Proportion Of Antibiotic-resistant Bacteria Research Articles

Hygiene of Medical Devices and Minimum Inhibitory Concentrations for Alcohol-Based and QAC Disinfectants among Isolates from Physical Therapy Departments.

Disinfectants are used intensively to control and prevent healthcare-associated infections. With continuous use and exposure to disinfectants, bacteria may develop reduced susceptibility. The study aimed to check the hygiene of devices in the physiotherapy department. For isolated bacterial strains, we aimed to determine the minimum inhibitory concentration of five different disinfectant wipe products currently in use. Microbiological environmental sampling in four various institutions in four different cities from two counties was performed, followed by CFU calculation and identification using matrix-assisted laser desorption and ionization with time-of-flight analyzer mass spectrometry (MALDI-TOF). The sampling was performed on three different occasions: before patient use, after patient use, and after disinfection. The susceptibility of isolates to three different alcohol-based and three different quaternary ammonium compounds (QAC) disinfectant wipes was examined by determining the minimal inhibitory concentrations (MIC). We identified 27 different bacterial species from 11 different genera. Gram-positive bacteria predominated. The most abundant genera were Staphylococcus, Micrococcus, and Bacillus. The average MIC values of alcohol-based disinfectants range between 66.61 and 148.82 g/L, and those of QAC-based disinfectants range between 2.4 and 3.5 mg/L. Distinctive strains with four-fold increases in MIC values, compared to average values, were identified. The widespread use of disinfectants can induce a reduction in the susceptibility of bacteria against disinfectants and affect the increase in the proportion of antibiotic-resistant bacteria. Therefore, it is urgent to define clear criteria for defining a microorganism as resistant to disinfectants by setting epidemiological cut-off (ECOFF) values and standardizing protocols for testing the resistance of microorganisms against disinfectants.

Modern technologies for storing semen of domestic animals without the addi-tion of antibiotics

Currently, there is a trend of breeding domestic animals through artificial insemination. As a result, very large amounts of sperm diluents containing antibiotics are used in animal husbandry. Antimicrobials are added to the semen diluent to control the growth of bacteria that contaminate the semen during selection. The proportion of antibiotic-resistant bacteria is steadily rising, threatening the entire health care system. That is why all fields of antibiotics application face the task of finding alternatives to this approach. The purpose of our study was to systematize modern technologies and methods of storing domestic animals’ semen which could reduce or eliminate the use of antibiotics, and would be an important step in the fight against multidrug-resistant bacteria. Due to the negative impact of antibiotics on sperm quality and their fertilizing ability, new alternative methods for sperm storage are constantly being improved and developed. The most common are low-temperature storage, physical methods to reduce bacterial stress, the use of antimicrobial peptides, nanoparticles and the use of various substances of animal, plant or other origin. The possibility of boar sperm low-temperature storage may open up completely new approaches in the future by optimizing the cooling rate. Colloidal centrifugation as one of the physical methods is a practical means of reducing the bacterial load in sperm samples and it can be effectively used applying equipment that is available at many breeding plants. Antimicrobial peptides or nanoparticles of iron oxide may be a useful alternative to the addition of antibiotics during sperm storage. Antimicrobial peptides have been shown to control the growth of aerobic and anaerobic bacteria in relatively low concentrations without adversely affecting sperm quality and fertility. However, it is substantiated that nanoparticles with the size of 40 – 60 nm have significant antimicrobial ability against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. At the same time, further studies are needed on the use of various substances of animal or plant origin (royal jelly, aloe vera, algae extracts), as well as determining adequate concentrations of these new compounds that should be effective in fighting bacteria and not affect quality characteristics of sperm.

Antimicrobial resistance in wastewater of Yangon Region, Myanmar from one health perspective

