Incidence Of Antibiotic-resistant Bacteria Research Articles

Antibiotic Resistant Escherichia coli Isolated from Faecal Samples of Cow at Livestock Farm in Kedah, Malaysia

Introduction: Escherichia coli is a typical microflora found in the intestines of livestock, but regular exposure to antibiotics puts them under selection pressure to acquire antibiotic resistance. This study aimed to identify and characterise the antibiotic resistance profile of E. coli isolated in cow faeces collected from Tobiar Modern farm located in Kedah, Malaysia. Materials and methods: The antibiotic susceptibility test (AST) was conducted to assess the sensitivity of E. coli isolates to tetracycline (30 µg/mL), erythromycin (15 µg/mL) and ampicillin (10 µg/mL) using disk diffusion method followed by Minimum Inhibitory Concentration (MIC) assay. For molecular identification of selected resistant isolates, 16S rDNA gene sequencing was carried out. Results: Six (Isolates A1, P1, P2, P3, P4, and P5) out of 30 isolates were identified as E. coli based on their colonial morphological characteristics. The tests for catalase, indole, MR, TSI, and lactose fermentation all yielded positive results for the isolates, whereas the tests for oxidase, citrate, and VP yielded negative results. All six isolates were found to be erythromycin resistant. The Isolate P4 was observed as a multidrug resistant (MDR) bacterial strain since it exhibited resistance to all tested antibiotics. The MDR Isolate P4 is identified as E. coli strain LWY24 using molecular identification with a 99.7% identity rate. Conclusion: This study offers important preliminary information on the incidence of antibiotic-resistant bacteria (ARB) on this particular local livestock farm. This data is useful for developing plans to reduce the prevalence of ARB in livestock.

Incidence of Antibiotic Resistant Bacteria In Fish Sold In Local Market In Dhaka City

Present study was designed to evaluate the microbial contamination in fish (Olive Barb, Bele, Pale-Carplet, Pabo Catfish, Olive, Tangra, Gizzard, Nola, Tatkini, Corica Soborna) samples were collected from the several local market of Dhaka city, Bangladesh. Most of the fish samples were found to be contaminated with huge number of micro-biota within the range of 105 to 106 CFU/g. The maximum total viable bacterial (TVB) load was estimated observed in Pale Carplet (Amblypharyngodon mola) (4.8×106 CFU/g) and the lowest count was found (1.5×105 CFU/g) in tangra (Mystus spp.) Escherichia coli and Klebsiella spp. were present in olive barb, bele, tangra and gizzard while Salmonella spp. and Vibrio spp. were present in olive barb, bele, tangra and gizzard fish samples. Moreover, most of the isolated bacteria exhibited resistance against maximum antibiotics like trimethoprime/sulfamethoxazole (25 μg), erythromycin (15 μg), amoxicillin (30 μg), Ceftriaxon (30 μg), ciprofloxacin (5 μg), streptomycin (10 μg), Ampicillin (10 μg). Microbial contamination in the fish samples especially those were resistant to drugs may pose a serious threat to public health.
 Stamford Journal of Microbiology, 2023. Vol. 13, Issue 1, p. 38-41

Incidence of Antibiotic Resistant Bacteria in Poultry and Livestock in Dhaka City

Antimicrobial resistance is a concern for humans and animals all over the world. Indiscriminate use of antibiotics in livestock and poultry has become one of the major causes of antimicrobial resistance development in microorganisms. The aim of the study was to determine the antimicrobial resistance patterns of bacteria isolated from raw meat, intestine, feces and feed of farm chicken, cow and local chicken. Samples were collected from different retail shops at Malibagh area in Dhaka City, Bangladesh. Bacterial load was enumerated, potentially pathogenic bacteria were identified and antibiogram was determined following standard methods. A total of 43 bacterial isolates were identified from different samples which were Escherichia coli, Enterobacter, Citrobacter, Klebsiella, Providencia and Acinetobacter spp. Eight types of antibiotics such as, Ampicillin-10μg, Gentamicin-10μg, Amikacin-10μg, Amoxicillin-10μg, Ceftriaxone-30μg, Imipenem-10μg, Chloramphenicol-30μg and Tetracycline-30μg were used to determine the antibiotic sensitivity pattern of isolated bacteria. The antibiotic resistance pattern of bacteria isolated from feed and feces samples of cow and chicken were found to be similar. Isolated bacteria from chicken meats showed higher antimicrobial resistance (80-100%) against Ampicillin-10μg, Imipenem-10μg and Amoxicillin-10μg compared to cow meat isolates. The incidence of antibiotic resistant bacteria is a threat to animals, food handlers and consumers if they are being infected by these antibiotic resistant pathogenic bacteria. Stamford Journal of Microbiology, Vol.12 (1) 2022: 37-42

