Occurrence Of Antibiotic-resistant Bacteria Research Articles

Occurrence of antibiotic-resistant bacteria in household greywater discharged into the environment in Burkina Faso's Sahel region

ABSTRACT The prevalence and antibiotic resistance of Salmonella spp. and Staphylococcus spp. from greywater were investigated in Africa's Sahel region, Burkina Faso. A total of 36 and 56 isolates of Salmonella spp. and Staphylococcus spp. were isolated from greywater, respectively. From the Salmonella spp. isolates, resistance was most frequently observed against vancomycin (69%), ampicillin (61%), cefoxitin (42%), trimethoprine/sulfamethoxazole (36%), amoxicillin-clavunal acid (33%) and tetracycline (33%). For all Staphylococcus spp. isolates, the highest rate of resistance was against penicillin (55.36%) followed by oxacillin (48.21%) and clindamycin (30.36%). In addition, 75% of the isolated Salmonella spp. strains were resistant to at least two antibiotics of different families, while 30.35% of Staphylococcus spp. strains were multidrug-resistant (MDR). Overall, this is one of the first studies reporting the presence of MDR bacteria in untreated greywater discharged from domestic activities in Burkina Faso. Our results show that untreated greywater can contain bacteria resistant to antibiotics used in therapeutic care. Therefore, uncontrolled discharge of untreated greywater into the environment could lead to the dissemination of resistant bacteria and resistance genes in the environment and increase the risk of human exposure to antimicrobial resistance.

Antibiotic Resistance in Enterococci and Enterobacteriaceae from Laboratory-Reared Fresh Mealworm Larvae (Tenebrio molitor L.) and Their Frass.

The occurrence of antibiotic-resistant bacteria in foodstuff involves a human health risk. Edible insects are a precious resource; however, their consumption raises food safety issues. In this study, the occurrence of antibiotic resistant bacteria in laboratory-reared fresh mealworm larvae (Tenebrio molitor L.) and frass was assessed. Antibiotics were not used during the rearing. Enterobacteriaceae and enterococci were isolated from 17 larvae and eight frass samples. In total, 62 and 69 isolates presumed to belong to Enterobacteriaceae and Enterococcus spp., respectively, were obtained and tested for antibiotic susceptibility via disk diffusion. Based on the results, isolates were grouped, and representative resistant isolates were identified at species level through 16S rRNA gene sequencing. For enterococci resistance, percentages higher than 15% were observed for vancomycin and quinupristin-dalfopristin, whereas Enterobacteriaceae resistance higher than 25% was found against cefoxitin, ampicillin, and amoxicillin-clavulanic acid. Based on the species identification, the observed resistances seemed to be intrinsic both for enterococci and Enterobacteriaceae, except for some β-lactams resistance in Shigella boydii (cefoxitin and aztreonam). These could be due to transferable genetic elements. This study suggests the need for further investigations to clarify the role of edible insects in the spreading of antibiotic resistance determinants through the food chain.

Occurrence of Antibiotic-Resistant Bacteria in Fish and Seafood from Slovak Market.

The consumption of sushi or poke has grown globally. However, this type of dish often contains raw fish or seafood; therefore, it can pose a microbial risk for consumers. This study deals with the occurrence of total and antibiotic-resistant coliform bacteria and enterococci in fish and seafood as well as sushi and poke bought from Slovak retail (restaurants and fast food). Total coliforms have ranged in sushi, poke samples and samples of fish and seafood from cooling counters from 0.6 to 5.1 log CFU/g. Ampicillin resistance has been predominantly observed in all types of samples. Tetracycline resistance was detected in 16% of all tested samples and gentamicin resistance in 13%. Total enterococci has been detected in 74% of sushi samples, 100% of poke samples and 62% of samples obtained from supermarkets. The majority of enterococci were resistant to ampicillin. Vancomycin resistance was observed in five samples. Forty-eight resistant coliforms were identified mainly as Enterobacter spp. and Klebsiella spp. Antibiotic-resistant isolates were predominantly resistant to gentamicin, chloramphenicol and tetracycline. In 13% of resistant isolates was detected efflux pumps overproduction, and in four isolates was detected the tetA resistance gene. Our results point to poor hygiene in some establishments. The prevention of the antibiotic-resistant bacteria spread would be in better stewardship and improved monitoring of sanitation.