Background: Antibiotic resistance is an emerging concern both for public and animal health globally and also threatens the achievements of modern medicine. This study aimed to generate the baseline data of drug resistance pathogens in diversity of waste water of Yangon Region, Myanmar.Methods: A cross-sectional descriptive study was conducted from January to July 2021. A total of forty samples of wastewater (two samples each from ten hospitals, one sample each from five poultry farms, five aquacultures and ten community drains) were aseptically collected, transported in ice box and processed following standard procedure for bacterial isolation and detection of antibiotic sensitivity pattern. Identification and antibiotic susceptibility testing of isolated colonies were done by VITEK 2 compact system.Results: A total of 106 bacterial isolates were identified and 50% were from hospitals, 31.1%were from community drains and 9.4% each from poultry farms and aquacultures. The most frequently identified isolates were Enterobacteriaceae (65.1%) followed by Acinetobacter species (11.3%) and Pseudomonas species (8.5%). Among the isolated organisms, ESBL producers and Carbapenemase producer were 7.5% and 0.9% respectively. ESBL producers (62.5%) were resistant to cefuroxime, cefuroxime-axetil, cefotaxime, ceftriaxone and minocycline. Carbapenem resistant Enterobacteriaceae was multidrug resistant but sensitive to amikacin, tigecycline and cefaclor.Conclusions: The proportion of antibiotic resistant bacteria are higher in hospital wastewater than other sites. Hence proper treatment plant for hospital wastewater should be installed and need to mitigate antibiotic resistance with a ‘one-health’ approach.

Prevalence of antimicrobial resistance among gram-negative clinical isolates from a general hospital in Kuwait

Background: The impact of antimicrobial resistance on public health is a major issue worldwide. The objective of this study was to determine the antimicrobial resistance patterns of clinical gram-negative bacterial (GNB) isolates originated from different samples and locations at a general hospital in Kuwait. Methods and materials: A retrospective data of antimicrobial susceptibility testing of GNB from 2017–2018 were extracted from the microbiology laboratory at a general hospital in Kuwait. The data included the patient ID, location where the samples were collected (ICU, medical, pediatric, surgical, and out-patient clinics), specimen type, bacterial isolates (Acinetobacter spp., Enterobacter spp., E. coli, K. Pneumoniae, and P. aeruginosa), and the antimicrobial resistance profile. The susceptibility testing was performed using Vitek 2 and MicroScan systems. Results: Antimicrobial resistance profiles from a total of 6135 GNB isolates were obtained. In general, high resistance percentages (>50%) towards ampicillin, aztreonam, ciprofloxacin, trimethoprim/sulfamethoxazole, and cephalosporins drugs (ceftazidime, cefpodoxime, cefotaxime, and cefuroxime) was observed across the different bacterial species. However, low resistance (<10%) was generally observed against amikacin, amoxicillin/clavulanic acid, ertapenem, fosfomycin, nitrofurantoin, meropenem, piperacillin/tazobactam, and tigecycline. The proportion of antibiotic resistant bacteria by locations varied greatly by the microorganism isolated. For instance, E. coli isolates from medical and surgical wards had higher resistance prevalence compared to the other locations; whereas P. aeruginosa isolates from pediatric ward had higher resistance prevalence to antibiotics compared to other locations. The highest overall resistance (across all bacterial isolates) was detected in urine and wound samples. For instance, in urine samples, 22% and 26.3% of E. coli and K. Pneumoniae were resistant to amoxicillin/clavulanic acid. The prevalence of resistance to at least one antibiotic was high particularly among E. coli, K. Pneumoniae, and P. aeruginosa at 78.2%, 91.0%, and 73.6%, respectively. Moreover, the prevalence of multi-drug resistance among E. coli, K. Pneumoniae, and P. aeruginosa was 50.3%, 51.3%, and 48.7%, respectively. Conclusion: Monitoring the antibiotic susceptibility data of common bacterial organisms is vital to assess the status and trends of antibiotic resistance at hospital setting, to evaluate effective intervention strategies, and to select appropriate antibiotic treatment.

Antibiotic-manufacturing sites are hot-spots for the release and spread of antibiotic resistance genes and mobile genetic elements in receiving aquatic environments

High antibiotic releases from manufacturing facilities have been identified as a risk factor for antibiotic resistance development in bacterial pathogens. However, the role of antibiotic pollution in selection and transferability of antibiotic resistance genes (ARGs) is still limited. In this study, we analyzed effluents from azithromycin-synthesis and veterinary-drug formulation facilities as well as sediments from receiving river and creek taken at the effluent discharge sites, upstream and downstream of discharge. Culturing showed that the effluent discharge significantly increased the proportion of antibiotic resistant bacteria in exposed sediments compared to the upstream ones. Quantitative real-time PCR revealed that effluents from both industries contained high and similar relative abundances of resistance genes [sul1, sul2, qacE/qacEΔ1, tet(A)], class 1 integrons (intI1) and IncP-1 plasmids (korB). Consequently, these genes significantly increased in relative abundances in receiving sediments, with more pronounced effects being observed for river than for creek sediments due to lower background levels of the investigated genes in the river. In addition, effluent discharge considerably increased transfer frequencies of captured ARGs from exposed sediments into Escherichia coli CV601 recipient as shown by biparental mating experiments. Most plasmids exogenously captured from effluent and polluted sediments belonged to the broad host range IncP-1ε plasmid group, conferred multiple antibiotic resistance and harbored class 1 integrons. Discharge of pharmaceutical waste from antibiotic manufacturing sites thus poses a risk for development and dissemination of multi-resistant bacteria, including pathogens.

