used to determine the mechanism of antibiotic potentiation. Results The anthracycline Antibiotic 301A1 was isolated from the fermentation broth of a strain of Streptomyces (WAC450); the molecule was shown to be highly synergistic with rifampicin (fractional inhibitory concentration index = 0.156) and moderately synergistic with linezolid (FIC index = 0.25) in both E. coli and Acinetobacter baumannii. Activity was associated with inhibition of efflux and the synergistic phenotype was lost when tested against E. coli harbouring mutations within the rpoB gene. Structure–activity relationship studies revealed that other anthracyclines do not synergize with rifampicin and removal of the sugar moiety of Antibiotic 301A1 abolishes activity. Conclusions Screening only a subsection of our natural product library identified a small-molecule antibiotic adjuvant capable of sensitizing Gram-negative bacteria to antibiotics to which they are ordinarily intrinsically resistant. This result demonstrates the great potential of this approach in expanding antibiotic effectiveness in the face of the growing challenge of resistance in Gram-negatives. PMID:24627312

  1. Recovery of metallo-tolerant and antibiotic resistant psychrophilic bacteria from Siachen glacier, Pakistan.

    Directory of Open Access Journals (Sweden)

    Muhammad Rafiq

    Full Text Available Cultureable bacterial diversity of previously unexplored Siachen glacier, Pakistan, was studied. Out of 50 isolates 33 (66% were Gram negative and 17 (34% Gram positive. About half of the isolates were pigment producers and were able to grow at 4-37°C. 16S rRNA gene sequences revealed Gram negative bacteria dominated by Proteobacteria (especially γ-proteobacteria and β-proteobacteria and Flavobacteria. The genus Pseudomonas (51.51%, 17 was dominant among γ- proteobacteria. β-proteobacteria constituted 4 (12.12% Alcaligenes and 4 (12.12% Janthinobacterium strains. Among Gram positive bacteria, phylum Actinobacteria, Rhodococcus (23.52%, 4 and Arthrobacter (23.52%, 4 were the dominating genra. Other bacteria belonged to Phylum Firmicutes with representative genus Carnobacterium (11.76%, 2 and 4 isolates represented 4 genera Bacillus, Lysinibacillus, Staphylococcus and Planomicrobium. Most of the Gram negative bacteria were moderate halophiles, while most of the Gram positives were extreme halophiles and were able to grow up to 6.12 M of NaCl. More than 2/3 of the isolates showed antimicrobial activity against multidrug resistant S. aureus, E. coli, Klebsiella pneumonia, Enterococcus faecium, Candida albicans, Aspergillus flavus and Aspergillus fumigatus and ATCC strains. Gram positive bacteria (94.11% were more resistant to heavy metals as compared to Gram negative (78.79% and showed maximum tolerance against iron and least tolerance against mercury.

  2. Bacteria isolated from pristine high altitude environments in the Argentinean Andean wetlands: plasmid profile and multiple antibiotic resistance

    International Nuclear Information System (INIS)

    Dib, J.R.; Martinez, M.A.; Sineriz, F.; Farias, M.E.

    2005-01-01

    Full text: Andean wetlands, placed in the North-Western Argentine at 4,600 m altitude, are attractive for both, environmental and biotechnology studies. Most of these wetlands are completely remote and inaccessible, having a high salinity and metal contents, a wide range of daily temperature changes, and an important intensity of solar UV-B radiation. Bacteria isolated from these environments were identified by 16SrDNA sequence and resulted in Gram-positive colored bacteria. Interesting features, to our knowledge never reported so far from bacteria isolates from these pristine high altitude lake-environments, such as similar plasmids profiles and multiple antibiotic resistances are the focus of this work. At least two plasmids were found in all isolates studied by using modifications of the alkaline Iysis method. Their preliminary characterization in this work includes size, incompatibility group through PCR, genetic transference to suitable hosts by transformation and conjugation, and studies of possible relationships of them with antibiotic resistances. (author)

  3. Occurrence of antibiotic and metal resistance in bacteria from organs of river fish

    International Nuclear Information System (INIS)

    Pathak, S.P.; Gopal, K.

    2005-01-01

    Bacterial populations in some organs, viz., liver, spleen, kidney, gill, and arborescent organ of the catfish Clarias batrachus were enumerated followed by determination of resistance for antibiotics and metals. The total viable counts in these organs, observed, were 2.24x10 4 , 2.08x10 4 , 1.44x10 4 , 1.23x10 4 , and 6.40x10 3 colony-forming units/mL, respectively. The random bacterial isolates from these fish organs showed resistance in decreasing order for colistin (98%), ampicillin (82%), gentamycin (34%), carbenicillin (28%), tetracyline (20%), streptomycin (12%), and ciprofloxacin (02%). Most of the isolates exhibited an increasing order of tolerance for the metals (μg/mL) copper (100), lead (200), manganese (400), cadmium (200), and chromium (50), with minimum inhibitory concentration (MIC) ranging from <50 to 1600 μg/mL. These observations indicate that the significant occurrence of bacterial population in organs of fish with high incidence of resistance for antibiotics and metals may pose risk to fish fauna and public health

  4. The Prehistory of Antibiotic Resistance.

    Science.gov (United States)

    Perry, Julie; Waglechner, Nicholas; Wright, Gerard

    2016-06-01

    Antibiotic resistance is a global problem that is reaching crisis levels. The global collection of resistance genes in clinical and environmental samples is the antibiotic "resistome," and is subject to the selective pressure of human activity. The origin of many modern resistance genes in pathogens is likely environmental bacteria, including antibiotic producing organisms that have existed for millennia. Recent work has uncovered resistance in ancient permafrost, isolated caves, and in human specimens preserved for hundreds of years. Together with bioinformatic analyses on modern-day sequences, these studies predict an ancient origin of resistance that long precedes the use of antibiotics in the clinic. Understanding the history of antibiotic resistance is important in predicting its future evolution. Copyright © 2016 Cold Spring Harbor Laboratory Press; all rights reserved.

  5. Prevalence of bacteria resistant to antibiotics and/or biocides on meat processing plant surfaces throughout meat chain production.

    Science.gov (United States)

    Lavilla Lerma, Leyre; Benomar, Nabil; Gálvez, Antonio; Abriouel, Hikmate

    2013-02-01

    In order to investigate the prevalence of resistant bacteria to biocides and/or antibiotics throughout meat chain production from sacrifice till end of production line, samples from various surfaces of a goat and lamb slaughterhouse representative of the region were analyzed by the culture dependent approach. Resistant Psychrotrophs (n=255 strains), Pseudomonas sp. (n=166 strains), E. coli (n=23 strains), Staphylococcus sp. (n=17 strains) and LAB (n=82 represented mainly by Lactobacillus sp.) were isolated. Resistant psychrotrophs and pseudomonads (47 and 29%, respectively) to different antimicrobials were frequently detected in almost all areas of meat processing plant regardless the antimicrobial used, although there was a clear shift in the spectrum of other bacterial groups and for this aim such resistance was determined according to several parameters: antimicrobial tested, sampling zone and the bacterial group. Correlation of different parameters was done using a statistical tool "Principal component analysis" (PCA) which determined that quaternary ammonium compounds and hexadecylpyridinium were the most relevant biocides for resistance in Pseudomonas sp., while ciprofloxacin and hexachlorophene were more relevant for psychrotrophs, LAB, and in lesser extent Staphylococcus sp. and Escherichia coli. On the other hand, PCA of sampling zones determined that sacrifice room (SR) and cutting room (CR) considered as main source of antibiotic and/or biocide resistant bacteria showed an opposite behaviour concerning relevance of antimicrobials to determine resistance being hexadecylpyridinium, cetrimide and chlorhexidine the most relevant in CR, while hexachlorophene, oxonia 6P and PHMG the most relevant in SR. In conclusion, rotational use of the relevant biocides as disinfectants in CR and SR is recommended in an environment which is frequently disinfected. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Effect of biochar amendment on the control of soil sulfonamides, antibiotic-resistant bacteria, and gene enrichment in lettuce tissues

    International Nuclear Information System (INIS)

    Ye, Mao; Sun, Mingming; Feng, Yanfang; Wan, Jinzhong; Xie, Shanni; Tian, Da; Zhao, Yu; Wu, Jun; Hu, Feng; Li, Huixin; Jiang, Xin

    2016-01-01

    Highlights: • Biochar can prevent soil sulfonamides from accumulating in lettuce tissues. • ARB enrichment in lettuce tissues decreased significantly after biochar amendment. • Impedance effect of biochar addition on soil ARGs was also quite effective. • Biochar application can be a practical strategy to protect vegetable safety. - Abstract: Considering the potential threat of vegetables growing in antibiotic-polluted soil with high abundance of antibiotic-resistant genes (ARGs) against human health through the food chain, it is thus urgent to develop novel control technology to ensure vegetable safety. In the present work, pot experiments were conducted in lettuce cultivation to assess the impedance effect of biochar amendment on soil sulfonamides (SAs), antibiotic-resistant bacteria (ARB), and ARG enrichment in lettuce tissues. After 100 days of cultivation, lettuce cultivation with biochar amendment exhibited the greatest soil SA dissipation as well as the significant improvement of lettuce growth indices, with residual soil SAs mainly existing as the tightly bound fraction. Moreover, the SA contents in roots and new/old leaves were reduced by one to two orders of magnitude compared to those without biochar amendment. In addition, isolate counts for SA-resistant bacterial endophytes in old leaves and sul gene abundances in roots and old leaves also decreased significantly after biochar application. However, neither SA resistant bacteria nor sul genes were detected in new leaves. It was the first study to demonstrate that biochar amendment can be a practical strategy to protect lettuce safety growing in SA-polluted soil with rich ARB and ARGs.

  7. Effect of biochar amendment on the control of soil sulfonamides, antibiotic-resistant bacteria, and gene enrichment in lettuce tissues

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Mao [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Sun, Mingming [Soil Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Feng, Yanfang, E-mail: fengyanfang@163.com [Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing 210014 (China); Wan, Jinzhong [Nanjing Institute of Environmental Science, Ministry of Environmental Protection of China, Nanjing 210042 (China); Xie, Shanni; Tian, Da [Soil Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Zhao, Yu [Collaborative Innovation Center of Advanced Microstructures, Jiangsu Provincial Key Laboratory of Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 (China); Wu, Jun; Hu, Feng; Li, Huixin [Soil Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Jiang, Xin, E-mail: Jiangxin@issas.ac.cn [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China)

    2016-05-15

    Highlights: • Biochar can prevent soil sulfonamides from accumulating in lettuce tissues. • ARB enrichment in lettuce tissues decreased significantly after biochar amendment. • Impedance effect of biochar addition on soil ARGs was also quite effective. • Biochar application can be a practical strategy to protect vegetable safety. - Abstract: Considering the potential threat of vegetables growing in antibiotic-polluted soil with high abundance of antibiotic-resistant genes (ARGs) against human health through the food chain, it is thus urgent to develop novel control technology to ensure vegetable safety. In the present work, pot experiments were conducted in lettuce cultivation to assess the impedance effect of biochar amendment on soil sulfonamides (SAs), antibiotic-resistant bacteria (ARB), and ARG enrichment in lettuce tissues. After 100 days of cultivation, lettuce cultivation with biochar amendment exhibited the greatest soil SA dissipation as well as the significant improvement of lettuce growth indices, with residual soil SAs mainly existing as the tightly bound fraction. Moreover, the SA contents in roots and new/old leaves were reduced by one to two orders of magnitude compared to those without biochar amendment. In addition, isolate counts for SA-resistant bacterial endophytes in old leaves and sul gene abundances in roots and old leaves also decreased significantly after biochar application. However, neither SA resistant bacteria nor sul genes were detected in new leaves. It was the first study to demonstrate that biochar amendment can be a practical strategy to protect lettuce safety growing in SA-polluted soil with rich ARB and ARGs.

  8. Longitudinal nasopharyngeal carriage and antibiotic resistance of respiratory bacteria in indigenous Australian and Alaska native children with bronchiectasis.

    Directory of Open Access Journals (Sweden)

    Kim M Hare

    Full Text Available BACKGROUND: Indigenous children in Australia and Alaska have very high rates of chronic suppurative lung disease (CSLD/bronchiectasis. Antibiotics, including frequent or long-term azithromycin in Australia and short-term beta-lactam therapy in both countries, are often prescribed to treat these patients. In the Bronchiectasis Observational Study we examined over several years the nasopharyngeal carriage and antibiotic resistance of respiratory bacteria in these two PCV7-vaccinated populations. METHODS: Indigenous children aged 0.5-8.9 years with CSLD/bronchiectasis from remote Australia (n = 79 and Alaska (n = 41 were enrolled in a prospective cohort study during 2004-8. At scheduled study visits until 2010 antibiotic use in the preceding 2-weeks was recorded and nasopharyngeal swabs collected for culture and antimicrobial susceptibility testing. Analysis of respiratory bacterial carriage and antibiotic resistance was by baseline and final swabs, and total swabs by year. RESULTS: Streptococcus pneumoniae carriage changed little over time. In contrast, carriage of Haemophilus influenzae declined and Staphylococcus aureus increased (from 0% in 2005-6 to 23% in 2010 in Alaskan children; these changes were associated with increasing age. Moraxella catarrhalis carriage declined significantly in Australian, but not Alaskan, children (from 64% in 2004-6 to 11% in 2010. While beta-lactam antibiotic use was similar in the two cohorts, Australian children received more azithromycin. Macrolide resistance was significantly higher in Australian compared to Alaskan children, while H. influenzae beta-lactam resistance was higher in Alaskan children. Azithromycin use coincided significantly with reduced carriage of S. pneumoniae, H. influenzae and M. catarrhalis, but increased carriage of S. aureus and macrolide-resistant strains of S. pneumoniae and S. aureus (proportion of carriers and all swabs, in a 'cumulative dose-response' relationship

  9. Antibiotic resistance patterns in fecal bacteria isolated from Christmas shearwater (Puffinus nativitatis) and masked booby (Sula dactylatra) at remote Easter Island.

    Science.gov (United States)

    Ardiles-Villegas, Karen; González-Acuña, Daniel; Waldenström, Jonas; Olsen, Björn; Hernández, Jorge

    2011-09-01

    Antibiotic use and its implications have been discussed extensively in the past decades. This situation has global consequences when antibiotic resistance becomes widespread in the intestinal bacterial flora of stationary and migratory birds. This study investigated the incidence of fecal bacteria and general antibiotic resistance, with special focus on extended spectrum beta-lactamase (ESBL) isolates, in two species of seabirds at remote Easter Island. We identified 11 species of bacteria from masked booby (Sula dactylatra) and Christmas shearwater (Puffinus nativitatis); five species of gram-negative bacilli, four species of Streptococcus (Enterococcus), and 2 species of Staphylococcus. In addition, 6 types of bacteria were determined barely to the genus level. General antibiotic susceptibility was measured in the 30 isolated Enterobacteriaceae to 11 antibiotics used in human and veterinary medicine. The 10 isolates that showed a phenotypic ESBL profile were verified by clavulanic acid inhibition in double mixture discs with cefpodoxime, and two ESBL strains were found, one strain in masked booby and one strain in Christmas shearwater. The two bacteria harboring the ESBL type were identified as Serratia odorifera biotype 1, which has zoonotic importance. Despite minimal human presence in the masked booby and Christmas shearwater habitats, and the extreme geographic isolation of Easter Island, we found several multiresistant bacteria and even two isolates with ESBL phenotypes. The finding of ESBLs has animal and public health significance and is of potential concern, especially because the investigation was limited in size and indicated that antibiotic-resistant bacteria now are distributed globally.

  10. Antibacterial and antibiotic resistance modifying activity of the extracts from Allanblackia gabonensis, Combretum molle and Gladiolus quartinianus against Gram-negative bacteria including multi-drug resistant phenotypes.

    Science.gov (United States)

    Fankam, Aimé G; Kuiate, Jules R; Kuete, Victor

    2015-06-30

    Bacterial resistance to antibiotics is becoming a serious problem worldwide. The discovery of new and effective antimicrobials and/or resistance modulators is necessary to tackle the spread of resistance or to reverse the multi-drug resistance. We investigated the antibacterial and antibiotic-resistance modifying activities of the methanol extracts from Allanblackia gabonensis, Gladiolus quartinianus and Combretum molle against 29 Gram-negative bacteria including multi-drug resistant (MDR) phenotypes. The broth microdilution method was used to determine the minimal inhibitory concentrations (MIC) and minimal bactericidal concentrations (MBC) of the samples meanwhile the standard phytochemical methods were used for the preliminary phytochemical screening of the plant extracts. Phytochemical analysis showed the presence of alkaloids, flavonoids, phenols and tannins in all studied extracts. Other chemical classes of secondary metabolites were selectively presents. Extracts from A. gabonensis and C. molle displayed a broad spectrum of activity with MICs varying from 16 to 1024 μg/mL against about 72.41% of the tested bacteria. The extract from the fruits of A. gabonensis had the best activity, with MIC values below 100 μg/mL on 37.9% of tested bacteria. Percentages of antibiotic-modulating effects ranging from 67 to 100% were observed against tested MDR bacteria when combining the leaves extract from C. molle (at MIC/2 and MIC/4) with chloramphenicol, kanamycin, streptomycin and tetracycline. The overall results of the present study provide information for the possible use of the studied plant, especially Allanblackia gabonensis and Combretum molle in the control of Gram-negative bacterial infections including MDR species as antibacterials as well as resistance modulators.

  11. Impact of fertilizing with raw or anaerobically digested sewage sludge on the abundance of antibiotic-resistant coliforms, antibiotic resistance genes, and pathogenic bacteria in soil and on vegetables at harvest.

    Science.gov (United States)

    Rahube, Teddie O; Marti, Romain; Scott, Andrew; Tien, Yuan-Ching; Murray, Roger; Sabourin, Lyne; Zhang, Yun; Duenk, Peter; Lapen, David R; Topp, Edward

    2014-11-01

    The consumption of crops fertilized with human waste represents a potential route of exposure to antibiotic-resistant fecal bacteria. The present study evaluated the abundance of bacteria and antibiotic resistance genes by using both culture-dependent and molecular methods. Various vegetables (lettuce, carrots, radish, and tomatoes) were sown into field plots fertilized inorganically or with class B biosolids or untreated municipal sewage sludge and harvested when of marketable quality. Analysis of viable pathogenic bacteria or antibiotic-resistant coliform bacteria by plate counts did not reveal significant treatment effects of fertilization with class B biosolids or untreated sewage sludge on the vegetables. Numerous targeted genes associated with antibiotic resistance and mobile genetic elements were detected by PCR in soil and on vegetables at harvest from plots that received no organic amendment. However, in the season of application, vegetables harvested from plots treated with either material carried gene targets not detected in the absence of amendment. Several gene targets evaluated by using quantitative PCR (qPCR) were considerably more abundant on vegetables harvested from sewage sludge-treated plots than on vegetables from control plots in the season of application, whereas vegetables harvested the following year revealed no treatment effect. Overall, the results of the present study suggest that producing vegetable crops in ground fertilized with human waste without appropriate delay or pretreatment will result in an additional burden of antibiotic resistance genes on harvested crops. Managing human exposure to antibiotic resistance genes carried in human waste must be undertaken through judicious agricultural practice. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  12. Effects of biochar on reducing the abundance of oxytetracycline, antibiotic resistance genes, and human pathogenic bacteria in soil and lettuce.

    Science.gov (United States)

    Duan, Manli; Li, Haichao; Gu, Jie; Tuo, Xiaxia; Sun, Wei; Qian, Xun; Wang, Xiaojuan

    2017-05-01

    Antibiotics and antibiotic resistance genes (ARGs) in soil can affect human health via the food chain. Biochar is a soil amendment but its impacts on ARGs and the microbial communities associated with soil and vegetables are unclear. Therefore, we established three lettuce pot culture experiments, i.e., O300: 300 mg/kg oxytetracycline (OTC), BO300: 300 mg/kg OTC + 2% biochar, and a control without OTC or biochar. We found that under BO300, the relative abundances of ARGs were reduced by 51.8%, 43.4%, and 44.1% in lettuce leaves, roots, and soil, respectively, compared with O300. intI1 was highly abundant in soil and lettuce, and it co-occurred with some ARGs (tetW, ermF, and sul1). Redundancy analysis and network analysis indicated that the bacterial community succession was the main mechanism that affected the variations in ARGs and intI1. The reduction of Firmicutes due to the biochar treatment of soil and lettuce was the main factor responsible for the removal of tetracycline resistance genes in leaves. Biochar application led to the disappearance of human pathogenic bacteria (HPB), which was significantly correlated with the abundances of ermF and ermX. In summary, biochar is an effective farmland amendment for reducing the abundances of antibiotics, ARGs, and HPB in order to ensure the safety of vegetables and protect human health. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. What happens in hospitals does not stay in hospitals: antibiotic-resistant bacteria in hospital wastewater systems.

    Science.gov (United States)

    Hocquet, D; Muller, A; Bertrand, X

    2016-08-01

    Hospitals are hotspots for antimicrobial-resistant bacteria (ARB) and play a major role in both their emergence and spread. Large numbers of these ARB will be ejected from hospitals via wastewater systems. In this review, we present quantitative and qualitative data of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli, vancomycin-resistant enterococci and Pseudomonas aeruginosa in hospital wastewaters compared to community wastewaters. We also discuss the fate of these ARB in wastewater treatment plants and in the downstream environment. Published studies have shown that hospital effluents contain ARB, the burden of these bacteria being dependent on their local prevalence. The large amounts of antimicrobials rejected in wastewater exert a continuous selective pressure. Only a few countries recommend the primary treatment of hospital effluents before their discharge into the main wastewater flow for treatment in municipal wastewater treatment plants. Despite the lack of conclusive data, some studies suggest that treatment could favour the ARB, notably ESBL-producing E. coli. Moreover, treatment plants are described as hotspots for the transfer of antibiotic resistance genes between bacterial species. Consequently, large amounts of ARB are released in the environment, but it is unclear whether this release contributes to the global epidemiology of these pathogens. It is reasonable, nevertheless, to postulate that it plays a role in the worldwide progression of antibiotic resistance. Antimicrobial resistance should now be seen as an 'environmental pollutant', and new wastewater treatment processes must be assessed for their capability in eliminating ARB, especially from hospital effluents. Copyright © 2016. Published by Elsevier Ltd.

  14. Surveillance of antibiotic resistance

    Science.gov (United States)

    Johnson, Alan P.

    2015-01-01

    Surveillance involves the collection and analysis of data for the detection and monitoring of threats to public health. Surveillance should also inform as to the epidemiology of the threat and its burden in the population. A further key component of surveillance is the timely feedback of data to stakeholders with a view to generating action aimed at reducing or preventing the public health threat being monitored. Surveillance of antibiotic resistance involves the collection of antibiotic susceptibility test results undertaken by microbiology laboratories on bacteria isolated from clinical samples sent for investigation. Correlation of these data with demographic and clinical data for the patient populations from whom the pathogens were isolated gives insight into the underlying epidemiology and facilitates the formulation of rational interventions aimed at reducing the burden of resistance. This article describes a range of surveillance activities that have been undertaken in the UK over a number of years, together with current interventions being implemented. These activities are not only of national importance but form part of the international response to the global threat posed by antibiotic resistance. PMID:25918439

  15. The Shared Antibiotic Resistome of Soil Bacteria and Human Pathogens

    DEFF Research Database (Denmark)

    Forsberg, Kevin J.; Reyes, Alejandro; Wang, Bin

    2012-01-01

    protocol to assemble short-read sequence data after antibiotic selection experiments, using 12 different drugs in all antibiotic classes, and compared antibiotic resistance gene sequences between soil bacteria and clinically occurring pathogens. Sixteen sequences, representing seven gene products, were...... discovered in farmland soil bacteria within long stretches of perfect nucleotide identity with pathogenic proteobacteria....

  16. Addressing resistance to antibiotics in systematic reviews of antibiotic interventions

    DEFF Research Database (Denmark)

    Leibovici, Leonard; Paul, Mical; Garner, Paul

    2016-01-01

    Antibiotics are among the most important interventions in healthcare. Resistance of bacteria to antibiotics threatens the effectiveness of treatment. Systematic reviews of antibiotic treatments often do not address resistance to antibiotics even when data are available in the original studies....... This omission creates a skewed view, which emphasizes short-term efficacy and ignores the long-term consequences to the patient and other people. We offer a framework for addressing antibiotic resistance in systematic reviews. We suggest that the data on background resistance in the original trials should...... controlled trials or systematic reviews....

  17. High prevalence and resistance rates to antibiotics in anaerobic bacteria in specimens from patients with chronic balanitis.

    Science.gov (United States)

    Boyanova, Lyudmila; Mitev, Angel; Gergova, Galina; Mateev, Grisha; Mitov, Ivan

    2012-08-01

    Aim of the study was to assess both prevalence and antibiotic resistance in anaerobic bacteria from glans penis skin of 70 adults. Strain susceptibility was determined by breakpoint susceptibility test or E test. In 9 asymptomatic, 48 untreated and 13 treated symptomatic patients, anaerobes were found in 22.2%, 70.8% and 53.3%, respectively. Gram-positive strains (GPAs) were 2.2-fold more common than Gram-negative ones. Prevalent Gram-negative (GNAs) and GPAs were Prevotella spp. and anaerobic cocci, respectively. Clostridium difficile strain was found in an untreated patient. In GNAs, resistance rates to amoxicillin, metronidazole, clindamycin, tetracycline, levofloxacin, and amoxicillin/clavulanate were 42.1, 0, 52.6, 53.3, 86.7 and 5.2%, respectively. In GPAs, the resistance rates to metronidazole, clindamycin, tetracycline, levofloxacin and amoxicillin/clavulanate were 18.2, 34.1, 52.6, 36.8 and 0%, respectively. In conclusion, anaerobes were 1.6-fold more frequent in untreated symptomatic patients compared with other patients, suggesting their participation in development of chronic balanitis. GPAs were more common than GNAs. The resistance rates to amoxicillin, clindamycin, tetracycline, and levofloxacin were high. Most active agents were metronidazole and amoxicillin/clavulanate. Resistance in anaerobes varies according to sites of specimens and years of study. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. The potential implications of reclaimed wastewater reuse for irrigation on the agricultural environment: The knowns and unknowns of the fate of antibiotics and antibiotic resistant bacteria and resistance genes - A review.

    Science.gov (United States)

    Christou, Anastasis; Agüera, Ana; Bayona, Josep Maria; Cytryn, Eddie; Fotopoulos, Vasileios; Lambropoulou, Dimitra; Manaia, Célia M; Michael, Costas; Revitt, Mike; Schröder, Peter; Fatta-Kassinos, Despo

    2017-10-15

    The use of reclaimed wastewater (RWW) for the irrigation of crops may result in the continuous exposure of the agricultural environment to antibiotics, antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). In recent years, certain evidence indicate that antibiotics and resistance genes may become disseminated in agricultural soils as a result of the amendment with manure and biosolids and irrigation with RWW. Antibiotic residues and other contaminants may undergo sorption/desorption and transformation processes (both biotic and abiotic), and have the potential to affect the soil microbiota. Antibiotics found in the soil pore water (bioavailable fraction) as a result of RWW irrigation may be taken up by crop plants, bioaccumulate within plant tissues and subsequently enter the food webs; potentially resulting in detrimental public health implications. It can be also hypothesized that ARGs can spread among soil and plant-associated bacteria, a fact that may have serious human health implications. The majority of studies dealing with these environmental and social challenges related with the use of RWW for irrigation were conducted under laboratory or using, somehow, controlled conditions. This critical review discusses the state of the art on the fate of antibiotics, ARB and ARGs in agricultural environment where RWW is applied for irrigation. The implications associated with the uptake of antibiotics by plants (uptake mechanisms) and the potential risks to public health are highlighted. Additionally, knowledge gaps as well as challenges and opportunities are addressed, with the aim of boosting future research towards an enhanced understanding of the fate and implications of these contaminants of emerging concern in the agricultural environment. These are key issues in a world where the increasing water scarcity and the continuous appeal of circular economy demand answers for a long-term safe use of RWW for irrigation. Copyright © 2017 Elsevier

  19. VRprofile: gene-cluster-detection-based profiling of virulence and antibiotic resistance traits encoded within genome sequences of pathogenic bacteria.

    Science.gov (United States)

    Li, Jun; Tai, Cui; Deng, Zixin; Zhong, Weihong; He, Yongqun; Ou, Hong-Yu

    2017-01-10

    VRprofile is a Web server that facilitates rapid investigation of virulence and antibiotic resistance genes, as well as extends these trait transfer-related genetic contexts, in newly sequenced pathogenic bacterial genomes. The used backend database MobilomeDB was firstly built on sets of known gene cluster loci of bacterial type III/IV/VI/VII secretion systems and mobile genetic elements, including integrative and conjugative elements, prophages, class I integrons, IS elements and pathogenicity/antibiotic resistance islands. VRprofile is thus able to co-localize the homologs of these conserved gene clusters using HMMer or BLASTp searches. With the integration of the homologous gene cluster search module with a sequence composition module, VRprofile has exhibited better performance for island-like region predictions than the other widely used methods. In addition, VRprofile also provides an integrated Web interface for aligning and visualizing identified gene clusters with MobilomeDB-archived gene clusters, or a variety set of bacterial genomes. VRprofile might contribute to meet the increasing demands of re-annotations of bacterial variable regions, and aid in the real-time definitions of disease-relevant gene clusters in pathogenic bacteria of interest. VRprofile is freely available at http://bioinfo-mml.sjtu.edu.cn/VRprofile. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Selection of antibiotic resistance at very low antibiotic concentrations.

    Science.gov (United States)

    Sandegren, Linus

    2014-05-01

    Human use of antibiotics has driven the selective enrichment of pathogenic bacteria resistant to clinically used drugs. Traditionally, the selection of resistance has been considered to occur mainly at high, therapeutic levels of antibiotics, but we are now beginning to understand better the importance of selection of resistance at low levels of antibiotics. The concentration of an antibiotic varies in different body compartments during treatment, and low concentrations of antibiotics are found in sewage water, soils, and many water environments due to natural production and contamination from human activities. Selection of resistance at non-lethal antibiotic concentrations (below the wild-type minimum inhibitory concentration) occurs due to differences in growth rate at the particular antibiotic concentration between cells with different tolerance levels to the antibiotic. The minimum selective concentration for a particular antibiotic is reached when its reducing effect on growth of the susceptible strain balances the reducing effect (fitness cost) of the resistance determinant in the resistant strain. Recent studies have shown that resistant bacteria can be selected at concentrations several hundred-fold below the lethal concentrations for susceptible cells. Resistant mutants selected at low antibiotic concentrations are generally more fit than those selected at high concentrations but can still be highly resistant. The characteristics of selection at low antibiotic concentrations, the potential clinical problems of this mode of selection, and potential solutions will be discussed.

  1. Feasibility of sulfate-calcined eggshells for removing pathogenic bacteria and antibiotic resistance genes from landfill leachates.

    Science.gov (United States)

    Ye, Mao; Sun, Mingming; Chen, Xu; Feng, Yanfang; Wan, Jinzhong; Liu, Kuan; Tian, Da; Liu, Manqiang; Wu, Jun; Schwab, Arthur P; Jiang, Xin

    2017-05-01

    High abundance of human pathogen and antibiotic resistance genes (ARGs) in landfill leachate has become an emerging threat against human health. Therefore, sulfate- and calcination-modified eggshells as green agricultural bioresource were applied to test the feasibility of removing pathogenic bacteria and ARGs from leachate. The highest removal of Escherichia coli (E. coil) and gentamycin resistant gene (gmrA) from artificial contaminated landfill leachate was achieved by the application of eggshell with combined treatment of sulfate and calcination. The 16S and gmrA gene copies of E. coil declined significantly from 1.78E8±8.7E6 and 4.12E8±5.9E6 copies mL -1 to 1.32E7±2.6E6 and 2.69E7±7.2E6 copies mL -1 , respectively, within 24h dynamic adsorption equilibrium process (ppathogenic bacteria and ARGs (tet, sul, erm, qnr, and ampC) indicated its great efficiency to purify landfill leachates. This study demonstrated that sulfate-calcined eggshells can be an environmentally-friendly and highly efficient bioadsorbent to the management of reducing dissemination risk of pathogen and ARGs in landfill leachate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Therapeutic Potential of a Scorpion Venom-Derived Antimicrobial Peptide and Its Homologs Against Antibiotic-Resistant Gram-Positive Bacteria

    Directory of Open Access Journals (Sweden)

    Gaomin Liu

    2018-05-01

    Full Text Available The alarming rise in the prevalence of antibiotic resistance among pathogenic bacteria poses a unique challenge for the development of effective therapeutic agents. Antimicrobial peptides (AMPs have attracted a great deal of attention as a possible solution to the increasing problem of antibiotic-resistant bacteria. Marcin-18 was identified from the scorpion Mesobuthus martensii at both DNA and protein levels. The genomic sequence revealed that the marcin-18 coding gene contains a phase-I intron with a GT-AG splice junction located in the DNA region encoding the N-terminal part of signal peptide. The peptide marcin-18 was also isolated from scorpion venom. A protein sequence homology search revealed that marcin-18 shares extremely high sequence identity to the AMPs meucin-18 and megicin-18. In vitro, chemically synthetic marcin-18 and its homologs (meucin-18 and megicin-18 showed highly potent inhibitory activity against Gram-positive bacteria, including some clinical antibiotic-resistant strains. Importantly, in a mouse acute peritonitis model, these peptides significantly decreased the bacterial load in ascites and rescued nearly all mice heavily infected with clinical methicillin-resistant Staphylococcus aureus from lethal bacteremia. Peptides exerted antimicrobial activity via a bactericidal mechanism and killed bacteria through membrane disruption. Taken together, marcin-18 and its homologs have potential for development as therapeutic agents for treating antibiotic-resistant, Gram-positive bacterial infections.

  3. Designation of pathogenic resistant bacteria in the Sparusaurata sea collected in Tunisia coastlines: Correlation with high performance liquid chromatography-tandem mass spectrometry analysis of antibiotics.

    Science.gov (United States)

    Zouiten, Amina; Mehri, Ines; Beltifa, Asma; Ghorbel, Asma; Sire, Olivier; Van Loco, Joris; Abdenaceur, Hassen; Reyns, Tim; Ben Mansour, Hedi

    2017-05-01

    Vibrio is characterized by a large number of species and some of them are human pathogens causing gastro intestinal and wound infections through the ingestion or manipulation of contaminated fishes including Vibrio parahaemolyticus and Vibrio alginolyticus. In this study, we reported the phenotypic and molecular characterization of Vibrio parahaemolyticus and Vibrio alginolyticus strains isolated from wild and farm sea bream (Sparus aurata L.) along the Tunisian coast from December 2015 to April 2016. Therefore, the antibiograms indicate a difference between farmed and wild fish. Resistance against amoxicillin antibiotic appears for the bacteria isolated from wild fish, while those from aquaculture farming presented sensitivity to amoxicillin and resistance to antibiotics colistin and fusidic acid. The chloramphenicol antibiotic exhibited a high sensitivity in all isolated bacteria. In fact, traces of amoxicillin in the organs of the fish from Hergla farm were detected by UPLC-MS/MS analysis during December 2016 to April 2016. In addition, antibiotics were detected in January 2014 with high concentration of norfloxacin 2262 ng/g in fish from Hergla coast. The results obtained in this work indicated that the use and presence of antibiotics in water impacts on the occurrence of resistant bacteria and the detection of antibiotic in fish. Copyright © 2017. Published by Elsevier Ltd.

  4. Decellularized human amniotic membrane: more is needed for an efficient dressing for protection of burns against antibiotic-resistant bacteria isolated from burn patients.

    Science.gov (United States)

    Gholipourmalekabadi, M; Bandehpour, M; Mozafari, M; Hashemi, A; Ghanbarian, H; Sameni, M; Salimi, M; Gholami, M; Samadikuchaksaraei, A

    2015-11-01

    Human amniotic membranes (HAMs) have attracted the attention of burn surgeons for decades due to favorable properties such as their antibacterial activity and promising support of cell proliferation. On the other hand, as a major implication in the health of burn patients, the prevalence of bacteria resistant to multiple antibiotics is increasing due to overuse of antibiotics. The aim of this study was to investigate whether HAMs (both fresh and acellular) are an effective antibacterial agent against antibiotic-resistant bacteria isolated from burn patients. Therefore, a HAM was decellularized and tested for its antibacterial activity. Decellularization of the tissue was confirmed by hematoxylin and eosin (H&E) and 4,6-diamidino-2-phenylindole (DAPI) staining. In addition, the cyto-biocompatibility of the acellular HAM was proven by the cell viability test (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide, MTT) and scanning electron microscopy (SEM). The resistant bacteria were isolated from burns, identified, and tested for their susceptibility to antibiotics using both the antibiogram and polymerase chain reaction (PCR) techniques. Among the isolated bacteria, three blaIMP gene-positive Pseudomonas aeruginosa strains were chosen for their high resistance to the tested antibiotics. The antibacterial activity of the HAM was also tested for Klebsiella pneumoniae (American Type Culture Collection (ATCC) 700603) as a resistant ATCC bacterium; Staphylococcus aureus (mecA positive); and three standard strains of ATCC bacteria including Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27833), and S. aureus (ATCC 25923). Antibacterial assay revealed that only the latter three bacteria were susceptible to the HAM. All the data obtained from this study suggest that an alternative strategy is required to complement HAM grafting in order to fully protect burns from nosocomial infections. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

  5. Antimicrobial properties of black grape (Vitis vinifera L.) peel extracts against antibiotic-resistant pathogenic bacteria and toxin producing molds.

    Science.gov (United States)

    Yadav, Devbrat; Kumar, Arvind; Kumar, Pramod; Mishra, Diwaker

    2015-01-01

    Black grape peel possesses a substantial amount of polyphenolic antimicrobial compounds that can be used for controlling the growth of pathogenic microorganisms. The purpose of this study was to assess antibacterial and antifungal activity of black grape peel extracts against antibiotic-resistant pathogenic bacteria and toxin producing molds, respectively. Peel of grape was subjected to polyphenolic extraction using different solvents viz., water, ethanol, acetone, and methanol. Antibiotic-resistant strains of Staphylococcus aureus, Enterococcus faecalis, Enterobacter aerogenes, Salmonella typhimurium, and Escherichia coli were screened for the antibacterial activity of different grape extracts. Antibacterial activity was analyzed using agar well diffusion method. Penicillium chrysogenum, Penicillium expansum, Aspergillus niger and Aspergillus versicolor were screened for the antifungal activity. Antifungal activity was determined by counting nongerminated spores in the presence of peel extracts. As compared to other solvent extracts, methanol extracts possessed high antibacterial and antifungal activity. S. typhimurium and E. coli showed complete resistance against antibacterial action at screened concentrations of grape peel extracts. Maximum zone of inhibition was found in case of S. aureus, i.e., 22 mm followed by E. faecalis and E. aerogenes, i.e., 18 and 21 mm, respectively, at 1080 mg tannic acid equivalent (TAE)/ml. The maximum and minimum percent of growth inhibition was shown by P. expansum and A. niger as 73% and 15% at 1080 TAE/ml concentration of grape peel extract, respectively. Except S. typhimurium and E. coli, growth of all bacterial and mold species were found to be significantly (P < 0.05) inhibited by all the solvent extracts.

  6. Bacterial biofilms and antibiotic resistance

    Directory of Open Access Journals (Sweden)

    Liliana Caldas-Arias

    2015-04-01

    Full Text Available Biofilms give to bacteria micro-environmental benefits; confers protection against antimicrobials. Bacteria have antibiotic resistance by conventional and unusual mechanisms leading to delayed wound healing, to increase recurrent chronic infections and nosocomial contamination of medical devices. Objective: This narrative review aims to introduce the characteristics of Bacteria-biofilms, antimicrobial resistance mechanisms and potential alternatives for prevention and control of its formation. Methods: Search strategy was performed on records: PubMed / Medline, Lilacs, Redalyc; with suppliers such as EBSCO and thesaurus MeSH and DeCS. Conclusions: Knowledge and research performance of biofilm bacteria are relevant in the search of technology for detection and measuring sensitivity to antibiotics. The identification of Bacterial-biofilms needs no-traditional microbiological diagnosis.

  7. Prevalence and Antibiotic Resistance of Gram-Negative Pathogenic Bacteria Species Isolated from Periplaneta americana and Blattella germanica in Varanasi, India.

    Directory of Open Access Journals (Sweden)

    D Leshan Wannigama

    2014-06-01

    Full Text Available Cockroaches are among the medically important pests found within the human habitations that cause serious public health problems. They may harbor a number of pathogenic bacteria on the external surface with antibiotic resistance. Hence, they are regarded as major microbial vectors. This study investigates the prevalence and antibiotic resistance of Gram-negative pathogenic bacteria species isolated from Periplaneta americana and Blattella germanica in Varanasi, India.Totally, 203 adult cockroaches were collected form 44 households and 52 food-handling establishments by trapping. Bacteriological examination of external surfaces of Pe. americana and Bl. germanica were carried out using standard method and antibiotics susceptibility profiles of the isolates were determined using Kirby-Bauer disc diffusion methods.Among the places, we found that 54% had cockroache infestation in households and 77% in food- handling establishments. There was no significant different between the overall bacteria load of the external surface in Pe. americana (64.04% and Bl. germanica (35.96%. However the predominant bacteria on cockroaches were Klebsiella pneumonia, Escherichia coli, Enterobacter aerogenes, and Pseudomonas aeruginosa. However, Kl. pneumoniae and Ps. aeruginosa were the most prevalent, drug-resistant strains were isolated from the cockroaches with 100% resistance to sulfamethoxazole/trimethoprim and ampicillin. For individual strains of bacteria, Escherichia coli was found to have multi-resistance to four antibiotic tested, Citrobacter freundii four, Enterobacter aerogenes and Proteus mirabilis to three.Cockroaches are uniformly distributed in domestic environment, which can be a possible vector for transmission of drug-resistant bacteria and food-borne diseases.