Occurrence of Antibiotic-Resistant Bacteria and Their Genes in Bagmati River, Nepal

Occurrence of Antibiotic-Resistant Bacteria and Their Genes in Bagmati River, Nepal

Water Quality Analysis and The Occurrence of Antibiotic-Resistant Bacteria (ARB) From Satow Waterfall in Bau, Malaysian Borneo

Water quality monitoring of a particular river is crucially important to determine if the river water meets the requirement for its designated uses. Therefore, an assessment of the physiochemical water quality at Satow Waterfall, Sarawak, and the prevalence of antibiotic-resistant bacteria (ARB) was conducted to corroborate the safety of the water from the waterfall. A total of 42 water samples were collected at the subsurface water of the upstream, midstream, and downstream on two sampling trips in June 2021 (dry season) and December 2021 (wet season), with six months intervals. The water quality index (WQI) of the sampling stations ranged from 92.60 to 95, classifying the water under Class I. However, the water is microbiologically polluted, with the highest coliform count of 2.59 × 105 CFU/mL recorded at the middle stream during the wet season, which has surpassed the regulatory standard set by the Malaysian Department of Environment (DOE). A total of 54 bacterial isolates were chosen as representatives and identified by 16S rRNA sequencing, which confirmed the existence of 21 bacterial genera. All identified isolates were tested against 15 antibiotics of various classes employing the Clinical and Laboratory Standards Institute (CLSI) protocols. The antibiotic susceptibility test (AST) demonstrated substantial resistance to sulfamethoxazole (48%) and erythromycin (48%), as well as high susceptibility to chloramphenicol (84%), levofloxacin (60%) and ofloxacin (60%). The Multiple Antibiotic Resistance Index (MARI) evaluations demonstrated the MARI varied from 0-0.60, with 33% of the isolates having a MARI greater than 0.2. In this study, the occurrence of ARB in a water environment where there is an undisclosed source of antibiotic utilization is still inevitable, highlighting the necessity to constantly monitor the water quality and the pervasiveness of ARB in recreational water.

Low antimicrobial resistance in Escherichia coli isolates from two large Austrian alpine karstic spring catchments

The increasing occurrence of antibiotic resistant bacteria poses a threat to global public health. Clinically relevant resistances also spread through the environment. Aquatic ecosystems in particular represent important dispersal pathways. In the past, pristine water resources have not been a study focus, although ingestion of resistant bacteria through water consumption constitutes a potentially important transmission route. This study assessed antibiotic resistances in Escherichia coli populations in two large well-protected and well-managed Austrian karstic spring catchments representing essential groundwater resources for water supply. E. coli were detected seasonally only during the summer period. By screening a representative number of 551 E. coli isolates from 13 sites in two catchments, it could be shown that the prevalence of antibiotic resistance in this study area is low. 3.4 % of the isolates showed resistances to one or two antibiotic classes, 0.5 % were resistant to three antibiotic classes. No resistances to critical and last-line antibiotics were detected. By integrating fecal pollution assessment and microbial source tracking, we could infer that ruminants were the main hosts for antibiotic resistant bacteria in the studied catchment areas. A comparison with other studies on antibiotic resistances in karstic or mountainous springs highlighted the low contamination status of the model catchments studied here, most likely due to the high protection and careful management while other, less pristine catchments showed much higher antibiotic resistances. We demonstrate that studying easily accessible karstic springs allows a holistic view on large catchments concerning the extent and origin of fecal pollution as well as antibiotic resistance. This representative monitoring approach is also in line with the proposed update of the EU Groundwater Directive (GWD).