Spatial and temporal variation of antibiotic resistance in marine fish cage-culture area of Guangdong, China

The rapid emergence and dissemination of antibiotic resistance poses a threat to human health and to the marine environment. We have investigated the abundance and diversity of antibiotic resistance genes (ARGs) and of antibiotic-resistant bacteria (ARB), during the seedling period, rearing period, and harvesting period in seven marine fish cage-culture areas in Guangdong. Spatial and temporal variations of AGRs and ARB were also analyzed. Culture-based methods and quantitative PCR were used to detect ARB and ARGs. Bacterial resistance rates were no significantly different within farming periods. The proportion of antibiotic-resistant bacteria was extremely low (average on 1.15%), except for oxytetracycline-resistant bacteria (average on 34.15%). Vibrio was the most common ARB. Sul1, tetB, and ermB, had the highest relative abundance. The abundance of ARGs in the harvesting period was significant highest. The total abundance of ARGs was highest at Raoping and lowest at Dayawan and Liusha. Most ARGs were associated with opportunistic pathogens. The environmental factors effecting ARB and ARGs are complex, and no key factors were identified. This study provides a theoretical basis for assessing the harmfulness of ARGs and ARB to food safety and human health.

Increase in Antibiotic-Resistant Gram-Negative Bacterial Infections in Febrile Neutropenic Children.

BackgroundThe incidence of bacteremia caused by Gram-negative bacteria has increased recently in febrile neutropenic patients with the increase of antibiotic-resistant Gram-negative bacterial infections. This study aimed to identify the distribution of causative bacteria and the proportion of antibiotic-resistant bacteria in bacteremia diagnosed in febrile neutropenic children.Materials and MethodsThe medical records of febrile neutropenic children diagnosed with bacteremia between 2010 and 2014 were retrospectively reviewed. The causative bacteria and proportion of antibiotic-resistant bacteria were investigated and compared yearly during the study period. The clinical impact of antibiotic-resistant bacterial infections was also determined.ResultsA total of 336 bacteremia episodes were identified. During the entire study period, 181 (53.9%) and 155 (46.1%) episodes were caused by Gram-negative and Gram-positive bacteria, respectively. Viridans streptococci (25.9%), Klebsiella spp. (16.7%), and Escherichia coli (16.4%) were the most frequent causative bacteria. The overall distribution of causative bacteria was not significantly different annually. Antibiotic-resistant bacteria were identified in 85 (25.3%) episodes, and the proportion of antibiotic-resistant bacteria was not significantly different annually. Extended-spectrum β-lactamase-producing E. coli and Klebsiella spp. were most common among antibiotic-resistant Gram-negative bacteria, and they accounted for 30.6% (n = 34) of the identified E. coli and K. pneumoniae. Methicillin-resistant coagulase-negative staphylococci were most common among antibiotic-resistant Gram-positive bacteria, and it accounted for 88.5% (n = 23) of the identified coagulase-negative staphylococci. Antibiotic-resistant bacterial infections, especially antibiotic-resistant Gram-negative bacterial infections, caused significantly higher mortality due to bacteremia compared with non-antibiotic-resistant bacterial infections (P <0.001).ConclusionRecently, Gram-negative bacteria caused more bacteremia cases than Gram-positive bacteria in febrile neutropenic children, and antibiotic-resistant Gram-negative bacterial infections increased. Antibiotic-resistant bacterial infections caused poorer prognosis compared with non-antibiotic-resistant bacterial infections, and therefore, continuous surveillance for changing epidemiology of antibiotic-resistant bacterial infections and their clinical impact is necessary.