  8. Antibiotic resistance profile of bacteria isolated from raw milk samples of cattle and buffaloes

    Directory of Open Access Journals (Sweden)

    Tahlina Tanzin

    2016-03-01

    Conclusion: Two different species of bacteria i.e., S. aureus and E. coli are contaminating with milk samples. The pathogenic bacteria can be controlled effectively by using Ciprofloxacin and Levofloxacin in the case of mastitis in cattle and buffaloes in Bangladesh. [J Adv Vet Anim Res 2016; 3(1.000: 62-67

  9. Antibiotic resistance increases with local temperature

    Science.gov (United States)

    MacFadden, Derek R.; McGough, Sarah F.; Fisman, David; Santillana, Mauricio; Brownstein, John S.

    2018-06-01

    Bacteria that cause infections in humans can develop or acquire resistance to antibiotics commonly used against them1,2. Antimicrobial resistance (in bacteria and other microbes) causes significant morbidity worldwide, and some estimates indicate the attributable mortality could reach up to 10 million by 20502-4. Antibiotic resistance in bacteria is believed to develop largely under the selective pressure of antibiotic use; however, other factors may contribute to population level increases in antibiotic resistance1,2. We explored the role of climate (temperature) and additional factors on the distribution of antibiotic resistance across the United States, and here we show that increasing local temperature as well as population density are associated with increasing antibiotic resistance (percent resistant) in common pathogens. We found that an increase in temperature of 10 °C across regions was associated with an increases in antibiotic resistance of 4.2%, 2.2%, and 2.7% for the common pathogens Escherichia coli, Klebsiella pneumoniae and Staphylococcus aureus. The associations between temperature and antibiotic resistance in this ecological study are consistent across most classes of antibiotics and pathogens and may be strengthening over time. These findings suggest that current forecasts of the burden of antibiotic resistance could be significant underestimates in the face of a growing population and climate change4.

  10. The multifaceted roles of antibiotics and antibiotic resistance in nature

    Directory of Open Access Journals (Sweden)

    Saswati eSengupta

    2013-03-01

    Full Text Available Antibiotics are chemotherapeutic agents, which have been a very powerful tool in the clinical management of bacterial diseases since the 1940s. However, benefits offered by these magic bullets have been substantially lost in subsequent days following the widespread emergence and dissemination of antibiotic resistant strains. While it is obvious that excessive and imprudent use of antibiotics significantly contributes to the emergence of resistant strains, antibiotic-resistance is also observed in natural bacteria of remote places unlikely to be impacted by human intervention. Both antibiotic biosynthetic genes and resistance-conferring genes have been known to evolve billions of years ago, long before clinical use of antibiotics. Hence it appears that antibiotics and antibiotics resistance determinants have some other roles in nature, which often elude our attention because of overemphasis on the therapeutic importance of antibiotics and the crisis imposed by the antibiotic-resistance in pathogens. In the natural milieu, antibiotics are often found to be present in subinhibitory concentrations acting as signalling molecules supporting quorum sensing and biofilm formation. They also play an important role in the production of virulence factors and influence host-parasite interactions (e.g., phagocytosis, adherence to the target cell and so on. The evolutionary and ecological aspects of antibiotics and antibiotic-resistance in the naturally occurring microbial community are little understood. Therefore, the actual role of antibiotics in nature warrants in-depth investigations. Studies on such an intriguing behaviour of the microorganisms promise insight into the intricacies of the microbial physiology and are likely to provide some lead in controlling the emergence and subsequent dissemination of antibiotic resistance. This article highlights some of the recent findings on the role of antibiotics and genes that confer resistance to antibiotics in

  11. Antibiotic resistance in Burkholderia species.

    Science.gov (United States)

    Rhodes, Katherine A; Schweizer, Herbert P

    2016-09-01

    The genus Burkholderia comprises metabolically diverse and adaptable Gram-negative bacteria, which thrive in often adversarial environments. A few members of the genus are prominent opportunistic pathogens. These include Burkholderia mallei and Burkholderia pseudomallei of the B. pseudomallei complex, which cause glanders and melioidosis, respectively. Burkholderia cenocepacia, Burkholderia multivorans, and Burkholderia vietnamiensis belong to the Burkholderia cepacia complex and affect mostly cystic fibrosis patients. Infections caused by these bacteria are difficult to treat because of significant antibiotic resistance. The first line of defense against antimicrobials in Burkholderia species is the outer membrane penetration barrier. Most Burkholderia contain a modified lipopolysaccharide that causes intrinsic polymyxin resistance. Contributing to reduced drug penetration are restrictive porin proteins. Efflux pumps of the resistance nodulation cell division family are major players in Burkholderia multidrug resistance. Third and fourth generation β-lactam antibiotics are seminal for treatment of Burkholderia infections, but therapeutic efficacy is compromised by expression of several β-lactamases and ceftazidime target mutations. Altered DNA gyrase and dihydrofolate reductase targets cause fluoroquinolone and trimethoprim resistance, respectively. Although antibiotic resistance hampers therapy of Burkholderia infections, the characterization of resistance mechanisms lags behind other non-enteric Gram-negative pathogens, especially ESKAPE bacteria such as Acinetobacter baumannii, Klebsiella pneumoniae and Pseudomonas aeruginosa. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. UPLC-MS/MS analysis of antibiotics in pharmaceutical effluent in Tunisia: ecotoxicological impact and multi-resistant bacteria dissemination.

    Science.gov (United States)

    Tahrani, Leyla; Mehri, Ines; Reyns, Tim; Anthonissen, Roel; Verschaeve, Luc; Khalifa, Anis Bel Haj; Loco, Joris Van; Abdenaceur, Hassen; Mansour, Hedi Ben

    2018-05-01

    The UPLC MS/MS analysis showed the presence of the two antibiotics in the pharmaceutical industry discharges during 3 months; norfloxacin and spiramycin which were quantified with the mean concentrations of 226.7 and 84.2 ng mL -1 , respectively. Sixteen resistant isolates were obtained from the pharmaceutical effluent and identified by sequencing. These isolates belong to different genera, namely Citrobacter, Acinetobacter, Pseudomonas, Delftia, Shewanella, and Rheinheimera. The antibiotic resistance phenotypes of these isolates were determined (27 tested antibiotics-discs). All the studied isolates were found resistant to amoxicillin and gentamicin, and 83.33% of isolates were resistant to ciprofloxacin. Multiple antibiotic resistances were revealed against β-lactams, quinolones, and aminoglycosides families. Our overall results suggest that the obtained bacterial isolates may constitute potential candidates for bioremediation and can be useful for biotechnological applications. Genotoxic effects were assessed by a battery of biotests; the pharmaceutical wastewater was genotoxic according to the bacterial Vitotox test and micronuclei test. Genotoxicity was also evaluated by the comet test; the tail DNA damages reached 38 and 22% for concentrated sample (10×) and non-concentrated sample (1×), respectively. However, the histological sections of kidney and liver's mice treated by pharmaceutical effluent showed normal histology and no visible structural effects or alterations as cytolysis, edema, or ulcerative necrosis were observed. Residual antibiotics can reach water environment through wastewater and provoke dissemination of the antibiotics resistance and induce genotoxic effects.

  13. Identification of 8-methyladenosine as the modification catalyzed by the radical SAM methyltransferase Cfr that confers antibiotic resistance in bacteria

    DEFF Research Database (Denmark)

    Giessing, Anders; Jensen, Søren Skov; Rasmussen, Anette

    2009-01-01

    The Cfr methyltransferase confers combined resistance to five different classes of antibiotics that bind to the peptidyl transferase center of bacterial ribosomes. The Cfr-mediated modification has previously been shown to occur on nucleotide A2503 of 23S rRNA and has a mass corresponding......,8-dimethyladenosine. The mutation of single conserved cysteine residues in the radical SAM motif CxxxCxxC of Cfr abolishes its activity, lending support to the notion that the Cfr modification reaction occurs via a radical-based mechanism. Antibiotic susceptibility data confirm that the antibiotic resistance...

  14. Prevalence of β-lactamase genes in domestic washing machines and dishwashers and the impact of laundering processes on antibiotic-resistant bacteria.

    Science.gov (United States)

    Rehberg, L; Frontzek, A; Melhus, Å; Bockmühl, D P

    2017-12-01

    To investigate the prevalence of β-lactamase genes in domestic washing machines and dishwashers, and the decontamination efficacy of laundering. For the first investigation, swab samples from washing machines (n = 29) and dishwashers (n = 24) were analysed by real-time quantitative PCR to detect genes encoding β-lactamases. To test the impact of laundering on resistant bacteria, cotton test swatches were artificially contaminated with susceptible and resistant strains of Pseudomonas aeruginosa, Klebsiella pneumoniae and Staphylococcus aureus within a second investigation. They were washed in a domestic washing machine with or without activated oxygen bleach (AOB)-containing detergent at 20-50°C. β-Lactamase genes (most commonly of the AmpC- and OXA-type) were detected in 79% of the washing machines and in 96% of the dishwashers and Pseudomonadaceae dominated the microbiota. The level of bacterial reduction after laundering was ≥80% for all Ps. aeruginosa and Kl. pneumoniae strains, while it was only 37-61% for the methicillin-resistant Staph. aureus outbreak strain. In general, the reduction was tendentially higher for susceptible bacteria than for the resistant outbreak strains, especially for Staph. aureus. β-Lactamase genes seem to be frequently present in domestic appliances and may pose a potential risk for cross-contamination and horizontal transfer of genes encoding resistance against clinically important β-lactams. In general, higher temperatures and the use of AOB can improve the reduction of antibiotic-resistant bacteria, including Staph. aureus which appears to be less susceptible to the decontamination effect of laundering. Data on the presence of antibiotic-resistant bacteria in the domestic environment are limited. This study suggests that β-lactamase genes in washing machines and dishwashers are frequent, and that antibiotic-resistant strains are generally more resistant to the used washing conditions. © 2017 The Society for

  15. Preliminary survey of antibiotic-resistant fecal indicator bacteria and pathogenic Escherichia coli from river-water samples collected in Oakland County, Michigan, 2003

    Science.gov (United States)

    Fogarty, Lisa R.; Duris, Joseph W.; Aichele, Stephen S.

    2005-01-01

    A preliminary study was done in Oakland County, Michigan, to determine the concentration of fecal indicator bacteria (fecal coliform bacteria and enterococci), antibiotic resistance patterns of these two groups, and the presence of potentially pathogenic Escherichia coli (E. coli). For selected sites, specific members of these groups [E. coli, Enterococcus faecium (E. faecium) and Enterococcus faecalis (E. faecalis)] were isolated and tested for levels of resistance to specific antibiotics used to treat human infections by pathogens in these groups and for their potential to transfer these resistances. In addition, water samples from all sites were tested for indicators of potentially pathogenic E. coli by three assays: a growth-based assay for sorbitol-negative E. coli, an immunological assay for E. coli O157, and a molecular assay for three virulence and two serotype genes. Samples were also collected from two non-urbanized sites outside of Oakland County. Results from the urbanized Oakland County area were compared to those from these two non-urbanized sites. Fecal indicator bacteria concentrations exceeded State of Michigan recreational water-quality standards and (or) recommended U.S. Environmental Protection Agency (USEPA) standards in samples from all but two Oakland County sites. Multiple-antibiotic-resistant fecal coliform bacteria were found at all sites, including two reference sites from outside the county. Two sites (Stony Creek and Paint Creek) yielded fecal coliform isolates resistant to all tested antibiotics. Patterns indicative of extended-spectrum-β-lactamase (ESBL)- producing fecal coliform bacteria were found at eight sites in Oakland County and E. coli resistant to clinically significant antibiotics were recovered from the River Rouge, Clinton River, and Paint Creek. Vancomycin-resistant presumptive enterococci were found at six sites in Oakland County and were not found at the reference sites. Evidence of acquired antibiotic resistances was

  16. Antibiotic-Resistant Gonorrhea

    Science.gov (United States)

    ... Search Form Controls Cancel Submit Search the CDC Gonorrhea Note: Javascript is disabled or is not supported ... on Facebook Sexually Transmitted Diseases (STDs) Antibiotic-Resistant Gonorrhea Recommend on Facebook Tweet Share Compartir Low Resolution ...

  17. tration on Phenotypic Antibiotic Susceptibility and Resistance

    African Journals Online (AJOL)

    resistance in bacteria of food animal origin (Van den Bogaard and Stobberingh, ... however, the effect of antimicrobial drug use in companion animals like dogs or ...... Antibiotic sensitivity of bacterial isolates from cases of canine dermatitis.

  18. Co-selection of antibiotic resistance via copper shock loading on bacteria from a drinking water bio-filter.

    Science.gov (United States)

    Zhang, Menglu; Chen, Lihua; Ye, Chengsong; Yu, Xin

    2018-02-01

    Heavy metal contamination of source water frequently occurred in developing countries as a result of accidents. To address the problems, most of the previous studies have focused on engineering countermeasures. In this study, we investigated the effects of heavy metals, particularly copper, on the development of antibiotic resistance by establishing a copper shock loading test. Results revealed that co-selection occurred rapidly within 6 h. Copper, at the levels of 10 and 100 mg/L, significantly increased bacterial resistance to the antibiotics tested, including rifampin, erythromycin, kanamycin, and a few others. A total of 117 antimicrobial-resistance genes were detected from 12 types of genes, and the relative abundance of most genes (particularly mobile genetic elements intⅠand transposons) was markedly enriched by at least one fold. Furthermore, the copper shock loading altered the bacterial community. Numerous heavy metal and antibiotic resistant strains were screened out and enriched. These strains are expected to enhance the overall level of resistance. More noticeably, the majority of the co-selected antibiotic resistance could sustain for at least 20 h in the absence of copper and antimicrobial drugs. Resistance to vancomycin, erythromycin and lincomycin even could remain for 7 days. The prominent selection pressure by the copper shock loading implies that a real accident most likely poses similar impacts on the water environment. An accidental release of heavy metals would not only cause harm to the ecological environment, but also contribute to the development of bacterial antibiotic resistance. Broader concerns should be raised about the biological risks caused by sudden releases of pollutants by accidents. Copyright © 2017. Published by Elsevier Ltd.

  19. Environmental pollution by antibiotics and by antibiotic resistance determinants

    International Nuclear Information System (INIS)

    Martinez, Jose Luis

    2009-01-01

    Antibiotics are among the most successful drugs used for human therapy. However, since they can challenge microbial populations, they must be considered as important pollutants as well. Besides being used for human therapy, antibiotics are extensively used for animal farming and for agricultural purposes. Residues from human environments and from farms may contain antibiotics and antibiotic resistance genes that can contaminate natural environments. The clearest consequence of antibiotic release in natural environments is the selection of resistant bacteria. The same resistance genes found at clinical settings are currently disseminated among pristine ecosystems without any record of antibiotic contamination. Nevertheless, the effect of antibiotics on the biosphere is wider than this and can impact the structure and activity of environmental microbiota. Along the article, we review the impact that pollution by antibiotics or by antibiotic resistance genes may have for both human health and for the evolution of environmental microbial populations. - The article reviews the current knowledge on the effects that pollution by antibiotics and antibiotic resistance genes may have for the microbiosphere.

  20. Environmental pollution by antibiotics and by antibiotic resistance determinants

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Jose Luis, E-mail: jlmtnez@cnb.csic.e [Departamento de Biotecnologia Microbiana, Centro Nacional de Biotecnologia, Consejo Superior de Investigaciones Cientificas, Darwin 3, Cantoblanco, 28049 Madrid, and CIBERESP (Spain)

    2009-11-15

    Antibiotics are among the most successful drugs used for human therapy. However, since they can challenge microbial populations, they must be considered as important pollutants as well. Besides being used for human therapy, antibiotics are extensively used for animal farming and for agricultural purposes. Residues from human environments and from farms may contain antibiotics and antibiotic resistance genes that can contaminate natural environments. The clearest consequence of antibiotic release in natural environments is the selection of resistant bacteria. The same resistance genes found at clinical settings are currently disseminated among pristine ecosystems without any record of antibiotic contamination. Nevertheless, the effect of antibiotics on the biosphere is wider than this and can impact the structure and activity of environmental microbiota. Along the article, we review the impact that pollution by antibiotics or by antibiotic resistance genes may have for both human health and for the evolution of environmental microbial populations. - The article reviews the current knowledge on the effects that pollution by antibiotics and antibiotic resistance genes may have for the microbiosphere.

  1. Antibiotic resistance in Salmonella

    NARCIS (Netherlands)

    Vo, A.T.T.

    2007-01-01

    Immediately after their introduction in the beginning of the fourties of the previous century, the agents used to combat infectious diseases caused by bacteria were regarded with suspicion, but not long thereafter antibiotics had the status of miracle drugs. For decades mankind has lived under the

  2. Antibiotic resistance monitoring: the Spanish programme. The VAV Network. Red de Vigilancia de Resistencias Antibióticas en Bacterias de Origen Veterinario.

    Science.gov (United States)

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

    2000-05-01

    Antimicrobial resistance is a problem in modern public health and antimicrobial use and especially misuse, the most important selecting force for bacterial antibiotic resistance. As this resistance must be monitored we have designed the Spanish network 'Red de Vigilancia de Resistencias Antibióticas en Bacterias de Origen Veterinario'. This network covers the three critical points of veterinary responsibility, bacteria from sick animals, bacteria from healthy animals and bacteria from food animals. Key bacteria, antimicrobials and animal species have been defined for each of these groups along with laboratory methods for testing antimicrobial susceptibility and for data analysis and reporting. Surveillance of sick animals was first implemented using Escherichia coli as the sentinel bacterium. Surveillance of E. coli and Enterococcus faecium from healthy pigs was implemented in 1998. In July 1999, data collection on Salmonella spp. was initiated in poultry slaughterhouses. Additionally, the prevalence of vancomycin resistant E. faecium was also monitored. This network has specific topics of interest related to methods of determining resistance, analysis and reporting of data, methods of use for veterinary practitioners and collaboration with public health authorities.

  3. Removal of micropollutants, facultative pathogenic and antibiotic resistant bacteria in a full-scale retention soil filter receiving combined sewer overflow.

    Science.gov (United States)

    Scheurer, Marco; Heß, Stefanie; Lüddeke, Frauke; Sacher, Frank; Güde, Hans; Löffler, Herbert; Gallert, Claudia

    2015-01-01

    Combined sewer systems collect surface runoff as well as wastewater of industrial and domestic origin. During periods of heavy rainfall the capacity of the sewer system is exceeded and the overflow is discharged into receiving waters without any treatment. Consequently, combined sewer overflow (CSO) is considered as a major source of water pollution. This study investigates the effectiveness of a retention soil filter (RSF) for the removal of micropollutants as well as facultative pathogenic and antibiotic resistant bacteria from CSO. The removal of organic group parameters like total organic carbon was excellent and the removal efficiency for micropollutants of the RSF and the wastewater treatment plant (WWTP), which treats wastewater of the same origin during dry and normal weather conditions, was comparable. Compounds of high environmental concern like estrogens or certain pharmaceuticals, e.g. diclofenac, were completely eliminated or removed to a high degree during RSF passage. RSF treatment also reduced the number of E. coli, enterococci and staphylococci by 2.7, 2.2 and 2.4 log-units (median values), respectively. Obviously, some Staphylococcus species can better adapt to the conditions of the RSF than others as a shift of the abundance of the different species was observed when comparing the diversity of staphylococci obtained from the RSF influent and effluent. RSF treatment also decreased the absolute number of antibiotic resistant bacteria. The percentage of antibiotic resistant E. coli and staphylococci isolates also decreased during passage of the RSF, whereas the percentage of resistant enterococci did not change. For E. coli ampicillin and for enterococci and staphylococci erythromycin determined the antibiotic resistance level. The results demonstrate that RSFs can be considered as an adequate treatment option for CSO. The performance for the removal of micropollutants is comparable with a medium sized WWTP with conventional activated sludge

  4. [Antibiotic resistance: A global crisis].

    Science.gov (United States)

    Alós, Juan-Ignacio

    2015-12-01

    The introduction of antibiotics into clinical practice represented one of the most important interventions for the control of infectious diseases. Antibiotics have saved millions of lives and have also brought a revolution in medicine. However, an increasing threat has deteriorated the effectiveness of these drugs, that of bacterial resistance to antibiotics, which is defined here as the ability of bacteria to survive in antibiotic concentrations that inhibit/kill others of the same species. In this review some recent and important examples of resistance in pathogens of concern for mankind are mentioned. It is explained, according to present knowledge, the process that led to the current situation in a short time, evolutionarily speaking. It begins with the resistance genes, continues with clones and genetic elements involved in the maintenance and dissemination, and ends with other factors that contribute to its spread. Possible responses to the problem are also reviewed, with special reference to the development of new antibiotics. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  5. Antibiotic Resistance in Foodborne Pathogens

    OpenAIRE

    Walsh, Ciara; Duffy, Geraldine

    2013-01-01

    Wide-spread antibiotic resistance among bacterial pathogens is now a serious public health issue and multi-antibiotic resistance has been reported in many foodborne pathogens including Salmonella and E. coli. A study to determine antibiotic resistance profiles of a range of Salmonella and Verocytotoxigenic E.coli (VTEC) isolated from Irish foods revealed significant levels of antibiotic resistance in the strains. S. typhimurium DT104 were multiantibiotic resistant with 97% resistant to 7 anti...

  6. Prevalence and persistence of potentially pathogenic and antibiotic resistant bacteria during anaerobic digestion treatment of cattle manure.

    Science.gov (United States)

    Resende, Juliana Alves; Silva, Vânia Lúcia; de Oliveira, Tamara Lopes Rocha; de Oliveira Fortunato, Samuel; da Costa Carneiro, Jailton; Otenio, Marcelo Henrique; Diniz, Cláudio Galuppo

    2014-02-01

    Anaerobic digestion figures as a sustainable alternative to avoid discharge of cattle manure in the environment, which results in biogas and biofertilizer. Persistence of potentially pathogenic and drug-resistant bacteria during anaerobic digestion of cattle manure was evaluated. Selective cultures were performed for enterobacteria (ENT), non-fermenting Gram-negative rods (NFR) and Gram-positive cocci (GPC). Antimicrobial susceptibility patterns were determined and a decay of all bacterial groups was observed after 60days. Multidrug-resistant bacteria were detected both the influent and effluent. GPC, the most prevalent group was highly resistant against penicillin and levofloxacin, whereas resistance to ampicillin, ampicillin-sulbactam and chloramphenicol was frequently observed in the ENT and NFR groups. The data point out the need of discussions to better address management of biodigesters and the implementation of sanitary and microbiological safe treatments of animal manures to avoid consequences to human, animal and environmental health. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Priorities for antibiotic resistance surveillance in Europe

    DEFF Research Database (Denmark)

    Fluit, A. C.; van der Bruggen, J. T.; Aarestrup, Frank Møller

    2006-01-01

    Antibiotic resistance is an increasing global problem. Surveillance studies are needed to monitor resistance development, to guide local empirical therapy, and to implement timely and adequate countermeasures. To achieve this, surveillance studies must have standardised methodologies, be longitud......Antibiotic resistance is an increasing global problem. Surveillance studies are needed to monitor resistance development, to guide local empirical therapy, and to implement timely and adequate countermeasures. To achieve this, surveillance studies must have standardised methodologies...... to the various reservoirs of antibiotic-resistant bacteria, such as hospitalised patients, nursing homes, the community, animals and food. Two studies that could serve as examples of tailored programmes are the European Antimicrobial Resistance Surveillance System (EARSS), which collects resistance data during...... of antibiotic resistance....

  8. Occurrence and distribution of multiple antibiotic-resistant bacteria of Enterobacteriaceae family in waters of Veraval coast, India

    Digital Repository Service at National Institute of Oceanography (India)

    Maloo, A.; Borade, S.; Dhawde, R.; Gajbhiye, S.N.; Dastager, S.G.

    ) bacteria is the overuse and misuse of antibiotics in human medicine, veterinary medicine, agriculture and aquaculture (McManus, Stockwell 2001). Microbial indicators have been used worldwide as a tool to indicate the contamination of water by human... the microbial contamination spread: station-1 (0 km from shore i.e. jetty area), station-2 (0.5 km inside to mouth harbor), station-3 (0.5 km outside to mouth harbor), station-4 (2 km right from station-3), station-5 (5 km left from station-3), station-6 (2...

  9. Addressing resistance to antibiotics in systematic reviews of antibiotic interventions.

    Science.gov (United States)

    Leibovici, Leonard; Paul, Mical; Garner, Paul; Sinclair, David J; Afshari, Arash; Pace, Nathan Leon; Cullum, Nicky; Williams, Hywel C; Smyth, Alan; Skoetz, Nicole; Del Mar, Chris; Schilder, Anne G M; Yahav, Dafna; Tovey, David

    2016-09-01

    Antibiotics are among the most important interventions in healthcare. Resistance of bacteria to antibiotics threatens the effectiveness of treatment. Systematic reviews of antibiotic treatments often do not address resistance to antibiotics even when data are available in the original studies. This omission creates a skewed view, which emphasizes short-term efficacy and ignores the long-term consequences to the patient and other people. We offer a framework for addressing antibiotic resistance in systematic reviews. We suggest that the data on background resistance in the original trials should be reported and taken into account when interpreting results. Data on emergence of resistance (whether in the body reservoirs or in the bacteria causing infection) are important outcomes. Emergence of resistance should be taken into account when interpreting the evidence on antibiotic treatment in randomized controlled trials or systematic reviews. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  10. Antimicrobial activity of Manuka honey against antibiotic-resistant strains of the cell wall-free bacteria Ureaplasma parvum and Ureaplasma urealyticum.

    Science.gov (United States)

    Hillitt, K L; Jenkins, R E; Spiller, O B; Beeton, M L

    2017-03-01

    The susceptibility of the cell wall-free bacterial pathogens Ureaplasma spp. to Manuka honey was examined. The minimum inhibitory concentration (MIC) of Manuka honey for four Ureaplasma urealyticum and four Ureaplasma parvum isolates was determined. Sensitivity to honey was also compared to clinical isolates with resistance to tetracycline, macrolide and fluoroquinolone antibiotics. Finally step-wise resistance training was utilized in an attempt to induce increased tolerance to honey. The MIC was dependent on the initial bacterial load with 7·5 and 18·0% w/v honey required to inhibit U. urealyticum at 1 and 10 6 colour changing units (CCU), respectively, and 4·8 and 15·3% w/v required to inhibit U. parvum at 1 and 10 6  CCU respectively. MIC values were consistently lower for U. parvum compared with U. urealyticum. Antimicrobial activity was seen against tetracycline-resistant, erythromycin-resistant and ciprofloxacin-resistant isolates at 10 5  CCU. No resistance to honey was observed with 50 consecutive challenges at increasing concentrations of honey. This is the first report of the antimicrobial activity of Manuka honey against a cell wall-free bacterial pathogen. The antimicrobial activity was retained against antibiotic-resistant strains and it was not possible to generate resistant mutants. Manuka honey is known to have a broad spectrum of antimicrobial activity, with the bacterial cell wall being suggested as a predominant site of action. This study has demonstrated that Manuka honey has activity against Ureaplasma spp., a genus of cell wall-free bacteria which are intrinsically resistant to many available antibiotics making treatment inherently difficult. This is the first report of the antimicrobial activity of Manuka honey against a bacterial pathogen, in the absence of a cell well and opens scope for the use of components of Manuka honey as a therapeutic among Ureaplasma infections. © 2016 The Society for Applied Microbiology.

  11. Antibiotic resistance in animals.

    Science.gov (United States)

    Barton, Mary D; Pratt, Rachael; Hart, Wendy S

    2003-01-01

    There is currently no systematic surveillance or monitoring of antibiotic resistance in Australian animals. Registration of antibiotics for use in animals is tightly controlled and has been very conservative. Fluoroquinolones have not been registered for use in food producing animals and other products have been removed from the market because of human health concerns. In the late 1970s, the Animal Health Committee coordinated a survey of resistance in Salmonella and Escherichia coli isolates from cattle, pigs and poultry and in bovine Staphylococcus aureus. Some additional information is available from published case reports. In samples collected prior to the withdrawal of avoparcin from the market, no vancomycin resistant Enterococcus faecium or Enterococcus faecalis were detected in samples collected from pigs, whereas some vanA enterococci, including E. faecium and E. faecalis, were found in chickens. No vanB enterococci were detected in either species. Virginiamycin resistance was common in both pig and poultry isolates. Multiple resistance was common in E. coli and salmonellae isolates. No fluoroquinolone resistance was found in salmonellae, E. coli or Campylobacter. Beta-lactamase production is common in isolates from bovine mastitis, but no methicillin resistance has been detected. However, methicillin resistance has been reported in canine isolates of Staphylococcus intermedius and extended spectrum beta-lactamase producing E. coli has been found in dogs.

  12. Strategies to Minimize Antibiotic Resistance

    Directory of Open Access Journals (Sweden)

    Sang Hee Lee

    2013-09-01

    Full Text Available Antibiotic resistance can be reduced by using antibiotics prudently based on guidelines of antimicrobial stewardship programs (ASPs and various data such as pharmacokinetic (PK and pharmacodynamic (PD properties of antibiotics, diagnostic testing, antimicrobial susceptibility testing (AST, clinical response, and effects on the microbiota, as well as by new antibiotic developments. The controlled use of antibiotics in food animals is another cornerstone among efforts to reduce antibiotic resistance. All major resistance-control strategies recommend education for patients, children (e.g., through schools and day care, the public, and relevant healthcare professionals (e.g., primary-care physicians, pharmacists, and medical students regarding unique features of bacterial infections and antibiotics, prudent antibiotic prescribing as a positive construct, and personal hygiene (e.g., handwashing. The problem of antibiotic resistance can be minimized only by concerted efforts of all members of society for ensuring the continued efficiency of antibiotics.

  13. Interventions on Metabolism: Making Antibiotic-Susceptible Bacteria

    Directory of Open Access Journals (Sweden)

    Fernando Baquero

    2017-11-01

    Full Text Available Antibiotics act on bacterial metabolism, and antibiotic resistance involves changes in this metabolism. Interventions on metabolism with drugs might therefore modify drug susceptibility and drug resistance. In their recent article, Martin Vestergaard et al. (mBio 8:e01114-17, 2017, https://doi.org/10.1128/mBio.01114-17 illustrate the possibility of converting intrinsically resistant bacteria into susceptible ones. They reported that inhibition of a central metabolic enzyme, ATP synthase, allows otherwise ineffective polymyxin antibiotics to act on Staphylococcus aureus. The study of the intrinsic resistome of bacterial pathogens has shown that several metabolic genes, including multigene transcriptional regulators, contribute to antibiotic resistance. In some cases, these genes only marginally increase antibiotic resistance, but reduced levels of susceptibility might be critical in the evolution or resistance under low antibiotic concentrations or in the clinical response of highly resistant bacteria. Drug interventions on bacterial metabolism might constitute a critical adjuvant therapy in combination with antibiotics to ensure susceptibility of pathogens with intrinsic or acquired antimicrobial resistance.

  14. Plant Growth, Antibiotic Uptake, and Prevalence of Antibiotic Resistance in an Endophytic System of Pakchoi under Antibiotic Exposure

    Directory of Open Access Journals (Sweden)

    Hao Zhang

    2017-11-01

    Full Text Available Antibiotic contamination in agroecosystems may cause serious problems, such as the proliferation of various antibiotic resistant bacteria and the spreading of antibiotic resistance genes (ARGs in the environment or even to human beings. However, it is unclear whether environmental antibiotics, antibiotic resistant bacteria, and ARGs can directly enter into, or occur in, the endophytic systems of plants exposed to pollutants. In this study, a hydroponic experiment exposing pakchoi (Brassica chinensis L. to tetracycline, cephalexin, and sulfamethoxazole at 50% minimum inhibitory concentration (MIC levels and MIC levels, respectively, was conducted to explore plant growth, antibiotic uptake, and the development of antibiotic resistance in endophytic systems. The three antibiotics promoted pakchoi growth at 50% MIC values. Target antibiotics at concentrations ranging from 6.9 to 48.1 µg·kg−1 were detected in the treated vegetables. Additionally, the rates of antibiotic-resistant endophytic bacteria to total cultivable endophytic bacteria significantly increased as the antibiotics accumulated in the plants. The detection and quantification of ARGs indicated that four types, tetX, blaCTX-M, and sul1 and sul2, which correspond to tetracycline, cephalexin, and sulfamethoxazole resistance, respectively, were present in the pakchoi endophytic system and increased with the antibiotic concentrations. The results highlight a potential risk of the development and spread of antibiotic resistance in vegetable endophytic systems.

  15. Plant Growth, Antibiotic Uptake, and Prevalence of Antibiotic Resistance in an Endophytic System of Pakchoi under Antibiotic Exposure.

    Science.gov (United States)

    Zhang, Hao; Li, Xunan; Yang, Qingxiang; Sun, Linlin; Yang, Xinxin; Zhou, Mingming; Deng, Rongzhen; Bi, Linqian

    2017-11-03

    Antibiotic contamination in agroecosystems may cause serious problems, such as the proliferation of various antibiotic resistant bacteria and the spreading of antibiotic resistance genes (ARGs) in the environment or even to human beings. However, it is unclear whether environmental antibiotics, antibiotic resistant bacteria, and ARGs can directly enter into, or occur in, the endophytic systems of plants exposed to pollutants. In this study, a hydroponic experiment exposing pakchoi ( Brassica chinensis L.) to tetracycline, cephalexin, and sulfamethoxazole at 50% minimum inhibitory concentration (MIC) levels and MIC levels, respectively, was conducted to explore plant growth, antibiotic uptake, and the development of antibiotic resistance in endophytic systems. The three antibiotics promoted pakchoi growth at 50% MIC values. Target antibiotics at concentrations ranging from 6.9 to 48.1 µg·kg -1 were detected in the treated vegetables. Additionally, the rates of antibiotic-resistant endophytic bacteria to total cultivable endophytic bacteria significantly increased as the antibiotics accumulated in the plants. The detection and quantification of ARGs indicated that four types, tet X, bla CTX-M , and sul 1 and sul 2, which correspond to tetracycline, cephalexin, and sulfamethoxazole resistance, respectively, were present in the pakchoi endophytic system and increased with the antibiotic concentrations. The results highlight a potential risk of the development and spread of antibiotic resistance in vegetable endophytic systems.

  16. Convergent acquisition of antibiotic resistance determinants ...

    African Journals Online (AJOL)

    Convergent acquisition of antibiotic resistance determinants amongst the Enterobacteriaceae isolates of the Mhlathuze River, KwaZulu-Natal (RSA) ... The possibility of transmission of resistant genes between bacteria (especially pathogenic) which invade human and animal populations within this river poses a health risk ...

  17. How to Fight Back Against Antibiotic Resistance

    DEFF Research Database (Denmark)

    Dantas, Gautam; Sommer, Morten

    2014-01-01

    compounds. To save the era of antibiotics, scientists must figure out what it is about bacterial pathogens that makes resistance inevitable. Although most studies on drug resistance have focused on disease causing pathogens, recent efforts have shifted attention to the resistomes of nonpathogenic bacteria...

  18. Dissemination of antibiotic resistance genes from antibiotic producers to pathogens

    DEFF Research Database (Denmark)

    Jiang, Xinglin; Ellabaan, Mostafa M Hashim; Charusanti, Pep

    2017-01-01

    It has been hypothesized that some antibiotic resistance genes (ARGs) found in pathogenic bacteria derive from antibiotic-producing actinobacteria. Here we provide bioinformatic and experimental evidence supporting this hypothesis. We identify genes in proteobacteria, including some pathogens...... and experimentally test a 'carry-back' mechanism for the transfer, involving conjugative transfer of a carrier sequence from proteobacteria to actinobacteria, recombination of the carrier sequence with the actinobacterial ARG, followed by natural transformation of proteobacteria with the carrier-sandwiched ARG. Our...... results support the existence of ancient and, possibly, recent transfers of ARGs from antibiotic-producing actinobacteria to proteobacteria, and provide evidence for a defined mechanism....

  19. Resistance of Bacteria to Biocides.

    Science.gov (United States)

    Maillard, Jean-Yves

    2018-04-01

    Biocides and formulated biocides are used worldwide for an increasing number of applications despite tightening regulations in Europe and in the United States. One concern is that such intense usage of biocides could lead to increased bacterial resistance to a product and cross-resistance to unrelated antimicrobials including chemotherapeutic antibiotics. Evidence to justify such a concern comes mostly from the use of health care-relevant bacterial isolates, although the number of studies of the resistance characteristics of veterinary isolates to biocides have increased the past few years. One problem remains the definition of "resistance" and how to measure resistance to a biocide. This has yet to be addressed globally, although the measurement of resistance is becoming more pressing, with regulators both in Europe and in the United States demanding that manufacturers provide evidence that their biocidal products will not impact on bacterial resistance. Alongside in vitro evidence of potential antimicrobial cross-resistance following biocide exposure, our understanding of the mechanisms of bacterial resistance and, more recently, our understanding of the effect of biocides to induce a mechanism(s) of resistance in bacteria has improved. This article aims to provide an understanding of the development of antimicrobial resistance in bacteria following a biocide exposure. The sections provide evidence of the occurrence of bacterial resistance and its mechanisms of action and debate how to measure bacterial resistance to biocides. Examples pertinent to the veterinary field are used where appropriate.

  20. Action and resistance mechanisms of antibiotics: A guide for clinicians

    Directory of Open Access Journals (Sweden)

    Garima Kapoor

    2017-01-01

    Full Text Available Infections account for a major cause of death throughout the developing world. This is mainly due to the emergence of newer infectious agents and more specifically due to the appearance of antimicrobial resistance. With time, the bacteria have become smarter and along with it, massive imprudent usage of antibiotics in clinical practice has resulted in resistance of bacteria to antimicrobial agents. The antimicrobial resistance is recognized as a major problem in the treatment of microbial infections. The biochemical resistance mechanisms used by bacteria include the following: antibiotic inactivation, target modification, altered permeability, and “bypass” of metabolic pathway. Determination of bacterial resistance to antibiotics of all classes (phenotypes and mutations that are responsible for bacterial resistance to antibiotics (genetic analysis are helpful. Better understanding of the mechanisms of antibiotic resistance will help clinicians regarding usage of antibiotics in different situations. This review discusses the mechanism of action and resistance development in commonly used antimicrobials.

  1. Photodynamic inactivation of antibiotic-resistant pathogens

    International Nuclear Information System (INIS)

    Paronyan, M.H.

    2015-01-01

    Nowadays methicillin-resistant strain Staphylococcus aureus (MRSA) is one of the most widespread multiresistant bacteria. Photodynamic inactivation (PDI) of microorganisms by photosensitizers (PS) may be an effective and alternative therapeutic option against antibiotic resistant bacteria. The effectiveness of new PS cationic porphyrin Zn-TBut4PyP was tested on two strains of S. aureus (MRSA and methicillin-sensitive S. aureus). It is shown that Zn-TBut4PyP has high photodynamic activity against both strains

  2. Bacterial Cheating Limits the Evolution of Antibiotic Resistance

    Science.gov (United States)

    Yurtsev, Eugene; Xiao Chao, Hui; Datta, Manoshi; Artemova, Tatiana; Gore, Jeff

    2012-02-01

    The emergence of antibiotic resistance in bacteria is a significant health concern. Bacteria can gain resistance to the antibiotic ampicillin by acquiring a plasmid carrying the gene beta-lactamase, which inactivates the antibiotic. This inactivation may represent a cooperative behavior, as the entire bacterial population benefits from removal of the antibiotic. The presence of a cooperative mechanism of resistance suggests that a cheater strain - which does not contribute to breaking down the antibiotic - may be able to take advantage of resistant cells. We find experimentally that a ``sensitive'' bacterial strain lacking the plasmid conferring resistance can invade a population of resistant bacteria, even in antibiotic concentrations that should kill the sensitive strain. We use a simple model in conjunction with difference equations to explain the observed population dynamics as a function of cell density and antibiotic concentration. Our experimental difference equations resemble the logistic map, raising the possibility of oscillations or even chaotic dynamics.

  3. Silver enhances antibiotic activity against gram-negative bacteria.

    Science.gov (United States)

    Morones-Ramirez, J Ruben; Winkler, Jonathan A; Spina, Catherine S; Collins, James J

    2013-06-19

    A declining pipeline of clinically useful antibiotics has made it imperative to develop more effective antimicrobial therapies, particularly against difficult-to-treat Gram-negative pathogens. Silver has been used as an antimicrobial since antiquity, yet its mechanism of action remains unclear. We show that silver disrupts multiple bacterial cellular processes, including disulfide bond formation, metabolism, and iron homeostasis. These changes lead to increased production of reactive oxygen species and increased membrane permeability of Gram-negative bacteria that can potentiate the activity of a broad range of antibiotics against Gram-negative bacteria in different metabolic states, as well as restore antibiotic susceptibility to a resistant bacterial strain. We show both in vitro and in a mouse model of urinary tract infection that the ability of silver to induce oxidative stress can be harnessed to potentiate antibiotic activity. Additionally, we demonstrate in vitro and in two different mouse models of peritonitis that silver sensitizes Gram-negative bacteria to the Gram-positive-specific antibiotic vancomycin, thereby expanding the antibacterial spectrum of this drug. Finally, we used silver and antibiotic combinations in vitro to eradicate bacterial persister cells, and show both in vitro and in a mouse biofilm infection model that silver can enhance antibacterial action against bacteria that produce biofilms. This work shows that silver can be used to enhance the action of existing antibiotics against Gram-negative bacteria, thus strengthening the antibiotic arsenal for fighting bacterial infections.

  4. Predation and selection for antibiotic resistance in natural environments

    DEFF Research Database (Denmark)

    Leisner, Jørgen; Jørgensen, Niels O. G.; Middelboe, Mathias

    2016-01-01

    Genes encoding resistance to antibiotics appear, like the antibiotics themselves, to be ancient, originating long before the rise of the era of anthropogenic antibiotics. However, detailed understanding of the specific biological advantages of antibiotic resistance in natural environments is still...... lacking, thus limiting our efforts to prevent environmental influx of resistance genes. Here, we propose that antibiotic-resistant cells not only evade predation from antibiotic producers but also take advantage of nutrients released from cells that are killed by the antibiotic-producing bacteria. Thus......, predation is potentially an important mechanism for driving antibiotic resistance during slow or stationary phase of growth when nutrients are deprived. This adds to explain the ancient nature and widespread occurrence of antibiotic resistance in natural environments unaffected by anthropogenic antibiotics...