The Fate and Occurrence of Antibiotic-Resistant Bacteria and Antibiotic Resistance Genes during Advanced Wastewater Treatment and Disinfection: A Review

Antimicrobial resistance (AMR) is a serious problem for modern society, not only associated with clinical environments, but also the natural environment. Conventional wastewater treatment plants (WWTPs) are important nodes for the dissemination of antibiotic resistance to the aquatic environment since they are reservoirs of antibiotic-resistant bacteria (ARB), antibiotic resistance genes (ARGs), and antibiotic residues. WWTPs are not designed to remove these antibiotic resistance determinants from wastewater, and as a result, they are present in treated effluent, leading to environmental and public health concerns regarding wastewater disposal and reuse. Additional treatments combined with conventional WWTPs can be barriers to the spread of AMR to the environment. In order to understand the effect of wastewater treatment methods on the removal of ARB and ARGs, an extensive bibliographic study was conducted. This review summarizes the efficiency of conventional disinfection methods, tertiary wastewater treatment, and advanced oxidation processes (AOPs) to remove ARB and ARGs from wastewater. In the context of the revised Urban Wastewater Treatment Directive 91/271/EEC, further studies are needed on the removal potential of AOPs on a full-scale, as they offer great potential for the removal of ARB and ARGs with a low formation of toxic by-products compared to conventional disinfection methods.

Ciprofloxacin- and azithromycin-resistant bacteria in a wastewater treatment plant

The occurrence of antibiotic-resistant bacteria (ARB) in wastewater treatment plants (WWTPs) has become an occupational and environmental concern. WWTPs are engineered systems that treat wastewater to meet public health standards before release into the environment. The residuals, as either effluent or solids, are then discharged or beneficially recycled into the environment. Since these wastes contain a diverse array of microorganisms, some of which are resistant to commonly used antibiotics, there is a potential for these organisms to spread in the environment via residual recycling and effluent discharge. Human infections with ARB are increasing, and it is not well known how the interaction between humans and the environment plays a role in this process. WWTP workers, who are on the front lines, may come into direct contact with materials containing these microbes. This study aimed to determine the number of ARB present in both air and sewage sludges in a WWTP using nonselective media supplemented with two antibiotics (ciprofloxacin and azithromycin). The densities of total heterotrophic bacteria, ciprofloxacin-resistant bacteria, and azithromycin-resistant bacteria were 7.82 × 105 − 4.7 × 109, 7.87 × 103 − 1.05 × 108, and 2.27 × 105 − 1.16 × 109 CFU/g, respectively. The prevalence [(concentration on medium with antibiotics/concentration on medium without antibiotics) × 100] of ciprofloxacin-resistant bacteria in treated sludge was twice as low as in digested sludge and approximately three times lower than in raw sludge. For azithromycin, the prevalence of resistant bacteria in treated sludge was about the same in digested and nearly twice lower than in raw sludge. Despite a marked reduction in the mean prevalence of resistant bacteria in dewatered treated sludge for both antibiotics, these differences were not significant. The highest prevalence of antibiotic resistance was observed for azithromycin. Similarly, the prevalence of airborne azithromycin-resistant bacteria inside the belt filter press room (BFPR) was nearly seven times higher than the prevalence of airborne ciprofloxacin-resistant bacteria. These concentrations of ARB were not negligible and may represent an exposure pathway for some workers in WWTPs.

Occurrence of antibiotic resistant bacteria causing UTIs among children under school age in Soran city, North of Iraq

The current study was carried out to investigate the occurrence of multidrug resistant uropathogens among children under school age (six years old) in Soran city, North of Iraq. A total number of 200 urine samples were taken from children under six years old suffering from UTIs, attending Ashti hospital and Childbirth hospitals in Soran city from July 2017 to march 2018. High frequency of UTIs was among children less than two years old (34.3%) and incidence of UTIs was significantly higher in little girls (57.1%) than in little boys. 70 bacterial uropathogens have benn isolated while 130 samples showed negative culture. The diagnosis of isolates showed that the most common uropathogen was E. coli constituting 27 (38.6%), while others included; Staphylococcus aureus 13 (18.6%), coagulase negative staphylococci 8 (11.4)%, Klebsiella pneumonia 7(10%), Enterococcus faecalis 6 (8.6%), Streptococcus spp. 4 (5.7%), Pseudomonas aeruginosa 2 (2.9%), Staphylococcus saprophyticus 2 (2.9%) and Proteus vulgaris 1 (1.4%). Most of uropathogenic isolates have resisted ampicillin, ceftazidime, ceftriaxone and cefotaxime. Other antibiotics differently showed moderate susceptibilities. The most effective antibiotics were quinolones (ciprofloxacin and levofloxacin) and carbapenems (impenem and meropenem) which showed high susceptibility percentages on all isolates under study. Six multidrug have been chosen resistant isolates to detect the presence of qnrA, qnrB, qnrS and blaKPC responsible for quinolones and carbapenem resistance by using RABD-PCR. The DNA profile showed that only the isolate K 61 (Klebsiella pneumoniae) was bearing qnrB.