Effects of Nano Zinc on Growth Performance, Health Status, and Cecal Microbiota in Broiler Chickens Challenged with Salmonella Kentucky

Public concern with the incidence of antibiotic-resistant bacteria, particularly among foodborne pathogens, such as Salmonella, has been challenging the poultry industry to find alternative means of control. The present study was conducted to investigate the effect of dietary replacement of inorganic zinc oxide (ZnO) by different levels of zinc nanoparticles on growth performance, blood serum biochemical changes, immune response, cecal microbiota, and some internal organs histopathology of Salmonella Kentucky (SK) challenged broiler chickens. A total of 180 one-day-old broiler chicks were used in the present experiment. The chicks were randomly allotted into six equal groups (30 chicks/group), with 3 subgroups containing 10 chicks as a replicate. The first group fed on the basal diet supplemented by 100 mg ZnO/kg diet, while the second and the third groups fed on the basal diet with replacement of ZnO by 100 and 50 mg of zinc oxide nanoparticles (ZnONPs)/kg diet, respectively. Moreover, the fourth, fifth, and sixth groups fed as the first three groups with SK challenge on the third day of age. Results showed that supplementation of 100 mg ZnONPs/kg diet instead of ZnO reduced the severity of the clinical signs, post-mortem lesions, mortality, and SK fecal shedding of SK challenged chicks. Replacement of ZnO by 100% or 50% of ZnONPs increased cecal total bacterial counts and lactobacillus bacterial count while reducing total coliform counts. On the other hand, the SK challenge increased cecal total bacterial counts and lactobacillus bacterial counts, compared to the broiler chicks group fed on the diet without SK challenge. The SK challenge with inorganic zinc addition reduced body gain and feed conversion ratio, while 100 or 50 mg ZnONPs/kg diet supplementation instead of ZnO improved growth performance, feed efficiency parameters. It was observed that the replacement of inorganic zinc (serum ZnO) by 100 mg /kg diet significantly increased lysosomal and phagocytic activity by about 261.5% and 17.9%, respectively. Moreover, 100% or 50% of ZnONPs instead of inorganic zinc significantly ZnONPs increased liver, spleen, and thymus gland relative weights of SK-challenged broiler chickens, compared to broiler chickens group fed on the same diet without challenge or compared to chicks group fed on ZnO supplemented diet with SK challenge, while replacement of inorganic zinc (ZnO) by 100 or 50mg ZnONPs/kg diet reduced the adverse effect.

83. Impact of a Urine Culture Best Practice Advisory on Collection of Urine Cultures and Subsequent Antibiotic Therapy

BackgroundIn the acute care setting, urinary tract infections (UTIs) may be over diagnosed in up to 40% of cases. In most scenarios, asymptomatic bacteriuria (ASB) is not an indication for antibiotic therapy; inappropriate therapy is associated with a higher incidence of antibiotic-resistant bacteria and adverse drug reactions. Limiting inappropriate collection of urine cultures may decrease unnecessary treatment of ASB. The objective of this study is to assess the impact of a urine culture best practice advisory (BPA) on collection of unnecessary urine cultures. MethodsThis retrospective, observational, single-center study included adult inpatients with an order for urinalysis/urine culture. Those who were pregnant, had a concomitant infection other than UTI and/or were taking antimicrobials for a non-UTI indication, and were undergoing urological procedures were excluded. Duplicate urine culture collections and/or admissions were excluded. Incorporation of a BPA into computerized provider order entry, allowing providers to assess need and document indication for urine culture collection, was implemented on July 2019. The following clinical outcomes were assessed: number of unnecessary urine cultures collected, number of antibiotic treatments, and antibiotic-associated adverse reactions. ResultsTwo hundred met criteria for inclusion; 96 in the pre-BPA group (Aug – Oct 2018) and 104 in the post-BPA group (Aug – Oct 2019). Seventy-four (37%) were male and the mean age was 64 and 70 years (p=0.249), respectively. The Charlson Comorbidity Index (CCI) was similar between groups (4 vs. 5, p=0.162) and majority were admitted to a general medical ward (94.5%). Seventy patients (72.9%) in the pre-BPA group and 47 (51.6%) in the post-BPA group had inappropriately ordered urinalysis/urine cultures (OR 0.40; 95% CI 0.22-0.73; p=0.003). Of these patients, 15 (21.4%) and 9 (19.1%) from the pre- and post-BPA groups, respectively, were treated (p=0.077). Among those treated, only two adverse drug reactions were reported. ConclusionImplementation of a BPA significantly reduced the number of inappropriate urinalysis/urine culture orders. There was a trend towards decreased antibiotic use for ASB. Future studies are warranted to assess sustainability of these results. Disclosures All Authors: No reported disclosures