  5. Addressing the Natural Antibiotic Resistome in Studies of Soil Resistance

    Science.gov (United States)

    The environment is recognized as a source and a reservoir of antibiotic resistance (AR). Many antibiotic compounds are derived from bacteria and fungi that are naturally present in the environment. These microbes carry genes encoding resistance to the antibiotic that they produce and their resistanc...

  6. Banning antibiotics, reducing resistance, preventing and fighting infections : White paper on research enabling an 'antibiotic-free' animal husbandry

    NARCIS (Netherlands)

    Kimman, T.G.; Smits, M.A.; Kemp, B.; Wever, P.; Verheijden, J.

    2010-01-01

    Resistance of bacteria to antibiotics in animal husbandry is increasing and a point of growing concern. The large use of antibiotics in agriculture undoubtedly leads to the development of antibiotic resistance. This has resulted in a growing public concern on the rise of antibiotic resistance, and

  7. Antibiotic Resistance and Antibiotic Resistance Genes in Escherichia coli Isolates from Hospital Wastewater in Vietnam.

    Science.gov (United States)

    Lien, La Thi Quynh; Lan, Pham Thi; Chuc, Nguyen Thi Kim; Hoa, Nguyen Quynh; Nhung, Pham Hong; Thoa, Nguyen Thi Minh; Diwan, Vishal; Tamhankar, Ashok J; Stålsby Lundborg, Cecilia

    2017-06-29

    The environmental spread of antibiotic-resistant bacteria has been recognised as a growing public health threat for which hospitals play a significant role. The aims of this study were to investigate the prevalence of antibiotic resistance and antibiotic resistance genes (ARGs) in Escherichia coli isolates from hospital wastewater in Vietnam. Wastewater samples before and after treatment were collected using continuous sampling every month over a year. Standard disk diffusion and E-test were used for antibiotic susceptibility testing. Extended-spectrum beta-lactamase (ESBL) production was tested using combined disk diffusion. ARGs were detected by polymerase chain reactions. Resistance to at least one antibiotic was detected in 83% of isolates; multidrug resistance was found in 32%. The highest resistance prevalence was found for co-trimoxazole (70%) and the lowest for imipenem (1%). Forty-three percent of isolates were ESBL-producing, with the bla TEM gene being more common than bla CTX-M . Co-harbouring of the bla CTX-M , bla TEM and qepA genes was found in 46% of isolates resistant to ciprofloxacin. The large presence of antibiotic-resistant E. coli isolates combined with ARGs in hospital wastewater, even post-treatment, poses a threat to public health. It highlights the need to develop effective processes for hospital wastewater treatment plants to eliminate antibiotic resistant bacteria and ARGs.

  8. Biodegradation of 2,4-dichlorophenoxyacetic acid by bacteria with highly antibiotic-resistant pattern isolated from wheat field soils in Kurdistan, Iran.

    Science.gov (United States)

    Karami, Solmaz; Maleki, Afshin; Karimi, Ebrahim; Poormazaheri, Helen; Zandi, Shiva; Davari, Behrooz; Salimi, Yahya Zand; Gharibi, Fardin; Kalantar, Enayatollah

    2016-12-01

    Recently, there has been increasing interest to clean up the soils contaminated with herbicide. Our aim was to determine the bioremediation of 2,4-dichlorophenoxyacetic acid (2,4-D) from wheat fields which have a long history of herbicide in Sanandaj. Based on our literature survey, this study is the first report to isolate and identify antimicrobial resistant bacteria from polluted wheat field soils in Sanandaj which has the capacity to degrade 2,4-D. From 150 2,4-D-exposed soil samples, five different bacteria were isolated and identified based on biochemical tests and 16S ribosomal RNA (rRNA). Pseudomonas has been the most frequently isolated genus. By sequencing the 16S rRNA gene of the isolated bacteria, the strains were detected and identified as a member of the genus Pseudomonas sp, Entrobacter sp, Bacillus sp, Seratia sp, and Staphylococcus sp. The sequence of Sanandaj 1 isolate displayed 87% similarity with the 16S rRNA gene of a Pseudomonas sp (HE995788). Similarly, all the isolates were compared to standard strains based on 16S rRNA. Small amounts of 2,4-D could be transmitted to a depth of 10-20 cm; however, in the depth of 20-40 cm, we could not detect the 2,4-D. The isolates were resistant to various antibiotics particularly, penicillin, ampicillin, and amoxicillin.

  9. Mechanisms of antibiotic resistance in Staphylococcus aureus.

    Science.gov (United States)

    Pantosti, Annalisa; Sanchini, Andrea; Monaco, Monica

    2007-06-01

    Staphylococcus aureus can exemplify better than any other human pathogen the adaptive evolution of bacteria in the antibiotic era, as it has demonstrated a unique ability to quickly respond to each new antibiotic with the development of a resistance mechanism, starting with penicillin and methicillin, until the most recent, linezolid and daptomycin. Resistance mechanisms include enzymatic inactivation of the antibiotic (penicillinase and aminoglycoside-modification enzymes), alteration of the target with decreased affinity for the antibiotic (notable examples being penicillin-binding protein 2a of methicillin-resistant S. aureus and D-Ala-D-Lac of peptidoglycan precursors of vancomycin-resistant strains), trapping of the antibiotic (for vancomycin and possibly daptomycin) and efflux pumps (fluoroquinolones and tetracycline). Complex genetic arrays (staphylococcal chromosomal cassette mec elements or the vanA operon) have been acquired by S. aureus through horizontal gene transfer, while resistance to other antibiotics, including some of the most recent ones (e.g., fluoroquinolones, linezolid and daptomycin) have developed through spontaneous mutations and positive selection. Detection of the resistance mechanisms and their genetic basis is an important support to antibiotic susceptibility surveillance in S. aureus.

  10. Plasmid mediated resistance in multidrug resistant bacteria isolated ...

    African Journals Online (AJOL)

    The antibiotic susceptibility testing of isolated bacteria associated with septicaemia in children were carried out using standard microbiological protocol. The MAR index for the test bacterial isolates was determined and the bacterial isolates that displayed multiple antibiotic resistance were investigated for the presence of ...

  11. The Prevalence of Antibiotic Resistant Diarrhogenic Bacterial ...

    African Journals Online (AJOL)

    GB

    2017-07-01

    Jul 1, 2017 ... Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the ..... (septic tank, diving), pets, and wild birds. Various species of bacteria were isolated, most of them ..... Vakulenko, S. An antibiotic resistance enzyme from a deep-sea bacterium.J. Am. Chem.

  12. H{sub 2}O{sub 2} and/or TiO{sub 2} photocatalysis under UV irradiation for the removal of antibiotic resistant bacteria and their antibiotic resistance genes

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Changsheng [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Wang, Kai [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Wuxi SensingNet Industrialization Research Institute, Wuxi 214000 (China); Hou, Song; Wan, Li; Lv, Jiapei; Zhang, Yuan [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Qu, Xiaodong [State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, and Department of Water Environment, China Institute of Water Resources and Hydropower Research, Beijing 100038 (China); Chen, Shuyi [Wuxi SensingNet Industrialization Research Institute, Wuxi 214000 (China); Xu, Jian, E-mail: xujian@craes.org.cn [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China)

    2017-02-05

    Highlights: • TiO{sub 2} thin film was successfully synthesized for treating ARB and ARGs from water. • More than 5.5 log units of ARB reduction was achieved by TiO{sub 2} under UV irradiation. • With TiO{sub 2}, ARGs were reduced by more than 5 log units under UV irradiation. • TiO{sub 2} could remove both intracellular and extracellular forms of ARGs. - Abstract: Inactivating antibiotic resistant bacteria (ARB) and removing antibiotic resistance genes (ARGs) are very important to prevent their spread into the environment. Previous efforts have been taken to eliminate ARB and ARGs from aqueous solution and sludges, however, few satisfying results have been obtained. This study investigated whether photocatalysis by TiO{sub 2} was able to reduce the two ARGs, mecA and ampC, within the host ARB, methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, respectively. The addition of H{sub 2}O{sub 2} and matrix effect on the removal of ARB and ARGs were also studied. TiO{sub 2} thin films showed great effect on both ARB inactivation and ARGs removal. Approximately 4.5-5.0 and 5.5–5.8 log ARB reductions were achieved by TiO{sub 2} under 6 and 12 mJ/cm{sup 2} UV{sub 254} fluence dose, respectively. For ARGs, 5.8 log mecA reduction and 4.7 log ampC reduction were achieved under 120 mJ/cm{sup 2} UV{sub 254} fluence dose in the presence of TiO{sub 2}. Increasing dosage of H{sub 2}O{sub 2} enhanced the removal efficiencies of ARB and ARGs. The results also demonstrated that photocatalysis by TiO{sub 2} was capable of removing both intracellular and extracellular forms of ARGs. This study provided a potential alternative method for the removal of ARB and ARGs from aqueous solution.

  13. Antibiotic resistance - the interplay between antibiotic use in animals and human beings

    DEFF Research Database (Denmark)

    Singer, R.S.; Finch, R.; Wegener, Henrik Caspar

    2003-01-01

    Antibiotic-resistant bacteria were first identified in the 1940s, but while new antibiotics were being discovered at a steady rate, the consequences of this phenomenon were slow to be appreciated. Today, the excessive use of antibiotics compounded by the paucity of new agents on the market has...... meant the problem of antibiotic resistance is fast escalating into a global health crisis. There is no doubt that misuse of these drugs in human beings has contributed to the increasing rates of resistance, but recently the use of antibiotics in food animals and its consequent effect on resistance....... There is a growing concern over the transmission of resistant bacteria via the food chain. Many questions will be difficult to resolve, such as how do you distinguish the fraction of resistance in human beings that originated from animals? If we wait to see evidence that a significant amount of antibiotic resistance...

  14. Antibiotic Resistance Patterns of Common Gram-negative ...

    African Journals Online (AJOL)

    Background: The resistance of bacteria causing urinary tract infection (UTI) to commonly prescribed antibiotics is increasing both in developing and developed countries. Resistance has emerged even to more potent antimicrobial agents. This study was undertaken to determine the current antibiotic resistance pattern ...

  15. Bactérias gram negativas resistentes a antimicrobianos em alimentos Gram-negative bacteria resistant to antibiotics in foods

    Directory of Open Access Journals (Sweden)

    José Cavalcante de Albuquerque Ribeiro Dias

    1985-12-01

    Full Text Available A partir de 154 espécimens de alimentos, representados por hortaliças (alface, leite e merenda escolar, obteve-se o isolamento e identificação de 400 amostras de bacilos Gram negativos. Esta amostragem se distribuiu em 339 enterobactérias (Escherichia, Shigella, Citrobacter, Klebsiella, Enterobacter, Serratia e Proteus e 61 de gêneros afins (Acinetobacter, Flavobacterium, Aeromonas e Pseudomonas. Submetendo-se as culturas aos antimicrobianos: sulfadiazina (Su, estreptomicina (Sm, tetraciclina (Tc, cloranfenicol (Cm, canamicina (Km, ampicilina (Ap, ácido nalidíxico (Nal e gentamicina (Gm, observou-se apenas seis estirpes sensíveis a todas as drogas e sensibilidade absoluta à Gm. A predominância dos modelos Su (27,6% e Su-Ap (39,6% incidiu nas enterobactérias, enquanto que, 18,0% para Ap e 9,8% para Su-Ap foram detectados nos gêneros afins. Para caracterização da resistência foram realizados testes de conjugação e a totalidade das culturas não revelou transferência para o gene que confere resistência ao ácido nalidíxico. Relevantes são as taxas de amostras R+ observadas nos bacilos entéricos, oscilando em torno de 90% (leite e merenda escolar e alface, em torno de 70%From 154 food samples, including vegetables (lettuce, milk and meals served at school it was possible to isolate and identify 400 Gram negative bacilli distributed among 339 enteric bacteria (Escherichia, Shigella, Citrobacter, Klebsiella, Enterobacter, Serratia and Proteus and other 61 non enteric bacilli (Acinetobacter, Flavobacterium, Aeromonas and Pseudomonas. Submitting this cultures to the drugs sulfadiazine (Su, streptomycin (Sm, tetracycline (Tc, chloramphenicol (Cm, kanamycin (Km, ampicillin (Ap, nalidixic acid (Nal and gentamycin (Gm it was observed only six stocks susceptible to all drugs and total sensibility to Gm. Among enteric bacteria the profiles Su (27,6% and Su-Ap (39,6% predominated, while for the non enteric bacilli percentages of 18.0 for

  16. Does antifouling paint select for antibiotic resistance?

    Science.gov (United States)

    Flach, Carl-Fredrik; Pal, Chandan; Svensson, Carl Johan; Kristiansson, Erik; Östman, Marcus; Bengtsson-Palme, Johan; Tysklind, Mats; Larsson, D G Joakim

    2017-07-15

    There is concern that heavy metals and biocides contribute to the development of antibiotic resistance via co-selection. Most antifouling paints contain high amounts of such substances, which risks turning painted ship hulls into highly mobile refuges and breeding grounds for antibiotic-resistant bacteria. The objectives of this study were to start investigate if heavy-metal based antifouling paints can pose a risk for co-selection of antibiotic-resistant bacteria and, if so, identify the underlying genetic basis. Plastic panels with one side painted with copper and zinc-containing antifouling paint were submerged in a Swedish marina and biofilms from both sides of the panels were harvested after 2.5-4weeks. DNA was isolated from the biofilms and subjected to metagenomic sequencing. Biofilm bacteria were cultured on marine agar supplemented with tetracycline, gentamicin, copper sulfate or zinc sulfate. Biofilm communities from painted surfaces displayed lower taxonomic diversity and enrichment of Gammaproteobacteria. Bacteria from these communities showed increased resistance to both heavy metals and tetracycline but not to gentamicin. Significantly higher abundance of metal and biocide resistance genes was observed, whereas mobile antibiotic resistance genes were not enriched in these communities. In contrast, we found an enrichment of chromosomal RND efflux system genes, including such with documented ability to confer decreased susceptibility to both antibiotics and biocides/heavy metals. This was paralleled by increased abundances of integron-associated integrase and ISCR transposase genes. The results show that the heavy metal-based antifouling paint exerts a strong selection pressure on marine bacterial communities and can co-select for certain antibiotic-resistant bacteria, likely by favoring species and strains carrying genes that provide cross-resistance. Although this does not indicate an immediate risk for promotion of mobile antibiotic resistance, the

  17. Antibiotic resistance of bacterial biofilms

    DEFF Research Database (Denmark)

    Hoiby, N.; Bjarnsholt, T.; Givskov, M.

    2010-01-01

    A biofilm is a structured consortium of bacteria embedded in a self-produced polymer matrix consisting of polysaccharide, protein and DNA. Bacterial biofilms cause chronic infections because they show increased tolerance to antibiotics and disinfectant chemicals as well as resisting phagocytosis...... and other components of the body's defence system. The persistence of, for example, staphylococcal infections related to foreign bodies is due to biofilm formation. Likewise, chronic Pseudomonas aeruginosa lung infection in cystic fibrosis patients is caused by biofilm-growing mucoid strains....... Characteristically, gradients of nutrients and oxygen exist from the top to the bottom of biofilms and these gradients are associated with decreased bacterial metabolic activity and increased doubling times of the bacterial cells; it is these more or less dormant cells that are responsible for some of the tolerance...

  18. Off-label abuse of antibiotics by bacteria.

    Science.gov (United States)

    Viswanathan, V K

    2014-01-01

    Antibiotics and antibiotic resistance made news on several fronts in the past year. Many public health organizations, including the CDC, used terms such as "crisis", "catastrophic consequences", and "nightmare scenario" to highlight the rapid emergence and spread of antibiotic resistance. A report from the Pew Commission on Industrial Farm Animal Production, on the fifth anniversary of the publication of its landmark 2008 report, noted that state and federal legislative efforts to limit non-therapeutic use of antibiotics in animal production were thwarted by drug and food animal industries. In its lobbying disclosures, the Farm Bureau stated that such efforts to limit use of animal antibiotics were "based on emotion and no credible peer reviewed science." Meanwhile, there have been inexorable advances in our understanding of the molecular mechanisms by which antibiotics induce diversity and resistance in bacteria. This article reviews one study that probed the role of the bacterial general stress response in sub-inhibitory antibiotic-induced mutagenesis and antibiotic resistance.

  19. [Virulence and its relationship to antibiotic resistance].

    Science.gov (United States)

    Joly-Guillou, M L

    1998-12-01

    PATHOGENIC ISLANDS: Certain DNA blocks inserted into the chromosome of most Gram negative bacteria originated in pathogens found in plants. VIRULENCE-ANTIBIOTIC INTERACTIONS: During the invasive phase, the bacterial cell covers itself with adhesins which facilitate its adherence to tissues. The bacterial cell produces a fibronectin which protects its defense systems. Antibiotics favor bacterial resistance by increasing the expression of surface adhesins and fibronectin production. PENICILLIN RESISTANT PNEUMOCOCCI: Experimental models have demonstrated that mortality in mice and host resistance to pneumococcal infection are related to the type of capsule and not to antibiotic resistance. QUORUM SENSING: The bacterial inoculum regulates the production of virulence factors in vivo via quorum sensing. This regulation can play an important role in Pseudomonas aeruginosa infections. ACINETOBACTER BAUMANNI VIRULENCE: Long poorly understood, factors favoring A. baumanni virulence appear to result from bacterial production of IROMPs in the extracellular growth medium in response to iron depletion during the exponential growth phase.

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

    Science.gov (United States)

    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.

  1. Sensitivity of certain bacteria to antibiotics and irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Harsojo,; Andini, L S; Siagian, E G; Lina, M R; Zuleiha, S [National Atomic Energy Agency, Jakarta (Indonesia). Pasar Djumat Research Centre

    1981-07-01

    An experiment has been conducted to find vegetative forms of certain bacteria in Indonesia which are resistant to irradiation, the resistance of which will be compared to that of known radioresistant bacteria micrococcus radiodurans. To inactivate the vegetative forms of resistant bacteria to irradiation high doses are needed, while for storage purposes lower doses change the physical and chemical properties of the stored commodity are preferred. For this purpose the bacteria were irradiated in aerobic condition with gamma radiation doses of 0.1, 0.2 and 0.3 kGy, or treated with antibiotics e.g. tetracycline HCl or chloramphenicol with concentrations of 0.1, 0.2 and 0.3 ..mu..g/ml respectively. The results indicated that doses of 0.2 kGy and 0.1 ..mu..g/ml reduced the ability of the bacteria for multiplication.

  2. Fighting antibiotic resistance in the intensive care unit using antibiotics.

    Science.gov (United States)

    Plantinga, Nienke L; Wittekamp, Bastiaan H J; van Duijn, Pleun J; Bonten, Marc J M

    2015-01-01

    Antibiotic resistance is a global and increasing problem that is not counterbalanced by the development of new therapeutic agents. The prevalence of antibiotic resistance is especially high in intensive care units with frequently reported outbreaks of multidrug-resistant organisms. In addition to classical infection prevention protocols and surveillance programs, counterintuitive interventions, such as selective decontamination with antibiotics and antibiotic rotation have been applied and investigated to control the emergence of antibiotic resistance. This review provides an overview of selective oropharyngeal and digestive tract decontamination, decolonization of methicillin-resistant Staphylococcus aureus and antibiotic rotation as strategies to modulate antibiotic resistance in the intensive care unit.

  3. Cooperative Antibiotic Resistance in a Multi-Drug Environment

    Science.gov (United States)

    Yurtsev, Eugene; Dai, Lei; Gore, Jeff

    2013-03-01

    The emergence of antibiotic resistance in bacteria is a significant health concern. A frequent mechanism of antibiotic resistance involves the production of an enzyme which inactivates the antibiotic. By inactivating the antibiotic, resistant cells can ``share'' their resistance with other cells in the bacterial population, suggesting that it may be possible to observe cooperation between strains that inactivate different antibiotics. Here, we experimentally track the population dynamics of two E. coli strains in the presence of two different antibiotics. We find that together the strains are able to grow in antibiotic concentrations that inhibit growth of either of the strains individually. We observe that even when there is stable coexistence between the two strains, the population size of each strain can undergo large oscillations. We expect that our results will provide insight into the evolution of antibiotic resistance and the evolutionary origin of phenotypic diversity and cooperative behaviors.

  4. Environmental dissemination of antibiotic resistance genes and correlation to anthropogenic contamination with antibiotics

    Science.gov (United States)

    Berglund, Björn

    2015-01-01

    Antibiotic resistance is a growing problem which threatens modern healthcare globally. Resistance has traditionally been viewed as a clinical problem, but recently non-clinical environments have been highlighted as an important factor in the dissemination of antibiotic resistance genes (ARGs). Horizontal gene transfer (HGT) events are likely to be common in aquatic environments; integrons in particular are well suited for mediating environmental dissemination of ARGs. A growing body of evidence suggests that ARGs are ubiquitous in natural environments. Particularly, elevated levels of ARGs and integrons in aquatic environments are correlated to proximity to anthropogenic activities. The source of this increase is likely to be routine discharge of antibiotics and resistance genes, for example, via wastewater or run-off from livestock facilities and agriculture. While very high levels of antibiotic contamination are likely to select for resistant bacteria directly, the role of sub-inhibitory concentrations of antibiotics in environmental antibiotic resistance dissemination remains unclear. In vitro studies have shown that low levels of antibiotics can select for resistant mutants and also facilitate HGT, indicating the need for caution. Overall, it is becoming increasingly clear that the environment plays an important role in dissemination of antibiotic resistance; further studies are needed to elucidate key aspects of this process. Importantly, the levels of environmental antibiotic contamination at which resistant bacteria are selected for and HGT is facilitated at should be determined. This would enable better risk analyses and facilitate measures for preventing dissemination and development of antibiotic resistance in the environment. PMID:26356096

  5. Predictable Phenotypes of Antibiotic Resistance Mutations.

    Science.gov (United States)

    Knopp, M; Andersson, D I

    2018-05-15

    Antibiotic-resistant bacteria represent a major threat to our ability to treat bacterial infections. Two factors that determine the evolutionary success of antibiotic resistance mutations are their impact on resistance level and the fitness cost. Recent studies suggest that resistance mutations commonly show epistatic interactions, which would complicate predictions of their stability in bacterial populations. We analyzed 13 different chromosomal resistance mutations and 10 host strains of Salmonella enterica and Escherichia coli to address two main questions. (i) Are there epistatic interactions between different chromosomal resistance mutations? (ii) How does the strain background and genetic distance influence the effect of chromosomal resistance mutations on resistance and fitness? Our results show that the effects of combined resistance mutations on resistance and fitness are largely predictable and that epistasis remains rare even when up to four mutations were combined. Furthermore, a majority of the mutations, especially target alteration mutations, demonstrate strain-independent phenotypes across different species. This study extends our understanding of epistasis among resistance mutations and shows that interactions between different resistance mutations are often predictable from the characteristics of the individual mutations. IMPORTANCE The spread of antibiotic-resistant bacteria imposes an urgent threat to public health. The ability to forecast the evolutionary success of resistant mutants would help to combat dissemination of antibiotic resistance. Previous studies have shown that the phenotypic effects (fitness and resistance level) of resistance mutations can vary substantially depending on the genetic context in which they occur. We conducted a broad screen using many different resistance mutations and host strains to identify potential epistatic interactions between various types of resistance mutations and to determine the effect of strain

  6. A systematic review and meta-analysis of the effects of antibiotic consumption on antibiotic resistance.

    NARCIS (Netherlands)

    Bell, B.G.; Schellevis, F.; Stobberingh, E.; Goossen, H.; Pringle, M.

    2014-01-01

    Background: Greater use of antibiotics during the past 50 years has exerted selective pressure on susceptible bacteria and may have favoured the survival of resistant strains. Existing information on antibiotic resistance patterns from pathogens circulating among community-based patients is

  7. A systematic review and meta-analysis of the effects of antibiotic consumption on antibiotic resistance

    NARCIS (Netherlands)

    Bell, B.G.; Schellevis, F.; Stobberingh, E.; Goossens, H.; Pringle, M.

    2014-01-01

    Background: Greater use of antibiotics during the past 50 years has exerted selective pressure on susceptible bacteria and may have favoured the survival of resistant strains. Existing information on antibiotic resistance patterns from pathogens circulating among community-based patients is

  8. Natural attenuation in a surface water channel and a coastal aquifer by monitoring presence and removal of indicator bacteria, pathogens and antibiotic resistance gene: model development

    Science.gov (United States)

    Masciopinto, Costantino; Visino, Fabrizio; Luprano, Maria Laura; Levantesi, Caterina; Tandoi, Valter

    2015-04-01

    The spreading of microbial contamination into the environment, represents a very relevant problem, which leads to an increasing health concern. For this reason, it is important to identify and characterize the extent of natural depuration in water environmental particularly for reducing the presence of faecal contamination indicator bacteria, pathogens and antibiotic resistance genes (ARG). In this study, the presence of the above reported microbial parameters was analyzed in a surface water channel and in a coastal aquifer in southern Italy (Ostuni) southern Italy, both affected by Ostuni municipal treatment plant effluents and by local run-off. Several samples were collected from surface water, flowing in channels, and from wells in our study area. In particular, the water samples were analyzed to detect 7 fecal contamination indicators (E. coli, total coliforms, Clostridium p. spores, somatic coliphages, Enterococci and heterotrophic bacteria), Salmonella spp and the presence of ARGs. The water samples were also tested for chemical constituents. Finally a mathematical model has been developed in order to simulate pathogen migration pathways in the fractured groundwater and corresponding possible mitigation of pathogens in pumping wells.

  9. Third generation cephalosporin resistant Enterobacteriaceae and multidrug resistant gram-negative bacteria causing bacteremia in febrile neutropenia adult cancer patients in Lebanon, broad spectrum antibiotics use as a major risk factor, and correlation with poor prognosis

    Directory of Open Access Journals (Sweden)

    Rima eMoghnieh

    2015-02-01

    Full Text Available Bacteremia remains a major cause of life-threatening complications in patients receiving anticancer chemotherapy. The spectrum and susceptibility profiles of causative microorganisms differ with time and place. Data from Lebanon are scarce. We aim at evaluating the epidemiology of bacteremia in cancer patients in a university hospital in Lebanon, emphasizing antibiotic resistance and risk factors of multi-drug resistant organism (MDRO-associated bacteremia.This is a retrospective study of 75 episodes of bacteremia occurring in febrile neutropenic patients admitted to the hematology-oncology unit at Makassed General Hospital, Lebanon, from October 2009-January 2012.It corresponds to epidemiological data on bacteremia episodes in febrile neutropenic cancer patients including antimicrobial resistance and identification of risk factors associated with third generation cephalosporin resistance (3GCR and MDRO-associated bacteremia. Out of 75 bacteremias, 42.7% were gram-positive (GP, and 57.3% were gram-negative (GN. GP bacteremias were mostly due to methicillin-resistant coagulase negative staphylococci (28% of total bacteremias and 66% of GP bacteremias. Among the GN bacteremias, Escherichia coli (22.7% of total, 39.5% of GN organisms and Klebsiellapneumoniae(13.3% of total, 23.3% of GN organisms were the most important causative agents. GN bacteremia due to 3GC sensitive (3GCS bacteria represented 28% of total bacteremias, while 29% were due to 3GCR bacteria and 9% were due to carbapenem-resistant organisms. There was a significant correlation between bacteremia with MDRO and subsequent intubation, sepsis and mortality. Among potential risk factors, only broad spectrum antibiotic intake >4 days before bacteremia was found to be statistically significant for acquisition of 3GCR bacteria. Using carbapenems or piperacillin/ tazobactam>4 days before bacteremia was significantly associated with the emergence of MDRO (p value<0.05.

  10. Research progress on distribution, migration, transformation of antibiotics and antibiotic resistance genes (ARGs) in aquatic environment.

    Science.gov (United States)

    Shao, Sicheng; Hu, Yongyou; Cheng, Jianhua; Chen, Yuancai

    2018-05-28

    Antimicrobial and antibiotics resistance caused by misuse or overuse of antibiotics exposure is a growing and significant threat to global public health. The spread and horizontal transfer of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) by the selective pressure of antibiotics in an aquatic environment is a major public health issue. To develop a better understanding of potential ecological risks die to antibiotics and ARGs, this study mainly summarizes research progress about: (i) the occurrence, concentration, fate, and potential ecological effects of antibiotics and ARGs in various aquatic environments, (ii) the threat, spread, and horizontal gene transfer (HGT) of ARGs, and (iii) the relationship between antibiotics, ARGs, and ARB. Finally, this review also proposes future research direction on antibiotics and ARGs.

  11. Transmission of antibiotic resistance from animals to humans

    NARCIS (Netherlands)

    Huijbers, P.M.C.

    2016-01-01

    Huijbers, P.M.C. (2016). Transmission of antibiotic resistance from animals to humans: Broilers as a reservoir of ESBL-producing bacteria. PhD thesis, Wageningen University, Wageningen, the Netherlands.

    Antibiotic resistance in animals becomes a public health issue when there is

  12. Anaerobic bacteria as producers of antibiotics.

    Science.gov (United States)

    Behnken, Swantje; Hertweck, Christian

    2012-10-01

    Anaerobic bacteria are the oldest terrestrial creatures. They occur ubiquitously in soil and in the intestine of higher organisms and play a major role in human health, ecology, and industry. However, until lately no antibiotic or any other secondary metabolite has been known from anaerobes. Mining the genome sequences of Clostridium spp. has revealed a high prevalence of putative biosynthesis genes (PKS and NRPS), and only recently the first antibiotic from the anaerobic world, closthioamide, has been isolated from the cellulose degrading bacterium Clostridium cellulolyticum. The successful genetic induction of antibiotic biosynthesis in an anaerobe encourages further investigations of obligate anaerobes to tap their hidden biosynthetic potential.

  13. Deoxyribonucleoside kinases activate nucleoside antibiotics in severely pathogenic bacteria

    DEFF Research Database (Denmark)

    Sandrini, Michael; Shannon, O.; Clausen, A.R.

    2007-01-01

    Common bacterial pathogens are becoming progressively more resistant to traditional antibiotics, representing a major public-health crisis. Therefore, there is a need for a variety of antibiotics with alternative modes of action. In our study, several nucleoside analogs were tested against pathog...... alternative for combating pathogenic bacteria.......Common bacterial pathogens are becoming progressively more resistant to traditional antibiotics, representing a major public-health crisis. Therefore, there is a need for a variety of antibiotics with alternative modes of action. In our study, several nucleoside analogs were tested against...... pathogenic staphylococci and streptococci. We show that pyrimidine-based nucleoside analogs, like 3'-azido-3'-deoxythymidine (AZT) and 2',2'-difluoro-2'deoxycytidine (gemcitabine), are specifically activated by the endogenous bacterial deoxyribonucleoside kinases, leading to cell death. Deoxyribonucleoside...

  14. Detection and characterisation of genes encoding antibiotic resistance in the cultivable oral microflora.

    OpenAIRE

    Villedieu, A.

    2006-01-01

    The emergence of antibiotic-resistant bacteria has become a major threat to public health. The increased use of antibiotics has selected for the dissemination of antibiotic resistance genes between organisms from different species and different genera. There is a large body of evidence that the indigenous microbiota can act as a reservoir of antibiotic-resistant bacteria. However little is known about the molecular basis for this in bacteria from the oral cavity. Therefore the aim of this wor...

  15. Handling Time-dependent Variables : Antibiotics and Antibiotic Resistance

    NARCIS (Netherlands)

    Munoz-Price, L. Silvia; Frencken, Jos F.; Tarima, Sergey; Bonten, Marc

    2016-01-01

    Elucidating quantitative associations between antibiotic exposure and antibiotic resistance development is important. In the absence of randomized trials, observational studies are the next best alternative to derive such estimates. Yet, as antibiotics are prescribed for varying time periods,

  16. At the Nexus of Antibiotics and Metals: The Impact of Cu and Zn on Antibiotic Activity and Resistance.

    Science.gov (United States)

    Poole, Keith

    2017-10-01

    Environmental influences on antibiotic activity and resistance can wreak havoc with in vivo antibiotic efficacy and, ultimately, antimicrobial chemotherapy. In nature, bacteria encounter a variety of metal ions, particularly copper (Cu) and zinc (Zn), as contaminants in soil and water, as feed additives in agriculture, as clinically-used antimicrobials, and as components of human antibacterial responses. Importantly, there is a growing body of evidence for Cu/Zn driving antibiotic resistance development in metal-exposed bacteria, owing to metal selection of genetic elements harbouring both metal and antibiotic resistance genes, and metal recruitment of antibiotic resistance mechanisms. Many classes of antibiotics also form complexes with metal cations, including Cu and Zn, and this can hinder (or enhance) antibiotic activity. This review highlights the ways in which Cu/Zn influence antibiotic resistance development and antibiotic activity, and in so doing impact in vivo antibiotic efficacy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Cross-Contamination of Residual Emerging Contaminants and Antibiotic Resistant Bacteria in Lettuce Crops and Soil Irrigated with Wastewater Treated by Sunlight/H2O2.

    Science.gov (United States)

    Ferro, Giovanna; Polo-López, María I; Martínez-Piernas, Ana B; Fernández-Ibáñez, Pilar; Agüera, Ana; Rizzo, Luigi

    2015-09-15

    The sunlight/H2O2 process has recently been considered as a sustainable alternative option compared to other solar driven advanced oxidation processes (AOPs) in advanced treatment of municipal wastewater (WW) to be reused for crop irrigation. Accordingly, in this study sunlight/H2O2 was used as disinfection/oxidation treatment for urban WW treatment plant effluent in a compound parabolic collector photoreactor to assess subsequent cross-contamination of lettuce and soil by contaminants of emerging concern (CECs) (determined by QuEChERS extraction and LC-QqLIT-MS/MS analysis) and antibiotic resistant (AR) bacteria after irrigation with treated WW. Three CECs (carbamazepine (CBZ), flumequine (FLU), and thiabendazole (TBZ) at 100 μg L(-1)) and two AR bacterial strains (E. coli and E. faecalis, at 10(5) CFU mL(-1)) were spiked in real WW. A detection limit (DL) of 2 CFU mL(-1) was reached after 120 min of solar exposure for AR E. coli, while AR E. faecalis was more resistant to the disinfection process (240 min to reach DL). CBZ and TBZ were poorly removed after 90 min (12% and 50%, respectively) compared to FLU (94%). Lettuce was irrigated with treated WW for 5 weeks. CBZ and TBZ were accumulated in soil up to 472 ng g(-1) and 256 ng g(-1) and up-taken by lettuce up to 109 and 18 ng g(-1), respectively, when 90 min treated WW was used for irrigation; whereas no bacteria contamination was observed when the bacterial density in treated WW was below the DL. A proper treatment time (>90 min) should be guaranteed in order to avoid the transfer of pathogens from disinfected WW to irrigated crops and soil.

  18. Isolation of antibiotic-resistant pathogenic and potentially ...

    African Journals Online (AJOL)

    2010-09-13

    Sep 13, 2010 ... The aim of the present study is to determine the pathogenic and potentially ... Keywords: pathogenic bacteria; antibiotic resistance; carpets; mosques; Tripoli; Libya .... During the process of praying, a Muslim is obliged to go.

  19. Detection of antibiotic resistance in probiotics of dietary supplements

    KAUST Repository

    Wong, Aloysius Tze; Ngu, Davey Yueh Saint; Dan, Lydia Annabel; Ooi, Amanda Siok Lee; Lim, Renee Lay Hong

    2015-01-01

    in food and health products. Since probiotic bacteria act as reservoir for antibiotic resistant determinants, the transfer of these genes to pathogens sharing the same intestinal habitat is thus conceivable considering the fact that dietary supplements

  20. Emergence and dissemination of antibiotic resistance: A global problem

    Directory of Open Access Journals (Sweden)

    R Choudhury

    2012-01-01

    Full Text Available Antibiotic resistance is a major problem in clinical health settings. Interestingly the origin of many of antibiotic resistance mechanisms can be traced back to non-pathogenic environmental organisms. Important factors leading to the emergence and spread of antibiotic resistance include absence of regulation in the use of antibiotics, improper waste disposal and associated transmission of antibiotic resistance genes in the community through commensals. In this review, we discussed the impact of globalisation on the transmission of antibiotic resistance genes in bacteria through immigration and export/import of foodstuff. The significance of surveillance to define appropriate use of antibiotics in the clinic has been included as an important preventive measure.

  1. Nanostructured coatings for controlling bacterial biofilms and antibiotic resistance

    OpenAIRE

    Ivanova, Kristina Dimitrova

    2017-01-01

    The accelerated emergence of drug resistant bacteria is one of the most serious problems in healthcare and the difficulties in finding new antibiotics make it even more challenging. To overcome the action of antibiotics bacteria develop effective resistance mechanisms including the formation of biofilms. Biofilms are bacterial communities of cells embedded in a self-produced polymeric matrix commonly found on medical devices such as indwelling catheters. When pathogens adopt this mode of grow...

  2. Antibiotic Resistant Microbiota in the Swine Intestinal Tract

    Science.gov (United States)

    The healthy swine intestine is populated by upwards of 500 bacterial species, mainly obligate anaerobes. Our research focuses on the roles of these commensal bacteria in antimicrobial resistance and on interventions to reduce the prevalence of antibiotic resistant bacteria. In comparisons of intes...

  3. Antibiotic Resistance in Intensive Care Units: Dynamics of Colonization

    NARCIS (Netherlands)

    Nijssen, S.

    2006-01-01

    The dynamics of colonization of antibiotic-resistant bacteria in hospital settings are complex and depend on bacteria and healthcare worker related characteristics. Many factors influence colonization and in addition these factors interact with each other as well. Knowledge of local resistance

  4. Antibiotics and the resistant microbiome

    DEFF Research Database (Denmark)

    Sommer, Morten; Dantas, Gautam

    2011-01-01

    . Less appreciated are the concomitant changes in the human microbiome in response to these assaults and their contribution to clinical resistance problems. Studies have shown that pervasive changes to the human microbiota result from antibiotic treatment and that resistant strains can persist for years....... Additionally, culture-independent functional characterization of the resistance genes from the microbiome has demonstrated a close evolutionary relationship between resistance genes in the microbiome and in pathogens. Application of these techniques and novel cultivation methods are expected to significantly...... expand our understanding of the interplay between antibiotics and the microbiome....

  5. H2S: a universal defense against antibiotics in bacteria.

    Science.gov (United States)

    Shatalin, Konstantin; Shatalina, Elena; Mironov, Alexander; Nudler, Evgeny

    2011-11-18

    Many prokaryotic species generate hydrogen sulfide (H(2)S) in their natural environments. However, the biochemistry and physiological role of this gas in nonsulfur bacteria remain largely unknown. Here we demonstrate that inactivation of putative cystathionine β-synthase, cystathionine γ-lyase, or 3-mercaptopyruvate sulfurtransferase in Bacillus anthracis, Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli suppresses H(2)S production, rendering these pathogens highly sensitive to a multitude of antibiotics. Exogenous H(2)S suppresses this effect. Moreover, in bacteria that normally produce H(2)S and nitric oxide, these two gases act synergistically to sustain growth. The mechanism of gas-mediated antibiotic resistance relies on mitigation of oxidative stress imposed by antibiotics.

  6. Antibiotics as CECs: An Overview of the Hazards Posed by Antibiotics and Antibiotic Resistance

    Directory of Open Access Journals (Sweden)

    Geoffrey Ivan Scott

    2016-04-01

    Full Text Available ABSTRACTMonitoring programs have traditionally monitored legacy contaminants but are shifting focus to Contaminants of Emerging Concern (CECs. CECs present many challenges for monitoring and assessment, because measurement methods don't always exist nor have toxicological studies been fully conducted to place results in proper context. Also some CECs affect metabolic pathways to produce adverse outcomes that are not assessed through traditional toxicological evaluations. Antibiotics are CECs that pose significant environmental risks including development of both toxic effects at high doses and antibiotic resistance at doses well below the Minimum Inhibitory Concentration (MIC which kill bacteria and have been found in nearly half of all sites monitored in the US. Antimicrobial resistance has generally been attributed to the use of antibiotics in medicine for humans and livestock as well as aquaculture operations. The objective of this study was to assess the extent and magnitude of antibiotics in the environment and estimate their potential hazards in the environment. Antibiotics concentrations were measured in a number of monitoring studies which included Waste Water Treatment Plants (WWTP effluent, surface waters, sediments and biota. A number of studies reported levels of Antibiotic Resistant Microbes (ARM in surface waters and some studies found specific ARM genes (e.g. the blaM-1 gene in E. coli which may pose additional environmental risk. High levels of this gene were found to survive WWTP disinfection and accumulated in sediment at levels 100-1000 times higher than in the sewerage effluent, posing potential risks for gene transfer to other bacteria.in aquatic and marine ecosystems. Antibiotic risk assessment approaches were developed based on the use of MICs and MIC Ratios [High (Antibiotic Resistant/Low (Antibiotic Sensitive MIC] for each antibiotic indicating the range of bacterial adaptability to each antibiotic to help define the No

  7. PREVALENCE AND ANTIBIOTIC RESISTANCE OF ...

    African Journals Online (AJOL)

    9 mars 2015 ... strategy to prevent the spread of this resistance. Keywords: Staphylococci; Staphylococcus aureus; Oxacillin; Antibiotic resistance; Disc diffusion. Author Correspondence, e-mail: mn.boukhatem@yahoo.fr. ICID: 1142924. Journal of Fundamental and Applied Sciences. ISSN 1112-9867. Available online at.