Development of analytical method for veterinary antibiotics and monitoring of residuals in agricultural environment

Veterinary antibiotics (VAs) administered to livestock are introduced into the soil through livestock manure and compost. These antibiotics can run off to surface water or leach into groundwater during rainfall, causing problems such as antibiotic contamination or the occurrence of antibiotic-resistant bacteria. In this study, an analytical method for detecting four classes of VAs (penicillin, tetracyclines, macrolides, and sulfonamides) in river water and soil was developed, and the occurrence of residual antibiotics in the agricultural environment was monitored. Soil samples were extracted with the McIlvain buffer solution and pretreatment was conducted using solid-phase extraction, followed by liquid chromatography-tandem mass spectrometry to quantify target VAs. The results of this study showed that the recovery ranged from 62 to 121% in river water and 40.2–149.3% in soil. Among the other VAs, amoxicillin and spiramycin were observed to have low recoveries in all the samples. The method detection limit (MDL) was calculated in the range of 2.1–12.3 ng L−1 in river water and 1.2–13.2 ng kg−1 in soil, and the limit of quantification was 6.6–39.2 ng L−1 and 4.0–42.0 ng kg−1, respectively. This optimal method was then applied to measure the residual concentrations of VAs in river water, sediment, and soil samples around the Muhan watershed in Korea. A total of seven antibiotics were detected, and their concentrations ranged from 0.014 to 0.309 μg L−1in river water, and 1.45–9.04 μg kg−1 in sediment and arable soil. This method can be used to screen VAs in river water and soil and is expected to be used as primary data for examining the occurrence and fate of antibiotics in agricultural environments.

Quantification and antibiotic resistance risk assessment of chlorination-residual viable/VBNC Escherichia coli and Enterococcus in on-site hospital wastewater treatment system

On-site hospital wastewater treatment system widely applying chlorination has been regarded as an important barrier to curb the dissemination of antibiotic resistance. Chlorination-residual viable and viable but non-culturable (VBNC) bacteria probably lead to overestimate the effect of disinfection, while their antibiotic resistance risks imported from hospital effluents to municipal pipe network may be ignored. In this study, we quantified viable/VBNC Escherichia coli and Enterococcus in chlorination of an on-site hospital wastewater treatment system and assessed their antibiotic resistance risks. The numbers of viable/VBNC Escherichia coli and Enterococcus in raw wastewater were detected as high as 5.76–6.34/5.76–6.33 and 5.44–5.76/5.44–5.75 log10(cells/mL). Meanwhile, high proportions of antibiotic-resistant Escherichia coli and Enterococcus to culturable Escherichia coli and Enterococcus were observed, especially carrying ampicillin resistance (22.25–41.70 % and 28.09–54.05 %). Chlorination could remove 0.44–1.88‐/0.43–1.88- and 0.29–1.29‐/0.28–1.28-log of viable/VBNC and complete culturable Escherichia coli and Enterococcus, but cause antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) to be released outside cells, and possibly further enhance the antibiotic resistance of viable bacteria. Low detections of antibiotics suggested that the occurrence of antibiotic-resistant bacteria (ARB) may not be accompanied by the corresponding antibiotics. Different sampling months had some impacts on above results, while the results were basically stable at different sampling times of hospital daily working period. The high release rates (11.26–13.02 and 11.59–12.98 log10(cells/h)) and cumulative amounts (15.41–16.12 and 15.75–16.14 log10(cells)) of chlorination-residual viable/VBNC Escherichia coli and Enterococcus indirectly assessed the potential risks of bacterial antibiotic resistance entering municipal pipe network. Additionally, the contributions from the corresponding antibiotic ceftazidime, ciprofloxacin, and vancomycin with the cumulative amounts of 2.57–4.85, 5.73–7.50, and 5.21–7.14 kg should also be taken seriously. Residual chlorine could serve as an important signal indicator for the risk assessment.