Development of a Novel Chimeric Endolysin, Lys109 With Enhanced Lytic Activity Against Staphylococcus aureus.

As the incidence of antibiotic-resistant bacteria has become increased, phage endolysins are believed as one of the promising alternatives to antibiotics. However, the discovery of potent endolysin is still challenging because it is labor intensive and difficult to obtain a soluble form with high lytic activity. In this respect, the modular structures of Gram-positive endolysins can provide an opportunity to develop novel endolysins by domain rearrangement. In this study, a random domain swapping library of four different endolysins from phages infecting Staphylococcus aureus was constructed and screened to obtain engineered endolysins. The novel chimeric endolysin, Lys109 was selected and characterized for its staphylolytic activity. Lys109 exhibited greater bacterial cell lytic activity than its parental endolysins against staphylococcal planktonic cells and biofilms, showing highly improved activity in eliminating S. aureus from milk and on the surface of stainless steel. These results demonstrate that a novel chimeric endolysin with higher activity and solubility can be developed by random domain swapping and that this chimeric endolysin has a great potential as an antimicrobial agent.

A Preliminary Study: Antibiotic Resistance of Escherichia coli and Staphylococcus aureus from the Meat and Feces of Various South African Wildlife Species.

This study determined the antibiotic resistance patterns of Escherichia coli and Staphylococcus aureus from the raw meat and feces of three game species from three different farms across South Africa. The Kirby-Bauer disk diffusion method was used according to the Clinical and Laboratory Standards Institute 2018 guidelines. E. coli was tested against ampicillin, ceftazidime, chloramphenicol, streptomycin, sulphafurazole and tetracycline. S. aureus was tested against tetracycline, erthromycin, vancomycin, penicillin, oxacillin and cefoxitin. There were no significant differences in the E. coli antibiotic resistance profiles between the meat and fecal samples (except towards ceftazidime where 5% of the meat isolates were resistant and 0% of the fecal isolates). The S. aureus meat isolates showed high (75%) resistance towards penicillin and on average, 13% were resistant to oxacillin/ cefoxitin, indicating methicillin resistance. The results from this study indicate that there is incidence of antibiotic resistant bacteria from the feces and meat of wildlife species across South Africa, suggesting that cross contamination of the meat occurred during slaughter by antibiotic resistant bacteria from the abattoir personnel or equipment and or from carcass fecal matter. In addition, the results highlight the importance of food safety and hygiene procedures during slaughter to prevent cross-contamination of antibiotic resistant bacteria, as well as pathogens, onto raw meat.

Correction:Low incidence of antibiotic-resistant bacteria in south-east Sweden: An epidemiologic study on 9268 cases of bloodstream infection.

[This corrects the article DOI: 10.1371/journal.pone.0230501.].

Nanocrystals of Fusidic Acid for Dual Enhancement of Dermal Delivery and Antibacterial Activity: In Vitro, Ex Vivo and In Vivo Evaluation.