  8. The determinants of the antibiotic resistance process.

    Science.gov (United States)

    Franco, Beatriz Espinosa; Altagracia Martínez, Marina; Sánchez Rodríguez, Martha A; Wertheimer, Albert I

    2009-01-01

    The use of antibiotic drugs triggers a complex interaction involving many biological, sociological, and psychological determinants. Resistance to antibiotics is a serious worldwide problem which is increasing and has implications for morbidity, mortality, and health care both in hospitals and in the community. To analyze current research on the determinants of antibiotic resistance and comprehensively review the main factors in the process of resistance in order to aid our understanding and assessment of this problem. We conducted a MedLine search using the key words "determinants", "antibiotic", and "antibiotic resistance" to identify publications between 1995 and 2007 on the determinants of antibiotic resistance. Publications that did not address the determinants of antibiotic resistance were excluded. The process and determinants of antibiotic resistance are described, beginning with the development of antibiotics, resistance and the mechanisms of resistance, sociocultural determinants of resistance, the consequences of antibiotic resistance, and alternative measures proposed to combat antibiotic resistance. Analysis of the published literature identified the main determinants of antibiotic resistance as irrational use of antibiotics in humans and animal species, insufficient patient education when antibiotics are prescribed, lack of guidelines for treatment and control of infections, lack of scientific information for physicians on the rational use of antibiotics, and lack of official government policy on the rational use of antibiotics in public and private hospitals.

  9. Development of botanicals to combat antibiotic resistance

    Directory of Open Access Journals (Sweden)

    Pooja D. Gupta

    2017-10-01

    Full Text Available The discovery of antibiotics in the previous century lead to reduction in mortality and morbidity due to infectious diseases but their inappropriate and irrational use has resulted in emergence of resistant microbial populations. Alteration of target sites, active efflux of drugs and enzymatic degradations are the strategies employed by the pathogenic bacteria to develop intrinsic resistance to antibiotics. This has led to an increased interest in medicinal plants since 25–50% of current pharmaceuticals are plant derived. Crude extracts of medicinal plants could serve as an alternate source of resistance modifying agents owing to the wide variety of secondary metabolites. These metabolites (alkaloids, tannins, polyphenols etc. could act as potentials for antimicrobials and resistance modifiers. Plant extracts have the ability to bind to protein domains leading to modification or inhibition protein–protein interactions. This enables the herbals to also present themselves as effective modulators of host related cellular processes viz immune response, mitosis, apoptosis and signal transduction. Thus they may exert their activity not only by killing the microorganism but by affecting key events in the pathogenic process, thereby, the bacteria, fungi and viruses may have a reduced ability to develop resistance to botanicals. The article is meant to stimulate research wherein the cidal activity of the extract is not the only parameter considered but other mechanism of action by which plants can combat drug resistant microbes are investigated. The present article emphasizes on mechanisms involved in countering multi drug resistance.

  10. Prevalence of antibiotics and antibiotic resistance genes in a wastewater effluent-receiving river in the Netherlands

    NARCIS (Netherlands)

    Sabri, N.A.; Schmitt, H.; Zaan, Van der B.; Gerritsen, H.W.; Zuidema, T.; Rijnaarts, H.H.M.; Langenhoff, A.A.M.

    2018-01-01

    Antibiotics are being used intensively for humans and livestock worldwide and have led to the presence of antibiotic resistance bacteria (ARB) and antibiotic resistance genes (ARGs) in the environment. Wastewater treatment plants (WWTPs) have been identified as a point source for ARB&Gs, and

  11. Antibiotic and Antimicrobial Resistance: Threat Report 2013

    Science.gov (United States)

    ... Form Controls Cancel Submit Search The CDC Antibiotic / Antimicrobial Resistance Note: Javascript is disabled or is not ... please visit this page: About CDC.gov . Antibiotic / Antimicrobial Resistance About Antimicrobial Resistance Biggest Threats Emerging Drug ...

  12. Genetic Mechanisms of Antibiotic Resistance and the Role of Antibiotic Adjuvants.

    Science.gov (United States)

    Pontes, Daniela Santos; de Araujo, Rodrigo Santos Aquino; Dantas, Natalina; Scotti, Luciana; Scotti, Marcus Tullius; de Moura, Ricardo Olimpio; Mendonca-Junior, Francisco Jaime Bezerra

    2018-01-01

    The ever increasing number of multidrug-resistant microorganism pathogens has become a great and global public health threat. Antibiotic mechanisms of action and the opposing mechanisms of resistance are intimately associated, but comprehension of the biochemical and molecular functions of such drugs is not a simple exercise. Both the environment, and genetic settings contribute to alterations in phenotypic resistance (natural bacterial evolution), and make it difficult to control the emergence and impacts of antibiotic resistance. Under such circumstances, comprehension of how bacteria develop and/or acquire antibiotic resistance genes (ARG) has a critical role in developing propositions to fight against these superbugs, and to search for new drugs. In this review, we present and discuss both general information and examples of common genetic and molecular mechanisms related to antibiotic resistance, as well as how the expression and interactions of ARGs are important to drug resistance. At the same time, we focus on the recent achievements in the search for antibiotic adjuvants, which help combat antibiotic resistance through deactivation of bacterial mechanisms of action such as β-lactamases. Recent advances involving the use of anti-resistance drugs such as: efflux pump inhibitors; anti-virulence drugs; drugs against quorum sensing; and against type II/III secretion systems are revealed. Such antibiotic adjuvants (as explored herein) collaborate against the problems of antibiotic resistance, and may restore or prolong the therapeutic activity of known antibiotics. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  13. Appropriateness of antibiotic prescription for targeted therapy of infections caused by multidrug-resistant bacteria: assessment of the most common improper uses in a tertiary hospital in southern Italy.

    Science.gov (United States)

    Viceconte, Giulio; Maraolo, Alberto Enrico; Iula, Vita Dora; Catania, Maria Rosaria; Tosone, Grazia; Orlando, Raffaele

    2017-09-01

    A huge proportion of antibiotic therapies for infections caused by multidrug-resistant bacteria (MDR) are inappropriate. In this study, we described the most common causes of inappropriateness of definitive antibiotic regimes in a large university hospital in southern Italy and we evaluated the impact on microbial eradication, length of stay, 30-day readmission and mortality. We retrospectively assessed 45 patients who received a definitive antibiotic therapy after isolation of multidrug-resistant Staphylococcus aureus, Enterococcus spp., Enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter spp. strains between 2014 and 2015. From the literature, we set a series of criteria to retrospectively determine the appropriateness of the therapy. In all, 61% of the prescribed antibiotic regimes were found to be inappropriate, especially due to incorrect drug dosage. It emerged that meropenem was the antibiotic most frequently inappropriately used. In 46% of infections caused by MDR but not extended-spectrum β-lactamase-producing Enterobacteriaceae, carbapenems were inappropriately administered. Microbial eradication was achieved in 87% of the appropriate therapy group compared to 31% of the inappropriate therapy group (chi-square=6.750, p<0.027). No statistically significant association was found between inappropriate therapy and the length of stay (chi-square=3.084, p=0.101) and 30-day readmission (p=0.103). Definitive antibiotic therapy in infections caused by multidrug-resistant bacteria in a large university hospital is often inappropriate, especially due to the drug dosing regimen, particularly in the case of meropenem and colistin. This inappropriateness has a significant impact on post-treatment microbial eradication in specimens collected after antibiotic therapy.

  14. Sensitivity of antibiotic resistant and antibiotic susceptible Escherichia coli, Enterococcus and Staphylococcus strains against ozone.

    Science.gov (United States)

    Heß, Stefanie; Gallert, Claudia

    2015-12-01

    Tolerance of antibiotic susceptible and antibiotic resistant Escherichia coli, Enterococcus and Staphylococcus strains from clinical and wastewater samples against ozone was tested to investigate if ozone, a strong oxidant applied for advanced wastewater treatment, will affect the release of antibiotic resistant bacteria into the aquatic environment. For this purpose, the resistance pattern against antibiotics of the mentioned isolates and their survival after exposure to 4 mg/L ozone was determined. Antibiotic resistance (AR) of the isolates was not correlating with higher tolerance against ozone. Except for ampicillin resistant E. coli strains, which showed a trend towards increased resistance, E. coli strains that were also resistant against cotrimoxazol, ciprofloxacin or a combination of the three antibiotics were similarly or less resistant against ozone than antibiotic sensitive strains. Pigment-producing Enterococcus casseliflavus and Staphylococcus aureus seemed to be more resistant against ozone than non-pigmented species of these genera. Furthermore, aggregation or biofilm formation apparently protected bacteria in subsurface layers from inactivation by ozone. The relatively large variance of tolerance against ozone may indicate that resistance to ozone inactivation most probably depends on several factors, where AR, if at all, does not play a major role.

  15. Composting swine slurry to reduce indicators and antibiotic resistance genes

    Science.gov (United States)

    Over the last twenty years there have been considerable increases in the incidence of human infections with bacteria that are resistant to commonly used antibiotics. This has precipitated concerns about the use of antibiotics in livestock production. Composting of swine manure has several advantages...

  16. Detection of antibiotic resistance in probiotics of dietary supplements

    KAUST Repository

    Wong, Aloysius Tze

    2015-09-14

    Background Probiotics are live microorganisms that confer nutrition- and health-promoting benefits if consumed in adequate amounts. Concomitant with the demand for natural approaches to maintaining health is an increase in inclusion of probiotics in food and health products. Since probiotic bacteria act as reservoir for antibiotic resistant determinants, the transfer of these genes to pathogens sharing the same intestinal habitat is thus conceivable considering the fact that dietary supplements contain high amounts of often heterogeneous populations of probiotics. Such events can confer pathogens protection against commonly-used drugs. Despite numerous reports of antibiotic resistant probiotics in food and biological sources, the antibiogram of probiotics from dietary supplements remained elusive. Findings Here, we screened five commercially available dietary supplements for resistance towards antibiotics of different classes. Probiotics of all batches of products were resistant towards vancomycin while batch-dependent resistance towards streptomycin, aztreonam, gentamycin and/or ciprofloxacin antibiotics was detected for probiotics of brands Bi and Bn, Bg, and L. Isolates of brand Cn was also resistant towards gentamycin, streptomycin and ciprofloxacin antibiotics. Additionally, we also report a discrepancy between the enumerated viable bacteria amounts and the claims of the manufacturers. Conclusions This short report has highlighted the present of antibiotic resistance in probiotic bacteria from dietary supplements and therefore serves as a platform for further screenings and for in-depth characterization of the resistant determinants and the molecular machinery that confers the resistance.

  17. Insights into the structure, function and evolution of the radical-SAM 23S rRNA methyltransferase Cfr that confers antibiotic resistance in bacteria

    DEFF Research Database (Denmark)

    Karminska, K. H.; Purta, E.; Hansen, L .H.

    2010-01-01

    The Cfr methyltransferase confers combined resistance to five classes of antibiotics that bind to the peptidyl tranferase center of bacterial ribosomes by catalyzing methylation of the C-8 position of 23S rRNA nucleotide A2503. The same nucleotide is targeted by the housekeeping methyltransferase...

  18. Bacteriocins from lactic acid bacteria as an alternative to antibiotics

    Directory of Open Access Journals (Sweden)

    Aleksandra Ołdak

    2017-05-01

    Full Text Available Bacteriocins are ribosomally synthesized, proteinaceous substances that inhibit the growth of closely related species through numerous mechanisms. The classification system used in this review divided bacteriocins into four sub-groups based on their size. Currently, there is extensive research focused on bacteriocins and their usage as a food preservative.The increasing incidence of multidrug resistant bacterial pathogens is one of the most pressing medical problems in recent years. Recently, the potential clinical application of LAB (Lactic Acid Bacteria bacteriocin has been the subject of investigations by many scientists.Bacteriocins can be considered in a sense as antibiotic, although they differ from conventional antibiotics in numerous aspects. The gene-encoded nature of bacteriocins makes them easily amenable through bioengineering to either increase their activity or specify target microorganism. Owing to this feature of bacteriocins, antibiotic therapy would become less damaging to the natural gut microflora, which is a common drawback of conventional antibiotic use. Bacteriocins from lactic acid bacteria represent one of the most studied microbial defense systems and the idea of subjecting them to bioengineering to either increase antimicrobial activity or further specify their target microorganism is now a rapidly expanding field. This review aimed to present bacteriocins as a possible alternative to conventional antibiotics basic on latest scientific data.

  19. Antibiotics Resistance - Carbapenemase-producing germs in livestock populations

    OpenAIRE

    German Federal Institute for Risk Assessment

    2014-01-01

    Carbapenems are antibiotics authorised for the treatment of humans and which were categorised by the World Health Organization as critically important antimicrobials for the treatment of humans. Reserve antibiotics of this kind are only supposed to be used when standard antibiotics no longer show any effects, i.e. for only stricted indications. A mechanism that leads to a resistance of bacteria to carbapenems is the formation of certain enzymes called carbapenemases. What then happens is that...

  20. Coagulase-negative staphylococci: pathogenesis, occurrence of antibiotic resistance genes and in vitro effects of antimicrobial agents on biofilm-growing bacteria.

    Science.gov (United States)

    Szczuka, Ewa; Jabłońska, Lucyna; Kaznowski, Adam

    2016-12-01

    Coagulase-negative staphylococci (CoNS) are opportunistic pathogens that particularly cause infections in patients with implanted medical devices. The present research was performed to study the virulence potential of 53 clinical isolates of Staphylococcus capitis, Staphylococcus auricularis, Staphylococcus lugdunensis, Staphylococcus simulans, Staphylococcus cohnii and Staphylococcus caprae. All clinical strains were clonally unrelated. Isolates carried genes encoding resistance to β-lactam (mecA) (15 %), aminoglycoside [aac(6')/aph(2″)(11 %), aph (3')-IIIa (15 %), ant(4')-Ia (19 %)] and macrolide, lincosamide and streptogramin B (MLSB) [erm(A) (4 %), erm(B) (13 %), erm(C) (41 %), msr(A) (11 %)] antibiotics. CoNS isolates (64 %) were able to form biofilms. Confocal laser scanning microscopy revealed that these biofilms formed a three-dimensional structure composed mainly of living cells. All biofilm-positive strains carried the ica operon. In vitro studies demonstrated that a combination treatment with tigecycline and rifampicin was more effective against biofilms than one with ciprofloxacin and rifampicin. The minimum biofilm eradication concentration values were 0.062-0.5 µg ml-1 for tigecycline/rifampicin and 0.250-2 µg ml-1 for ciprofloxacin/rifampicin. All CoNS strains adhered to the human epithelial cell line HeLa, and more than half of the isolates were able to invade the HeLa cells, although most invaded relatively poorly. The virulence of CoNS is also attributed to their cytotoxic effects on HeLa cells. Incubation of HeLa cells with culture supernatant of the CoNS isolates resulted in cell death. The results indicate that the pathogenicity of S. capitis, S. auricularis, S. lugdunensis, S. cohnii and S. caprae is multi-factorial, involving the ability of these bacteria to adhere to human epithelial cells, form biofilms and invade and destroy human cells.

  1. Antibiotics and Resistance: Glossary

    Science.gov (United States)

    ... chromosomes and plasmids. Transposons often carry genes specifying antimicrobial resistance. Virus An extremely small infective agent, visible only with an electron microscope. Viruses can cause disease in humans, animals and plants. Viruses consist of a protein coat ...

  2. Antibiotics and antibiotic resistance in agroecosystems: State of the science

    Science.gov (United States)

    We propose a simple causal model depicting relationships involved in dissemination of antibiotics and antibiotic resistance in agroecosystems and potential effects on human health, functioning of natural ecosystems, and agricultural productivity. Available evidence for each causal link is briefly su...

  3. Prevalence of Antibiotic Resistance in Commensal Escherichia Coli among the Children in Rural Hill Communities of North East India

    OpenAIRE

    Lepcha, Yangchen; Pradhan, Nilu; Gajamer, Varsha; Singh, Samer; Das, Saurav; Tiwari, Ashish; Singh, Ashish

    2018-01-01

    Commensal bacteria are the representative of the reservoir of antibiotic resistance genes present in a community. Merely a few community-based studies on the prevalence of antibiotic resistance in commensal bacteria have been conducted so far in Southeast Asia and other parts of India. Northeastern India is still untapped regarding the surveillance of antibiotic-resistant genes and prevalence in commensal bacteria. In the present work, the prevalence of antibiotic resistance in commensal Esch...

  4. Dielectrophoretic assay of bacterial resistance to antibiotics

    International Nuclear Information System (INIS)

    Johari, Juliana; Huebner, Yvonne; Hull, Judith C; Dale, Jeremy W; Hughes, Michael P

    2003-01-01

    The dielectrophoretic collection spectra of antibiotic-sensitive and antibiotic-resistant strains of Staphylococcus epidermidis have been determined. These indicate that in the absence of antibiotic treatment there is a strong similarity between the dielectric properties of sensitive and resistant strains, and that there is a significant difference between the sensitive strains before and after treatment with the antibiotic streptomycin after 24 h exposure. This method offers possibilities for the assessment of bacterial resistance to antibiotics. (note)

  5. Genomics of antibiotic-resistance prediction in Pseudomonas aeruginosa.

    Science.gov (United States)

    Jeukens, Julie; Freschi, Luca; Kukavica-Ibrulj, Irena; Emond-Rheault, Jean-Guillaume; Tucker, Nicholas P; Levesque, Roger C

    2017-06-02

    Antibiotic resistance is a worldwide health issue spreading quickly among human and animal pathogens, as well as environmental bacteria. Misuse of antibiotics has an impact on the selection of resistant bacteria, thus contributing to an increase in the occurrence of resistant genotypes that emerge via spontaneous mutation or are acquired by horizontal gene transfer. There is a specific and urgent need not only to detect antimicrobial resistance but also to predict antibiotic resistance in silico. We now have the capability to sequence hundreds of bacterial genomes per week, including assembly and annotation. Novel and forthcoming bioinformatics tools can predict the resistome and the mobilome with a level of sophistication not previously possible. Coupled with bacterial strain collections and databases containing strain metadata, prediction of antibiotic resistance and the potential for virulence are moving rapidly toward a novel approach in molecular epidemiology. Here, we present a model system in antibiotic-resistance prediction, along with its promises and limitations. As it is commonly multidrug resistant, Pseudomonas aeruginosa causes infections that are often difficult to eradicate. We review novel approaches for genotype prediction of antibiotic resistance. We discuss the generation of microbial sequence data for real-time patient management and the prediction of antimicrobial resistance. © 2017 The Authors. Annals of the New York Academy of Sciences published by Wiley Periodicals Inc. on behalf of The New York Academy of Sciences.

  6. Antibiotic Resistance and Fungus

    Centers for Disease Control (CDC) Podcasts

    2017-02-28

    Dr. David Denning, President of the Global Action Fund for Fungal Infections and an infectious diseases clinician, discusses antimicrobial resistance and fungus.  Created: 2/28/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 2/28/2017.

  7. Supplementary Material for: Detection of antibiotic resistance in probiotics of dietary supplements

    KAUST Repository

    Wong, Aloysius Tze; Ngu, Davey; Dan, Lydia; Ooi, Amanda Siok Lee; Lim, Renee

    2015-01-01

    , streptomycin and ciprofloxacin antibiotics. Additionally, we also report a discrepancy between the enumerated viable bacteria amounts and the claims of the manufacturers. Conclusions This short report has highlighted the present of antibiotic resistance

  8. Fighting antibiotic resistance in the intensive care unit using antibiotics

    NARCIS (Netherlands)

    Plantinga, Nienke L.; Wittekamp, Bastiaan H J; Van Duijn, Pleun J.; Bonten, Marc J M

    2015-01-01

    Antibiotic resistance is a global and increasing problem that is not counterbalanced by the development of new therapeutic agents. The prevalence of antibiotic resistance is especially high in intensive care units with frequently reported outbreaks of multidrug-resistant organisms. In addition to

  9. Environmental cycle of antibiotic resistance encoded genes: A systematic review

    Directory of Open Access Journals (Sweden)

    R. ghanbari

    2017-12-01

    Full Text Available Antibiotic-resistant bacteria and genes enter the environment in different ways. The release of these factors into the environment has increased concerns related to public health. The aim of the study was to evaluate the antibiotic resistance genes (ARGs in the environmental resources. In this systematic review, the data were extracted from valid sources of information including ScienceDirect, PubMed, Google Scholar and SID. Evaluation and selection of articles were conducted on the basis of the PRISMA checklist. A total of 39 articles were included in the study, which were chosen from a total of 1249 papers. The inclusion criterion was the identification of genes encoding antibiotic resistance against the eight important groups of antibiotics determined by using the PCR technique in the environmental sources including municipal and hospital wastewater treatment plants, animal and agricultural wastes, effluents from treatment plants, natural waters, sediments, and drinking waters. In this study, 113 genes encoding antibiotic resistance to eight groups of antibiotics (beta-lactams, aminoglycosides, tetracyclines, macrolides, sulfonamides, chloramphenicol, glycopeptides and quinolones were identified in various environments. Antibiotic resistance genes were found in all the investigated environments. The investigation of microorganisms carrying these genes shows that most of the bacteria especially gram-negative bacteria are effective in the acquisition and the dissemination of these pollutants in the environment. Discharging the raw wastewaters and effluents from wastewater treatments acts as major routes in the dissemination of ARGs into environment sources and can pose hazards to public health.

  10. Detection of coliform bacteria, determination of phylogenetic typing and antibiotic resistance profile of Escherichia coli in qanats and springs of East-Azerbaijan province

    Directory of Open Access Journals (Sweden)

    N. Shabani Lokarani

    2017-05-01

    Full Text Available Escherichia coli as a fecal contamination and is considered as an index in water. The aim of this study was to determine the phenotypic and genotypic characteristics of E. coli and antibiotic resistance of the isolates collected from qanats and springs in East-Azerbaijan province. For this purpose, 118 samples were selected from above mentioned area and examined by MPN method. The positive coliform samples were identified by phenotypic and genotypic methods. Afterwards, to determine the genetic diversity of E. coli isolates, phylogenetic typing we conducted by means of multiplex PCR. To determine the antibiotic resistance profile, antibiotic discs of Nalidixic Acid, Co-trimoxazol, Amoxicillin, Gentamaicin Ciprofloxacin, Chloramphenicol, Imipenem, Cefotaxime and Ceftazidime antibiogram were used. Based on results, 48% of the samples were evaluated as positive for coliform including 40% for E. coli and 19% for Klebsiella. Amongst 23 isolates confirmed as E. coli by PCR. Phylogenetic typing revealed  that 44% of E. coli strains belonged to type D and B2 and 56% belonged to A and B1 phylotypes. Antimicrobial susceptibility pattern showed that 92% of E. coli isolates were resistant to Amoxicillin. All E. coli isolates were sensitive to Imipenem. It was concluded that presence of pathogenic E. coli with high rate of antibacterial resistance in waters source could be considered as a human health hazard.

  11. Radiation-resistant asporogenic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Yano, K [Tokyo Univ. (Japan). Faculty of Agriculture

    1975-09-01

    This paper reports the biological and ecological examinations on the radiation-resistant asporogenic bacteria (mainly concerning Micrococcus radiodurans). Radiation-resistant asporogenic bacteria were isolated from the irradiated areas of the natural world as well as from the general areas and from the Rn waters in the Misasa hot spring. The acquiring of the tolerance to radiation in bacteria was also examined. In addition, the future problems of microbiological treatment with irradiation were mentioned.

  12. Radiation-resistant asporogenic bacteria

    International Nuclear Information System (INIS)

    Yano, Keiji

    1975-01-01

    This paper reports the biological and ecological examinations on the radiation-resistant asporogenic bacteria (mainly concerning Micrococcus radiodurans). Radiation-resistant asporogenic bacteria were isolated from the irradiated areas of the natural world as well as from the general areas and from the Rn waters in the Misasa hot spring. The acquiring of the tolerance to radiation in bacteria was also examined. In addition, the future problems of microbiological treatment with irradiation were mentioned. (Tsukamoto, Y.)

  13. Reservoirs of antibiotic-resistant enterobacteriaceae among animals sympatric to humans in Senegal: extended-spectrum beta-lactamases in bacteria in a black rat (Rattus rattus)

    Czech Academy of Sciences Publication Activity Database

    Literák, I.; Dolejská, M.; Čížek, A.; Djigo, CH. A. T.; Konečný, Adam; Koubek, Petr

    2009-01-01

    Roč. 3, č. 11 (2009), s. 751-754 ISSN 1996-0808 R&D Projects: GA AV ČR IAA6093404 Institutional research plan: CEZ:AV0Z60930519 Keywords : antibiotics * resistance * Escherichia * Enterobacter * rat * Senegal Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology Impact factor: 0.407, year: 2009 http://www.academicjournals.org/ajmr/PDF/Pdf2009/Nov/Literak%20et%20al.pdf

  14. The determinants of the antibiotic resistance process

    Directory of Open Access Journals (Sweden)

    Beatriz Espinosa Franco

    2009-04-01

    Full Text Available Beatriz Espinosa Franco1, Marina Altagracia Martínez2, Martha A Sánchez Rodríguez1, Albert I Wertheimer31Facultad de Estudios Superiores Zaragoza (UNAM, Mexico; 2Universidad Autónoma Metropolitana Unidad Xochimilco, Mexico; 3Temple University, Philadelphia, Pennsylvania, USABackground: The use of antibiotic drugs triggers a complex interaction involving many biological, sociological, and psychological determinants. Resistance to antibiotics is a serious worldwide problem which is increasing and has implications for morbidity, mortality, and health care both in hospitals and in the community.Objectives: To analyze current research on the determinants of antibiotic resistance and comprehensively review the main factors in the process of resistance in order to aid our understanding and assessment of this problem.Methods: We conducted a MedLine search using the key words “determinants”, “antibiotic”, and “antibiotic resistance” to identify publications between 1995 and 2007 on the determinants of antibiotic resistance. Publications that did not address the determinants of antibiotic resistance were excluded.Results: The process and determinants of antibiotic resistance are described, beginning with the development of antibiotics, resistance and the mechanisms of resistance, sociocultural determinants of resistance, the consequences of antibiotic resistance, and alternative measures proposed to combat antibiotic resistance.Conclusions: Analysis of the published literature identified the main determinants of antibiotic resistance as irrational use of antibiotics in humans and animal species, insufficient patient education when antibiotics are prescribed, lack of guidelines for treatment and control of infections, lack of scientific information for physicians on the rational use of antibiotics, and lack of official government policy on the rational use of antibiotics in public and private hospitals.Keywords: antibiotic drug resistance

  15. The role of biofilms as environmental reservoirs of antibiotic resistance

    Directory of Open Access Journals (Sweden)

    Jose Luis eBalcazar

    2015-10-01

    Full Text Available Antibiotic resistance has become a significant and growing threat to public and environmental health. To face this problem both at local and global scales, a better understanding of the sources and mechanisms that contribute to the emergence and spread of antibiotic resistance is required. Recent studies demonstrate that aquatic ecosystems are reservoirs of resistant bacteria and antibiotic resistance genes as well as potential conduits for their transmission to human pathogens. Despite the wealth of information about antibiotic pollution and its effect on the aquatic microbial resistome, the contribution of environmental biofilms to the acquisition and spread of antibiotic resistance has not been fully explored in aquatic systems. Biofilms are structured multicellular communities embedded in a self-produced extracellular matrix that acts as a barrier to antibiotic diffusion. High population densities and proximity of cells in biofilms also increases the chances for genetic exchange among bacterial species converting biofilms in hot spots of antibiotic resistance. This review focuses on the potential effect of antibiotic pollution on biofilm microbial communities, with special emphasis on ecological and evolutionary processes underlying acquired resistance to these compounds.

  16. A model of antibiotic-resistant bacterial epidemics in hospitals

    OpenAIRE

    Webb, Glenn F.; D'Agata, Erika M. C.; Magal, Pierre; Ruan, Shigui

    2005-01-01

    The emergence of drug-resistant strains of bacteria is an increasing threat to society, especially in hospital settings. Many antibiotics that were formerly effective in combating bacterial infections in hospital patients are no longer effective because of the evolution of resistant strains, which compromises medical care worldwide. In this article, we formulate a two-level population model to quantify key elements in nosocomial (hospital-acquired) infections. At the bacteria level, patients ...

  17. Antibiotic resistance and virulence genes in coliform water isolates.

    Science.gov (United States)

    Stange, C; Sidhu, J P S; Tiehm, A; Toze, S

    2016-11-01

    Widespread fecal pollution of surface water may present a major health risk and a significant pathway for dissemination of antibiotic resistance bacteria. The River Rhine is one of the longest and most important rivers in Europe and an important raw water source for drinking water production. A total of 100 coliform isolates obtained from River Rhine (Germany) were examined for their susceptibility to seven antimicrobial agents. Resistances against amoxicillin, trimethoprim/sulfamethoxazole and tetracycline were detected in 48%, 11% and 9% of isolates respectively. The antibiotic resistance could be traced back to the resistance genes bla TEM , bla SHV , ampC, sul1, sul2, dfrA1, tet(A) and tet(B). Whereby, the ampC gene represents a special case, because its presence is not inevitably linked to a phenotypic antibiotic resistance. Multiple antibiotics resistance was often accompanied by the occurrence of class 1 or 2 integrons. E. coli isolates belonging to phylogenetic groups A and B1 (commensal) were more predominant (57%) compared to B2 and D groups (43%) which are known to carry virulent genes. Additionally, six E. coli virulence genes were also detected. However, the prevalence of virulence genes in the E. coli isolates was low (not exceeding 4.3% per gene) and no diarrheagenic E. coli pathotypes were detected. This study demonstrates that surface water is an important reservoir of ARGs for a number of antibiotic classes such as sulfonamide, trimethoprim, beta-lactam-antibiotics and tetracycline. The occurrence of antibiotic resistance in coliform bacteria isolated from River Rhine provides evidence for the need to develop management strategies to limit the spread of antibiotic resistant bacteria in aquatic environment. Copyright © 2016 Elsevier GmbH. All rights reserved.

  18. Antibiotic use and resistance in animals: Belgian initiatives.

    Science.gov (United States)

    Daeseleire, Els; De Graef, Evelyne; Rasschaert, Geertrui; De Mulder, Thijs; Van den Meersche, Tina; Van Coillie, Els; Dewulf, Jeroen; Heyndrickx, Marc

    2016-05-01

    The widespread use of antibiotics in animals is causing concerns about the growing risk for development and the spread of antibiotic-resistant bacteria. Antibiotic consumption is higher in animals than in humans as reported in a joint publication of EFSA (European Food Safety Agency), ECDC (European Centre for Disease Prevention and Control), and EMA (European Medicines Agency) using data from 2011 and 2012. Both in humans and animals, positive associations between the consumption of antibiotics and resistant bacteria are observed. Responsible use of antibiotics in humans and animals should therefore be promoted. In this paper some general aspects of antibiotic resistance such as microbiological versus clinical resistance, intrinsic versus acquired resistance, resistance mechanisms, and transfer of resistance are briefly introduced. In 2012, the Belgian Center of Expertise on Antimicrobial Consumption and Resistance in Animals (AMCRA) was founded. Its mission is to collect and analyze all data related to antibiotic use and resistance in animals in Belgium and to communicate these findings in a neutral and objective manner. One of AMCRA's 10 objectives is a 50% reduction in antibiotic consumption in veterinary medicine in Belgium by 2020. The aim of this paper is to report on the achievements of this national project. The Institute for Agricultural and Fisheries Research (ILVO, Merelbeke-Melle), in collaboration with Ghent University, is currently working on three nationally funded projects on antibiotic resistance in animal husbandry. In the first project, an in vitro model is used to study the influence of low antibiotic concentrations due to carry-over after production and usage of medicated feed on the development of resistance in the pig gut. Part of that project is to develop a quantitative risk assessment model. A second project focuses on tracking excreted antibiotics used in pig rearing and their influence on the development of antibiotic resistance in pig

  19. Antibiotics: Pharmacokinetics, toxicity, resistance and multidrug efflux pumps.

    Science.gov (United States)

    Yılmaz, Çiğdem; Özcengiz, Gülay

    2017-06-01

    The discovery of penicillin followed by streptomycin, tetracycline, cephalosporins and other natural, semi-synthetic and synthetic antimicrobials completely revolutionized medicine by reducing human morbidity and mortality from most of the common infections. However, shortly after they were introduced to clinical practice, the development of resistance was emerged. The decreasing interest from antibiotic industry in spite of rapid global emergence of antibiotic resistance is a tough dilemma from the pointview of public health. The efficiency of antimicrobial treatment is determined by both pharmacokinetics and pharmacodynamics. In spite of their selective toxicity, antibiotics still cause severe, life-threatening adverse reactions in host body mostly due to defective drug metabolism or excessive dosing regimen. The present article aims at updating current knowledge on pharmacokinetics/pharmacodynamics concepts and models, toxicity of antibiotics as well as antibiotic resistance mechanisms, resistome analyses and search for novel antibiotic resistance determinants with special emphasis given to the-state-of-the-art regarding multidrug efflux pumps and their additional physiological functions in stress adaptation and virulence of bacteria. All these issues are highly linked to each other and not only important for most efficient and prolonged use of current antibiotics, but also for discovery and development of new antibiotics and novel inhibitors of antibiotic resistance determinants of pathogens. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Probiotic approach to prevent antibiotic resistance.

    Science.gov (United States)

    Ouwehand, Arthur C; Forssten, Sofia; Hibberd, Ashley A; Lyra, Anna; Stahl, Buffy

    2016-01-01

    Probiotics are live microorganisms, mainly belonging to the genera Lactobacillus and Bifidobacterium, although also strain of other species are commercialized, that have a beneficial effect on the host. From the perspective of antibiotic use, probiotics have been observed to reduce the risk of certain infectious disease such as certain types of diarrhea and respiratory tract infection. This may be accompanied with a reduced need of antibiotics for secondary infections. Antibiotics tend to be effective against most common diseases, but increasingly resistance is being observed among pathogens. Probiotics are specifically selected to not contribute to the spread of antibiotic resistance and not carry transferable antibiotic resistance. Concomitant use of probiotics with antibiotics has been observed to reduce the incidence, duration and/or severity of antibiotic-associated diarrhea. This contributes to better adherence to the antibiotic prescription and thereby reduces the evolution of resistance. To what extent probiotics directly reduce the spread of antibiotic resistance is still much under investigation; but maintaining a balanced microbiota during antibiotic use may certainly provide opportunities for reducing the spread of resistances. Key messages Probiotics may reduce the risk for certain infectious diseases and thereby reduce the need for antibiotics. Probiotics may reduce the risk for antibiotic-associated diarrhea Probiotics do not contribute to the spread of antibiotic resistance and may even reduce it.

  1. Development of Methods for Genetic Assessment of Antibiotic Resistance In Animal Herds

    DEFF Research Database (Denmark)

    Schmidt, Gunilla Veslemøy

    with a parallel selection for resistant bacteria. Since the hazards related to antibiotic resistance development have been recognized, the prudent use of antibiotics has been in focus, especially concerning their use in animal production. For many years antibiotics have been, and still are, recklessly used...... in the animal production especially in the form of growth promoters. Due to the associated risks of resistant zoonotic bacteria transmission from animals to humans, it is of interest to keep antibiotic use and antibiotic resistance under strict surveillance.This PhD study was based on the development of real......-time PCR (qPCR) assays that supply an easy and rapid method for quantifying antibiotic resistance levels in animal herds. The pig production is accountable for a large portion of the antibiotics used for food producing animals in Denmark. Therefore, the antibiotic resistance genes included in this study...

  2. Progress in the Fight Against Multidrug-Resistant Bacteria? A Review of U.S. Food and Drug Administration-Approved Antibiotics, 2010-2015.

    Science.gov (United States)

    Deak, Dalia; Outterson, Kevin; Powers, John H; Kesselheim, Aaron S

    2016-09-06

    A weak antibiotic pipeline and the increase in drug-resistant pathogens have led to calls for more new antibiotics. Eight new antibiotics were approved by the U.S. Food and Drug Administration (FDA) between January 2010 and December 2015: ceftaroline, fidaxomicin, bedaquiline, dalbavancin, tedizolid, oritavancin, ceftolozane-tazobactam, and ceftazidime-avibactam. This study evaluates the development course and pivotal trials of these antibiotics for their innovativeness, development process, documented patient outcomes, and cost. Data sources were FDA approval packages and databases (January 2010 to December 2015); the Red Book (Truven Health Analytics); Orange Book: Approved Drug Products with Therapeutic Equivalence Evaluations (FDA); and supplementary information from company filings, press releases, and media reports. Four antibiotics were approved for acute bacterial skin and skin-structure infection. Seven had similar mechanisms of action to those of previously approved drugs. Six were initially developed by small to midsized companies, and 7 are currently marketed by 1 of 3 large companies. The drugs spent a median of 6.2 years in clinical trials (interquartile range [IQR], 5.4 to 8.8 years) and 8 months in FDA review (IQR, 7.5 to 8 months). The median number of patients enrolled in the pivotal trials was 666 (IQR, 553 to 739 patients; full range, 44 to 1005 patients), and median trial duration was 18 months (IQR, 15 to 22 months). Seven drugs were approved on the basis of pivotal trials evaluating noninferiority. One drug demonstrated superiority on an exploratory secondary end point, 2 showed decreased efficacy in patients with renal insufficiency, and 1 showed increased mortality compared with older drugs. Seven of the drugs are substantially more expensive than their trial comparators. Limitations are that future research may show benefit to patients, new drugs from older classes may show superior effectiveness in specific patient populations, and

  3. What Can Be Done about Antibiotic Resistance?

    Science.gov (United States)

    ... Us General Background: What can be done about Antibiotic Resistance? What can I do? Are antibacterial agents, such as antibacterial soaps, a solution? Are antibiotics regulated? Is there any international action on the ...

  4. Antibiotic Resistance in Human Chronic Periodontitis Microbiota

    NARCIS (Netherlands)

    Rams, Thomas E.; Degener, John E.; van Winkelhoff, Arie J.

    Background: Patients with chronic periodontitis (CP) may yield multiple species of putative periodontal bacterial pathogens that vary in their antibiotic drug susceptibility. This study determines the occurrence of in vitro antibiotic resistance among selected subgingival periodontal pathogens in

  5. Differential sensitivity of pigmented and non-pigmented marine bacteria to metals and antibiotics

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, S.; Chandramohan, D.; LokaBharathi, P.A.

    . Appl. em'ir. Microbiol. 33, 975-976. Nelson J. D. Jr and Colwell R. R. (1975) The ecology of mercury resistant bacteria in Chesapeake bay. Microbioi. Ecol. 1, 191-218. Oison B. H. and Thornton I. (1982) The resistance patterns to metals... to metals em- ploying epifluorescent microscopy. J. microbiol. Met& 7, 143-155. Zemelman R., Silva J. and Herriques, M. (1980) Antibiotic resistant bacteria in seawater from Concepcion Bay. Archs Biol. Exp. 13, 121. ...

  6. NethMap 2017: Consumption of antimicrobial agents and antimicrobial resistance among medically important bacteria in the Netherlands / MARAN 2017: Monitoring of antimicrobial resistance and antibiotic usage in animals in the Netherlands in 2016

    NARCIS (Netherlands)

    de Greeff SC; Mouton JW; ZIA; I&V

    2017-01-01

    The number of bacteria that are resistant to antimicrobials is increasing worldwide. In the Netherlands, the number of resistant bacteria that can cause infections in humans has remained broadly stable. Nevertheless there is cause for concern and caution. Compared to 2015, in 2016 more 'outbreaks'

  7. Prevalence and drug resistance in bacteria of the urinary tract ...

    African Journals Online (AJOL)

    Objective: To obtain data on the prevalence of antibiotic resistance in bacteria isolated from patients with suspected urinary tract infection in Bulawayo province, Zimbabwe. Method: Over a period of one year, 257 urine samples were analyzed for bacteria by standard procedures. Antimicrobial susceptibility testing of isolated ...

  8. The Effect of Antioxidants on Antibiotic Sensitivity of Bacteria

    OpenAIRE

    Azade ATTAR; Akif İ. QURBANOV

    2007-01-01

    Objective: The effect of different concentrations of antioxidants (ascorbic acid, emoxipin, tocopherol acetate and ionol) on antibiotic sensitivity of bacteria was studied. Method: Bacteria belong to different respiration types: Pseudomonas aeruginosa as aerobe and Escherichia coli as facultative anaerobe were used. Antibiotic sensitivity of microorganisms was determined as minimum inhibitory concentration (MIC) by dilution test. Results: Different concentrations of antioxidants increased the...

  9. Antibiotic resistance - the interplay between antibiotic use in animals and human beings

    DEFF Research Database (Denmark)

    Singer, R.S.; Finch, R.; Wegener, Henrik Caspar

    2003-01-01

    meant the problem of antibiotic resistance is fast escalating into a global health crisis. There is no doubt that misuse of these drugs in human beings has contributed to the increasing rates of resistance, but recently the use of antibiotics in food animals and its consequent effect on resistance...... levels in people has also come under scrutiny. Antimicrobials are used therapeutically and prophylactically in animals. More controversially, antimicrobials are also used as growth promoters to improve the ability of the animal to convert feed into body mass. Some argue that the impact of use....... There is a growing concern over the transmission of resistant bacteria via the food chain. Many questions will be difficult to resolve, such as how do you distinguish the fraction of resistance in human beings that originated from animals? If we wait to see evidence that a significant amount of antibiotic resistance...