Superbugs: the ever growing threat in our food supply

Dear Editor, Antibiotic resistance is rapidly rising. Many bacterial infections are now very difficult, and sometimes impossible, to treat. Gram negative bacteria are the pointy end of this growing problem, including very common bacteria such as E. coli. Antibiotic resistance is proportional to use. The more antibiotics used, the more resistance develops and spreads. This is both in individuals (e.g. with pneumococcus) and for populations in different countries. With many common bacteria, transmission is almost entirely human-to-human (e.g. pneumococcus, gonococcus, meningococcus). Thus, any antibiotic resistance seen in these bacteria will be almost entirely due to antibiotics used in the human sector. However with some other bacteria, the resistance seen is almost entirely due to what has occurred in the agriculture sector. Examples are non-typhoid salmonella and campylobacter. In developed countries these bacteria are almost entirely acquired from food animals (via foods). These are zoonoses, and thus almost all the antibiotic resistance is a result of what happens with antibiotic use in food animals. Vegetarians are also at risk because water, food crops and fields (via manure) can be contaminated with resistant bacteria. There is also the additional chance of cross contamination of non-meat products from meats along the food chain. There are other bacteria where the risk of acquisition from animal sources is more difficult to precisely define, but appears to be quite important. Examples are E. coli and Enterococcus. We also sometimes get surprises. Until recently Staphylococcus aureus and MRSA were thought to be almost fairly exclusive human pathogens. However, in many countries (e.g. The Netherlands and Denmark), MRSA is now found frequently in pigs and these strains infect people. Clostridium difficile is now clearly associated with food animals and people are infected with strains found in these animals. There are increasing numbers of people with community onsetC. difficile infections. Foods are a likelyway these bacterial strains were acquired. Resistant E. coli are a major concern because E. coli is the most commonbacterial pathogen causing serious infections in people. Bloodstream infection rates vary from 25–60 per 100 000 people per year.This is just the tip of the iceberg, for every such serious and life threatening bloodstream infection, there are likely to be about a hundred other infections (e.g. urinary tract infections).What is nowvery disconcerting is the increasingmulti-resistance resistanceworldwide inE. coli. Much of this resistance in E. coli (especially to third generation cephalosporins and fluoroquinolones) is related to resistance that develops in bacteria carried by food animals – especially poultry. This resistance results from the misuse of antibiotics in these animals. Worldwide each year, billions of chicken are injected with third generation cephalosporins just before or after hatching (with ceftiofur) and/or fed fluoroquinolones in their drinking water (e.g. enrofloxacin) for nearly all their lives. Antibiotics have been used for over 60 years as growth promoters. They are also used for prophylaxis (called ‘metaphylaxis’when large numbers of animals or entire herds are treated at the same time). This is in stark contrast to what happens in human medicine, where individual patient use is the norm. It effectively means that huge numbers of animals are treated continuously for most of their life with either in-feed or in-water antibiotics. It explains why over 70% of all antibiotics used in most countries are used in food animals. Some of these prophylactic antibiotics are last-line or ‘critically important’ classes of antibiotics for humans, such as the fluoroquinolones and third and fourth generation cephalosporins. While there is ongoing debate on what proportion of antibiotic resistant bacteria infecting people come from food animals, it appears to be substantial. An example of where good practice can help people with serious infections is Australia. It is the only country that has banned the use of fluoroquinolones in food animals. It is not coincidental that Australia has also one of the lowest resistance rates in campylobacter, salmonella and E. coli to fluoroquinolones in the world.

Effect of chlorination and ultraviolet disinfection on tetA-mediated tetracycline resistance of Escherichia coli

Antibiotic-resistant bacteria are an emerging threat to public health during drinking water consumption and reclaimed water reuse. Several studies have shown that the proportions of antibiotic-resistant bacteria in waters may increase when exposed to low doses of UV light or chlorine. In this study, inactivation of tetracycline-resistant Escherichia coli and antibiotic-sensitive E. coli by UV disinfection and chlorination was compared to determine the tolerance of tetracycline-resistant E. coli to UV light and chlorine, and tetracycline resistance of a tetracycline-resistant E. coli population was studied under different doses of the disinfectants. Our results showed that relative to antibiotic-sensitive E. coli, tetracycline-resistant E. coli had the same tolerance to UV light and a potentially higher tolerance to chlorination. The mortality frequency distributions of tetracycline-resistant E. coli exposed to tetracycline were shifted by both chlorination and UV disinfection. When compared to the hemi-inhibitory concentrations (IC50) of tetracycline-resistant E. coli with no exposure to UV or chlorination, the IC50 of tetracycline-resistant E. coli treated with tetracycline was 40% lower when inactivation by UV light or chlorination reached 3-log but was 1.18 times greater when inactivation by chlorination reached 4.3-log. Chlorination applied to drinking water or reclaimed water treatment may increase the risk of selection for highly tetracycline-resistant E. coli.