With the alarming rise in incidence of antibiotic-resistant bacteria and the scarcity of newly developed antibiotics, it is imperative that we design more effective formulations for already marketed antimicrobial agents. Fusidic acid (FA), one of the most widely used antibiotics in the topical treatment of several skin and eye infections, suffers from poor water-solubility, sub-optimal therapeutic efficacy, and a significant rise in FA-resistant Staphylococcus aureus (FRSA). In this work, the physico-chemical characteristics of FA were modified by nanocrystallization and lyophilization to improve its therapeutic efficacy through the dermal route. FA-nanocrystals (NC) were prepared using a modified nanoprecipitation technique and the influence of several formulation/process variables on the prepared FA-NC characteristics were optimized using full factorial statistical design. The optimized FA-NC formulation was evaluated before and after lyophilization by several in-vitro, ex-vivo, and microbiological tests. Furthermore, the lyophilized FA-NC formulation was incorporated into a cream product and its topical antibacterial efficacy was assessed in vivo using a rat excision wound infection model. Surface morphology of optimized FA-NC showed spherical particles with a mean particle size of 115 nm, span value of 1.6 and zeta potential of −11.6 mV. Differential scanning calorimetry and powder X-ray diffractometry confirmed the crystallinity of FA following nanocrystallization and lyophilization. In-vitro results showed a 10-fold increase in the saturation solubility of FA-NC while ex-vivo skin permeation studies showed a 2-fold increase in FA dermal deposition from FA-NC compared to coarse FA. Microbiological studies revealed a 4-fofd decrease in the MIC against S. aureus and S. epidermidis from FA-NC cream compared to commercial Fucidin cream. In-vivo results showed that FA-NC cream improved FA distribution and enhanced bacterial exposure in the infected wound, resulting in increased therapeutic efficacy when compared to coarse FA marketed as Fucidin cream.

Self-assembly of glycerol monooleate with the antimicrobial peptide LL-37: a molecular dynamics study.

Over the past decade, the rapid increase in the incidence of antibiotic-resistant bacteria has promoted research towards alternative therapeutics such as antimicrobial peptides (AMPs), but their biodegradability limits their application. Encapsulation into nanocarriers based on the self-assembly of surfactant-like lipids is emerging as a promising strategy for the improvement of AMPs' stability and their protection against degradation when in biological media. An in-depth understanding of the interactions between the structure-forming lipids and AMPs is required for the design of nanocarriers. This in silico study, demonstrates the self-assembly of the amphiphilic lipid glycerol monooleate (GMO) with the antimicrobial peptide LL-37 into nanocarriers on the molecular scale. Molecular dynamics (MD) simulations show the formation of direct micelles, with either one or two interacting LL-37, and vesicles in this two-component system in agreement with experimental results from small-angle X-ray scattering studies. The hydrophobic contacts between LL-37 and GMOs in water appear responsible for the formation of these nanoparticles. The results also suggest that the enhanced antimicrobial efficiency of LL-37 in these nanocarriers that was previously observed experimentally can be explained by the availability of its side chains with charged amino acids, an increase of the electrostatic interaction and a decrease of the peptide's conformational entropy upon interacting with GMO. The results of this study contribute to the fundamental understanding of lipid–AMP interactions and may guide the comprehensive design of lipid-based self-assembled nanocarriers for antimicrobial peptides.

Clinical aspects of severe infections caused by antibiotic-resistant Gram-negative bacteria. The Empire strikes back?

In our days, growing incidence of antibiotic resistant bacteria has become an eminent public health problem. For survival Gram-negative species possess several different tools to withstand antibiotics: they produce degrading and modifying enzymes, decrease their permeability or expel drug molecules. An increasing proportion of severe nosocomial infections are caused by strains resistant to several antimicrobials (multiresistant, extensively resistant or panresistant species). Development of new antibiotic compounds may serve as a possible solution to this problem. Ceftolozane-tazobactam is a new beta-lactam+beta-lactamase-inhibitor combination resistant to most extended spectrum beta-lactamase enzymes showing excellent anti-Pseudomonas activity. It is also effective against strains when beta-lactam resistance is related to porin loss or efflux pump activity. The spectrum of ceftazidime-avibactam also includes carbapenemase-(KPC)-producing Enterobacteriaceae. In addition to novel therapy, an effective infection control system together with the prudent use of antimicrobials (antimicrobial stewardship) is of paramount importance. Orv Hetil. 2017; 158(39): 1528-1534.