  10. "Practical knowledge" and perceptions of antibiotics and antibiotic resistance among drugsellers in Tanzanian private drugstores

    Directory of Open Access Journals (Sweden)

    Tomson Göran

    2010-09-01

    Full Text Available Abstract Background Studies indicate that antibiotics are sold against regulation and without prescription in private drugstores in rural Tanzania. The objective of the study was to explore and describe antibiotics sale and dispensing practices and link it to drugseller knowledge and perceptions of antibiotics and antibiotic resistance. Methods Exit customers of private drugstores in eight districts were interviewed about the drugstore encounter and drugs bought. Drugsellers filled in a questionnaire with closed- and open-ended questions about antibiotics and resistance. Data were analyzed using mixed quantitative and qualitative methods. Results Of 350 interviewed exit customers, 24% had bought antibiotics. Thirty percent had seen a health worker before coming and almost all of these had a prescription. Antibiotics were dispensed mainly for cough, stomachache, genital complaints and diarrhea but not for malaria or headache. Dispensed drugs were assessed as relevant for the symptoms or disease presented in 83% of all cases and 51% for antibiotics specifically. Non-prescribed drugs were assessed as more relevant than the prescribed. The knowledge level of the drugseller was ranked as high or very high by 75% of the respondents. Seventy-five drugsellers from three districts participated. Seventy-nine percent stated that diseases caused by bacteria can be treated with antibiotics but 24% of these also said that antibiotics can be used for treating viral disease. Most (85% said that STI can be treated with antibiotics while 1% said the same about headache, 4% general weakness and 3% 'all diseases'. Seventy-two percent had heard of antibiotic resistance. When describing what an antibiotic is, the respondents used six different kinds of keywords. Descriptions of what antibiotic resistance is and how it occurs were quite rational from a biomedical point of view with some exceptions. They gave rise to five categories and one theme: Perceiving antibiotic

  11. Anthropogenic antibiotic resistance genes mobilization to the polar regions.

    Science.gov (United States)

    Hernández, Jorge; González-Acuña, Daniel

    2016-01-01

    Anthropogenic influences in the southern polar region have been rare, but lately microorganisms associated with humans have reached Antarctica, possibly from military bases, fishing boats, scientific expeditions, and/or ship-borne tourism. Studies of seawater in areas of human intervention and proximal to fresh penguin feces revealed the presence of Escherichia coli strains least resistant to antibiotics in penguins, whereas E. coli from seawater elsewhere showed resistance to one or more of the following antibiotics: ampicillin, tetracycline, streptomycin, and trim-sulfa. In seawater samples, bacteria were found carrying extended-spectrum β-lactamase (ESBL)-type CTX-M genes in which multilocus sequencing typing (MLST) showed different sequence types (STs), previously reported in humans. In the Arctic, on the contrary, people have been present for a long time, and the presence of antibiotic resistance genes (ARGs) appears to be much more wide-spread than was previously reported. Studies of E coli from Arctic birds (Bering Strait) revealed reduced susceptibility to antibiotics, but one globally spreading clone of E. coli genotype O25b-ST131, carrying genes of ESBL-type CTX-M, was identified. In the few years between sample collections in the same area, differences in resistance pattern were observed, with E. coli from birds showing resistance to a maximum of five different antibiotics. Presence of resistance-type ESBLs (TEM, SHV, and CTX-M) in E. coli and Klebsiella pneumoniae was also confirmed by specified PCR methods. MLST revealed that those bacteria carried STs that connect them to previously described strains in humans. In conclusion, bacteria previously related to humans could be found in relatively pristine environments, and presently human-associated, antibiotic-resistant bacteria have reached a high global level of distribution that they are now found even in the polar regions.

  12. Effects on combination of antibiotic-resistant bifidobacteria and corresponding antibiotics of survival of irradiated mice

    International Nuclear Information System (INIS)

    Korshunov, V.M.; Pinegin, B.V.; Ivanova, N.P.; Maltsev, V.N.

    1982-01-01

    Elimination of intestinal dysbacteriosis in irradiated animals by combining antibiotics and peparations of bifidobacteria resistant to these antibiotics prolonging the life of these animals was investigated. Broad spectrum antibiotics are used to treat intestinal dysbacteriosis. Bifidobacterial preparations are used to restore the microbial cenosis and their administration is started after antibiotics are discontinued. There are some flaws to deferred administration of bifidobacteria, since the process of colonization of the intestine with commercial bifidobacterial preparations is rather lengthy, and there is slow elevation of bifidobacterium level in the intestinal tract, whereas exogenous recontamination of the intestine by conditionally pathogenic bacteria is possible after antibiotic therapy is discontinued. Use of antibiotics alone could be the cause of intestinal dysbacteriosis

  13. Antibiotic resistance pattern of bacterial isolates in neonatal care unit

    Directory of Open Access Journals (Sweden)

    S Shrestha

    2010-12-01

    Full Text Available INTRODUCTION: Bacterial infections account for a huge proportion of neonatal deaths worldwide. The problem of antibiotic resistance among common bacterial pathogens mainly the gram negative bacteria is emerging globally which is of more serious concern in developing countries like Nepal. METHODS: A one year retrospective hospital based study was carried out to analyze the results of neonatal blood, cerebrospinal fluid, urine, stool and surface cultures and to look into the sensitivity pattern of the commonly used antibiotics. RESULTS: The positive yield of blood, urine, eye swab and CSF cultures were 19.56%, 38.5%, 60% and 0.36% respectively. The most common isolates in the blood culture were coagulase negative Staphylococcus, Acinetobacter, Enterobacter and non-haemolytic Streptococcus. A significant percent of the isolates were resistant to the first line antibiotics. Among the gram negative isolates more than 30% are resistant to cefotaxime and more than 50% are resistant to gentamicin. During the one year period we had Nursery outbreaks of methicillin resistant Staphylococcus aureus and Salmonella infections. With the help of environmental cultures we were able to trace the source and intervene appropriately. CONCLUSIONS: Continuous surveillance for antibiotic susceptibility, rational use of antibiotics and the strategy of antibiotic cycling can provide some answers to the emerging problem of antibiotic resistance.

  14. Antibiotic resistance pattern of bacterial isolates in neonatal care unit.

    Science.gov (United States)

    Shrestha, S; Adhikari, N; Rai, B K; Shreepaili, A

    2010-01-01

    Bacterial infections account for a huge proportion of neonatal deaths worldwide. The problem of antibiotic resistance among common bacterial pathogens mainly the gram negative bacteria is emerging globally which is of more serious concern in developing countries like Nepal. A one year retrospective hospital based study was carried out to analyze the results of neonatal blood, cerebrospinal fluid, urine, stool and surface cultures and to look into the sensitivity pattern of the commonly used antibiotics. The positive yield of blood, urine, eye swab and CSF cultures were 19.56%, 38.5%, 60% and 0.36% respectively. The most common isolates in the blood culture were coagulase negative Staphylococcus, Acinetobacter, Enterobacter and non-haemolytic Streptococcus. A significant percent of the isolates were resistant to the first line antibiotics. Among the gram negative isolates more than 30% are resistant to cefotaxime and more than 50% are resistant to gentamicin. During the one year period we had Nursery outbreaks of methicillin resistant Staphylococcus aureus and Salmonella infections. With the help of environmental cultures we were able to trace the source and intervene appropriately. Continuous surveillance for antibiotic susceptibility, rational use of antibiotics and the strategy of antibiotic cycling can provide some answers to the emerging problem of antibiotic resistance.

  15. A new antibiotic kills pathogens without detectable resistance.

    Science.gov (United States)

    Ling, Losee L; Schneider, Tanja; Peoples, Aaron J; Spoering, Amy L; Engels, Ina; Conlon, Brian P; Mueller, Anna; Schäberle, Till F; Hughes, Dallas E; Epstein, Slava; Jones, Michael; Lazarides, Linos; Steadman, Victoria A; Cohen, Douglas R; Felix, Cintia R; Fetterman, K Ashley; Millett, William P; Nitti, Anthony G; Zullo, Ashley M; Chen, Chao; Lewis, Kim

    2015-01-22

    Antibiotic resistance is spreading faster than the introduction of new compounds into clinical practice, causing a public health crisis. Most antibiotics were produced by screening soil microorganisms, but this limited resource of cultivable bacteria was overmined by the 1960s. Synthetic approaches to produce antibiotics have been unable to replace this platform. Uncultured bacteria make up approximately 99% of all species in external environments, and are an untapped source of new antibiotics. We developed several methods to grow uncultured organisms by cultivation in situ or by using specific growth factors. Here we report a new antibiotic that we term teixobactin, discovered in a screen of uncultured bacteria. Teixobactin inhibits cell wall synthesis by binding to a highly conserved motif of lipid II (precursor of peptidoglycan) and lipid III (precursor of cell wall teichoic acid). We did not obtain any mutants of Staphylococcus aureus or Mycobacterium tuberculosis resistant to teixobactin. The properties of this compound suggest a path towards developing antibiotics that are likely to avoid development of resistance.

  16. Antibiotic resistance pattern in uropathogens

    Directory of Open Access Journals (Sweden)

    Gupta V

    2002-01-01

    Full Text Available Uropathogenic strains from inpatient and outpatient departments were studied from April 1997 to March 1999 for their susceptibility profiles. The various isolates were Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, Acinetobacter baumanii and Enterococcus faecalis. Antibiotic susceptibility pattern of these isolates revealed that for outpatients, first generation cephalosporins, nitrofurantoin, norfloxacin/ciprofloxacin were effective for treatment of urinary tract infection but for inpatients, parenteral therapy with newer aminoglycosides and third generation cephalosporins need to be advocated as the organisms for nosocomial UTI exhibit a high degree of drug resistance. Trimethoprim and sulphamethoxazole combination was not found to be effective for the treatment of urinary tract infections as all the uropathogens from inpatients and outpatients showed high degree of resistance to co-trimoxazole. Culture and sensitivity of the isolates from urine samples should be done as a routine before advocating the therapy.

  17. A bacterial antibiotic-resistance gene that complements the human multidrug-resistance P-glycoprotein gene

    NARCIS (Netherlands)

    van Veen, HW; Callaghan, R; Soceneantu, L; Sardini, A; Konings, WN; Higgins, CF

    1998-01-01

    Bacteria have developed many fascinating antibiotic-resistance mechanisms(1,2). A protein in Lactococcus lactis, LmrA, mediates antibiotic resistance by extruding amphiphilic compounds from the inner leaflet of the cytoplasmic membrane(3,4). Unlike other known bacterial multidrug-resistance

  18. A Simple Model of Tetracycline Antibiotic Resistance in the Aquatic Environment (with Application to the Poudre River

    Directory of Open Access Journals (Sweden)

    Sarah Sanchez

    2011-02-01

    Full Text Available Antibiotic resistance is a major concern, yet it is unclear what causes the relatively high densities of resistant bacteria in the anthropogenically impacted environment. There are various possible scenarios (hypotheses: (A Input of resistant bacteria from wastewater and agricultural sources is significant, but they do not grow in the environment; (B Input of resistant bacteria is negligible, but the resistant bacteria (exogenous or endogenous grow due to the selection pressure of the antibiotic; (C Exogenous bacteria transfer the resistance to the endogenous bacteria and those grow. This paper presents a simple mechanistic model of tetracycline resistance in the aquatic environment. It includes state variables for tetracyclines, susceptible and resistant bacteria, and particulate and dissolved organic matter in the water column and sediment bed. The antibiotic partitions between freely dissolved, dissolved organic matter (DOM-bound and solids-bound phases, and decays. Bacteria growth is limited by DOM, inhibited by the antibiotic (susceptible bacteria only and lower due to the metabolic cost of carrying the resistance (resistant bacteria only. Resistant bacteria can transfer resistance to the susceptible bacteria (conjugation and lose the resistance (segregation. The model is applied to the Poudre River and can reproduce the major observed (literature data patterns of antibiotic concentration and resistance. The model suggests observed densities of resistant bacteria in the sediment bed cannot be explained by input (scenario A, but require growth (scenarios B or C.

  19. Increases of Antibiotic Resistance in Excessive Use of Antibiotics in Smallholder Dairy Farms in Northern Thailand

    Directory of Open Access Journals (Sweden)

    W. Suriyasathaporn

    2012-09-01

    Full Text Available Antibiotic resistance patterns of bacterial isolates from both quarter teat-tip swabs and their quarter milk samples were evaluated in smallholder dairy farms in northern Thailand with excessive use of antibiotics (HIGH compared with normal use (NORM. Results from teat-tip swab samples showed that the percentage of Bacillus spp. resistance to overall antibiotics was significantly lower in the NORM group than that of the HIGH group, whereas, the resistance percentage of coagulase-negative staphylococci in the NORM group was higher than that of the HIGH one. The overall mastitis-causing bacteria isolated from milk samples were environmental streptococci (13.8%, coagulase-negative staphylococci (9.9%, Staphylococcus aureus (5.4%, and Corynebacterium bovis (4.5%. Both staphylococci and streptococci had significantly higher percentages of resistance to cloxacillin and oxacillin in the HIGH group when compared to the NORM one. An occurrence of vancomycin-resistant bacteria was also observed in the HIGH group. In conclusion, the smallholder dairy farms with excessive use of antibiotics had a higher probability of antibiotic-resistant pattern than the farms with normal use.

  20. Marine echinoderms as reservoirs of antimicrobial resistant bacteria

    Directory of Open Access Journals (Sweden)

    Catarina Marinho

    2014-06-01

    Full Text Available Echinoderms are benthic animals that play an important ecological role in marine communities occupying diverse trophic levels in the marine food chains. The majority of echinoderms feed on small particles of edible matter, although they can eat many kinds of food (Clark, 1968. Although, some echinoderms species has been facing an emerging demand for human consumption, particularly in Asian and Mediterranean cuisine, where these animals can be eaten raw (Kelly, 2005; Micael et al., 2009. Echinoderms own an innate immune mechanism that allows them to defend themselves from high concentrations of bacteria, viruses and fungus they are often exposed, on marine sediment (Janeway and Medzhitov, 1998, Cooper, 2003. The most frequent genera of gut bacteria in echinoderms are Vibrio, Pseudomonas, Flavobacterium, and Aeromonas; nevertheless Enterococcus spp. and Escherichia coli are also present (Harris, 1993; Marinho et al., 2013. Moreover, fecal resistant bacteria found in the aquatic environment might represent an index of marine pollution (Foti et al., 2009, Kummerer, 2009. Several studies had been lead in order to identify environmental reservoirs for antibiotic-resistant bacteria in populations of fish, echinoderms and marine mammals, and they all support the thesis that these animals may serve as reservoirs since they had acquired resistant microbial species (Johnson et al., 1998, Marinho et al., 2013, Miranda and Zemelman, 2001. However, to our knowledge, there are only available in bibliography one study of antimicrobial resistant bacteria isolated from marine echinoderms (Marinho et al., 2013, which stats that their provenience in this environment is still unclear. Antimicrobial resistance outcomes from the intensive use of antimicrobial drugs in human activities associated with various mechanisms for bacteria genetic transfer (Barbosa and Levy, 2000, Coque et al., 2008. Antibiotic-resistant bacteria enter into water environments where they are

  1. Sampling and Pooling Methods for Capturing Herd Level Antibiotic Resistance in Swine Feces using qPCR and CFU Approaches

    DEFF Research Database (Denmark)

    Schmidt, Gunilla Veslemøy; Mellerup, Anders; Christiansen, Lasse Engbo

    2015-01-01

    The aim of this article was to define the sampling level and method combination that captures antibiotic resistance at pig herd level utilizing qPCR antibiotic resistance gene quantification and culture-based quantification of antibiotic resistant coliform indicator bacteria. Fourteen qPCR assays...... for commonly detected antibiotic resistance genes were developed, and used to quantify antibiotic resistance genes in total DNA from swine fecal samples that were obtained using different sampling and pooling methods. In parallel, the number of antibiotic resistant coliform indicator bacteria was determined...... in the same swine fecal samples. The results showed that the qPCR assays were capable of detecting differences in antibiotic resistance levels in individual animals that the coliform bacteria colony forming units (CFU) could not. Also, the qPCR assays more accurately quantified antibiotic resistance genes...

  2. Antibiotic and antiseptic resistance: impact on public health.

    Science.gov (United States)

    Levy, S B

    2000-10-01

    More and more we are moving patients from hospitals to homes for continued treatment. Vancomycin and triclosan were used for 30 years before any resistance emerged, because their applications were strictly limited. Today, after greatly increased use, resistance to both antibiotics and antibacterials has appeared. Of importance there are genetic links between resistance to antibiotics and to antibacterials. Health professionals and the public need to be educated about the rational use of drugs that affect the microbial world. The Alliance for the Prudent Use of Antibiotics, an international organization established in 1981 with members in more than 100 countries, has adopted education as its prime mission. Via its web site (www.apua.org) and linked information on reservoirs of antibiotic resistance (ROAR) among nonpathogenic bacteria, it reaches both providers and consumers. The message is simple: bacteria are needed for our survival. The vast majority of bacteria perform important functions that are crucial for our lives. Prudent use of both antibiotics and antibacterials must be championed to achieve and maintain the balanced microbial environment in which we have entered and evolved.

  3. Detection Antibiotic Resistance of Enviromental Bacterial Strains

    Directory of Open Access Journals (Sweden)

    Huda Zuheir Majeed

    2018-05-01

    Full Text Available      Antibiotics are randomly prescribed  for veterinary and human medication. Antibiotics by little number are used by human , animals are digested uncompletely  in their digestive system and ended up in communal sewage and hospitals, eventually discharge in environmental water sources directly with no processing.     Water itself consider as major factor of dispersal of bacteria between different environmental components. Besides, bacteria had  transferable genetic mobile elements to different sites of soil, water and humans.       Environmental swabs were collected locally including 50 swabs of hospital environment , 15 samples of poultry feces and chicken guts , 20 sample of heavy water and 15 sample of fish tank to identify16 isolate of Staphylococcus (4 isolate of Staphylococus aureus and 12 isolate of coagulase –ve Staphylococcus , 19 isolate of Enterococcus spp. , 7 isolates of Pseudomonas and 5 environment isolates for each Shigella spp.  and Salmonella spp. .           Teicoplanin and Vancomycin sensitivity test of isolates was done , showing that 2out of 16 isolates of Staphylococcus (12.5% were Vancomycin-resistant , and 3out of 19 isolates of Enterococcus (15.7 % were Vancomycin-resistant, while the rest of isolates were Vancomycin- sensitive. From other side , all isolates was Teicoplanin- sensitive except only 1 Enterococcus spp. Isolate which was intermediate . The range of the Vancomycin MIC were (6-64 µg/ml . Vancomycin resistant isolates , showed that some isolates have one plasmid band after Extraction of their DNA.

  4. Changes in Bacterial Resistance Patterns of Pediatric Urinary Tract Infections and Rationale for Empirical Antibiotic Therapy

    OpenAIRE

    İbrahim Gökçe; Neslihan Çiçek; Serçin Güven; Ülger Altuntaş; Neşe Bıyıklı; Nurdan Yıldız; Harika Alpay

    2017-01-01

    Background: The causative agent spectrum and resistance patterns of urinary tract infections in children are affected by many factors. Aims: To demonstrate antibiotic resistance in urinary tract infections and changing ratio in antibiotic resistance by years. Study Design: Retrospective cross-sectional study. Methods: We analysed antibiotic resistance patterns of isolated Gram (-) bacteria during the years 2011-2014 (study period 2) in children with urinary tract infections. We...

  5. The effect of environmental factors and migration dynamics on the prevalence of antibiotic-resistant Escherichia coli in estuary environments

    OpenAIRE

    Na, Guangshui; Lu, Zihao; Gao, Hui; Zhang, Linxiao; Li, Qianwei; Li, Ruijing; Yang, Fan; Huo, Chuanlin; Yao, Ziwei

    2018-01-01

    Understanding the antibiotic resistance transmission mechanisms and migration dynamics of antibiotic-resistant bacteria (ARB) in the natural environment is critical given the increasing prevalence of antibiotic resistance. The aim of this study was to examine the fate of sulfonamide-resistant fecal bacteria (E. coli) in an estuary ecosystem and to explore the role and contribution of environmental factors in this process. The prevalence of sulfonamide-resistance status of E. coli was analyzed...

  6. Antibiotic Application and Emergence of Multiple Antibiotic Resistance (MAR) in Global Catfish Aquaculture.

    Science.gov (United States)

    Chuah, Li-Oon; Effarizah, M E; Goni, Abatcha Mustapha; Rusul, Gulam

    2016-06-01

    Catfish is one of the most cultivated species worldwide. Antibiotics are usually used in catfish farming as therapeutic and prophylactic agents. In the USA, only oxytetracycline, a combination of sulfadimethoxine and ormetoprim, and florfenicol are approved by the Food Drug Administration for specific fish species (e.g., catfish and salmonids) and their specific diseases. Misuse of antibiotics as prophylactic agents in disease prevention, however, is common and contributes in the development of antibiotic resistance. Various studies had reported on antibiotic residues and/or resistance in farmed species, feral fish, water column, sediments, and, in a lesser content, among farm workers. Ninety percent of the world aquaculture production is carried out in developing countries, which lack regulations and enforcement on the use of antibiotics. Hence, efforts are needed to promote the development and enforcement of such a regulatory structure. Alternatives to antibiotics such as antibacterial vaccines, bacteriophages and their lysins, and probiotics have been applied to curtail the increasing emergence of antibiotic-resistant bacteria due to the imprudent application of antibiotics in aquaculture.

  7. Antibiotic tolerance and resistance in biofilms

    DEFF Research Database (Denmark)

    Ciofu, Oana; Tolker-Nielsen, Tim

    2010-01-01

    One of the most important features of microbial biofilms is their tolerance to antimicrobial agents and components of the host immune system. The difficulty of treating biofilm infections with antibiotics is a major clinical problem. Although antibiotics may decrease the number of bacteria...... in biofilms, they will not completely eradicate the bacteria in vivo which may have important clinical consequences in form of relapses of the infection....

  8. Are Sewage Treatment Plants Promoting Antibiotic Resistance?

    Science.gov (United States)

    1. Introduction 1.1. How bacteria exhibit resistance 1.1.1. Resistance to -lactams 1.1.2. Resistance to sulphonamides and trimethoprim 1.1.3. Resistance to macrolides 1.1.4. Resistance to fluoroquinolones 1.1.5. Resistance to tetracyclines 1.1.6. Resistance to nitroimidaz...

  9. Multidrug resistance in enteric and other gram-negative bacteria.

    Science.gov (United States)

    George, A M

    1996-05-15

    In Gram-negative bacteria, multidrug resistance is a term that is used to describe mechanisms of resistance by chromosomal genes that are activated by induction or mutation caused by the stress of exposure to antibiotics in natural and clinical environments. Unlike plasmid-borne resistance genes, there is no alteration or degradation of drugs or need for genetic transfer. Exposure to a single drug leads to cross-resistance to many other structurally and functionally unrelated drugs. The only mechanism identified for multidrug resistance in bacteria is drug efflux by membrane transporters, even though many of these transporters remain to be identified. The enteric bacteria exhibit mostly complex multidrug resistance systems which are often regulated by operons or regulons. The purpose of this review is to survey molecular mechanisms of multidrug resistance in enteric and other Gram-negative bacteria, and to speculate on the origins and natural physiological functions of the genes involved.

  10. Antibiotic resistance: a physicist’s view

    Science.gov (United States)

    Allen, Rosalind; Waclaw, Bartłomiej

    2016-08-01

    The problem of antibiotic resistance poses challenges across many disciplines. One such challenge is to understand the fundamental science of how antibiotics work, and how resistance to them can emerge. This is an area where physicists can make important contributions. Here, we highlight cases where this is already happening, and suggest directions for further physics involvement in antimicrobial research.

  11. The role of natural environments in the evolution of resistance traits in pathogenic bacteria

    OpenAIRE

    Martinez, Jose L.

    2009-01-01

    Antibiotics are among the most valuable compounds used for fighting human diseases. Unfortunately, pathogenic bacteria have evolved towards resistance. One important and frequently forgotten aspect of antibiotics and their resistance genes is that they evolved in non-clinical (natural) environments before the use of antibiotics by humans. Given that the biosphere is mainly formed by micro-organisms, learning the functional role of antibiotics and their resistance elements in nature has releva...

  12. Public Beliefs about Antibiotics, Infection and Resistance: A Qualitative Study

    Directory of Open Access Journals (Sweden)

    Helen Madden

    2013-11-01

    Full Text Available We aimed to gain an in-depth understanding of public views and ways of talking about antibiotics. Four focus groups were held with members of the public. In addition, 39 households were recruited and interviews, diaries of medicine taking, diaries of any contact with medication were used to explore understanding and use of medication. Discussions related to antibiotics were identified and analyzed. Participants in this study were worried about adverse effects of antibiotics, particularly for recurrent infections. Some were concerned that antibiotics upset the body’s “balance”, and many used strategies to try to prevent and treat infections without antibiotics. They rarely used military metaphors about infection (e.g., describing bacteria as invading armies but instead spoke of clearing infections. They had little understanding of the concept of antibiotic resistance but they thought that over-using antibiotics was unwise because it would reduce their future effectiveness. Previous studies tend to focus on problems such as lack of knowledge, or belief in the curative powers of antibiotics for viral illness, and neglect the concerns that people have about antibiotics, and the fact that many people try to avoid them. We suggest that these concerns about antibiotics form a resource for educating patients, for health promotion and social marketing strategies.

  13. Antibiotic usage and resistance in different regions of the Dutch community.

    NARCIS (Netherlands)

    Bruinsma, N.; Filius, P.M.; Smet, P.A.G.M. de; Degener, J.E.; Endtz, P.; Bogaard, A.E. van den; Stobberingh, E.E.

    2002-01-01

    Regional differences of antibiotic use and antibiotic resistance in the fecal indicator bacteria Escherichia coli and enterococci were determined in different cities in the south, west, and north of The Netherlands. In 1999, differences in antibiotic consumption were observed between the different

  14. Antibiotic usage and resistance in different regions of the Dutch community

    NARCIS (Netherlands)

    Bruinsma, N; Filius, PMG; De Smet, PAGM; Degener, J; Endtz, P; Van den Bogaard, AE; Stobberingh, EE

    2002-01-01

    Regional differences of antibiotic use and antibiotic resistance in the fecal indicator bacteria Escherichia coli and enterococci were determined in different cities in the south, west, and north of The Netherlands. In 1999, differences in antibiotic consumption were observed between the different

  15. Antibiotic Resistance Escherichia coli isolated from Faecal of Healthy Human

    OpenAIRE

    , S. Budiarti

    2011-01-01

    The objective of this research was to examine antibiotic resistant of Escherechia coli as intestinal normal şora, isolated from healthy human. The samples were collected from faeces of new born children, children under 3 and 5years-old, and human adult. Bacteria were isolated at Eosin Methylen Blue solid media followed by biochemistry reaction for physiological E.coli identiŞcation. Antibiotic resistant test was carried out using Kirby-Bauer method. The result showed that 95 % bacterial strai...

  16. Fate of antibiotic resistance genes within the microbial communities of three waste water treatment plants

    OpenAIRE

    Di Cesare, Andrea; Eckert, Ester; D'Urso, Silvia; Doppelbauer, Julia; Corno, Gianluca

    2016-01-01

    Although Waste Water Treatment Plant (WWTP) are designed to reduce the biological pollution of urban waters, they lack a specific action against antibiotic resistance bacteria (ARB) or antibiotic resistance genes (ARGs). Nowadays, it is well documented that WWTPs constitute a reservoir of antibiotic resistances and, in some cases, they can be a favorable environment for the selection of ARB. This represent a serious concern for the public health, because the effluents of the WWTPs can be reus...

  17. Antibiotic Resistance in Pediatric Urinary Tract Infections.

    Science.gov (United States)

    Stultz, Jeremy S; Doern, Christopher D; Godbout, Emily

    2016-12-01

    Urinary tract infections (UTIs) are a common problem in pediatric patients. Resistance to common antibiotic agents appears to be increasing over time, although resistance rates may vary based on geographic region or country. Prior antibiotic exposure is a pertinent risk factor for acquiring resistant organisms during a first UTI and recurrent UTI. Judicious prescribing of antibiotics for common pediatric conditions is needed to prevent additional resistance from occurring. Complex pediatric patients with histories of hospitalizations, prior antibiotic exposure, and recurrent UTIs are also at high risk for acquiring UTIs due to extended spectrum beta-lactamase-producing organisms. Data regarding the impact of in vitro antibiotic susceptibility testing interpretation on UTI treatment outcomes is lacking.

  18. Screening of antibiotic susceptibility to β-lactam-induced elongation of Gram-negative bacteria based on dielectrophoresis.

    Science.gov (United States)

    Chung, Cheng-Che; Cheng, I-Fang; Chen, Hung-Mo; Kan, Heng-Chuan; Yang, Wen-Horng; Chang, Hsien-Chang

    2012-04-03

    We demonstrate a rapid antibiotic susceptibility test (AST) based on the changes in dielectrophoretic (DEP) behaviors related to the β-lactam-induced elongation of Gram-negative bacteria (GNB) on a quadruple electrode array (QEA). The minimum inhibitory concentration (MIC) can be determined within 2 h by observing the changes in the positive-DEP frequency (pdf) and cell length of GNB under the cefazolin (CEZ) treatment. Escherichia coli and Klebsiella pneumoniae and the CEZ are used as the sample bacteria and antibiotic respectively. The bacteria became filamentous due to the inhibition of cell wall synthesis and cell division and cell lysis occurred for the higher antibiotic dose. According to the results, the pdfs of wild type bacteria decrease to hundreds of kHz and the cell length is more than 10 μm when the bacterial growth is inhibited by the CEZ treatment. In addition, the growth of wild type bacteria and drug resistant bacteria differ significantly. There is an obvious decrease in the number of wild type bacteria but not in the number of drug resistant bacteria. Thus, the drug resistance of GNB to β-lactam antibiotics can be rapidly assessed. Furthermore, the MIC determined using dielectrophoresis-based AST (d-AST) was consistent with the results of the broth dilution method. Utilizing this approach could reduce the time needed for bacteria growth from days to hours, help physicians to administer appropriate antibiotic dosages, and reduce the possibility of the occurrence of multidrug resistant (MDR) bacteria.

  19. Effect of radiation decontamination on drug-resistant bacteria

    International Nuclear Information System (INIS)

    Ito, Hitoshi

    2006-01-01

    More than 80% of food poisoning bacteria such as Salmonella are reported as antibiotic-resistant to at least one type antibiotic, and more than 50% as resistant to two or more. For the decontamination of food poisoning bacteria in foods, radiation resistibility on drug-resistant bacteria were investigated compared with drug-sensitive bacteria. Possibility on induction of drug-resistant mutation by radiation treatment was also investigated. For these studies, type strains of Escherichia coli S2, Salmonella enteritidis YK-2 and Staphylococcus aureus H12 were used to induce drug-resistant strains with penicillin G. From the study of radiation sensitivity on the drug-resistant strain induced from E. coli S2, D 10 value was obtained to be 0.20 kGy compared with 0.25 kGy at parent strain. On S. enteritidis YK-2, D 10 value was obtained to be 0.14 kGy at drug-resistant strain compared with 0.16 kGy at parent strain. D 10 value was also obtained to be 0.15 kGy at drug-resistant strain compared with 0.21 kGy at parent strain of St. aureus H12. Many isolates of E. coli 157:H7 or other type of E. coli from meats such as beef were resistant to penicillin G, and looked to be no relationship on radiation resistivities between drug-resistant strains and sensitive strains. On the study of radiation sensitivity on E. coli S2 at plate agars containing antibiotics, higher survival fractions were obtained at higher doses compared with normal plate agar. The reason of higher survival fractions at higher doses on plate agar containing antibiotics should be recovery of high rate of injured cells by the relay of cell division, and drug-resistant strains by mutation are hardly induced by irradiation. (author)

  20. A New Approach for the Discovery of Antibiotics by Targeting Non-Multiplying Bacteria: A Novel Topical Antibiotic for Staphylococcal Infections

    Science.gov (United States)

    Hu, Yanmin; Shamaei-Tousi, Alireza; Liu, Yingjun; Coates, Anthony

    2010-01-01

    In a clinical infection, multiplying and non-multiplying bacteria co-exist. Antibiotics kill multiplying bacteria, but they are very inefficient at killing non-multipliers which leads to slow or partial death of the total target population of microbes in an infected tissue. This prolongs the duration of therapy, increases the emergence of resistance and so contributes to the short life span of antibiotics after they reach the market. Targeting non-multiplying bacteria from the onset of an antibiotic development program is a new concept. This paper describes the proof of principle for this concept, which has resulted in the development of the first antibiotic using this approach. The antibiotic, called HT61, is a small quinolone-derived compound with a molecular mass of about 400 Daltons, and is active against non-multiplying bacteria, including methicillin sensitive and resistant, as well as Panton-Valentine leukocidin-carrying Staphylococcus aureus. It also kills mupirocin resistant MRSA. The mechanism of action of the drug is depolarisation of the cell membrane and destruction of the cell wall. The speed of kill is within two hours. In comparison to the conventional antibiotics, HT61 kills non-multiplying cells more effectively, 6 logs versus less than one log for major marketed antibiotics. HT61 kills methicillin sensitive and resistant S. aureus in the murine skin bacterial colonization and infection models. No resistant phenotype was produced during 50 serial cultures over a one year period. The antibiotic caused no adverse affects after application to the skin of minipigs. Targeting non-multiplying bacteria using this method should be able to yield many new classes of antibiotic. These antibiotics may be able to reduce the rate of emergence of resistance, shorten the duration of therapy, and reduce relapse rates. PMID:20676403

  1. [Impact of fluoroquinolone use on multidrug-resistant bacteria emergence].

    Science.gov (United States)

    Nseir, S; Ader, F; Marquette, C-H; Durocher, A

    2005-01-01

    During the last two decades, fluoroquinolone use has significantly increased in Europe and in the USA. This could be explained by the arrival of newer fluoroquinolones with antipneumoccal activity. Increased use of fluoroquinolones is associated with higher rates of bacterial resistance to these antibiotics. Resistance of Gram-negative bacilli to fluoroquinolones is increasing in industrialized countries. In addition, fluoroquinolone use has been identified as a risk factor for colonization and infection to methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumanni, extending-spectrum beta-lactamase producing Gram negative bacilli, and multidrug-resistant bacteria. Nosocomial infections due to multidrug-resistant bacteria are associated with higher mortality and morbidity rates. This could be related to more frequent inappropriate initial antibiotic treatment in these patients. Limiting the use of fluoroquinolones, limiting the duration of treatment with fluoroquinolones, and using appropriate dosage of these antibiotics could be suggested to reduce resistance to these antibiotics and to reduce the emergence of multidrug-resistant bacteria.

  2. "DRUG RESISTANCE PATTERN IN ISOLATED BACTERIA FROM BLOOD CULTURES"

    Directory of Open Access Journals (Sweden)

    A. Sobhani

    2004-05-01

    Full Text Available Bacteremia is an important infectious disease which may lead to death. Common bacteria and pattern of antibiotic resistance in different communities are different and understanding these differences is important. In the present study, relative frequency and pattern of drug resistance have been examined in bacteria isolated from blood cultures in Razi Hospital laboratory. The method of the study was descriptive. Data collection was carried out retrospectively. Total sample consisted of 311 positive blood cultures from 1999 to 2001. Variables under study were bacterial strains, antibiotics examined in antibiogram, microbial resistance, and patients' age and sex. The most common isolated bacteria were Salmonella typhi (22.2% and the least common ones were Citrobacter (1.6%. The highest antibiotic resistance was seen against amoxicillin (88.4%. The proportion of males to females was1: 1/1 and the most common age group was 15-44 (47.3%. Common bacteria and pattern of antibiotic resistance were different in some areas and this subject requires further studies in the future.

  3. Antibiotic Resistant Salmonella and Vibrio Associated with Farmed Litopenaeus vannamei

    Directory of Open Access Journals (Sweden)

    Sanjoy Banerjee

    2012-01-01

    Full Text Available Salmonella and Vibrio species were isolated and identified from Litopenaeus vannamei cultured in shrimp farms. Shrimp samples showed occurrence of 3.3% of Salmonella and 48.3% of Vibrio. The isolates were also screened for antibiotic resistance to oxolinic acid, sulphonamides, tetracycline, sulfamethoxazole/trimethoprim, norfloxacin, ampicillin, doxycycline hydrochloride, erythromycin, chloramphenicol, and nitrofurantoin. Salmonella enterica serovar Corvallis isolated from shrimp showed individual and multiple antibiotic resistance patterns. Five Vibrio species having individual and multiple antibiotic resistance were also identified. They were Vibrio cholerae (18.3%, V. mimicus (16.7%, V. parahaemolyticus (10%, V. vulnificus (6.7%, and V. alginolyticus (1.7%. Farm owners should be concerned about the presence of these pathogenic bacteria which also contributes to human health risk and should adopt best management practices for responsible aquaculture to ensure the quality of shrimp.

  4. Antibiotic Use in Agriculture and Its Consequential Resistance in Environmental Sources: Potential Public Health Implications

    Directory of Open Access Journals (Sweden)

    Christy Manyi-Loh

    2018-03-01

    Full Text Available Due to the increased demand of animal protein in developing countries, intensive farming is instigated, which results in antibiotic residues in animal-derived products, and eventually, antibiotic resistance. Antibiotic resistance is of great public health concern because the antibiotic-resistant bacteria associated with the animals may be pathogenic to humans, easily transmitted to humans via food chains, and widely disseminated in the environment via animal wastes. These may cause complicated, untreatable, and prolonged infections in humans, leading to higher healthcare cost and sometimes death. In the said countries, antibiotic resistance is so complex and difficult, due to irrational use of antibiotics both in the clinical and agriculture settings, low socioeconomic status, poor sanitation and hygienic status, as well as that zoonotic bacterial pathogens are not regularly cultured, and their resistance to commonly used antibiotics are scarcely investigated (poor surveillance systems. The challenges that follow are of local, national, regional, and international dimensions, as there are no geographic boundaries to impede the spread of antibiotic resistance. In addition, the information assembled in this study through a thorough review of published findings, emphasized the presence of antibiotics in animal-derived products and the phenomenon of multidrug resistance in environmental samples. This therefore calls for strengthening of regulations that direct antibiotic manufacture, distribution, dispensing, and prescription, hence fostering antibiotic stewardship. Joint collaboration across the world with international bodies is needed to assist the developing countries to implement good surveillance of antibiotic use and antibiotic resistance.

  5. Antibiotic Use in Agriculture and Its Consequential Resistance in Environmental Sources: Potential Public Health Implications.

    Science.gov (United States)

    Manyi-Loh, Christy; Mamphweli, Sampson; Meyer, Edson; Okoh, Anthony

    2018-03-30

    Due to the increased demand of animal protein in developing countries, intensive farming is instigated, which results in antibiotic residues in animal-derived products, and eventually, antibiotic resistance. Antibiotic resistance is of great public health concern because the antibiotic-resistant bacteria associated with the animals may be pathogenic to humans, easily transmitted to humans via food chains, and widely disseminated in the environment via animal wastes. These may cause complicated, untreatable, and prolonged infections in humans, leading to higher healthcare cost and sometimes death. In the said countries, antibiotic resistance is so complex and difficult, due to irrational use of antibiotics both in the clinical and agriculture settings, low socioeconomic status, poor sanitation and hygienic status, as well as that zoonotic bacterial pathogens are not regularly cultured, and their resistance to commonly used antibiotics are scarcely investigated (poor surveillance systems). The challenges that follow are of local, national, regional, and international dimensions, as there are no geographic boundaries to impede the spread of antibiotic resistance. In addition, the information assembled in this study through a thorough review of published findings, emphasized the presence of antibiotics in animal-derived products and the phenomenon of multidrug resistance in environmental samples. This therefore calls for strengthening of regulations that direct antibiotic manufacture, distribution, dispensing, and prescription, hence fostering antibiotic stewardship. Joint collaboration across the world with international bodies is needed to assist the developing countries to implement good surveillance of antibiotic use and antibiotic resistance.

  6. Re-sensitizing Multidrug Resistant Bacteria to Antibiotics by Targeting Bacterial Response Regulators: Characterization and Comparison of Interactions between 2-Aminoimidazoles and the Response Regulators BfmR from Acinetobacter baumannii and QseB from Francisella spp.

    Directory of Open Access Journals (Sweden)

    Morgan E. Milton

    2018-02-01

    Full Text Available 2-aminoimidazole (2-AI compounds inhibit the formation of bacterial biofilms, disperse preformed biofilms, and re-sensitize multidrug resistant bacteria to antibiotics. 2-AIs have previously been shown to interact with bacterial response regulators, but the mechanism of interaction is still unknown. Response regulators are one part of two-component systems (TCS. TCSs allow cells to respond to changes in their environment, and are used to trigger quorum sensing, virulence factors, and antibiotic resistance. Drugs that target the TCS signaling process can inhibit pathogenic behavior, making this a potent new therapeutic approach that has not yet been fully exploited. We previously laid the groundwork for the interaction of the Acinetobacter baumannii response regulator BfmR with an early 2-AI derivative. Here, we further investigate the response regulator/2-AI interaction and look at a wider library of 2-AI compounds. By combining molecular modeling with biochemical and cellular studies, we expand on a potential mechanism for interaction between response regulators and 2-AIs. We also establish that Francisella tularensis/novicida, encoding for only three known response regulators, can be a model system to study the interaction between 2-AIs and response regulators. We show that knowledge gained from studying Francisella can be applied to the more complex A. baumannii system, which contains over 50 response regulators. Understanding the impact of 2-AIs on response regulators and their mechanism of interaction will lead to the development of more potent compounds that will serve as adjuvant therapies to broad-range antibiotics.

  7. Adaptive Landscapes of Resistance Genes Change as Antibiotic Concentrations Change.

    Science.gov (United States)

    Mira, Portia M; Meza, Juan C; Nandipati, Anna; Barlow, Miriam

    2015-10-01

    Most studies on the evolution of antibiotic resistance are focused on selection for resistance at lethal antibiotic concentrations, which has allowed the detection of mutant strains that show strong phenotypic traits. However, solely focusing on lethal concentrations of antibiotics narrowly limits our perspective of antibiotic resistance evolution. New high-resolution competition assays have shown that resistant bacteria are selected at relatively low concentrations of antibiotics. This finding is important because sublethal concentrations of antibiotics are found widely in patients undergoing antibiotic therapies, and in nonmedical conditions such as wastewater treatment plants, and food and water used in agriculture and farming. To understand the impacts of sublethal concentrations on selection, we measured 30 adaptive landscapes for a set of TEM β-lactamases containing all combinations of the four amino acid substitutions that exist in TEM-50 for 15 β-lactam antibiotics at multiple concentrations. We found that there are many evolutionary pathways within this collection of landscapes that lead to nearly every TEM-genotype that we studied. While it is known that the pathways change depending on the type of β-lactam, this study demonstrates that the landscapes including fitness optima also change dramatically as the concentrations of antibiotics change. Based on these results we conclude that the presence of multiple concentrations of β-lactams in an environment result in many different adaptive landscapes through which pathways to nearly every genotype are available. Ultimately this may increase the diversity of genotypes in microbial populations. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. Antibiotic residues and resistance in the environment

    NARCIS (Netherlands)

    Pikkemaat, M.G.; Yassin, H.; Fels-Klerkx, H.J.; Berendsen, B.J.A.