Fecal indicator bacteria resistance to antibiotics in experimental constructed wetlands

Antibiotic resistant bacteria (ARB) to amoxicillin, amoxicillin+clavulanic acid, azithromycin and doxycycline were tested in the effluent water of seven different pilot scale constructed wetlands (CW) and in an urban wastewater treatment plant (WWTP) treating the same influent. It was also analysed the ability of the CW to remove bacteria from the influent. CW differed from each other in flow type (free water surface flow, subsurface flow or hydroponics), plant species (Typha angustifolia, Phragmites australis or unplanted) and effluent position (upper part or bottom of the tank). Three groups of bacteria were tested, total Coliforms, Escherichia coli, and Enterococcus, and cultivated after membrane filtering in media with different antibiotic concentrations. No significant differences were found in the proportions of ARB among the CW, or between these and the WWTP. However, hydraulic design and plant presence were found to be extremely important in reducing total number of bacteria, which is related to the total number of resistant bacteria. Higher bacterial removal in CW (especially in those with subsuperficial flow) than in activated sludge means much lower ARB loadings to the environment by CW.

Resisting Arrest: Drug-Resistant Campylobacter Persists in Poultry

Vol. 115, No. 7 EnvironewsOpen AccessResisting Arrest: Drug-Resistant Campylobacter Persists in Poultry Angela Spivey Angela Spivey Search for more papers by this author Published:1 July 2007https://doi.org/10.1289/ehp.115-a362bAboutSectionsPDF ToolsDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InReddit Doctors use the fluoroquinolone class of antibiotics to treat food poisoning caused by Campylobacter. But after poultry farmers began using fluoroquinolones to treat respiratory disease in flocks, the drugs became less effective in people. In 2005, the FDA banned the use of fluoroquinolones on poultry farms because of these concerns. A new study now suggests that the ban may not be enough to fix the problem [EHP 115:1035–1039; Price et al.].A team of Johns Hopkins researchers made weekly trips to Baltimore supermarkets for 20 weeks in 2004 and 15 weeks in 2006. Each week, they bought chicken from each of five different producers. Three producers had never used any antibiotics; two were major conventional producers that declared they had ceased all use of fluoroquinolones in 2002, three years before the FDA ban. The scientists tested one piece of chicken from each package for Campylobacter, confirmed the bacterium’s identity using DNA analysis, then tested for antibiotic resistance using the minimal inhibitory concentration method.The bacteria from conventional chicken were more likely to be fluoroquinolone-resistant than those from antibiotic-free products. The researchers compared each poultry producer to every other producer in a pair-wise fashion. In both 2004 and 2006, this statistical analysis showed that the Campylobacter strains from the conventionally produced chicken were more likely to be resistant than the strains from antibiotic-free samples.In addition, between 2004 and 2006, the proportion of antibiotic-resistant bacteria on the conventionally produced chicken showed no significant change, indicating that the prevalence of fluoroquinolone-resistant Campylobacter was not decreasing in chicken from these producers, even after four years.The results suggest that once antibiotic-resistant bacteria have developed, they may show up on grocery store shelves long after drug use stops. The authors note that they could not verify claims of voluntary fluoroquinolone prohibition because poultry producers are not required to report their use of drugs in food animals to regulatory agencies.Other studies have shown that resistant bacteria can linger in poultry farms’ water distribution and ventilation systems and in reused litter. The authors state that additional interventions, such as requiring thorough disinfection and regular litter changing in poultry houses, may be necessary to reduce the public health burden of fluoroquinolone-resistant Campylobacter.FiguresReferencesRelatedDetails Vol. 115, No. 7 July 2007Metrics About Article Metrics Publication History Originally published1 July 2007Published in print1 July 2007 Financial disclosuresPDF download License information EHP is an open-access journal published with support from the National Institute of Environmental Health Sciences, National Institutes of Health. All content is public domain unless otherwise noted. Note to readers with disabilities EHP strives to ensure that all journal content is accessible to all readers. However, some figures and Supplemental Material published in EHP articles may not conform to 508 standards due to the complexity of the information being presented. If you need assistance accessing journal content, please contact [email protected]. Our staff will work with you to assess and meet your accessibility needs within 3 working days.