Physico-chemical and bacteriological screening of Hussain Sagar lake: An urban wetland

Hussain Sagar is a man-made lake originally designed for drinking water purpose that receives domestic sewage and industrial effluents through drainage canals due to rapid residential and industrial growth. Also, every year thousands of idols are immersed into the lake during festivals. In this context, a comprehensive study was initiated for monitoring the lake water quality. Various physico-chemical parameters such as temperature, pH, EC, TDS, COD and chlorophyll a were analyzed using APHA standard methods Water was also monitored for heterotrophic bacteria, total coliforms, Escherichia coli and antibiotic resistant bacteria. The average values for heterotrophs were found to be 8.6 × 104 and 2.8 × 104 CFU/mL before and after idol immersion, respectively. While the average values for total coliforms and E. coli were 5 × 104 and 5 × 102; 1.2 × 104 and 7.2 × 101 CFU/mL, for the respective sampling periods. The mean values for ampicillin and gentamicin resistant bacteria were 5.9 × 103 and 6.9 × 102; and 2.2 × 103 and 5.4 × 102 CFU/mL, respectively. It was found that TDS, COD and chlorophyll a values were decreased after idol immersion due to extensive cleaning. The statistical results showed no correlation between faecal bacteria and physico-chemical parameters and one way-ANOVA indicated statistically significant differences between the mean values of different sampling locations, with respect to COD and E. coli at 95% confidence. However, enormous load of coliforms and E. coli indicated severe contamination of the lake with domestic sewage and human excreta. Thus, the water is not suitable for human consumption/drinking purpose. Notably, incidence of antibiotic resistant bacteria in lake water is a potential threat to both public health and the environment. Thus, regular monitoring and applying appropriate corrective actions are needed to improve the water quality.

Multi-antibiotic resistant extended-spectrum beta-lactamase producing bacteria pose a challenge to the effective treatment of wound and skin infections.

IntroductionThe increasing incidence of antibiotic resistant bacteria is a concern both to the clinicians and the patients due to obvious consequences such as treatment failures, prolonged patients’ stay in hospital and nosocomial infections. The choice of the first antibiotic therapy in emergency wards in hospitals is usually not based on patient-specific microbial culture and susceptibility test result.This study is aimed at profiling extended-spectrum beta-lactamase (ESBL) producing bacteria associated with wound injuries and highlighting their multi-antibiotic resistance character.MethodsSixty-three wound swab samples were collected and cultured on nutrient agar and on selective media. Evaluation for ESBL production was by phenotypic method while the antibiogram screening was by disc-diffusion.ResultsThe wounds evaluated were diabetic sore (14), cancer wounds (12), surgical wounds (17), wounds due to road traffic accidents (10) and wounds from fire burn (10). The result showed that 61 wounds were infected and the prevalence of the infecting pathogens was Escherichia coli 17.46%, Klebsiella Pneumonia 14.28%, Salmonella typhi 12.79%, Pseudomonas Aeruginosa 34.92% and Staphylococcus aureus 17.46%. Thirty four (55.74 %) isolates were ESBL producers, greater than 50% of which being Pseudomonas Aeruginosa. The antibiogram study of the ESBL producers showed multi-drug resistance with resistance highest against ampicillin (100%), followed by cephalosporins: cefuroxime (94.12%) and ceftriaxone (61.76%). No resistance was recorded against the β-lactamase inhibitors: amoxicillin/clavulanate and ceftriaxone/sulbactam. There was a high incidence (55.74 %) of ESBL-producing microbes in the wounds. The isolates were mostly multi-antibiotic resistant.ConclusionMulti-drug resistant ESBL-producing bacteria are common in wound infections in the community. However, amoxicillin/clavulanate or ceftriaxone/sulbactam may be used to treat most patients with such infections in the hospital. This may guide antibiotic selection and use in trauma, most especially in resource limited countries where laboratory test is unaffordable for a majority of patients.

Survival of antibacterial resistance microbes in hospital-generated recycled wastewater.

Hospital wastewater has the potential to be a threat to the hospital environment as it can contain pathogenic bacteria that may facilitate the resistant nature of organisms within effluent or water treatment plants. The recycling of hospital wastewater should have good quality. This study was carried out to highlight the incidence of antibiotic resistant bacteria in hospital-generated recycled water. This study was conducted in a tertiary care teaching hospital during June 2013-June 2014. One hundred and forty wastewater samples were aseptically collected at different stages in the recycling plant. The samples were processed within 2 hours following standard procedures for identification of bacteria and the pathogenic bacteria were isolated. The mostly identified pathogens were Staphylococcus aureus (11.42%), Pseudomonas aeruginosa (9.28%), Enterococcus faecalis (10%) and Bacillus subtilis (8.57%) which were removed by treatment, but Escherichia coli (16.42%), Klebsiella pneumonia (8.57%), and Proteus mirabilis (11.42%) survived in the final sedimentation tank (lagoon) from where this water will be used for gardening purposes. An antibiogram study showed these pathogens were resistant to first-line antibiotics. Effluent treatment plants in hospitals should be monitored for the fulfillment of the guidelines and quality control of treated water to stop the emergence of multi-drug resistant bacteria in the hospital environment.