    2016-01-01

    Antibiotic usage has benefited the animal industry and helped providing affordable animal proteins to the growing human population. However, since extensive use of antibiotics results in the inhibition of susceptible organisms while selecting for the resistant ones, agricultural use is contributing

  9. Electromagnetic interactions between antibiotics and bacteria

    Science.gov (United States)

    Abdul-Moqueet, Mohammad M.

    The effect of weak electromagnetic fields on the interaction of the antibiotic erythromycin on E.coli has been studied. Erythromycin is a first derivative antibiotic which is bacteriostatic in nature. E.coli's structure has been well studied and provides a baseline for understanding the interaction. Electromagnetic fields are shown to influence the growth curve of bacterium depending on the field's geometry. The theoretical model discussed in this thesis describes the interaction using a two-fluid model. The basis of this two-fluid model has been tested and shown that the concentration of antibiotics in the fluid environment is proportional to the response seen by the bacterium. The response of the bacterium has been determined using optical density measurements from which the behavior of the antibiotic-cell system has been studied.

  10. Antibiotic resistance potential of the healthy preterm infant gut microbiome

    Directory of Open Access Journals (Sweden)

    Graham Rose

    2017-01-01

    Full Text Available Background Few studies have investigated the gut microbiome of infants, fewer still preterm infants. In this study we sought to quantify and interrogate the resistome within a cohort of premature infants using shotgun metagenomic sequencing. We describe the gut microbiomes from preterm but healthy infants, characterising the taxonomic diversity identified and frequency of antibiotic resistance genes detected. Results Dominant clinically important species identified within the microbiomes included C. perfringens, K. pneumoniae and members of the Staphylococci and Enterobacter genera. Screening at the gene level we identified an average of 13 antimicrobial resistance genes per preterm infant, ranging across eight different antibiotic classes, including aminoglycosides and fluoroquinolones. Some antibiotic resistance genes were associated with clinically relevant bacteria, including the identification of mecA and high levels of Staphylococci within some infants. We were able to demonstrate that in a third of the infants the S. aureus identified was unrelated using MLST or metagenome assembly, but low abundance prevented such analysis within the remaining samples. Conclusions We found that the healthy preterm infant gut microbiomes in this study harboured a significant diversity of antibiotic resistance genes. This broad picture of resistances and the wider taxonomic diversity identified raises further caution to the use of antibiotics without consideration of the resident microbial communities.

  11. Sponge microbiota are a reservoir of functional antibiotic resistance genes

    Directory of Open Access Journals (Sweden)

    Dennis Versluis

    2016-11-01

    Full Text Available Wide application of antibiotics has contributed to the evolution of multi-drug resistant human pathogens, resulting in poorer treatment outcomes for infections. In the marine environment, seawater samples have been investigated as a resistance reservoir; however, no studies have methodically examined sponges as a reservoir of antibiotic resistance. Sponges could be important in this respect because they often contain diverse microbial communities that have the capacity to produce bioactive metabolites. Here, we applied functional metagenomics to study the presence and diversity of functional resistance genes in the sponges Aplysina aerophoba, Petrosia ficiformis and Corticium candelabrum. We obtained 37 insert sequences facilitating resistance to D-cycloserine (n=6, gentamicin (n=1, amikacin (n=7, trimethoprim (n=17, chloramphenicol (n=1, rifampicin (n=2 and ampicillin (n=3. Fifteen of 37 inserts harboured resistance genes that shared <90% amino acid identity with known gene products, whereas on 13 inserts no resistance gene could be identified with high confidence, in which case we predicted resistance to be mainly mediated by antibiotic efflux. One marine-specific ampicillin-resistance-conferring β-lactamase was identified in the genus Pseudovibrio with 41% global amino acid identity to the closest β-lactamase with demonstrated functionality, and subsequently classified into a new family termed PSV. Taken together, our results show that sponge microbiota host diverse and novel resistance genes that may be harnessed by phylogenetically distinct bacteria.

  12. Synergistic antimicrobial therapy using nanoparticles and antibiotics for the treatment of multidrug-resistant bacterial infection

    Science.gov (United States)

    Gupta, Akash; Saleh, Neveen M.; Das, Riddha; Landis, Ryan F.; Bigdeli, Arafeh; Motamedchaboki, Khatereh; Rosa Campos, Alexandre; Pomeroy, Kenneth; Mahmoudi, Morteza; Rotello, Vincent M.

    2017-06-01

    Infections caused by multidrug-resistant (MDR) bacteria pose a serious global burden of mortality, causing thousands of deaths each year. Antibiotic treatment of resistant infections further contributes to the rapidly increasing number of antibiotic-resistant species and strains. Synthetic macromolecules such as nanoparticles (NPs) exhibit broad-spectrum activity against MDR species, however lack of specificity towards bacteria relative to their mammalian hosts limits their widespread therapeutic application. Here, we demonstrate synergistic antimicrobial therapy using hydrophobically functionalized NPs and fluoroquinolone antibiotics for treatment of MDR bacterial strains. An 8-16-fold decrease in antibiotic dosage is achieved in presence of engineered NPs to combat MDR strains. This strategy demonstrates the potential of using NPs to ‘revive’ antibiotics that have been rendered ineffective due to the development of resistance by pathogenic bacteria.

  13. Antibacterial activity of plant extracts and phytochemicals on antibiotic-resistant bacteria Atividade de extratos vegetais e fitofármacos sobre bactérias resistentes a antibióticos

    Directory of Open Access Journals (Sweden)

    Gislene G. F. Nascimento

    2000-10-01

    Full Text Available The antimicrobial activity of plant extracts and phytochemicals was evaluated with antibiotic susceptible and resistant microorganisms. In addition, the possible synergistic effects when associated with antibiotics were studied. Extracts from the following plants were utilized: Achillea millifolium (yarrow, Caryophyllus aromaticus (clove, Melissa offficinalis (lemon-balm, Ocimun basilucum (basil, Psidium guajava (guava, Punica granatum (pomegranate, Rosmarinus officinalis (rosemary, Salvia officinalis (sage, Syzygyum joabolanum (jambolan and Thymus vulgaris (thyme. The phytochemicals benzoic acid, cinnamic acid, eugenol and farnesol were also utilized. The highest antimicrobial potentials were observed for the extracts of Caryophyllus aromaticus and Syzygyum joabolanum, which inhibited 64.2 and 57.1% of the tested microorganisms, respectively, with higher activity against antibiotic-resistant bacteria (83.3%. Sage and yarrow extracts did not present any antimicrobial activity. Association of antibiotics and plant extracts showed synergistic antibacterial activity against antibiotic-resistant bacteria. The results obtained with Pseudomonas aeruginosa was particularly interesting, since it was inhibited by clove, jambolan, pomegranate and thyme extracts. This inhibition was observed with the individual extracts and when they were used in lower concentrations with ineffective antibiotics.Foi avaliada a atividade antimicrobiana de extratos vegetais e fitofármacos frente a microrganismos sensíveis e resistentes a antibióticos, bem como observado o possível efeito sinérgico da associação entre antibióticos e extratos vegetais. Foram utilizados os extratos de plantas cujo nomes populares são: tomilho, alecrim, cravo-da-Índia, jambolão, erva cidreira, romã, goiaba, sálvia, manjericão e mil-folhas, e ainda os fitofármacos, ácido benzóico, ácido cinâmico, eugenol e farnesol. Na avaliação da atividade antimicrobiana através do m

  14. Antibiotic Resistance: MedlinePlus Health Topic

    Science.gov (United States)

    ... GO GO About MedlinePlus Site Map FAQs Customer Support Health Topics Drugs & Supplements Videos & Tools Español You Are Here: Home → Health Topics → Antibiotic Resistance URL of this page: https://medlineplus.gov/antibioticresistance. ...

  15. Antibiotic resistance and pathogenicity factors in Staphylococcus ...

    Indian Academy of Sciences (India)

    know which endemic strains of S. aureus in dairy cattle ... Antibiotic resistance; cattle; mastitis; MRSA; pathogenic genes ... recommended by Clinical and Laboratory Standards Institute ...... fnbA, eno, hla and nuc, did not show any relation to.

  16. Transfer of Antibiotic Resistance in Staphylococcus aureus

    DEFF Research Database (Denmark)

    Haaber, Jakob; Penadés, José R; Ingmer, Hanne

    2017-01-01

    Staphylococcus aureus is a serious human pathogen with remarkable adaptive powers. Antibiotic-resistant clones rapidly emerge mainly by acquisition of antibiotic-resistance genes from other S. aureus strains or even from other genera. Transfer is mediated by a diverse complement of mobile genetic...... of plasmids that can be transferred by conjugation and the efficiency with which transduction occurs. Here, we review the main routes of antibiotic resistance gene transfer in S. aureus in the context of its biology as a human commensal and a life-threatening pathogen. Staphylococcus aureus cells...... are effective in exchanging mobile genetic elements, including antibiotic-resistance genes.During colonization or infection of host organisms, the exchange appears to be particularly effective.Bacteriophage-mediated transfer involves both transduction and autotransduction, which may enable lysogenic S. aureus...

  17. Effects of combination of antibiotic-resistant bifidobacteria and corresponding antibiotics on survival of irradiated mice

    Energy Technology Data Exchange (ETDEWEB)

    Korshunov, V.M.; Pinegin, B.V.; Ivanova, N.P.; Mal' tsev, V.N.

    1982-05-01

    Broad-spectrum antibiotics are used to treat intestinal dysbacteriosis of diverse etiology, including postradiation dysbacteriosis. Antibiotic therapy is instrumental in decontaminating the intestine. In addition to pathogenic microorganisms, there is disappearance of lactobacilli and bifidobacteria which perform several important and useful functions. For this reason, in addition to antibiotics, bifidobacterial preparations are used to restore the microbial cenosis and administration thereof is started after antibiotics are discontinued. There are some flaws to deferred administration of bifidobacteria, since the process of colonization of the intestine with commercial bifidobacterial preparations is rather lengthy, and there is slow elevation of bididobacterium level in the intestinal tract, whereas exogenous recontamination of the intestine by conditionally pathogenic bacteria is possible after antibiotic therapy is discontinued. On the other hand, use of antibiotics alone could, in turn, be the cause of intestinal dysbacteriosis. Our objective was to eliminate intestinal dysbacteriosis in irradiated animals by means of combining antibiotics and preparations of bifidobacteria resistant to these antibiotics, and thus prolong the life of these animals.

  18. Management Options For Reducing The Release Of Antibiotics And Antibiotic Resistance Genes To The Environment

    Science.gov (United States)

    Background: There is growing concern worldwide about the role of polluted soil and water - 77 environments in the development and dissemination of antibiotic resistance. 78 Objective: To identify management options for reducing the spread of antibiotics and 79 antibiotic resist...

  19. Sulfonamide-Resistant Bacteria and Their Resistance Genes in Soils Fertilized with Manures from Jiangsu Province, Southeastern China

    OpenAIRE

    Wang, Na; Yang, Xiaohong; Jiao, Shaojun; Zhang, Jun; Ye, Boping; Gao, Shixiang

    2014-01-01

    Antibiotic-resistant bacteria and genes are recognized as new environmental pollutants that warrant special concern. There were few reports on veterinary antibiotic-resistant bacteria and genes in China. This work systematically analyzed the prevalence and distribution of sulfonamide resistance genes in soils from the environments around poultry and livestock farms in Jiangsu Province, Southeastern China. The results showed that the animal manure application made the spread and abundance of a...

  20. Antibiotic resistance in stream: monitoring, modeling and effluent control by photocatalytic disinfection

    OpenAIRE

    Antonio, Fiorentino

    2015-01-01

    2013-2014 Since the 1940s, the ever-increasing use of antibiotics for human, veterinary and agricultural purposes, contributes to their continuous release into the environment due to incomplete metabolism or due to disposal of unused antibiotics. The concern for the release of antibiotics into the environment isrelated to the development of antibiotic resistance genes (ARGs) and bacteria (ARB), which reduce the therapeutic potential against human and animal pathogens. Urban wastewater trea...

  1. Rapid determination of antibiotic resistance in E. coli using dielectrophoresis

    International Nuclear Information System (INIS)

    Hoettges, Kai F; Dale, Jeremy W; Hughes, Michael P

    2007-01-01

    In recent years, infections due to antibiotic-resistant strains of bacteria such as methillicin-resistant Staphylococcus aureus and ciprofloxacin-resistant Escherichia coli are on the rise, and with them the demand for rapid antibiotic testing is also rising. Conventional tests, such as disc diffusion testing, require a primary sample to be tested in the presence of a number of antibiotics to verify which antibiotics suppress growth, which take approximately 24 h to complete and potentially place the patient at severe risk. In this paper we describe the use of dielectrophoresis as a rapid marker of cell death, by detecting changes in the electrophysiology of the cell caused by the administration of an antibiotic. In contrast to other markers, the electrophysiology of the cell changes rapidly during cell death allowing live cells to be distinguished from dead (or dying) cells without the need for culturing. Using polymyxin B as an example antibiotic, our studies indicate that significant changes in cell characteristics can be observed as soon as 1 h passes after isolating a culture from nutrient broth

  2. Antibiotic effects against periodontal bacteria in organ cultured tissue.

    Science.gov (United States)

    Takeshita, Masaaki; Haraguchi, Akira; Miura, Mayumi; Hamachi, Takafumi; Fukuda, Takao; Sanui, Terukazu; Takano, Aiko; Nishimura, Fusanori

    2017-02-01

    Mechanical reduction of infectious bacteria by using physical instruments is considered the principal therapeutic strategy for periodontal disease; addition of antibiotics is adjunctive. However, local antibiotic treatment, combined with conventional mechanical debridement, has recently been shown to be more effective in periodontitis subjects with type 2 diabetes. This suggests that some bacteria may invade the inflamed inner gingival epithelium, and mechanical debridement alone will be unable to reduce these bacteria completely. Therefore, we tried to establish infected organ culture models that mimic the inner gingival epithelium and aimed to see the effects of antibiotics in these established models. Mouse dorsal skin epithelia were isolated, and periodontal bacteria were injected into the epithelia. Infected epithelia were incubated with test antibiotics, and colony-forming ability was evaluated. Results indicated that effective antibiotics differed according to injected bacteria and the bacterial combinations tested. Overall, in organ culture model, the combination of amoxicillin or cefdinir and metronidazole compensate for the effects of less effective bacterial combinations on each other. This in vitro study would suggest effective periodontal treatment regimens, especially for severe periodontitis.

  3. Pharmaceutical Approaches to Target Antibiotic Resistance Mechanisms.

    Science.gov (United States)

    Schillaci, Domenico; Spanò, Virginia; Parrino, Barbara; Carbone, Anna; Montalbano, Alessandra; Barraja, Paola; Diana, Patrizia; Cirrincione, Girolamo; Cascioferro, Stella

    2017-10-26

    There is urgent need for new therapeutic strategies to fight the global threat of antibiotic resistance. The focus of this Perspective is on chemical agents that target the most common mechanisms of antibiotic resistance such as enzymatic inactivation of antibiotics, changes in cell permeability, and induction/activation of efflux pumps. Here we assess the current landscape and challenges in the treatment of antibiotic resistance mechanisms at both bacterial cell and community levels. We also discuss the potential clinical application of chemical inhibitors of antibiotic resistance mechanisms as add-on treatments for serious drug-resistant infections. Enzymatic inhibitors, such as the derivatives of the β-lactamase inhibitor avibactam, are closer to the clinic than other molecules. For example, MK-7655, in combination with imipenem, is in clinical development for the treatment of infections caused by carbapenem-resistant Enterobacteriaceae and Pseudomonas aeruginosa, which are difficult to treat. In addition, other molecules targeting multidrug-resistance mechanisms, such as efflux pumps, are under development and hold promise for the treatment of multidrug resistant infections.

  4. Bactericidal effect of bovine lactoferrin, LFcin, LFampin and LFchimera on antibiotic-resistant Staphylococcus aureus and Escherichia coli

    NARCIS (Netherlands)

    Flores-Villaseñor, H.; Canizalez-Román, A.; Reyes-Lopez, M.; Nazmi, K.; de la Garza, M.; Zazueta-Beltrán, J.; León-Sicairos, N.; Bolscher, J.G.M.

    2010-01-01

    Increased prevalence of antibiotic-resistant bacteria has become a major threat to the health sector worldwide due to their virulence, limited therapeutic options and distribution in both hospital and community settings. Discovery and development of new agents to combat antibiotic-resistant bacteria

  5. Association of Antibiotic Resistance in Agricultural Escherichia coli Isolates with Attachment to Quartz▿

    OpenAIRE

    Liu, Ping; Soupir, Michelle L.; Zwonitzer, Martha; Huss, Bridgette; Jarboe, Laura R.

    2011-01-01

    Surface water can be contaminated by bacteria from various sources, including manure from agricultural facilities. Attachment of these bacteria to soil and organic particles contributes to their transport through the environment, though the mechanism of attachment is unknown. As bacterial attachment to human tissues is known to be correlated with antibiotic resistance, we have investigated here the relationship between bacterial attachment to environmental particles and antibiotic resistance ...

  6. Functional characterization of the antibiotic resistance reservoir in the human microflora

    DEFF Research Database (Denmark)

    Sommer, Morten; Church, George M; Dantas, Gautam

    2010-01-01

    The increasing levels of multi-drug resistance in human pathogenic bacteria are compromising our ability to treat infectious disease. Since antibiotic resistance determinants are readily exchanged between bacteria through lateral gene transfer, there is an increasing interest in investigating res...

  7. Antibiotics

    Science.gov (United States)

    Antibiotics are powerful medicines that fight bacterial infections. Used properly, antibiotics can save lives. They either kill bacteria or ... natural defenses can usually take it from there. Antibiotics do not fight infections caused by viruses, such ...

  8. Impact of anthropogenic activities on the dissemination of antibiotic resistance across ecological boundaries.

    Science.gov (United States)

    Tripathi, Vijay; Cytryn, Eddie

    2017-02-28

    Antibiotics are considered to be one of the major medical breakthroughs in history. Nonetheless, over the past four decades, antibiotic resistance has reached alarming levels worldwide and this trend is expected to continue to increase, leading some experts to forecast the coming of a 'post-antibiotic' era. Although antibiotic resistance in pathogens is traditionally linked to clinical environments, there is a rising concern that the global propagation of antibiotic resistance is also associated with environmental reservoirs that are linked to anthropogenic activities such as animal husbandry, agronomic practices and wastewater treatment. It is hypothesized that the emergence and dissemination of antibiotic-resistant bacteria (ARB) and antibiotic-resistant genes (ARGs) within and between environmental microbial communities can ultimately contribute to the acquisition of antibiotic resistance in human pathogens. Nonetheless, the scope of this phenomenon is not clear due to the complexity of microbial communities in the environment and methodological constraints that limit comprehensive in situ evaluation of microbial genomes. This review summarizes the current state of knowledge regarding antibiotic resistance in non-clinical environments, specifically focusing on the dissemination of antibiotic resistance across ecological boundaries and the contribution of this phenomenon to global antibiotic resistance. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  9. An underappreciated hotspot of antibiotic resistance

    DEFF Research Database (Denmark)

    Chen, Qing-Lin; Li, Hu; Zhou, Xin-Yuan

    2017-01-01

    Landfills are so far the most common practice for the disposals of municipal solid waste (MSW) worldwide. Since MSW landfill receives miscellaneous wastes, including unused/expired antibiotics and bioactive wastes, it gradually becomes a huge potential bioreactor for breeding antibiotic resistance....... Antibiotic resistance genes (ARGs) in landfill can flow to the environment through leakage of landfill leachate and pose a risk to public health. Using high throughput quantitative Polymerase Chain Reaction (HT-qPCR), we investigated the prevalence, diversity of ARGs and its association with various mobile...... be the potential hosts of ARGs. These findings provide evidence that groundwater near MSW landfill is an underappreciated hotspot of antibiotic resistance and contribute to the spread of ARGs via the flowing contaminated groundwater....

  10. Human health risk assessment (HHRA) for environmental development and transfer of antibiotic resistance

    DEFF Research Database (Denmark)

    Ashbolt, Nicholas J.; Amézquita, Alejandro; Backhaus, Thomas

    2013-01-01

    to enable human health risk assessments (HHRA) that focus on the role of the environment in the failure of antibiotic treatment caused by antibiotic-resistant pathogens. Methods: The authors participated in a workshop held 4-8 March 2012 in Québec, Canada, to define the scope and objectives...... of an environmental assessment of antibiotic-resistance risks to human health. We focused on key elements of environmental-resistance-development "hot spots," exposure assessment (unrelated to food), and dose response to characterize risks that may improve antibiotic-resistance management options. Discussion: Various...... novel aspects to traditional risk assessments were identified to enable an assessment of environmental antibiotic resistance. These include a) accounting for an added selective pressure on the environmental resistome that, over time, allows for development of antibiotic-resistant bacteria (ARB); b...

  11. Tracking Change: A Look at the Ecological Footprint of Antibiotics and Antimicrobial Resistance

    Directory of Open Access Journals (Sweden)

    David M. Patrick

    2013-03-01

    Full Text Available Among the class of pollutants considered as ‘emerging contaminants’, antibiotic compounds including drugs used in medical therapy, biocides and disinfectants merit special consideration because their bioactivity in the environment is the result of their functional design. Antibiotics can alter the structure and function of microbial communities in the receiving environment and facilitate the development and spread of resistance in critical species of bacteria including pathogens. Methanogenesis, nitrogen transformation and sulphate reduction are among the key ecosystem processes performed by bacteria in nature that can also be affected by the impacts of environmental contamination by antibiotics. Together, the effects of the development of resistance in bacteria involved in maintaining overall ecosystem health and the development of resistance in human, animal and fish pathogens, make serious contributions to the risks associated with environmental pollution by antibiotics. In this brief review, we discuss the multiple impacts on human and ecosystem health of environmental contamination by antibiotic compounds.

  12. Lytic phages obscure the cost of antibiotic resistance in Escherichia coli.

    Science.gov (United States)

    Tazzyman, Samuel J; Hall, Alex R

    2015-03-17

    The long-term persistence of antibiotic-resistant bacteria depends on their fitness relative to other genotypes in the absence of drugs. Outside the laboratory, viruses that parasitize bacteria (phages) are ubiquitous, but costs of antibiotic resistance are typically studied in phage-free experimental conditions. We used a mathematical model and experiments with Escherichia coli to show that lytic phages strongly affect the incidence of antibiotic resistance in drug-free conditions. Under phage parasitism, the likelihood that antibiotic-resistant genetic backgrounds spread depends on their initial frequency, mutation rate and intrinsic growth rate relative to drug-susceptible genotypes, because these parameters determine relative rates of phage-resistance evolution on different genetic backgrounds. Moreover, the average cost of antibiotic resistance in terms of intrinsic growth in the antibiotic-free experimental environment was small relative to the benefits of an increased mutation rate in the presence of phages. This is consistent with our theoretical work indicating that, under phage selection, typical costs of antibiotic resistance can be outweighed by realistic increases in mutability if drug resistance and hypermutability are genetically linked, as is frequently observed in clinical isolates. This suggests the long-term distribution of antibiotic resistance depends on the relative rates at which different lineages adapt to other types of selection, which in the case of phage parasitism is probably extremely common, as well as costs of resistance inferred by classical in vitro methods.

  13. Resistance to the tetracyclines and macrolide-lincosamide-streptogramin group of antibiotics and its genetic linkage – a review

    Directory of Open Access Journals (Sweden)

    Durdica Marosevic

    2017-06-01

    Full Text Available An excessive use of antimicrobial agents poses a risk for the selection of resistant bacteria. Of particular interest are antibiotics that have large consumption rates in both veterinary and human medicine, such as the tetracyclines and macrolide-lincosamide-streptogramin (MLS group of antibiotics. A high load of these agents increases the risk of transmission of resistant bacteria and/or resistance determinants to humans, leading to a subsequent therapeutic failure. An increasing incidence of bacteria resistant to both tetracyclines and MLS antibiotics has been recently observed. This review summarizes the current knowledge on different tetracycline and MLS resistance genes that can be linked together on transposable elements.

  14. Changing Priorities in Vaccinology: Antibiotic Resistance Moving to the Top

    Directory of Open Access Journals (Sweden)

    Aldo Tagliabue

    2018-05-01

    Full Text Available Antimicrobial resistance (AMR is currently the most alarming issue for human health. AMR already causes 700,000 deaths/year. It is estimated that 10 million deaths due to AMR will occur every year after 2050. This equals the number of people dying of cancer every year in present times. International institutions such as G20, World Bank, World Health Organization (WHO, UN General Assembly, European Union, and the UK and USA governments are calling for new antibiotics. To underline this emergency, a list of antibiotic-resistant “priority pathogens” has been published by WHO. It contains 12 families of bacteria that represent the greatest danger for human health. Resistance to multiple antibiotics is particularly relevant for the Gram-negative bacteria present in the list. The ability of these bacteria to develop mechanisms to resist treatment could be transmitted with genetic material, allowing other bacteria to become drug resistant. Although the search for new antimicrobial drugs remains a top priority, the pipeline for new antibiotics is not promising, and alternative solutions are needed. A possible answer to AMR is vaccination. In fact, while antibiotic resistance emerges rapidly, vaccines can lead to a much longer lasting control of infections. New technologies, such as the high-throughput cloning of human B cells from convalescent or vaccinated people, allow for finding new protective antigens (Ags that could not be identified with conventional technologies. Antibodies produced by convalescent B cell clones can be screened for their ability to bind, block, and kill bacteria, using novel high-throughput microscopy platforms that rapidly capture digital images, or by conventional technologies such as bactericidal, opsono-phagocytosis and FACS assays. Selected antibodies expressed by recombinant DNA techniques can be used for passive immunization in animal models and tested for protection. Antibodies providing the best protection can be

  15. Antibiotics resistance of Stenotrophomonas maltophilia strains ...

    African Journals Online (AJOL)

    Background: A limited number of antibiotics are recommended for the therapy of Stenotrophomonas maltophilia infections due to therapy difficulties caused by its numerous mechanisms of resistance. Objectives: In this study conducted over a period of approximately 5 years we aimed to determine resistance rates of S.

  16. Prevalence of nasopharyngeal antibiotic-Resistant pneumococcal ...

    African Journals Online (AJOL)

    Conclusion: Pneumococcal resistance was significant in this group of children with easy access to paediatric services and antibiotic use. The implication of such high resistance for the treatment of pneumococcal diseases is that high-dose amoxicillin is the preferred empirical oral therapy for treatment of otitis media.

  17. Appendectomy as a Risk Factor for Bacteremic Biliary Tract Infection Caused by Antibiotic-Resistant Pathogens

    Directory of Open Access Journals (Sweden)

    Koki Kawanishi

    2017-01-01

    Full Text Available Background/Aims. Recent evidence has suggested that appendix plays a pivotal role in the development and preservation of intestinal immune system. The aim of this study is to examine whether prior appendectomy is associated with an increased risk for the development of antibiotic-resistant bacteria in bacteremia from biliary tract infection (BTI. Methods. Charts from 174 consecutive cases of bacteremia derived from BTI were retrospectively reviewed. Using multivariate analysis, independent risk factors for development of antibiotic-resistant bacteria were identified among the clinical parameters, including a history of appendectomy. Results. In total, 221 bacteria strains were identified from 174 BTI events. Of those, 42 antibiotic-resistant bacteria were identified in 34 patients. Multivariate analysis revealed that prior appendectomy (Odds ratio (OR, 3.02; 95% confidence interval (CI, 1.15–7.87; p=0.026, antibiotic use within the preceding three months (OR, 3.06; 95% CI, 1.26–7.64; p=0.013, and bilioenteric anastomosis or sphincterotomy (OR, 3.77; 95% CI, 1.51–9.66; p=0.0046 were independent risk factors for antibiotic-resistant bacteria. Conclusions. Prior appendectomy was an independent risk factor for the development of antibiotic-resistant bacteria in bacteremia from BTI.

  18. Systemic resistance induced by rhizosphere bacteria

    NARCIS (Netherlands)

    Loon, L.C. van; Bakker, P.A.H.M.; Pieterse, C.M.J.

    1998-01-01

    Nonpathogenic rhizobacteria can induce a systemic resistance in plants that is phenotypically similar to pathogen-induced systemic acquired resistance (SAR). Rhizobacteria-mediated induced systemic resistance (ISR) has been demonstrated against fungi, bacteria, and viruses in Arabidopsis, bean,

  19. Induction of bacterial antibiotic resistance by mutagenic halogenated nitrogenous disinfection byproducts

    International Nuclear Information System (INIS)

    Lv, Lu; Yu, Xin; Xu, Qian; Ye, Chengsong

    2015-01-01

    Halogenated nitrogenous disinfection byproducts (N-DBPs) raise concerns regarding their mutagenicity and carcinogenicity threatening public health. However, environmental consequence of their mutagenicity has received less attention. In this study, the effect of halogenated N-DBPs on bacterial antibiotic resistance (BAR) was investigated. After exposure to bromoacetamide (BAcAm), trichloroacetonitrile (TCAN) or tribromonitromethane (TBNM), the resistance of Pseudomonas aeruginosa PAO1 to both individual and multiple antibiotics (ciprofloxacin, gentamicin, polymyxin B, rifampin, tetracycline, ciprofloxacin + gentamicin and ciprofloxacin + tetracycline) was increased, which was predominantly ascribed to the overexpression of efflux pumps. The mechanism of this effect was demonstrated to be mutagenesis through sequencing and analyzing antibiotic resistance genes. The same induction phenomena also appeared in Escherichia coli, suggesting this effect may be universal to waterborne pathogens. Therefore, more attention should be given to halogenated N-DBPs, as they could increase not only genotoxicological risks but also epidemiological risks of drinking water. - Highlights: • The halogenated N-DBPs could induce bacterial antibiotic resistance. • Both individual and multiple resistances could be induced. • Efflux mechanism played an important role in the induced antibiotic resistance. • The halogenated N-DBPs induced bacterial antibiotic resistance via mutagenesis. • Effects of N-DBPs on antibiotic resistance may be universal to waterborne pathogens. - Halogenated N-DBPs could increase antibiotic resistance, even multidrug resistance via mutagenesis, contributing to the enrichment of antibiotic resistant bacteria in drinking water

  20. Antibiotic Resistance and the Biology of History.

    Science.gov (United States)

    Landecker, Hannah

    2016-12-01

    Beginning in the 1940s, mass production of antibiotics involved the industrial-scale growth of microorganisms to harvest their metabolic products. Unfortunately, the use of antibiotics selects for resistance at answering scale. The turn to the study of antibiotic resistance in microbiology and medicine is examined, focusing on the realization that individual therapies targeted at single pathogens in individual bodies are environmental events affecting bacterial evolution far beyond bodies. In turning to biological manifestations of antibiotic use, sciences fathom material outcomes of their own previous concepts. Archival work with stored soil and clinical samples produces a record described here as 'the biology of history': the physical registration of human history in bacterial life. This account thus foregrounds the importance of understanding both the materiality of history and the historicity of matter in theories and concepts of life today.

  1. The transport of antibiotic resistance genes and residues in groundwater near swine production facilities

    Science.gov (United States)

    Lin, Y. F.; Yannarell, A. C.; Mackie, R. I.; Krapac, I. G.; Chee-Sanford, J. S.; Koike, S.

    2008-12-01

    The use of antibiotics at concentrated animal feeding operations (CAFOs) for disease prevention, disease treatment, and growth promotion can contribute to the spread of antibiotic compounds, their breakdown products, and antibiotic resistant bacteria and/or the genes that confer resistance. In addition, constitutive use of antibiotics at sub-therapeutic levels can select for antibiotic resistance among the bacteria that inhabit animal intestinal tracts, onsite manure treatment facilities, and any environments receiving significant inputs of manure (e.g. through waste lagoon leakage or fertilizer amendments to farm soils). If the antibiotic resistant organisms persist in these new environments, or if they participate in genetic exchanges with the native microflora, then CAFOs may constitute a significant reservoir for the spread of antibiotic resistance to the environment at large. Our results have demonstrated that leakage from waste treatment lagoons can influence the presence and persistence of tetracycline resistance genes in the shallow aquifer adjacent to swine CAFOs, and molecular phylogeny allowed us to distinguish "native" tetracycline resistance genes in control groundwater wells from manure-associated genes introduced from the lagoon. We have also been able to detect the presence of erythromycin resistance genes in CAFO surface and groundwater even though erythromycin is strictly reserved for use in humans and thus is not utilized at any of these sites. Ongoing research, including modeling of particle transport in groundwater, will help to determine the potential spatial and temporal extent of CAFO-derived antibiotic resistance.

  2. Antibiotic Resistance in Childhood with Pneumococcal Infection

    Directory of Open Access Journals (Sweden)

    Ali Gunes

    2013-10-01

    Full Text Available Aim: Resistance to antibiotics is better. Between should not be in capitals. Antibiotics resistant has been increasing in pneumococci that cause serious diseases such as pneumonia, meningitis in recent years. The resistance rates vary between geographic regions. In this study, we aimed to determine antibiotic resistance rates in pneumococcal infections in our region. Material and Method: This study included 31 pneumococcal strains isolated from blood, CSF and urine samples of patients with meningitis, sepsis and urinary tract infections who admitted Dicle University Medicine School Children Clinic and Diyarbakir Pediatric Hospital Between December 2004-April 2007. Reproducing clinical specimens with alpha-hemolysis, optochin-sensitive, bile soluble and gram-positive diplococci morphology was defined as S. pneumoniae. The antimicrobial susceptibilities of strains were measured by the E-test method. MIC values of penicillin against pneumococci was accepted as <0.06 mg / ml value of the sensitive, 0.12-1μg/ml mid-level resistance, ≥ 2 mg / ml value of the high-level resistance. Results: It was found 16% mid-level penicillin resistance and 3.2% high-level penicillin resistance by E-test method. 80.7% of Strains were percent of the penicillin-sensitive. Seftiriakson resistance was found as 3.2%. there was not Vancomycin resistance. Discussion: We think penicillin therapy is enough effective for pneumococcal infections except serious conditions such as meningitis and sepsis. Also we think it should be supported by multicenter studies.

  3. Distribution of quinolones, sulfonamides, tetracyclines in aquatic environment and antibiotic resistance in Indochina

    Directory of Open Access Journals (Sweden)

    Satoru eSuzuki

    2012-02-01

    Full Text Available Southeast Asia has become the center of rapid industrial development and economic growth. However, this growth has far outpaced investment in public infrastructure, leading to the unregulated release of many pollutants, including wastewater-related contaminants such as antibiotics. Antibiotics are of major concern because they can easily be released into the environment from numerous sources, and can subsequently induce development of antibiotic-resistant bacteria. Recent studies have shown that for some categories of drugs this source-to-environment antibiotic resistance relationship is more complex. This review summarizes current understanding regarding the presence of quinolones, sulfonamides, and tetracyclines in aquatic environments of Indochina and the prevalence of bacteria resistant to them. Several noteworthy findings are discussed: 1 quinolone contamination and the occurrence of quinolone resistance are not correlated; 2 occurrence of the sul sulfonamide resistance gene varies geographically; and 3 microbial diversity might be related to the rate of oxytetracycline resistance.

  4. Strategies to Combat Antibiotic Resistance in the Wastewater Treatment Plants

    Directory of Open Access Journals (Sweden)

    Fateme Barancheshme

    2018-01-01

    Full Text Available The main goal of this manuscript is to review different treatment strategies and mechanisms for combating the antibiotic resistant bacteria (ARB and antibiotic resistant genes (ARGs in the wastewater environment. The high amount of antibiotics is released into the wastewater that may promote selection of ARB and ARGs which find their way into natural environments. Emerging microbial pathogens and increasing antibiotic resistance among them is a global public health issue. The propagation and spread of ARB and ARGs in the environment may result in an increase of antibiotic resistant microbial pathogens which is a worldwide environmental and public health concern. A proper treatment of wastewater is essential before its discharge into rivers, lake, or sewage system to prevent the spread of ARB and ARGs into the environment. This review discusses various treatment options applied for combating the spread of ARB and ARGs in wastewater treatment plants (WWTPs. It was reported that low-energy anaerobic–aerobic treatment reactors, constructed wetlands, and disinfection processes have shown good removal efficiencies. Nanomaterials and biochar combined with other treatment methods and coagulation process are very recent strategies regarding ARB and ARGs removal and need more investigation and research. Based on current studies a wide-ranging removal efficiency of ARGs can be achieved depending on the type of genes present and treatment processes used, still, there are gaps that need to be further investigated. In order to find solutions to control dissemination of antibiotic resistance in the environment, it is important to (1 study innovative strategies in large scale and over a long time to reach an actual evaluation, (2 develop risk assessment studies to precisely understand occurrence and abundance of ARB/ARGs so that their potential risks to human health can be determined, and (3 consider operating and environmental factors that affect the

  5. Prevalence of the Antibiotic Resistance Genes in Coagulase-Positive-and Negative-Staphylococcus in Chicken Meat Retailed to Consumers

    OpenAIRE

    Osman, Kamelia; Badr, Jihan; Al-Maary, Khalid S.; Moussa, Ihab M. I.; Hessain, Ashgan M.; Girah, Zeinab M. S. Amin; Abo-shama, Usama H.; Orabi, Ahmed; Saad, Aalaa

    2016-01-01

    The use of antibiotics in farm management (growing crops and raising animals) has become a major area of concern. Its implications is the consequent emergence of antibiotic resistant bacteria (ARB) and accordingly their access into the human food chain with passage of antibiotic resistance genes (ARG) to the normal human intestinal microbiota and hence to other pathogenic bacteria causative human disease. Therefore, we pursued in this study to unravel the frequency and the quinolone resista...

  6. The role of midgut symbiotic bacteria in resistance of Anopheles stephensi (Diptera: Culicidae) to organophosphate insecticides.

    Science.gov (United States)

    Soltani, Aboozar; Vatandoost, Hassan; Oshaghi, Mohammad Ali; Enayati, Ahmad Ali; Chavshin, Ali Reza

    2017-09-01

    In the current study, the effects of the presence of symbiotic bacteria on the activity of the enzymes involved in An. stephensi resistance to temephos are evaluated for the first time. Four different strains (I. susceptible strain, II. resistant strain, III. resistant strain + antibiotic, and IV. resistant strain + bacteria) were considered in order to determine the possible effects of the symbiotic bacteria on their hosts' resistance to temephos. The median values of all enzymes of susceptible strain were compared with those of other resistant strains. The results of this study indicated a direct relationship between the presence of bacteria in the symbiotic organs of An. stephensi and resistance to temephos. The profile of enzymatic activities in the resistant strain changed to a susceptible status after adding antibiotic. The resistance of An. stephensi to temephos could be completely broken artificially by removing their bacterial symbionts in a resistant population.

  7. Antibiotic profiles of bacteria isolated on selective campylobacter media

    Science.gov (United States)

    The objective of this study was to determine antibiotic profiles of non-Campylobacter bacteria recovered on selective Campylobacter media. Broiler carcasses were obtained from a processing facility, and whole-carcass rinses were performed by shaking carcasses in plastic bags with 200 mL of distilled...

  8. Biofilm processes in treating mariculture wastewater may be a reservoir of antibiotic resistance genes

    International Nuclear Information System (INIS)

    Li, Shuai; Zhang, Shenghua; Ye, Chengsong; Lin, Wenfang; Zhang, Menglu; Chen, Lihua; Li, Jinmei; Yu, Xin

    2017-01-01

    Antibiotics are heavily used in Chinese mariculture, but only a small portion of the added antibiotics are absorbed by living creatures. Biofilm processes are universally used in mariculture wastewater treatment. In this study, removal of antibiotics (norfloxacin, rifampicin, and oxytetracycline) from wastewater by moving bed biofilm reactors (MBBRs) and the influence of antibiotics on reactor biofilm were investigated. The results demonstrated that there was no significant effect of sub-μg/L–sub-mg/L concentrations of antibiotics on TOC removal. Moreover, the relative abundance of antibiotic resistance genes (ARGs) and antibiotic resistance bacteria (ARB) in MBBR biofilm increased because of selective pressure of antibiotics. In addition, antibiotics decreased the diversity of the biofilm bacterial community and altered bacterial community structure. These findings provide an empirical basis for the development of appropriate practices for mariculture, and suggest that disinfection and advanced oxidation should be applied to eliminate antibiotics, ARGs, and ARB from mariculture wastewater. - Highlights: • The removal of antibiotics by Moving Bed Biofilm Reactors (MBBR) was investigated. • Biofilm process such as MBBR had little effect on the removal of the antibiotics. • The antibiotics decreased the diversity of biofilm bacterial community and altered bacterial community structure. • Biofilm processes in treating mariculture wastewater may be a reservoir of antibiotic resistance genes.

  9. Increasing transmission of antibiotic resistance from animals to humans

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Frimodt-Møller, Niels

    2011-01-01

    The importance of the animal reservoir for emergence of antimicrobial resistance in bacteria in humans is difficult to estimate. In this article we give our estimate of the importance and also highlight on which points we have become wiser during recent years. We conclude that it still is the human...... usage of antibiotics which contributes most to resistance observed in humans, but also that the contribution from animals is large and larger than estimated just a few years ago. This indicates the need to implement restriction on antimicrobial usage for both humans and animals....

  10. Increasing transmission of antibiotic resistance from animals to humans

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Frimodt-Møller, Niels

    2011-01-01

    usage of antibiotics which contributes most to resistance observed in humans, but also that the contribution from animals is large and larger than estimated just a few years ago. This indicates the need to implement restriction on antimicrobial usage for both humans and animals.......The importance of the animal reservoir for emergence of antimicrobial resistance in bacteria in humans is difficult to estimate. In this article we give our estimate of the importance and also highlight on which points we have become wiser during recent years. We conclude that it still is the human...

  11. 'Trade-off' in Antarctic bacteria: limnetic psychrotrophs concede multiple enzyme expressions for multiple metal resistance

    Digital Repository Service at National Institute of Oceanography (India)

    De; LokaBharathi, P.A.; Nair, S.; Chandramohan, D.

    The present study examines the metal and antibiotic resistant bacteria in ice and water from lakes east and west of the Indian base camp (Maitri) in Antarctica. The isolates from western and eastern lakes showed distinct geographical differences...

  12. Factors influencing the survival and leaching of tetracycline-resistant bacteria and Escherichia coli through structured agricultural fields

    DEFF Research Database (Denmark)

    Bech, Tina B.; Rosenbom, Annette E.; Kjaer, Jeanne

    2014-01-01

    Intense use of antibiotics in agricultural production may lead to the contamination of surface and groundwater by antibiotic-resistant bacteria. In the present study, the survival and leaching of E. coli and tetracycline-resistant bacteria were monitored at two well-structured agricultural fields...

  13. Antibiotic Susceptibility Pattern of Aerobic and Anaerobic Bacteria Isolated From Surgical Site Infection of Hospitalized Patients.

    Science.gov (United States)

    Akhi, Mohammad Taghi; Ghotaslou, Reza; Beheshtirouy, Samad; Asgharzadeh, Mohammad; Pirzadeh, Tahereh; Asghari, Babak; Alizadeh, Naser; Toloue Ostadgavahi, Ali; Sorayaei Somesaraei, Vida; Memar, Mohammad Yousef

    2015-07-01

    Surgical Site Infections (SSIs) are infections of incision or deep tissue at operation sites. These infections prolong hospitalization, delay wound healing, and increase the overall cost and morbidity. This study aimed to investigate anaerobic and aerobic bacteria prevalence in surgical site infections and determinate antibiotic susceptibility pattern in these isolates. One hundred SSIs specimens were obtained by needle aspiration from purulent material in depth of infected site. These specimens were cultured and incubated in both aerobic and anaerobic condition. For detection of antibiotic susceptibility pattern in aerobic and anaerobic bacteria, we used disk diffusion, agar dilution, and E-test methods. A total of 194 bacterial strains were isolated from 100 samples of surgical sites. Predominant aerobic and facultative anaerobic bacteria isolated from these specimens were the members of Enterobacteriaceae family (66, 34.03%) followed by Pseudomonas aeruginosa (26, 13.4%), Staphylococcus aureus (24, 12.37%), Acinetobacter spp. (18, 9.28%), Enterococcus spp. (16, 8.24%), coagulase negative Staphylococcus spp. (14, 7.22%) and nonhemolytic streptococci (2, 1.03%). Bacteroides fragilis (26, 13.4%), and Clostridium perfringens (2, 1.03%) were isolated as anaerobic bacteria. The most resistant bacteria among anaerobic isolates were B. fragilis. All Gram-positive isolates were susceptible to vancomycin and linezolid while most of Enterobacteriaceae showed sensitivity to imipenem. Most SSIs specimens were polymicrobial and predominant anaerobic isolate was B. fragilis. Isolated aerobic and anaerobic strains showed high level of resistance to antibiotics.

  14. Supplementary Material for: Detection of antibiotic resistance in probiotics of dietary supplements

    KAUST Repository

    Wong, Aloysius Tze

    2015-01-01

    Abstract Background Probiotics are live microorganisms that confer nutrition- and health-promoting benefits if consumed in adequate amounts. Concomitant with the demand for natural approaches to maintaining health is an increase in inclusion of probiotics in food and health products. Since probiotic bacteria act as reservoir for antibiotic resistant determinants, the transfer of these genes to pathogens sharing the same intestinal habitat is thus conceivable considering the fact that dietary supplements contain high amounts of often heterogeneous populations of probiotics. Such events can confer pathogens protection against commonly-used drugs. Despite numerous reports of antibiotic resistant probiotics in food and biological sources, the antibiogram of probiotics from dietary supplements remained elusive. Findings Here, we screened five commercially available dietary supplements for resistance towards antibiotics of different classes. Probiotics of all batches of products were resistant towards vancomycin while batch-dependent resistance towards streptomycin, aztreonam, gentamycin and/or ciprofloxacin antibiotics was detected for probiotics of brands Bi and Bn, Bg, and L. Isolates of brand Cn was also resistant towards gentamycin, streptomycin and ciprofloxacin antibiotics. Additionally, we also report a discrepancy between the enumerated viable bacteria amounts and the claims of the manufacturers. Conclusions This short report has highlighted the present of antibiotic resistance in probiotic bacteria from dietary supplements and therefore serves as a platform for further screenings and for in-depth characterization of the resistant determinants and the molecular machinery that confers the resistance.

  15. [Antibacterial activity of rare Streptomyces species against clinical resistant bacteria].

    Science.gov (United States)

    Boughachiche, Faiza; Reghioua, Sihem; Zerizer, Habiba; Boulahrouf, Abderrahmane

    2012-01-01

    In the search for new antibiotics from Steptomyces, investigating extremes habitats enhances the probability of isolating novel producers. In this context, the antibacterial activity of four Streptomyces strains isolated from Ezzmoul saltpans was studied. Two of them showed antibacterial activity against antibiotic's resistant bacteria (Bacillus cereus: β-lactamines and sulfamides resistant, Streptococcus faecalis: penicillin, tetracycline and cotrimoxazole resistant, and Staphylococcus aureus Mu 50: vancomycine resistant). The most active Streptomyces strain produces one type of polar bioactive molecules that resists to temperature variation and light exposition. Its activity appears in the first culture day and reaches its maximal value in the fourth day. The second strain presents themoresistant activity that reaches its maximal value in the first culture day. It produces two types of bioactive molecules, one is polar and the second is non polar (according to thin layer chromatography technique results).

  16. Graphene oxide in the water environment could affect tetracycline-antibiotic resistance.

    Science.gov (United States)

    Guo, Mei-Ting; Zhang, Guo-Sheng

    2017-09-01

    In recent years, the influence of new materials like nanoparticles in the water environment on biological substances has been widely studied. Antibiotic resistance genes (ARGs) represent a new type of pollutant in the environment. Graphene oxide (GO), as a nano material, because of its unique structure, may have an impact on antibiotic resistance bacteria (ARB) and ARGs; however the research in this area is rarely reported. Therefore, this study mainly investigated the effects of GO on bacterial antibiotic resistance. The results showed that GO had a limited effect on ARB inactivation. A high concentration of GO (>10 mg/L) can damage resistant plasmids to reduce bacterial resistance to antibiotics, but low concentrations of GO (antibiotic resistance needs further investigation. Copyright © 2017. Published by Elsevier Ltd.

  17. Distribution of antibiotic resistance in urban watershed in Japan

    International Nuclear Information System (INIS)

    Ham, Young-Sik; Kobori, Hiromi; Kang, Joo-Hyon; Matsuzaki, Takayuki; Iino, Michiyo; Nomura, Hayashi

    2012-01-01

    Antibiotic-resistant E. coli concentrations showed large spatial and temporal variations, with greater concentrations observed in tributaries and downstream than in the upstream and midstream. Twenty percent of the geometric mean concentrations of antibiotic-resistant E. coli in the Tama River basin (Japan) exceeded the maximum acceptable concentration of indicator E. coli established by the USEPA. The indicator E. coli concentrations were positively correlated with those of antibiotic-resistant E. coli and multiple-antibiotic-resistant E. coli (resistance to more than two kinds of antibiotics), respectively, but not the detection rate of antibiotic-resistant E. coli, implying that use of antibiotic-resistant E. coli concentration rather than the detection rate can be a better approach for water quality assessment. Multiple-antibiotic-resistant E. coli is a useful indicator for estimating the resistance diffusion, water quality degradation and public health risk potential. This assessment provides beneficial information for setting national regulatory or environmental standards and managing integrated watershed areas. - Highlights: ► We extensively observed antibiotic-resistant E. coli (AREc) in Tama River (Japan). ► AREc count rather than the detection rate is better approach for water quality test. ► Multiple-AREc is resistant to the antibiotic to which single-AREc has no resistance. ► Multiple-AREc increase will accelerate the diffusion of antibiotic resistance. - Multiple-antibiotic-resistant E. coli in the watershed can cause the diffusion of conventionally rare antibiotic resistance.

  18. Sampling and Pooling Methods for Capturing Herd Level Antibiotic Resistance in Swine Feces using qPCR and CFU Approaches

    DEFF Research Database (Denmark)

    Schmidt, Gunilla Veslemøy; Mellerup, Anders; Christiansen, Lasse Engbo

    2015-01-01

    The aim of this article was to define the sampling level and method combination that captures antibiotic resistance at pig herd level utilizing qPCR antibiotic resistance gene quantification and culture-based quantification of antibiotic resistant coliform indicator bacteria. Fourteen qPCR assays...... for commonly detected antibiotic resistance genes were developed, and used to quantify antibiotic resistance genes in total DNA from swine fecal samples that were obtained using different sampling and pooling methods. In parallel, the number of antibiotic resistant coliform indicator bacteria was determined...... when comparing individual sampling and pooling methods. qPCR on pooled samples was found to be a good representative for the general resistance level in a pig herd compared to the coliform CFU counts. It had significantly reduced relative standard deviations compared to coliform CFU counts in the same...

  19. High Levels of Antibiotic Resistance but No Antibiotic Production Detected Along a Gypsum Gradient in Great Onyx Cave, KY, USA

    Directory of Open Access Journals (Sweden)

    Kathleen Lavoie

    2017-09-01

    Full Text Available A preliminary study of antibiotic production and antibiotic resistance was conducted in Great Onyx Cave in Mammoth Cave National Park, KY, to determine if gypsum (CaSO4∙2H2O affects these bacterial activities. The cave crosses through the width of Flint Ridge, and passages under the sandstone caprock are dry with different amounts of gypsum. The Great Kentucky Desert hypothesis posits that gypsum limits the distribution of invertebrates in the central areas of Great Onyx Cave. Twenty-four bacterial isolates were cultivated from swabs and soils. Using three methods (soil crumb, soil crumb with indicator bacteria, and the cross-streak method using isolated bacteria we did not detect any production of antibiotics. Antibiotic resistance was widespread, with all 24 isolates resistant to a minimum of two antibiotics of seven tested, with three isolates resistant to all. Antibiotic resistance was high and not correlated with depth into the cave or the amount of gypsum. The Great Kentucky Desert hypothesis of the negative effects of gypsum seems to have no impact on bacterial activity.

  20. Current scenario of antibiotic resistance and latest strategies to overcome it

    Directory of Open Access Journals (Sweden)

    Mohankumar J Megha

    2014-09-01

    Full Text Available Antibiotic resistance in microorganisms has become a critical health issue these days and has evolved to become a worldwide health threat. Over a decade, the resistance level of bacteria has increased many folds due to various factors, accounting to the added pressure on the environmental resistome. Infections that are resistant to these antibiotics show potentially devastating effects on public health, often affecting developing countries. This review focuses on the present scenario of antibiotic resistance and enlists some of the strategies to combat this global community threat.

  1. Study of antibiotic resistance of staph aureus and coagulase negative staphylococci isolated from patient samples

    Directory of Open Access Journals (Sweden)

    M Anvary

    2006-04-01

    Full Text Available Introduction: Drug resistant Staphylococci are the most important agents of nosocomial infections. In this survey, effect of different antibiotics on these bacteria and their drug resistance was investigated. Methods: The study included 500 strains of Staphylococci. Minimum Inhibitory Concentrations of all antibiotics was determined by the broth macro dilution technique and standard methods from the National Committee for Clinical Laboratory Standards. Result : Oxacillin resistance of S. aureus was 14.2% and that of coagulase-negative staphylococci was 53.4%. The activity of different antibiotics is presented in detail. Conclusion: Surveillance of strains resistant to methicillin is necessary.

  2. Occurrence of antibiotic resistance and characterization of resistant genes and integrons in Enterobacteriaceae isolated from integrated fish farms south China

    Science.gov (United States)

    Su, Hao-Chang; Ying, Guang-Guo; Tao, Ran; Zhang, Rui-Quan; Fogarty, Lisa R.; Kolpin, Dana W.

    2011-01-01

    Antibiotics are still widely applied in animal husbandry to prevent diseases and used as feed additives to promote animal growth. This could result in antibiotic resistance to bacteria and antibiotic residues in animals. In this paper, Enterobacteriaceae isolated from four integrated fish farms in Zhongshan, South China were tested for antibiotic resistance, tetracycline resistance genes, sulfonamide resistance genes, and class 1 integrons. The Kirby-Bauer disk diffusion method and polymerase chain reaction (PCR) assays were carried out to test antibiotic susceptibility and resistance genes, respectively. Relatively high antibiotic resistance frequencies were found, especially for ampicillin (80%), tetracycline (52%), and trimethoprim (50%). Out of 203 Enterobacteriaceae isolates, 98.5% were resistant to one or more antibiotics tested. Multiple antibiotic resistance (MAR) was found highest in animal manures with a MAR index of 0.56. Tetracycline resistance genes (tet(A), tet(C)) and sulfonamide resistance genes (sul2) were detected in more than 50% of the isolates. The intI1 gene was found in 170 isolates (83.7%). Both classic and non-classic class 1 integrons were found. Four genes, aadA5, aadA22, dfr2, and dfrA17, were detected. To our knowledge, this is the first report for molecular characterization of antibiotic resistance genes in Enterobacteriaceae isolated from integrated fish farms in China and the first time that gene cassette array dfrA17-aadA5 has been detected in such fish farms. Results of this study indicated that fish farms may be a reservoir of highly diverse and abundant antibiotic resistant genes and gene cassettes. Integrons may play a key role in multiple antibiotic resistances posing potential health risks to the general public and aquaculture.

  3. Quantifying Attachment and Antibiotic Resistance of from Conventional and Organic Swine Manure.

    Science.gov (United States)

    Zwonitzer, Martha R; Soupir, Michelle L; Jarboe, Laura R; Smith, Douglas R

    2016-03-01

    Broad-spectrum antibiotics are often administered to swine, contributing to the occurrence of antibiotic-resistant bacteria in their manure. During land application, the bacteria in swine manure preferentially attach to particles in the soil, affecting their transport in overland flow. However, a quantitative understanding of these attachment mechanisms is lacking, and their relationship to antibiotic resistance is unknown. The objective of this study is to examine the relationships between antibiotic resistance and attachment to very fine silica sand in collected from swine manure. A total of 556 isolates were collected from six farms, two organic and four conventional (antibiotics fed prophylactically). Antibiotic resistance was quantified using 13 antibiotics at three minimum inhibitory concentrations: resistant, intermediate, and susceptible. Of the 556 isolates used in the antibiotic resistance assays, 491 were subjected to an attachment assay. Results show that isolates from conventional systems were significantly more resistant to amoxicillin, ampicillin, chlortetracycline, erythromycin, kanamycin, neomycin, streptomycin, tetracycline, and tylosin ( < 0.001). Results also indicate that isolated from conventional systems attached to very fine silica sand at significantly higher levels than those from organic systems ( < 0.001). Statistical analysis showed that a significant relationship did not exist between antibiotic resistance levels and attachment in from conventional systems but did for organic systems ( < 0.001). Better quantification of these relationships is critical to understanding the behavior of in the environment and preventing exposure of human populations to antibiotic-resistant bacteria. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  4. Antibiotic resistance patterns and beta-lactamase identification in ...

    African Journals Online (AJOL)

    Background. Antibiotic resistance is a growing problem worldwide. Mechanisms of resistance vary, and some can confer resistance to multiple classes of antibiotics. Objective. To characterise the antibiotic resistance profiles of Escherichia coli isolates obtained from stool samples of young rural children exposed or ...

  5. Antibiotic Resistance Factors and Alternatives to Antimicrobial Growth Factors within Animal Husbandry

    OpenAIRE

    Reyes, Emory

    2014-01-01

    The repercussions of antibiotic resistance in humans give scientists a vivid picture of the effectsof microbial evolution. These repercussions can be felt economically and scientifically as thedemand for stronger antibiotics grows stronger, yet the availability for such an effect remainslow. Citizens must pay more money in order to access antibiotics from their healthcareproviders; however, if treatment is not completed, bacteria become increasingly immune toantibiotics, closing off pathways ...

  6. Effect of Prophylactic Antibiotic Use in the Development of Antibiotic Resistance in Children with Recurrent Urinary Tract Infections

    Directory of Open Access Journals (Sweden)

    Mehmet Karacı

    2017-09-01

    Full Text Available Aim: Although prophylactic antibiotic treatment is still debatable, it is currently in use in recurrent urinary tract infections (UTIs. In the present study, we aimed to observe if prophylactic antibiotic use had any effect on the development of antibiotic resistance in patients with recurrent UTIs who we followed up in our clinic. Methods: The present study was performed on patients aged between one month and 16 years, who had recurrent UTIs, and were followed up by the Department of Pediatrics at Bülent Ecevit University Medical School. Patient files were retrospectively reviewed, and 50 patients who received antibiotic prophylaxis and 100 patients without prophylaxis were enrolled in the study. Urinary tests, subsequent urinary culture results, and antibiotic resistances were compared between the groups. Results: The mean age was 42.7±44.2 months. The most frequently cultured isolated bacterium was Escherichia coli (E. coli (58.4%. No difference was determined in bacteria in cultures between prophylaxis receivers and non-receivers. Isolation rate of E. coli was higher in urinary cultures in females than in males (p<0.001. When antibiotic resistance of all urinary culture-isolated bacteria was compared between the two groups, there was no statistically significant difference. However, an increased resistance against amoxicillin/clavulanic acid, ceftriaxone, and piperacillin was determined in prophylaxis group in whom E. coli was grown. In this study, general antibiotic resistance was most frequently observed against ampicillin (71.9%. Conclusion: In the present study, we observed that prophylaxis did not contribute so much to resistance other than E. coli. We recommend not preferring antibiotics which have increased resistance in our institution especially in children receiving prophylaxis for empirical treatment.

  7. The antibiotic resistome of free-living and particle-attached bacteria under a reservoir cyanobacterial bloom.

    Science.gov (United States)

    Guo, Yunyan; Liu, Min; Liu, Lemian; Liu, Xuan; Chen, Huihuang; Yang, Jun

    2018-05-04

    In freshwater systems, both antibiotic resistance genes (ARGs) and cyanobacterial blooms attract global public health concern. Cyanobacterial blooms can greatly impact bacterial taxonomic communities, but very little is known about the influence of the blooms on antibiotic resistance functional community. In this study, the ARGs in both free-living (FL) and particle-attached (PA) bacteria under bloom and non-bloom conditions were simultaneously investigated in a subtropical reservoir using high-throughput approaches. In total, 145 ARGs and 9 mobile genetic elements (MGEs) were detected. The most diverse and dominant of which (68.93%) were multidrug resistance genes and efflux pump mechanism. The richness of ARGs in both FL and PA bacteria was significantly lower during the bloom period compared with non-bloom period. The abundance of ARGs in FL bacteria was significantly lower under bloom condition than in the non-bloom period, but the abundance of ARGs in PA bacteria stayed constant. More importantly, the resistant functional community in PA bacteria was more strongly influenced by the cyanobacterial bloom than in the FL bacteria, although >96% ARGs were shared in both FL and PA bacteria or both bloom and non-bloom periods. We also compared the community compositions between taxonomy and function, and found antibiotic resistant communities were highly variable and exhibited lower similarity between bloom and non-bloom periods than seen in the taxonomic composition, with an exception of FL bacteria. Altogether, cyanobacterial blooms appear to have stronger inhibitory effect on ARG abundance in FL bacteria, and stronger influence on antibiotic resistant community composition in PA bacteria. Our results further suggested that both neutral and selective processes interactively affected the ARG composition dynamics of the FL and PA bacteria. However, the antibiotic resistant community of FL bacteria exhibited a higher level of temporal stochasticity following the bloom

  8. Anti-virulence approaches and novel peptidomimetics for combating resistant and biofilm associated bacteria

    DEFF Research Database (Denmark)

    Liu, Yang

    Anti-virulence approaches and novel peptidomimetics for combating resistant and biofilm associated bacteria The misuse and overuse of antibiotics has a broad impact on the environment. Antibiotic resistance has become a major threat for modern medical treatment of infectious diseases. There are m......Anti-virulence approaches and novel peptidomimetics for combating resistant and biofilm associated bacteria The misuse and overuse of antibiotics has a broad impact on the environment. Antibiotic resistance has become a major threat for modern medical treatment of infectious diseases...... consisting of microcolonies embedded in self-produced extracellular polymer substances (EPS). EPS can contribute to cell-cell adhesion and restrict antibiotic penetration. Biofilm cells show much greater resistance to stressful conditions than their free-living counterparts. Conventional treatment strategies...

  9. An Antibiotic Selection System For Protein Overproducing Bacteria

    DEFF Research Database (Denmark)

    Rennig, Maja; Nørholm, Morten

    2015-01-01

    Introduction: Protein overproduction is a major bottleneck for analyses of membrane proteins and for the construction of cell factories. Screening for optimized protein production can be very time consuming. In this study we show that the coupling of antibiotic resistance to poorly produced...... membrane proteins of Escherichia coli can be used as a fast and simple selection system for protein overproduction.Methods: We designed an expression plasmid encoding the gene of interest and an additional, inducible antibiotic resistance marker. Both genes were linked by a hairpin structure...... that translationally couples the genes. Consequently, high expressing gene variants also allow for higher production of the coupled antibiotic resistance marker. Therefore, high expressing gene variants in a library can be determined either by plating the expression library on selection plates or by growing...

  10. Antibiotic resistance--consequences for animal health, welfare, and food production.

    Science.gov (United States)

    Bengtsson, Björn; Greko, Christina

    2014-05-01

    Most of the literature on the consequences of emergence and spread of bacteria resistant to antibiotics among animals relate to the potential impact on public health. But antibiotics are used to treat sick animals, and resistance in animal pathogens may lead to therapy failure. This has received little scientific attention, and therefore, in this article, we discuss examples that illustrate the possible impact of resistance on animal health and consequences thereof. For all animals, there may be a negative effect on health and welfare when diseases cannot be treated. Other consequences will vary depending on why and how different animal species are kept. Animals kept as companions or for sports often receive advanced care, and antibiotic resistance can lead to negative social and economic consequences for the owners. Further, spread of hospital-acquired infections can have an economic impact on the affected premises. As to animals kept for food production, antibiotics are not needed to promote growth, but, if infectious diseases cannot be treated when they occur, this can have a negative effect on the productivity and economy of affected businesses. Antibiotic resistance in animal bacteria can also have positive consequences by creating incentives for adoption of alternative regimes for treatment and prevention. It is probable that new antibiotic classes placed on the market in the future will not reach veterinary medicine, which further emphasizes the need to preserve the efficacy of currently available antibiotics through antibiotic stewardship. A cornerstone in this work is prevention, as healthy animals do not need antibiotics.

  11. Antibiotics resistance of Stenotrophomonas maltophilia strains ...

    African Journals Online (AJOL)

    Introduction. Stenotrophomonas maltophilia is a resistant pathogen that can cause bacteremia, endocarditis, respiratory system, central nervous system and urinary tract infections in patients with risk factors like malignancy or neutrope- nia, use of broad-spectrum antibiotics like carbapenem or long-term hospitalization1,2.

  12. Antibiotic resistance properties of uropathogenic Escherichia coli ...

    African Journals Online (AJOL)

    Purpose: To investigate the antibiotic resistance pattern of uropathogenic Escherichia coli (UPEC) strains isolated from pregnant women with history of recurrent urinary tract infections (RUTIs) and healthy pregnant women. Methods: A total of 485 high vaginal swab specimens were collected from pregnant women with ...

  13. Bacterial antibiotic resistance levels in Danish farmland as a result of treatment with pig manure slurry

    DEFF Research Database (Denmark)

    Sengeløv, Gitte; Agersø, Yvonne; Halling-Sørensen, B.

    2003-01-01

    Resistance to tetracycline, macrolides and streptomycin was measured for a period of 8 months in soil bacteria obtained from farmland treated with pig manure slurry. This was done by spread plating bacteria on selective media (Luria Bertani (LB) medium supplemented with antibiotics). To account...

  14. Antibiotic-producing bacteria from stag beetle mycangia.

    Science.gov (United States)

    Miyashita, Atsushi; Hirai, Yuuki; Sekimizu, Kazuhisa; Kaito, Chikara

    2015-02-01

    The search for new antibiotics or antifungal agents is crucial for the chemotherapies of infectious diseases. The limited resource of soil bacteria makes it difficult to discover such new drug candidate. We, therefore, focused on another bacterial resource than soil bacteria, the microbial flora of insect species. In the present study, we isolated 40 strains of bacteria and fungi from the mycangia of three species of stag beetle, Dorcus hopei binodulosus, Dorcus rectus, and Dorcus titanus pilifer. We identified those species with their ribosomal DNA sequences, and revealed that Klebsiella spp. are the most frequent symbiont in the stag beetle mycangia. We examined whether these microorganisms produce antibiotics against a Gram-negative bacterium, Escherichia coli, a Gram-positive bacterium, Staphylococcus aureus, or a fungus, Cryptococcus neoformans. Culture supernatants from 33, 29, or 18 strains showed antimicrobial activity against E. coli, S. aureus, or C. neoformans, respectively. These findings suggest that bacteria present in the mycangia of stag beetles are useful resources for screening novel antibiotics.

  15. THE STUDY OF ANTIBIOTIC- AND FAGOSENSITIVITY OF NOSOCOMIAL STRAINS BACTERIA ISOLATED FROM TRANSPLANTED PATIENTS

    Directory of Open Access Journals (Sweden)

    N. I. Gabrielan

    2011-01-01

    Full Text Available Antibiotic and fagosensitivity most etiologically important nosocomial strains of bacteria – Pseudomonas aeru- ginosa, Klebsiella pneumoniae, E. coli, Proteus spp., Staphylococcus spp. were studied. Multiple drug-resistant bacteria as gram-positive and gram-negative, isolated from 8 substrates, had been demonstrated. With regard to the sensitivity of Pseudomonas aeruginosa >40% was observed in 40–50% of the strains to aminoglycosides – aztreonam, amikacin, netilmicin, and only 23–25% of the strains – to gentamicin and levofloxacin (an average of antibiotic susceptibility was 27%. All strains of ESBL Klebsiella drew up and were sensitive only to imipenem, meropenem and aminoglycosides. Specific phages lysed 43–48% of the strains Pseudomonas aeruginosa and Klebsiella pneumoniae, E. coli, Pro- teus spp., multidrug resistant strains of Staphylococcus spp. It is proposed to introduce the use of phages in clinical practice. 

  16. Antibiotic resistance and plasmid carriage among Escherichia coli isolates from chicken meat in Malaysia

    International Nuclear Information System (INIS)

    Tin Tin Myaing; Saleha, A.A.; Arifah, A.K.; Raha, A.R.

    2005-01-01

    Escherichia coli isolates from 131 raw chicken meat samples were tested for susceptibility to 12 antibiotics. Plasmids were isolated from many samples and their DNA molecular weight calculated. An 81.7% plasmid occurrence rate was observed among the isolates, ranging from 0 to 8 in number and with sizes from 1.2 to 118.6 MDa. Plasmids were detected in 93.8% of E. coIi isolates resistant to all 12 antibiotics, and in 90.5% of E. coli isolates resistant to 11. Three (2.8%) isolates harboured 8 plasmids and were resistant to all 12 antibiotics. Antibiotic resistant genes in bacteria are usually carried in extrachromosomal DNA and it is postulated that E. coli with a high number of plasmids possesses wider resistance to antibiotics. (author)

  17. Increasing awareness about antibiotic use and resistance: a hands-on project for high school students.

    Science.gov (United States)

    Fonseca, Maria João; Santos, Catarina L; Costa, Patrício; Lencastre, Leonor; Tavares, Fernando

    2012-01-01

    Health-promoting education is essential to foster an informed society able to make decisions about socio-scientific issues based on scientifically sustained criteria. Antibiotic resistance is currently a major public health issue. Considering that irrational antibiotic use has been associated with the development and widespread of antibiotic resistant bacteria, educational interventions to promote prudent antibiotic consumption are required. This study focuses on the outcomes of an interventional program implemented at the University of Porto, Portugal, to promote awareness about antibiotic resistance at high school levels (15-17 year old). The project Microbiology recipes: antibiotics à la carte articulates a set of wet and dry lab activities designed to promote the participants' understanding of concepts and processes underlying antibiotics' production and activity, such as the notion of mechanisms of action of antibiotics. Following a mix-method approach based on a pre-/post design, the effectiveness of this project was assessed by gathering data from surveys, direct observation and analysis of artifacts of 42 high school students (aged 15 and 16 years). The results indicate that the participants developed a more comprehensive picture of antibiotic resistance. The project was shown to promote more sophisticated conceptualizations of bacteria and antibiotics, increased awareness about the perils of antibiotic resistance, and enhanced consciousness towards measures that can be undertaken to mitigate the problem. The participants regarded their experiences as enjoyable and useful, and believed that the project contributed to improve their understanding and raise their interest about the issues discussed. Furthermore, there were also improvements in their procedural skills concerning the laboratory techniques performed. This study evidences the possibility of increasing high school students' awareness about the consequences of antibiotic resistance and the

  18. Multi-bacteria multi-antibiotic testing using surface enhanced Raman spectroscopy (SERS) for urinary tract infection (UTI) diagnosis

    Science.gov (United States)

    Hadjigeorgiou, Katerina; Kastanos, Evdokia; Pitris, Costas

    2013-06-01

    The inappropriate use of antibiotics leads to antibiotic resistance, which is a major health care problem. The current method for determination of bacterial susceptibility to antibiotics requires overnight cultures. However most of the infections cannot wait for the results to receive treatment, so physicians administer general spectrum antibiotics. This results in ineffective treatments and aggravates the rising problem of antibiotic resistance. In this work, a rapid method for diagnosis and antibiogram for a bacterial infection was developed using Surface Enhanced Raman Spectroscopy (SERS) with silver nanoparticles. The advantages of this novel method include its rapidness and efficiency which will potentially allow doctors to prescribe the most appropriate antibiotic for an infection. SERS spectra of three species of gram negative bacteria, Escherichia coli, Proteus spp., and Klebsiella spp. were obtained after 0 and 4 hour exposure to the seven different antibiotics. Bacterial strains were diluted in order to reach the concentration of (2x105 cfu/ml), cells/ml which is equivalent to the minimum concentration found in urine samples from UTIs. Even though the concentration of bacteria was low, species classification was achieved with 94% accuracy using spectra obtained at 0 hours. Sensitivity or resistance to antibiotics was predicted with 81%-100% accuracy from spectra obtained after 4 hours of exposure to the different antibiotics. This technique can be applied directly to urine samples, and with the enhancement provided by SERS, this method has the potential to be developed into a rapid method for same day UTI diagnosis and antibiogram.

  19. [Antibiotic resistance: measures urgently needed].

    NARCIS (Netherlands)

    Kluytmans, J.; Vandenbroucke-Grauls, C.M.; Meer, J.W.M. van der

    2010-01-01

    Antimicrobial resistance is increasing rapidly and there are hardly any new antimicrobial agents to be expected in the coming years. The number of patients affected by extended spectrum beta-lactamase producing organisms (ESBLs) is rising and there are strong indications that this is caused in part

  20. Distribution of multiple antibiotic resistant Vibrio spp across Palk Bay

    Digital Repository Service at National Institute of Oceanography (India)

    Sneha, K.G.; Anas, A.; Jayalakshmy, K.V.; Jasmin, C.; VipinDas, P.V.; Pai, S.S.; Pappu, S.; Nair, M.; Muraleedharan, K.R.; Sudheesh, K.; Nair, S.

    Presence of multiple antibiotic resistant microorganisms in marine systems is increasingly a focus of concern as they pose potential health risk to humans and animals. The present study reports the distribution, diversity, antibiotic resistance...

  1. Emerging antibiotic resistant enteric bacterial flora among food ...

    African Journals Online (AJOL)

    Emerging antibiotic resistant enteric bacterial flora among food animals in Abeokuta, Nigeria. ... Nigerian Journal of Animal Production ... Bacterial resistance to antibiotic in food animals is an emerging public health concern as a result of ...

  2. Changes in Bacterial Resistance Patterns of Pediatric Urinary Tract Infections and Rationale for Empirical Antibiotic Therapy

    Directory of Open Access Journals (Sweden)

    İbrahim Gökçe

    2017-10-01

    Full Text Available Background: The causative agent spectrum and resistance patterns of urinary tract infections in children are affected by many factors. Aims: To demonstrate antibiotic resistance in urinary tract infections and changing ratio in antibiotic resistance by years. Study Design: Retrospective cross-sectional study. Methods: We analysed antibiotic resistance patterns of isolated Gram (- bacteria during the years 2011-2014 (study period 2 in children with urinary tract infections. We compared these findings with data collected in the same centre in 2001-2003 (study period 1. Results: Four hundred and sixty-five uncomplicated community-acquired Gram (- urinary tract infections were analysed from 2001-2003 and 400 from 2011-2014. Sixty-one percent of patients were female (1.5 girls : 1 boy. The mean age of children included in the study was 3 years and 9 months. Escherichia coli was the predominant bacteria isolated during both periods of the study (60% in study period 1 and 73% in study period 2. Bacteria other than E. coli demonstrated a higher level of resistance to all of the antimicrobials except trimethoprim-sulfamethoxazole than E. coli bacteria during the years 2011-2014. In our study, we found increasing resistance trends of urinary pathogens for cefixime (from 1% to 15%, p0.05. Conclusion: In childhood urinary tract infections, antibiotic resistance should be evaluated periodically and empiric antimicrobial therapy should be decided according to antibiotic sensitivity results

  3. Clusters of Antibiotic Resistance Genes Enriched Together Stay Together in Swine Agriculture.

    Science.gov (United States)

    Johnson, Timothy A; Stedtfeld, Robert D; Wang, Qiong; Cole, James R; Hashsham, Syed A; Looft, Torey; Zhu, Yong-Guan; Tiedje, James M

    2016-04-12

    Antibiotic resistance is a worldwide health risk, but the influence of animal agriculture on the genetic context and enrichment of individual antibiotic resistance alleles remains unclear. Using quantitative PCR followed by amplicon sequencing, we quantified and sequenced 44 genes related to antibiotic resistance, mobile genetic elements, and bacterial phylogeny in microbiomes from U.S. laboratory swine and from swine farms from three Chinese regions. We identified highly abundant resistance clusters: groups of resistance and mobile genetic element alleles that cooccur. For example, the abundance of genes conferring resistance to six classes of antibiotics together with class 1 integrase and the abundance of IS6100-type transposons in three Chinese regions are directly correlated. These resistance cluster genes likely colocalize in microbial genomes in the farms. Resistance cluster alleles were dramatically enriched (up to 1 to 10% as abundant as 16S rRNA) and indicate that multidrug-resistant bacteria are likely the norm rather than an exception in these communities. This enrichment largely occurred independently of phylogenetic composition; thus, resistance clusters are likely present in many bacterial taxa. Furthermore, resistance clusters contain resistance genes that confer resistance to antibiotics independently of their particular use on the farms. Selection for these clusters is likely due to the use of only a subset of the broad range of chemicals to which the clusters confer resistance. The scale of animal agriculture and its wastes, the enrichment and horizontal gene transfer potential of the clusters, and the vicinity of large human populations suggest that managing this resistance reservoir is important for minimizing human risk. Agricultural antibiotic use results in clusters of cooccurring resistance genes that together confer resistance to multiple antibiotics. The use of a single antibiotic could select for an entire suite of resistance genes if

  4. Where antibiotic resistance mutations meet quorum-sensing

    Directory of Open Access Journals (Sweden)

    Rok Krašovec

    2014-06-01

    Full Text Available We do not need to rehearse the grim story of the global rise of antibiotic resistant microbes. But what if it were possible to control the rate with which antibiotic resistance evolves by de novo mutation? It seems that some bacteria may already do exactly that: they modify the rate at which they mutate to antibiotic resistance dependent on their biological environment. In our recent study [Krašovec, et al. Nat. Commun. (2014, 5, 3742] we find that this modification depends on the density of the bacterial population and cell-cell interactions (rather than, for instance, the level of stress. Specifically, the wild-type strains of Escherichia coli we used will, in minimal glucose media, modify their rate of mutation to rifampicin resistance according to the density of wild-type cells. Intriguingly, the higher the density, the lower the mutation rate (Figure 1. Why this novel density-dependent ‘mutation rate plasticity’ (DD-MRP occurs is a question at several levels. Answers are currently fragmentary, but involve the quorum-sensing gene luxS and its role in the activated methyl cycle.

  5. Agriculture and food animals as a source of antimicrobial-resistant bacteria

    Directory of Open Access Journals (Sweden)

    Economou V

    2015-04-01

    Full Text Available Vangelis Economou,1 Panagiota Gousia2 1Department of Hygiene and Technology of Food of Animal Origin, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece; 2Food-Water Microbiology Unit, Department of Microbiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, Ioannina, Greece Abstract: One of the major breakthroughs in the history of medicine is undoubtedly the discovery of antibiotics. Their use in animal husbandry and veterinary medicine has resulted in healthier and more productive farm animals, ensuring the welfare and health of both animals and humans. Unfortunately, from the first use of penicillin, the resistance countdown started to tick. Nowadays, the infections caused by antibiotic-resistant bacteria are increasing, and resistance to antibiotics is probably the major public health problem. Antibiotic use in farm animals has been criticized for contributing to the emergence of resistance. The use and misuse of antibiotics in farm animal settings as growth promoters or as nonspecific means of infection prevention and treatment has boosted antibiotic consumption and resistance among bacteria in the animal habitat. This reservoir of resistance can be transmitted directly or indirectly to humans through food consumption and direct or indirect contact. Resistant bacteria can cause serious health effects directly or via the transmission of the antibiotic resistance traits to pathogens, causing illnesses that are difficult to treat and that therefore have higher morbidity and mortality rates. In addition, the selection and proliferation of antibiotic-resistant strains can be disseminated to the environment via animal waste, enhancing the resistance reservoir that exists in the environmental microbiome. In this review, an effort is made to highlight the various factors that contribute to the emergence of antibiotic resistance in farm animals and to

  6. Antibiotic Resistant Bacterial Isolates from Captive Green Turtles and In Vitro Sensitivity to Bacteriophages

    Directory of Open Access Journals (Sweden)

    Alessandro Delli Paoli Carini

    2017-01-01

    Full Text Available This study aimed to test multidrug resistant isolates from hospitalised green turtles (Chelonia mydas and their environment in North Queensland, Australia, for in vitro susceptibility to bacteriophages. Seventy-one Gram-negative bacteria were isolated from green turtle eye swabs and water samples. Broth microdilution tests were used to determine antibiotic susceptibility. All isolates were resistant to at least two antibiotics, with 24% being resistant to seven of the eight antibiotics. Highest resistance rates were detected to enrofloxacin (77% and ampicillin (69.2%. More than 50% resistance was also found to amoxicillin/clavulanic acid (62.5%, ceftiofur (53.8%, and erythromycin (53.3%. All the enriched phage filtrate mixtures resulted in the lysis of one or more of the multidrug resistant bacteria, including Vibrio harveyi and V. parahaemolyticus. These results indicate that antibiotic resistance is common in Gram-negative bacteria isolated from hospitalised sea turtles and their marine environment in North Queensland, supporting global concern over the rapid evolution of multidrug resistant genes in the environment. Using virulent bacteriophages as antibiotic alternatives would not only be beneficial to turtle health but also prevent further addition of multidrug resistant genes to coastal waters.

  7. Old and New Glycopeptide Antibiotics: Action and Resistance

    Directory of Open Access Journals (Sweden)

    Elisa Binda

    2014-11-01

    Full Text Available Glycopeptides are considered antibiotics of last resort for the treatment of life-threatening infections caused by relevant Gram-positive human pathogens, such as Staphylococcus aureus, Enterococcus spp. and Clostridium difficile. The emergence of glycopeptide-resistant clinical isolates, first among enterococci and then in staphylococci, has prompted research for second generation glycopeptides and a flurry of activity aimed at understanding resistance mechanisms and their evolution. Glycopeptides are glycosylated non-ribosomal peptides produced by a diverse group of soil actinomycetes. They target Gram-positive bacteria by binding to the acyl-D-alanyl-D-alanine (D-Ala-D-Ala terminus of the growing peptidoglycan on the outer surface of the cytoplasmatic membrane. Glycopeptide-resistant organisms avoid such a fate by replacing the D-Ala-D-Ala terminus with D-alanyl-D-lactate (D-Ala-D-Lac or D-alanyl-D-serine (D-Ala-D-Ser, thus markedly reducing antibiotic affinity for the cellular target. Resistance has manifested itself in enterococci and staphylococci largely through the expression of genes (named van encoding proteins that reprogram cell wall biosynthesis and, thus, evade the action of the antibiotic. These resistance mechanisms were most likely co-opted from the glycopeptide producing actinomycetes, which use them to avoid suicide during antibiotic production, rather than being orchestrated by pathogen bacteria upon continued treatment. van-like gene clusters, similar to those described in enterococci, were in fact identified in many glycopeptide-producing actinomycetes, such as Actinoplanes teichomyceticus, which produces teicoplanin, and Streptomyces toyocaensis, which produces the A47934 glycopeptide. In this paper, we describe the natural and semi-synthetic glycopeptide antibiotics currently used as last resort drugs for Gram-positive infections and compare the van gene-based strategies of glycopeptide resistance among the pathogens and

  8. Reversing bacterial resistance to antibiotics by phage-mediated delivery of dominant sensitive genes.

    Science.gov (United States)

    Edgar, Rotem; Friedman, Nir; Molshanski-Mor, Shahar; Qimron, Udi

    2012-02-01

    Pathogen resistance to antibiotics is a rapidly growing problem, leading to an urgent need for novel antimicrobial agents. Unfortunately, development of new antibiotics faces numerous obstacles, and a method that resensitizes pathogens to approved antibiotics therefore holds key advantages. We present a proof of principle for a system that restores antibiotic efficiency by reversing pathogen resistance. This system uses temperate phages to introduce, by lysogenization, the genes rpsL and gyrA conferring sensitivity in a dominant fashion to two antibiotics, streptomycin and nalidixic acid, respectively. Unique selective pressure is generated to enrich for bacteria that harbor the phages carrying the sensitizing constructs. This selection pressure is based on a toxic compound, tellurite, and therefore does not forfeit any antibiotic for the sensitization procedure. We further demonstrate a possible way of reducing undesirable recombination events by synthesizing dominant sensitive genes with major barriers to homologous recombination. Such synthesis does not significantly reduce the gene's sensitization ability. Unlike conventional bacteriophage therapy, the system does not rely on the phage's ability to kill pathogens in the infected host, but instead, on its ability to deliver genetic constructs into the bacteria and thus render them sensitive to antibiotics prior to host infection. We believe that transfer of the sensitizing cassette by the constructed phage will significantly enrich for antibiotic-treatable pathogens on hospital surfaces. Broad usage of the proposed system, in contrast to antibiotics and phage therapy, will potentially change the nature of nosocomial infections toward being more susceptible to antibiotics rather than more resistant.