IgG-dependent aggregation of Staphylococcus aureus inhibits bacteriophage attack

Staphylococcus aureus causes a variety of diseases, including bovine mastitis. The standard treatment regimen is treating it with antibiotics. However this approach has drawbacks, including high cost and the incidence of antibiotic-resistant bacteria. As a result, there has been renewed interest in the use of bacteriophages (phages) to control S. aureus. However, aggregation facilitates this bacterium’s persistence in the host, and the ability to aggregate has been increasingly recognized as an important Staphylococcus virulence factor. This study revealed that polyclonal bovine IgG enhanced aggregation of S. aureus (SA003), isolated from raw-milk samples from cows with mastitis. IgG-dependent aggregation delayed lysis of SA003 by the specific bacteriophage (ΦSA012), originally isolated from sewage influent. Addition of IgG also lowered the phage–host adsorption rate constant (ka). The ka value of the IgG-containing condition was approximately 1/8 of that of the IgG-free condition. In addition to the decrease of ka value, increase of the minimum inhibitory concentration (MIC) of ΦSA012 toward SA003 was observed. Fluorescence microscopical and confocal laser microscopical observations revealed that phages were mainly localized on the surfaces of cell aggregates. IgG-dependent S. aureus aggregation in crude milk is a problem that must be solved before phage therapy can be successfully used to treat bovine mastitis caused by this bacterium.

Biotic Relationships: Distribution of Antibiotic Resistance Genes in Nosocomial Pathogens

The strong selective pressure exerted by excessive use of antibiotics in the last decades has increased the acquisition of resistance genes by horizontal gene transfer. Horizontal gene transfer contributed to the diversification of microorganisms by influencing traits such as metabolic potential of a bacterial cell, antibiotic resistance, symbiosis, fitness, and adaptation. The study of biotic relationships helped to examine how they may contribute to virulence such as transfer of toxin genes, antibiotic resistance genes. The current study examines the pattern of distribution of Ambler (molecular) classes of β-lactamases (A, B, C, D) that provides a basic understanding and an initial assessment of resistance genes that may have a different role in the natural environment in free living and symbiotic nosocomial pathogens. The distribution of the four different Ambler (molecular) classes of β-lactamases (A, B, C, and D) differs among different bacterial species. The results from absolute abundance data showed prevalence of class B β-lactamases was highest in free living and lowest in symbiotic bacterial species. Interestingly, class D β-lactamases was absent in symbiotic bacterial species. However, relative abundance class D β-lactamases was lowest for free-living bacterial species. The prevalence of class B β-lactamases based upon the total number of sequences checked predominated in pathogens that are free living when compared to other Ambler classes of β-lactamases. The study of biotic relationships helps to understand what selective or stimulatory pressures are driving the spread of antibiotic resistance genes. In the future, this may help to design effective strategies for preventing further increases in the incidence of antibiotic-resistant bacteria.

Effect of Chitosan onSalmonellaTyphimurium in Broiler Chickens

Public concern with the incidence of antibiotic-resistant bacteria, particularly among foodborne pathogens such as Salmonella, has been challenging the poultry industry to find alternative means of control. The purposes of the present study were to evaluate in vitro and in vivo effects of chitosan on Salmonella enterica serovar Typhimurium (ST) infection in broiler chicks. For in vitro crop assay experiments, tubes containing feed, water, and ST were treated with either saline as a control or 0.2% chitosan. The entire assay was repeated in three trials. In two independent in vivo trials, 40 broiler chicks were assigned to an untreated control diet or dietary treatment with 0.2% chitosan for 7 days (20 broiler chicks/treatment). At day 4, chicks were challenged with 2×10⁵ colony-forming units (CFU) ST/bird. In a third in vivo trial, 100 broiler chicks were assigned to untreated control diet or dietary treatment with 0.2% chitosan for 10 days (50 broiler chicks/treatment) to evaluate ST horizontal transmission. At day 3, 10 birds were challenged with 10⁵ CFU ST/bird, and the remaining nonchallenged birds (n=40) were kept in the same floor pen. In all three in vitro trials, 0.2% chitosan significantly reduced total CFU of ST at 0.5 and 6 h postinoculation compared with control (p<0.05). In two in vivo trials, at 7 days, dietary 0.2% chitosan significantly reduced total CFU of recovered ST in the ceca in both experiments. Dietary 0.2% chitosan significantly reduced total ST CFU recovered in the ceca of horizontally challenged birds in the third in vivo trial. Chitosan at 0.2% significantly reduced the CFU of recovered ST in vitro and in vivo, proving to be an alternative tool to reduce crop, ceca, and consequently carcass ST contamination as well as decreasing the amount of ST shed to the environment.