  9. Environmental factors influencing the development and spread of antibiotic resistance.

    Science.gov (United States)

    Bengtsson-Palme, Johan; Kristiansson, Erik; Larsson, D G Joakim

    2018-01-01

    Antibiotic resistance and its wider implications present us with a growing healthcare crisis. Recent research points to the environment as an important component for the transmission of resistant bacteria and in the emergence of resistant pathogens. However, a deeper understanding of the evolutionary and ecological processes that lead to clinical appearance of resistance genes is still lacking, as is knowledge of environmental dispersal barriers. This calls for better models of how resistance genes evolve, are mobilized, transferred and disseminated in the environment. Here, we attempt to define the ecological and evolutionary environmental factors that contribute to resistance development and transmission. Although mobilization of resistance genes likely occurs continuously, the great majority of such genetic events do not lead to the establishment of novel resistance factors in bacterial populations, unless there is a selection pressure for maintaining them or their fitness costs are negligible. To enable preventative measures it is therefore critical to investigate under what conditions and to what extent environmental selection for resistance takes place. In addition, understanding dispersal barriers is not only key to evaluate risks, but also to prevent resistant pathogens, as well as novel resistance genes, from reaching humans. © FEMS 2017.

  10. Zinc and copper in animal feed – development of resistance and co-resistance to antimicrobial agents in bacteria of animal origin

    Directory of Open Access Journals (Sweden)

    Siamak Yazdankhah

    2014-09-01

    Full Text Available Farmed animals such as pig and poultry receive additional Zn and Cu in their diets due to supplementing elements in compound feed as well as medical remedies. Enteral bacteria in farmed animals are shown to develop resistance to trace elements such as Zn and Cu. Resistance to Zn is often linked with resistance to methicillin in staphylococci, and Zn supplementation to animal feed may increase the proportion of multiresistant E. coli in the gut. Resistance to Cu in bacteria, in particular enterococci, is often associated with resistance to antimicrobial drugs like macrolides and glycopeptides (e.g. vancomycin. Such resistant bacteria may be transferred from the food-producing animals to humans (farmers, veterinarians, and consumers. Data on dose-response relation for Zn/Cu exposure and resistance are lacking; however, it seems more likely that a resistance-driven effect occurs at high trace element exposure than at more basal exposure levels. There is also lack of data which could demonstrate whether Zn/Cu-resistant bacteria may acquire antibiotic resistance genes/become antibiotics resistant, or if antibiotics-resistant bacteria are more capable to become Zn/Cu resistant than antibiotics-susceptible bacteria. Further research is needed to elucidate the link between Zn/Cu and antibiotic resistance in bacteria.

  11. Food and human gut as reservoirs of transferable antibiotic resistance encoding genes

    Directory of Open Access Journals (Sweden)

    Jean-Marc eRolain

    2013-06-01

    Full Text Available The increase and spread of antibiotic resistance (AR over the past decade in human pathogens has become a worldwide health concern. Recent genomic and metagenomic studies in humans, animals, in food and in the environment have led to the discovery of a huge reservoir of AR genes called the resistome that could be mobilized and transferred from these sources to human pathogens. AR is a natural phenomenon developed by bacteria to protect antibiotic-producing bacteria from their own products and also to increase their survival in highly competitive microbial environments. Although antibiotics are used extensively in humans and animals, there is also considerable usage of antibiotics in agriculture, especially in animal feeds and aquaculture. The aim of this review is to give an overview of the sources of AR and the use of antibiotics in these reservoirs as selectors for emergence of AR bacteria in humans via the food chain.

  12. Characterization of antibiotic resistant Escherichia coli in different poultry farming systems in the Eastern Province and Kigali City of Rwanda

    Directory of Open Access Journals (Sweden)

    R. Manishimwe

    2017-09-01

    Full Text Available Antibiotic resistance has become a global public health concern as a wide num­ber of resistant bacteria are continuously emerging. Animals have been pointed out as one of the sources of antibiotic-resistant bacteria that can be transferred to humans. To enrich the data on antibiotic resistance in animals in Rwanda, a cross-sectional study was carried out in the Eastern Province and in Kigali City to isolate Escherichia coli from free-range and commercial poultry farms. Fecal samples were collected from 294 poultry farms and E. coli strains were isolated and identified. In total 241 E. coli isolates were subjected to an antibi­otic sensitivity test using five antibiotics (gentamicin, streptomycin, rifampicin, doxycycline and erythromycin. Antibiotic use in poultry was low in free-range poultry farms (30.9% compared to layer and broiler production farms (100%. Among 151 farmers who reported using antibiotics in poultry, almost half (49.7% always used antibiotics with a veterinarian prescription. Out of 241 E. coli isolates, 43.2% had a multiple resistance to four of the five antibiotics tested. Almost all the isolates (98.8% were resistant to erythromycin, 78.8% were resistant to streptomycin, 77.6% were resistant to doxycycline, 69.3% were resistant to rifampicin and only a few were resistant to gentamicin (3.7%. No statistically significant difference was observed regarding isolate resistance against antibiotics according to the farming system type. However, resistance of isolates to doxycycline was significantly higher in farms where antibiotic use was reported (84% than in farms where antibiotic use was not reported (70%. The observed antibiotic resistance of E. coli shows the existence of a potential source of resistance that can be transferred to pathogenic bacteria and impact humans as well as animals.

  13. Characterization of Antibiotic Resistance Genes from Lactobacillus Isolated from Traditional Dairy Products.

    Science.gov (United States)

    Guo, Huiling; Pan, Lin; Li, Lina; Lu, Jie; Kwok, Laiyu; Menghe, Bilige; Zhang, Heping; Zhang, Wenyi

    2017-03-01

    Lactobacilli are widely used as starter cultures or probiotics in yoghurt, cheese, beer, wine, pickles, preserved food, and silage. They are generally recognized as safe (GRAS). However, recent studies have shown that some lactic acid bacteria (LAB) strains carry antibiotic resistance genes and are resistant to antibiotics. Some of them may even transfer their intrinsic antibiotic resistance genes to other LAB or pathogens via horizontal gene transfer, thus threatening human health. A total of 33 Lactobacillus strains was isolated from fermented milk collected from different areas of China. We analyzed (1) their levels of antibiotic resistance using a standardized dilution method, (2) their antibiotic resistance gene profiles by polymerase chain reaction (PCR) using gene-specific primers, and (3) the transferability of some of the detected resistance markers by a filter mating assay. All Lactobacillus strains were found to be resistant to vancomycin, but susceptible to gentamicin, linezolid, neomycin, erythromycin, and clindamycin. Their susceptibilities to tetracycline, kanamycin, ciprofloxacin, streptomycin, quinupristin/dalfopristin, trimethoprim, ampicillin, rifampicin, and chloramphenicol was different. Results from our PCR analysis revealed 19 vancomycin, 10 ciprofloxacin, and 1 tetracycline-resistant bacteria that carried the van(X), van(E), gyr(A), and tet(M) genes, respectively. Finally, no transferal of the monitored antibiotic resistance genes was observed in the filter mating assay. Taken together, our study generated the antibiotic resistance profiles of some milk-originated lactobacilli isolates and preliminarily assessed their risk of transferring antibiotic gene to other bacteria. The study may provide important data concerning the safe use of LAB. © 2017 Institute of Food Technologists®.

  14. Evidence for a complex relationship between antibiotics and antibiotic-resistant Escherichia coli: from medical center patients to a receiving environment.

    Science.gov (United States)

    Oberlé, Kenny; Capdeville, Marion-Justine; Berthe, Thierry; Budzinski, Hélène; Petit, Fabienne

    2012-02-07

    The aim of this study was to investigate the relationship between antibiotics and antibiotic-resistant fecal bacteria (E. coli) in water along a medical center-wastewater treatment plant-river continuum (4 km). A multiresidue chemical analysis methodology, using solid phase extraction coupled with liquid chromatography tandem mass spectrometry, was performed to detect whether low levels of contamination by 34 antibiotics were related to antibiotic resistance of E. coli and antibiotic use. The contamination of water by antibiotics and antibiotic-resistant E. coli decreased along the continuum. Although amoxicillin was predominantly prescribed, only ofloxacin (1 ng·L(-1)) and sulfamethoxazole (4 ng·L(-1)) persisted in the river. At the retirement home, in the medical center, even though no tetracycline and sulfamethoxazole were consumed, the highest occurrences of antibiotic resistance were in classes of quinolones (42.0%), sulfonamides (24.0%), tetracyclines (38.0%), and penicillins (38.0%), mainly due to the presence of multiple antibiotic-resistance genes on class 1 integrons. Along the continuum, the occurrence of E. coli resistant to antibiotics and those carrying class 1 integrons decreased in water samples (p-value antibiotic compounds (ofloxacin, sulfamethoxazole) were found, but they did not correspond to the major resistances (tetracycline, amoxicillin) of E. coli.

  15. Antibiotic resistance in the food chain: A developing country-perspective

    Directory of Open Access Journals (Sweden)

    Luria Leslie Founou

    2016-11-01

    Full Text Available Antibiotics are now endangered species facing extinction due to the worldwide emergence of antibiotic resistance (ABR. Food animals are considered as key reservoirs of antibiotic-resistant bacteria with the use of antibiotics in the food production industry having contributed to the actual global challenge of ABR. There are no geographic boundaries to impede the worldwide spread of ABR. If preventive and containment measures are not applied locally, nationally and regionally, the limited interventions in one country, continent and for instance, in the developing world, could compromise the efficacy and endanger ABR containment policies implemented in other parts of the world, the best-managed high-resource countries included. Multifaceted, comprehensive and integrated measures complying with the One Health approach are imperative to ensure food safety and security, effectively combat infectious diseases, curb the emergence and spread of ABR, and preserve the efficacy of antibiotics for future generations. Countries should follow the World Health Organization, World Organization for Animal Health, and the Food and Agriculture Organization of the United Nations recommendations to implement national action plans encompassing human, (food animal, and environmental sectors to improve policies, interventions and activities that address the prevention and containment of ABR from farm-to-fork. This review covers (i the origin of antibiotic resistance, (ii pathways by which bacteria spread to humans from farm-to-fork, (iii differences in levels of antibiotic resistance between developed and developing countries, and (iv prevention and containment measures of antibiotic resistance in the food chain.

  16. Antibiotic Resistance in the Food Chain: A Developing Country-Perspective.

    Science.gov (United States)

    Founou, Luria Leslie; Founou, Raspail Carrel; Essack, Sabiha Yusuf

    2016-01-01

    Antibiotics are now "endangered species" facing extinction due to the worldwide emergence of antibiotic resistance (ABR). Food animals are considered as key reservoirs of antibiotic-resistant bacteria with the use of antibiotics in the food production industry having contributed to the actual global challenge of ABR. There are no geographic boundaries to impede the worldwide spread of ABR. If preventive and containment measures are not applied locally, nationally and regionally, the limited interventions in one country, continent and for instance, in the developing world, could compromise the efficacy and endanger ABR containment policies implemented in other parts of the world, the best-managed high-resource countries included. Multifaceted, comprehensive, and integrated measures complying with the One Health approach are imperative to ensure food safety and security, effectively combat infectious diseases, curb the emergence and spread of ABR, and preserve the efficacy of antibiotics for future generations. Countries should follow the World Health Organization, World Organization for Animal Health, and the Food and Agriculture Organization of the United Nations recommendations to implement national action plans encompassing human, (food) animal, and environmental sectors to improve policies, interventions and activities that address the prevention and containment of ABR from farm-to-fork. This review covers (i) the origin of antibiotic resistance, (ii) pathways by which bacteria spread to humans from farm-to-fork, (iii) differences in levels of antibiotic resistance between developed and developing countries, and (iv) prevention and containment measures of antibiotic resistance in the food chain.

  17. A Review on Antibiotic Resistance: Alarm Bells are Ringing

    OpenAIRE

    Zaman, Sojib Bin; Hussain, Muhammed Awlad; Nye, Rachel; Mehta, Varshil; Mamun, Kazi Taib; Hossain, Naznin

    2017-01-01

    Antibiotics are the ?wonder drugs? to combat microbes. For decades, multiple varieties of antibiotics have not only been used for therapeutic purposes but practiced prophylactically across other industries such as agriculture and animal husbandry. Uncertainty has arisen, as microbes have become resistant to common antibiotics while the host remains unaware that antibiotic resistance has emerged. The aim of this review is to explore the origin, development, and the current state of antibiotic ...

  18. Inactivation Effect of Antibiotic-Resistant Gene Using Chlorine Disinfection

    Directory of Open Access Journals (Sweden)

    Takashi Furukawa

    2017-07-01

    Full Text Available The aim of this study was to elucidate the inactivation effects on the antibiotic-resistance gene (vanA of vancomycin-resistant enterococci (VRE using chlorination, a disinfection method widely used in various water treatment facilities. Suspensions of VRE were prepared by adding VRE to phosphate-buffered saline, or the sterilized secondary effluent of a wastewater treatment plant. The inactivation experiments were carried out at several chlorine concentrations and stirring time. Enterococci concentration and presence of vanA were determined. The enterococci concentration decreased as chlorine concentrations and stirring times increased, with more than 7.0 log reduction occurring under the following conditions: 40 min stirring at 0.5 mg Cl2/L, 20 min stirring at 1.0 mg Cl2/L, and 3 min stirring at 3.0 mg Cl2/L. In the inactivation experiment using VRE suspended in secondary effluent, the culturable enterococci required much higher chlorine concentration and longer treatment time for complete disinfection than the cases of suspension of VRE. However, vanA was detected in all chlorinated suspensions of VRE, even in samples where no enterococcal colonies were present on the medium agar plate. The chlorine disinfection was not able to destroy antibiotic-resistance genes, though it can inactivate and decrease bacterial counts of antibiotic-resistant bacteria (ARB. Therefore, it was suggested that remaining ARB and/or antibiotic-resistance gene in inactivated bacterial cells after chlorine disinfection tank could be discharged into water environments.

  19. Characterization of Bacteria in Nigerian Yogurt as Promising Alternative to Antibiotics in Gastrointestinal Infections.

    Science.gov (United States)

    Ayeni, Anthony Opeyemi; Ruppitsch, Werner; Ayeni, Funmilola Abidemi

    2018-03-14

    Gastrointestinal infections are endemic in Nigeria and several factors contribute to their continual survival, including bacterial resistance to commonly used antibiotics. Nigerian yogurts do not include probiotics, and limited information is available about the antimicrobial properties of the fermenters in the yogurt against gastrointestinal pathogens. Therefore, the antimicrobial potentials of bacteria in Nigeria-produced yogurts against intestinal pathogens were investigated in this study. Viable counts of lactic acid bacteria (LAB) in 15 brands of yogurt were enumerated and the bacteria identified by partial sequencing of 16S rRNA gene. Susceptibility of the gastrointestinal pathogens (Salmonella, Shigella and E. coli ) to antibiotics by disc diffusion method, to viable LAB by the agar overlay method, and to the cell-free culture supernatant (CFCS) of the LAB were investigated. Co-culture analysis of LAB and pathogens were also done. Viable counts of 1.5 × 10 11 cfu/ml were observed in some yogurt samples. Two genera were identified: Lactobacillus (70.7%) and Acetobacter (29.3%). The Lactobacillus species reduced multidrug-resistant gastrointestinal pathogens by 4 to 5 log while the zones of inhibition ranged between 11 and 23. The Lactobacillus and Acetobacter strains examined displayed good activities against the multidrug-resistant tested pathogens. This is the first report of antimicrobial activities of acetic acid bacteria isolated from yogurt in Nigeria.

  20. Optimization of treatment protocols to prevent de novo development of antibiotic resistance in Pseudomonas aeruginosa

    NARCIS (Netherlands)

    Feng, Yanfang

    2016-01-01

    The ever-increasing rate of drug resistant bacteria has been one of the most challenging problem worldwide. This thesis studied the following subjects with mostly the clinically leading pathogen, P. aeruginosa, as the model strain: de novo development of antibiotic resistance in patient during the

  1. The etiology of neonatal sepsis and patterns of antibiotic resistance

    International Nuclear Information System (INIS)

    Waheed, M.; Laeeq, A.; Maqbool, S.

    2003-01-01

    Objective: To study the patterns of causative bacteria and antibiotic resistance in neonatal sepsis. Results: Among 228 cases included in the study, the male to female ratio was 2.1 to 1. The gestational age was less than 36 weeks in 68 (30%) cases and low birth weight babies were 143 (62.6%). History of birth asphyxia was present in 103 (45%) cases. There were 142 (62.3%) cases of early onset ( 7 days). Out of 233 positive blood cultures Escherichia coli was found to be commonest (47.8%, n =111, p<0.05) both in early onset (47.8%, n=68, p <0.05) and late onset sepsis (47.3%,n=43, p<0.05). Staphylococcus aureus was the most common among gram positive organism. Resistance to cefotaxime, ceftazidime and amikacin was 34% to 80% and to ciprofloxacin 13% to 72%. A total of 64 cases (28%) died. Mortality was four times higher in early onset sespis. Conclusion: Gram negative bacteria are the commenst cause of neonatal sepsis. The resistance to the commonly used antibiotics is alarmingly high. Mortality is four times higher in early one set sepsis. (author)

  2. [Antibiotic resistance of important infection sources in 1996 in Weser-Ems].

    Science.gov (United States)

    Klarmann, D

    1997-08-01

    An overview of the antibiotic resistance of important bacteria of infectious disease in 1996 in the district of Weser-Ems in Lower Sexonie among farm animals, dogs and cats is given. The bacteria isolated from different materials as animal body, organ, droppings, milk, swabs from nose, cervix or other source and their resistance pattern were listed belonging to species and localisation of their isolation. By means of different counts of isolation one can see the importance of the isolated bacteria at the ITT, Institut für Tierzucht, Tierhaitung und Tiergesundheit, of the Landwirtschaftskammer Weser-Ems in Oldenburg. The development of resistance of bacteria obtained from dairy cows with mastitis and in general some important antibiotics like cefoperazon, ceftiofur and enrofloxacine is shown. Furthermore more detailed instructions to the method of microbiological resistance testing, the broth microdilution method, are given.

  3. Self-resistance in Streptomyces, with Special Reference to β-Lactam Antibiotics.

    Science.gov (United States)

    Ogawara, Hiroshi

    2016-05-10

    Antibiotic resistance is one of the most serious public health problems. Among bacterial resistance, β-lactam antibiotic resistance is the most prevailing and threatening area. Antibiotic resistance is thought to originate in antibiotic-producing bacteria such as Streptomyces. In this review, β-lactamases and penicillin-binding proteins (PBPs) in Streptomyces are explored mainly by phylogenetic analyses from the viewpoint of self-resistance. Although PBPs are more important than β-lactamases in self-resistance, phylogenetically diverse β-lactamases exist in Streptomyces. While class A β-lactamases are mostly detected in their enzyme activity, over two to five times more classes B and C β-lactamase genes are identified at the whole genomic level. These genes can subsequently be transferred to pathogenic bacteria. As for PBPs, two pairs of low affinity PBPs protect Streptomyces from the attack of self-producing and other environmental β-lactam antibiotics. PBPs with PASTA domains are detectable only in class A PBPs in Actinobacteria with the exception of Streptomyces. None of the Streptomyces has PBPs with PASTA domains. However, one of class B PBPs without PASTA domain and a serine/threonine protein kinase with four PASTA domains are located in adjacent positions in most Streptomyces. These class B type PBPs are involved in the spore wall synthesizing complex and probably in self-resistance. Lastly, this paper emphasizes that the resistance mechanisms in Streptomyces are very hard to deal with, despite great efforts in finding new antibiotics.

  4. Assessing the Risk of Probiotic Dietary Supplements in the Context of Antibiotic Resistance

    Directory of Open Access Journals (Sweden)

    Min Zheng

    2017-05-01

    Full Text Available Probiotic bacteria are known to harbor intrinsic and mobile genetic elements that confer resistance to a wide variety of antibiotics. Their high amounts in dietary supplements can establish a reservoir of antibiotic resistant genes in the human gut. These resistant genes can be transferred to pathogens that share the same intestinal habitat thus resulting in serious clinical ramifications. While antibiotic resistance of probiotic bacteria from food, human and animal sources have been well-documented, the resistant profiles of probiotics from dietary supplements have only been recently studied. These products are consumed with increasing regularity due to their health claims that include the improvement of intestinal health and immune response as well as prevention of acute and antibiotic-associated diarrhea and cancer; but, a comprehensive risk assessment on the spread of resistant genes to human health is lacking. Here, we highlight recent reports of antibiotic resistance of probiotic bacteria isolated from dietary supplements, and propose complementary strategies that can shed light on the risks of consuming such products in the context of a global widespread of antibiotic resistance. In concomitant with a broader screening of antibiotic resistance in probiotic supplements is the use of computational simulations, live imaging and functional genomics to harvest knowledge on the evolutionary behavior, adaptations and dynamics of probiotics studied in conditions that best represent the human gut including in the presence of antibiotics. The underlying goal is to enable the health benefits of probiotics to be exploited in a responsible manner and with minimal risk to human health.

  5. NOVEL ANTIBIOTIC RESISTANCE DETERMINANTS FROM AGRICULTURAL SOIL EXPOSED TO ANTIBIOTICS WIDELY USED IN HUMAN MEDICINE AND ANIMAL FARMING.

    Science.gov (United States)

    Lau, Calvin Ho-Fung; van Engelen, Kalene; Gordon, Stephen; Renaud, Justin; Topp, Edward

    2017-06-16

    Antibiotic resistance has emerged globally as one of the biggest threats to human and animal health. Although the excessive use of antibiotics is recognized for accelerating the selection for resistance, there is a growing body of evidence suggesting that natural environments are "hotspots" for the development of both ancient and contemporary resistance mechanisms. Given that pharmaceuticals can be entrained onto agricultural land through anthropogenic activities, this could be a potential driver for the emergence and dissemination of resistance in soil bacteria. Using functional metagenomics, we interrogated the "resistome" of bacterial communities found in a collection of Canadian agricultural soil, some of which had been receiving antibiotics widely used in human medicine (macrolides) or food animal production (sulfamethazine, chlortetracycline and tylosin) for up to 16 years. Of the 34 new antibiotic resistance genes (ARGs) recovered, the majority were predicted to encode for (multi)drug efflux systems, while a few share little to no homology with established resistance determinants. We characterized several novel gene products, including putative enzymes that can confer high-level resistance against aminoglycosides, sulfonamides, and broad range of beta-lactams, with respect to their resistance mechanisms and clinical significance. By coupling high-resolution proteomics analysis with functional metagenomics, we discovered an unusual peptide, PPP AZI 4 , encoded within an alternative open-reading frame not predicted by bioinformatics tools. Expression of the proline-rich PPP AZI 4 can promote resistance against different macrolides but not other ribosomal-targeting antibiotics, implicating a new macrolide-specific resistance mechanism that could be fundamentally linked to the evolutionary design of this peptide. IMPORTANCE Antibiotic resistance is a clinical phenomenon with an evolutionary link to the microbial pangenome. Genes and protogenes encoding for

  6. Antibiotic resistance of microbial contaminations isolated from husbandry animals and foodstuffs

    Directory of Open Access Journals (Sweden)

    Lukáš Hleba

    2014-05-01

    Full Text Available In this paper the antibiotic resistance of microbial contaminations isolated from husbandry animals and foodstuffs were investigated. Microorganisms isolated from animals and foodstuffs were contaminations of selective media as MacConkey agar for Enterobacteriaceae genera and MRS agar for lactobacilli strains. Microorganisms were isolated and puryfied by agar four ways streak plate method. Identification of isolated microorganisms was done by mass-spectrometry method in MALDI-TOF MS Biotyper. For investigation of antibiotic resistance disc diffusion method by EUCAST was used. In this study Gram-negative and Gram-positive bacteria were identified. The most resistant or multi-resistant bacteria as Pseudomonas aeruginosa, Acinetobacter lwoffi, Lysinibacillus sphaericus, Staphylococcus aureus and Staphylococcus epidermis were determined. Other identified microorganisms were resistant to one antibiotic or not at all.

  7. Current trends of human infections and antibiotic resistance of the genus Shewanella.

    Science.gov (United States)

    Yousfi, K; Bekal, S; Usongo, V; Touati, A

    2017-08-01

    Shewanella spp. are commonly known as environmental bacteria and are most frequently isolated from aquatic areas. Currently, diseases syndromes and multidrug resistance have increasingly been reported in the genus Shewanella. Some species are associated with various infections, such as skin and soft tissue infections, as well as bacteremia. Generally, these bacteria are opportunistic and mostly affect people with an impaired immune system. This genus is also a probable vehicle and progenitor of antibiotic resistance genes. In fact, several resistance genes and mobile genetic elements have been identified in some resistant species isolated from environmental or clinical settings. These genes confer resistance to different antibiotic classes, including those used in therapies such as β-lactams and quinolones, and are generally located on the chromosome. Recently, a multidrug-resistant (MDR) plasmid harboring several drug resistance genes associated with transposons and integrons has been identified in Shewanella xiamenensis. These antibiotic resistance genes can circulate in the environment and contribute to the emergence of antibiotic resistance. This review describes different aspects of Shewanella, focusing on the infections caused by this genus, as well as their role in the propagation of antibiotic resistance via mobile genetic elements.

  8. Microbial pollution in wildlife: Linking agricultural manuring and bacterial antibiotic resistance in red-billed choughs.

    Science.gov (United States)

    Blanco, Guillermo; Lemus, Jesús A; Grande, Javier

    2009-05-01

    The spread of pathogens in the environment due to human activities (pathogen pollution) may be involved in the emergence of many diseases in humans, livestock and wildlife. When manure from medicated livestock and urban effluents is spread onto agricultural land, both residues of antibiotics and bacteria carrying antibiotic resistance may be introduced into the environment. The transmission of bacterial resistance from livestock and humans to wildlife remains poorly understood even while wild animals may act as reservoirs of resistance that may be amplified and spread in the environment. We determined bacterial resistance to antibiotics in wildlife using the red-billed chough Pyrrhocorax pyrrhocorax as a potential bioindicator of soil health, and evaluated the role of agricultural manuring with waste of different origins in the acquisition and characteristics of such resistance. Agricultural manure was found to harbor high levels of bacterial resistance to multiple antibiotics. Choughs from areas where manure landspreading is a common agricultural practice harbor a high bacterial resistance to multiple antibiotics, resembling the resistance profile found in the waste (pig slurry and sewage sludge) used in each area. The transfer of bacterial resistance to wildlife should be considered as an important risk for environmental health when agricultural manuring involves fecal material containing multiresistant enteric bacteria including pathogens from livestock operations and urban areas. The assessment of bacterial resistance in wild animals may be valuable for the monitoring of environmental health and for the management of emergent infectious diseases influenced by the impact of different human activities in the environment.

  9. The prevalence of pathogenic bacteria and antimicrobial resistance in milk of Ettawa Grade goat

    Directory of Open Access Journals (Sweden)

    A. Andriani

    2018-05-01

    Full Text Available Ettawa Grade (PE are potentially developed goats to produce milk and meat. Milk is food of animal that is rich in nutrients, but it is a perishable food easily contaminated by microorganisms. Contaminated pathogenic bacteria in milk can decrease the quality and has an organoleptic effect on milk, as well as endangers human health. Milk contaminated with bacteria antimicrobial resistance (AMR in which is resistant to antibiotics, may adversely affect the response to treatment with antibiotics in humans when suffering from infectious diseases and using antibiotics in therapy. In this study Ettawa Grade's samples of fresh milk and other dairy products were taken from some of the goat farms in Yogyakarta Sleman district. The samples were tested for the presence of pathogenic bacteria and for its resistance to several kinds of antibiotics. In this study 35 Ettawa Grade's samples of fresh milk and other dairy products (fresh milk, milk powder, ice cream, and yoghurt were taken from some of the goat farms in Sleman district-Yogyakarta. The samples were tested for the presence of pathogenic bacteria and for its resistance to several kinds of antibiotics. The result of the prevalence of pathogenic bacteria in goat fresh milk and other dairy products was 15% Escherichia coli and had multi resistance to multiple antibiotics, namely ampicillin, colistin sulphate, cefixime, kanamycin, oxytetracycline, tetracycline and sulfonamide.

  10. Potentiating antibiotics in drug-resistant clinical isolates via stimuli-activated superoxide generation.

    Science.gov (United States)

    Courtney, Colleen M; Goodman, Samuel M; Nagy, Toni A; Levy, Max; Bhusal, Pallavi; Madinger, Nancy E; Detweiler, Corrella S; Nagpal, Prashant; Chatterjee, Anushree

    2017-10-01

    The rise of multidrug-resistant (MDR) bacteria is a growing concern to global health and is exacerbated by the lack of new antibiotics. To treat already pervasive MDR infections, new classes of antibiotics or antibiotic adjuvants are needed. Reactive oxygen species (ROS) have been shown to play a role during antibacterial action; however, it is not yet understood whether ROS contribute directly to or are an outcome of bacterial lethality caused by antibiotics. We show that a light-activated nanoparticle, designed to produce tunable flux of specific ROS, superoxide, potentiates the activity of antibiotics in clinical MDR isolates of Escherichia coli , Salmonella enterica , and Klebsiella pneumoniae . Despite the high degree of antibiotic resistance in these isolates, we observed a synergistic interaction between both bactericidal and bacteriostatic antibiotics with varied mechanisms of action and our superoxide-producing nanoparticles in more than 75% of combinations. As a result of this potentiation, the effective antibiotic concentration of the clinical isolates was reduced up to 1000-fold below their respective sensitive/resistant breakpoint. Further, superoxide-generating nanoparticles in combination with ciprofloxacin reduced bacterial load in epithelial cells infected with S. enterica serovar Typhimurium and increased Caenorhabditis elegans survival upon infection with S. enterica serovar Enteriditis, compared to antibiotic alone. This demonstration highlights the ability to engineer superoxide generation to potentiate antibiotic activity and combat highly drug-resistant bacterial pathogens.

  11. Metagenomic frameworks for monitoring antibiotic resistance in aquatic environments.

    Science.gov (United States)

    Port, Jesse A; Cullen, Alison C; Wallace, James C; Smith, Marissa N; Faustman, Elaine M

    2014-03-01

    High-throughput genomic technologies offer new approaches for environmental health monitoring, including metagenomic surveillance of antibiotic resistance determinants (ARDs). Although natural environments serve as reservoirs for antibiotic resistance genes that can be transferred to pathogenic and human commensal bacteria, monitoring of these determinants has been infrequent and incomplete. Furthermore, surveillance efforts have not been integrated into public health decision making. We used a metagenomic epidemiology-based approach to develop an ARD index that quantifies antibiotic resistance potential, and we analyzed this index for common modal patterns across environmental samples. We also explored how metagenomic data such as this index could be conceptually framed within an early risk management context. We analyzed 25 published data sets from shotgun pyrosequencing projects. The samples consisted of microbial community DNA collected from marine and freshwater environments across a gradient of human impact. We used principal component analysis to identify index patterns across samples. We observed significant differences in the overall index and index subcategory levels when comparing ecosystems more proximal versus distal to human impact. The selection of different sequence similarity thresholds strongly influenced the index measurements. Unique index subcategory modes distinguished the different metagenomes. Broad-scale screening of ARD potential using this index revealed utility for framing environmental health monitoring and surveillance. This approach holds promise as a screening tool for establishing baseline ARD levels that can be used to inform and prioritize decision making regarding management of ARD sources and human exposure routes. Port JA, Cullen AC, Wallace JC, Smith MN, Faustman EM. 2014. Metagenomic frameworks for monitoring antibiotic resistance in aquatic environments. Environ Health Perspect 122:222–228; http://dx.doi.org/10.1289/ehp

  12. Management options for reducing the release of antibiotics and antibiotic resistance genes to the environment

    DEFF Research Database (Denmark)

    Pruden, Amy; Larsson, D.G. Joakim; Amézquita, Alejandro

    2013-01-01

    Background: There is growing concern worldwide about the role of polluted soil and water environments in the development and dissemination of antibiotic resistance. Objective: Our aim in this study was to identify management options for reducing the spread of antibiotics and antibiotic resistance...

  13. Association of Antibiotic Resistance in Agricultural Escherichia coli Isolates with Attachment to Quartz▿

    Science.gov (United States)

    Liu, Ping; Soupir, Michelle L.; Zwonitzer, Martha; Huss, Bridgette; Jarboe, Laura R.

    2011-01-01

    Surface water can be contaminated by bacteria from various sources, including manure from agricultural facilities. Attachment of these bacteria to soil and organic particles contributes to their transport through the environment, though the mechanism of attachment is unknown. As bacterial attachment to human tissues is known to be correlated with antibiotic resistance, we have investigated here the relationship between bacterial attachment to environmental particles and antibiotic resistance in agricultural isolates. We evaluated 203 Escherichia coli isolates collected from swine facilities for attachment to quartz, resistance to 13 antibiotics, and the presence of genes encoding 13 attachment factors. The genes encoding type I, EcpA, P pili, and Ag43 were detected, though none was significantly related to attachment. Quartz attachment was positively and significantly (P amoxicillin/streptomycin/tetracycline/sulfamethazine/tylosin/chlortetracycline and negatively and significantly (P < 0.0038) related to combined resistance to nalidixic acid/kanamycin/neomycin. These results provide clear evidence for a link between antibiotic resistance and attachment to quartz in agricultural isolates. We propose that this may be due to encoding by the responsible genes on a mobile genetic element. Further exploration of the relationship between antibiotic resistance and attachment to environmental particles will improve the understanding and modeling of environmental transport processes, with the goal of preventing human exposure to antibiotic-resistant or virulent microorganisms. PMID:21821756

  14. Association of antibiotic resistance in agricultural Escherichia coli isolates with attachment to quartz.

    Science.gov (United States)

    Liu, Ping; Soupir, Michelle L; Zwonitzer, Martha; Huss, Bridgette; Jarboe, Laura R

    2011-10-01

    Surface water can be contaminated by bacteria from various sources, including manure from agricultural facilities. Attachment of these bacteria to soil and organic particles contributes to their transport through the environment, though the mechanism of attachment is unknown. As bacterial attachment to human tissues is known to be correlated with antibiotic resistance, we have investigated here the relationship between bacterial attachment to environmental particles and antibiotic resistance in agricultural isolates. We evaluated 203 Escherichia coli isolates collected from swine facilities for attachment to quartz, resistance to 13 antibiotics, and the presence of genes encoding 13 attachment factors. The genes encoding type I, EcpA, P pili, and Ag43 were detected, though none was significantly related to attachment. Quartz attachment was positively and significantly (P amoxicillin/streptomycin/tetracycline/sulfamethazine/tylosin/chlortetracycline and negatively and significantly (P < 0.0038) related to combined resistance to nalidixic acid/kanamycin/neomycin. These results provide clear evidence for a link between antibiotic resistance and attachment to quartz in agricultural isolates. We propose that this may be due to encoding by the responsible genes on a mobile genetic element. Further exploration of the relationship between antibiotic resistance and attachment to environmental particles will improve the understanding and modeling of environmental transport processes, with the goal of preventing human exposure to antibiotic-resistant or virulent microorganisms.

  15. DEVELOPMENT OF RESISTANCE IN BACTERIA AGAINST ANTI - MICROBIAL AGENTS: REASONS, THREATS AND ONGOING ENCOUNTER

    Directory of Open Access Journals (Sweden)

    Shibabrata Pattanayak

    2011-07-01

    Full Text Available Development of Multi Druug Resistant bacteria is creating a very severe problem in anti-microbial chemotherapy. Many recently developed antibiotics are found incapable to control resistant organisms.The reasons of development of resistance gene in the bacterial plasmid and their quick spread among various related and unrelated bacteria are analysed in this article along with discussion of world wide ongoing research to combat the problem.

  16. DEVELOPMENT OF RESISTANCE IN BACTERIA AGAINST ANTI - MICROBIAL AGENTS: REASONS, THREATS AND ONGOING ENCOUNTER

    OpenAIRE

    Shibabrata Pattanayak

    2011-01-01

    Development of Multi Druug Resistant bacteria is creating a very severe problem in anti-microbial chemotherapy. Many recently developed antibiotics are found incapable to control resistant organisms.The reasons of development of resistance gene in the bacterial plasmid and their quick spread among various related and unrelated bacteria are analysed in this article along with discussion of world wide ongoing research to combat the problem.

  17. Transport and transformation of genetic information in the critical zone: The case of antibiotic resistance genes

    Science.gov (United States)

    Zhu, Y. G.

    2015-12-01

    In addition to material and energy flows, the dynamics and functions of the Earth's critical zone are intensively mediated by biological actions performed by diverse organisms. These biological actions are modulated by the expression of functional genes and their translation into enzymes that catalyze geochemical reactions, such as nutrient turnover and pollutant biodegradation. Although geobiology, as an interdisciplinary research area, is playing and vital role in linking biological and geochemical processes at different temporal and spatial scales, the distribution and transport of functional genes have rarely been investigated from the Earth's critical zone perspectives. To illustrate the framework of studies on the transport and transformation of genetic information in the critical zone, antibiotic resistance is taken as an example. Antibiotic resistance genes are considered as a group of emerging contaminants, and their emergence and spread within the critical zone on one hand are induced by anthropogenic activities, and on other hand are threatening human health worldwide. The transport and transformation of antibiotic resistance genes are controlled by both horizontal gene transfer between bacterial cells and the movement of bacteria harboring antibiotic resistance genes. In this paper, the fate and behavior of antibiotic resistance genes will be discussed in the following aspects: 1) general overview of environmental antibiotic resistance; 2) high through quantification of the resistome in various environmental media; 3) pathways of resistance gene flow within the critical zone; and 4) potential strategies in mitigating antibiotic resistance, particularly from the critical zone perspectives.

  18. Microbial resistance to antibiotics | Chinedum | African Journal of ...

    African Journals Online (AJOL)

    Organisms that are normally sensitive to the action of an antibiotic may sometimes develop resistance or insensitivity to it. This, they may do through destroying the antibiotic or by retaining their growth even in the presence of the drug. Microbial resistance to antibiotics is now widespread and poses a serious clinical threat.

  19. Antibiotic resistance status of Escherichia coli isolated from healthy ...

    African Journals Online (AJOL)

    The research revealed a high level of antibiotic resistance among E. coli. The percentage of resistance observed for the antibiotics included in this study reflected the degree of their respective uses in pig production in the study area. This work further supports the need for prudent use of each of the antibiotics in animal ...

  20. Antibiotic and synergistic effect of Leu-Lys rich peptide against antibiotic resistant microorganisms isolated from patients with cholelithiasis.

    Science.gov (United States)

    Jeong, Nari; Kim, Jin-Young; Park, Seong-Cheol; Lee, Jong-Kook; Gopal, Ramamourthy; Yoo, Suyeon; Son, Byoung Kwan; Hahm, Joon Soo; Park, Yoonkyung; Hahm, Kyung-Soo

    2010-09-03

    Pseudomonas aeruginosa has eventually developed resistance against flomoxef sodium, isepamicin and cefpiramide. Therefore, in this study, the antibacterial activity and synergistic effects of the amphipathic-derived P5-18mer antimicrobial peptide were tested against pathogens associated with cholelithiasis that have developed resistance against commonly used antibiotics. The results were then compared with the activities of the amphipathic-derived peptide, P5-18mer, melittin and common antibiotics. Growth inhibition of planktonic bacteria was tested using the National Committee for Clinical Laboratory Standards (NCCLS). The bactericidal activity of the antimicrobial peptides was measured using time-kill curves. Synergistic effects were evaluated by testing the effects of P5-18mer alone and in combination with flomoxef sodium, isepamicin or cefpiramide at 0.5xMIC. P5-18mer peptide displayed strong activity against pathogens and flomoxef sodium, isepamicin and cefpiramide-resistant bacteria cell lines obtained from a patient with gallstones; however, it did not exert cytotoxicity against the human keratinocyte HaCat cell line. In addition, the results of time-kill curves indicated that P5-18mer peptide exerted bactericidal activity against four strains of P. aeruginosa. Finally, the use of P5-18mer and antibiotics exerted synergistic effects against cell lines that were resistant to commonly used antibiotics. These results indicate that this class of peptides has a rapid microbicidal effect on flomoxef sodium, isepamicin and cefpiramide-resistant strains of P. aeruginosa. Therefore, these peptides may be used as a lead drug for the treatment of acquired pathogens from patients with cholelithiasis who are affected with antibiotic-resistant bacteria. Copyright 2010 Elsevier Inc. All rights reserved.

  1. Antibiotic resistance: current issues and future strategies

    Directory of Open Access Journals (Sweden)

    Giancarlo Scarafile

    2016-09-01

    Full Text Available The antibiotic resistance (antimicrobial resistance – AMR and the particular emergence of multi-resistant bacterial strains, is a problem of clinical relevance involving serious threats to public health worldwide. From early this decade, a lot of studies have demonstrated a significant increase in the rates of antibiotic resistance by bacterial pathogens responsible for nosocomial and community infections all over the world. The AMR leads to a reduced drug efficacy in the treatment options available and therefore, to an increase in mortality rates. The original causes of the phenomenon are: environmental factors which favor a mutation of the genetic bacterial inheritance, thereby inhibiting the active ingredient of the antibiotics; unsuitable administering of antibiotics in veterinary, incorrect taking both in hospitals and at home and, lately, lack of investments in the development of new drugs. The alarming epidemiological data prompted the World Health Organization (WHO in 2011 to coin the slogan "No action today, no cure tomorrow" in order to immediately implement a new strategy to improve the use of available drugs and to accelerate the introduction of new ones through a new phase of research invo