P122: Hand hygiene in Swedish health care – past and present work

Hand hygiene (HH) is widely recognized as one of the most effective preventive measures against health care associated infections (HCAI). Alcoholic hand rub (AHR) has been used as standard HH method in Swedish HC for more than three decades. Infection control (IC) experts in Sweden regards this as one among several explanations for the low incidence of antibiotic resistant bacteria, e.g. MRSA (methicillin resistant Staphylococcus aureus), in Swedish HC.

Screening of antibiotic resistant gram negative bacteria and Plasmid profiling of multi-drug resistant isolates present in sewage associated with health care centers

Background: Healthcare effluent acts as the store house of harmful infectious agents such as the pathogens and microorganisms possessing multiple drug resistant genes. Potential health risk includes spreading of diseases by these pathogens and wide dissemination of antimicrobial resistance genes. Gram-negative bacteria are particular ly important for causing most of the hospital and community acquired infections. Aim: This study was carried out to highlight the incidence of antibiotic resistant bacteria in hospital generated effluent discharged into municipal sewage system of Sylhet city, Bangladesh. Methodology: Standard biochemical tests were used to isolate and identify 29 gram negative bacteria from 6 effluent samples . Antibiotic susceptibility test was assessed by Kirby-Bauer disc diffusion method. Plasmid isolation and gel electrophoresis were performed using standard protocols. Results: Antibiogram study showed that the percentage of isolates resistant to amoxicillin, ceftriaxone, ciprofloxacin, gentamicin, imipenem, azithromycin, andsulphamethoxazole-trimethoprim were 93.10%, 55.17%, 27.6%, 24.14%, 20.7%, 13.8% and 10.34% respectively. Ten of the isolates showed resistance to three or more commonly used antibiotics. Plasmid profiles of the multi-drug resistant isolates showed to harbor two or more plasmids and almost all of them showed a common band for plasmid DNA size of 24.5kb. Conclusion: Resistance to the bacterial pathogens causing community acquired infections may, thus, exert a serious public health threat through confining the antibiotic pool. Hospitals should follow, monitor and regulate proper sanitary measures of hospital generated effluents to forestall the dissemination of multi drug resistant bacteria transfer from hospital waste to the environment.

Contaminants and microorganisms in Dutch organic food products: a comparison with conventional products

Organic products were analysed for the presence of contaminants, microorganisms and antibiotic resistance and compared with those from conventional products. No differences were observed in the Fusarium toxins deoxynivalenol and zearalenone in organic and conventional wheat, during both a dry period and a very wet period which promoted the production of these toxins. Nitrate levels in head lettuce produced organically in the open field were much lower than those in conventional products. In iceberg lettuce and head lettuce from the greenhouse, no differences were detected. Organically produced carrots contained higher nitrate levels than conventional products. Both organic and conventional products contained no residues of non-polar pesticides above the legal limits, although some were detected in conventional lettuce. Organic products contained no elevated levels of heavy metals. Salmonella was detected in 30% of pig faeces samples obtained from 30 organic farms, similar to the incidence at conventional farms. At farms that switched to organic production more then 6 years ago no Salmonella was detected, with the exception of one stable with young pigs recently purchased from another farm. No Salmonella was detected in faeces at the nine farms with organic broilers, and at one out of ten farms with laying hens. This is comparable with conventional farms where the incidence for Salmonella lies around 10%. Campylobacter was detected in faeces at all organic broiler farms, being much higher than at conventional farms. One of the most remarkable results was the fact that faeces from organic pigs and broilers showed a much lower incidence of antibiotic resistant bacteria, except for Campylobacter in broilers. It is concluded that the organic products investigated scored as equally well as conventional products with regard to food safety and at the same time show some promising features with respect to antibiotic resistance.