Resistome Study in Aquatic Environments.

Since the first discovery of antibiotics, introduction of new antibiotics has been coupled with the occurrence of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). Rapid dissemination of ARB and ARGs in the aquatic environments has become a global concern. ARB and ARGs have been already disseminated in the aquatic environments via various routes. Main hosts of most of ARGs were found to belong to Gammaproteobacteria class, including clinically important potential pathogens. Transmission of ARGs also occurs by horizontal gene transfer (HGT) mechanisms between bacterial strains in the aquatic environments, resulting in ubiquity of ARGs. Thus, a few of ARGs and MGEs (e.g., strA, sul1, int1) have been suggested as indicators for global comparability of contamination level in the aquatic environments. With ARB and ARGs contamination, the occurrence of critical pathogens has been globally issued due to their widespread in the aquatic environments. Thus, active surveillance systems have been launched worldwide. In this review, we described advancement of methodologies for ARGs detection, and occurrence of ARB and ARGs and their dissemination in the aquatic environments. Even though numerous studies have been conducted for ARB and ARGs, there is still no clear strategy to tackle antibiotic resistance (AR) in the aquatic environments. At least, for consistent surveillance, a strict framework should be established for further research in the aquatic environments.

Occurrence of antibiotic-resistant bacteria and resistance genes in the urban water cycle.

This study investigates the antibiotic resistance fate in the urban water cycle, evaluating the dynamics of antibiotic-resistant bacteria (ARB) and antibiotic-resistant genes (ARGs) in three different full-scale wastewater treatment plants (WWTPs) and two drinking water treatment plants (DWTPs) located in the same geographical area (North-West of Italy). ARB (tetracycline-, ampicillin-, and sulfonamide-resistant bacteria) were quantified by plate counting and the abundances of selected ARGs (i.e., tetA, blaTEM, and sulII) and intI1 gene were measured using quantitative real-time PCR (qPCR). Higher concentrations of ARB and ARGs were observed in the WWTPs with respect to the DWTPs identifying the WWTP as hotspot for the spread of antibiotic resistances. Although a significant reduction of ARB and ARGs was observed in WWTPs and DWTPs after the treatment, none of the detected ARB or ARGs was completely removed in drinking water. The stability of the antibiotic-resistant rates between inlet and outlet associated with the reduction of relative ARG abundances underlined that both the treatments (WWTs and DWTs) did not apply any selective pressure. The overall results highlighted the importance to investigate the antibiotic resistance dynamics in aquatic ecosystems involved in urban water cycle integrating the information obtained by culture-dependent method with the culture-independent one and the need to monitor the presence of ARB and ARGs mainly in drinking water that represents a potential route of transmission to human.

Occurrence of Antibiotic Resistant Bacteria in Flours and Different Plant Powders Used in Cuisine.

In recent years, several alimentary diseases have been connected with the consumption or tasting of raw flour and dough. Microbiological quality concern is also raising due to increased consumer demand for plant powders, while some of them can be consumed without prior thermal processing. In this study, we have focused on the occurrence of antibiotic-resistant coliform bacteria and enterococci in flour, plant powder and dough from Slovak retail. Our results indicated the presence of both total and antibiotic-resistant coliform bacteria and enterococci in the flour and powder samples. Lower numbers of the total, as well as resistant bacteria, were detected in flours compared to plant powders. Coliform bacteria isolates were predominantly identified as Klebsiella spp. and Enterobacter spp. Ampicillin resistance appeared in 97% of isolates followed by chloramphenicol resistance (22%) and tetracycline resistance (17%). The presence of the blaSHV gene was confirmed in 13% of isolates. The tetA and tetE genes were present in 25% of isolates of coliform bacteria. The presence of enterococci was detected only in plant powders. Antibiotic-resistant strains were identified as the following: Enterococcus casseliflavus, E. gallinarium and E. faecium. Despite the isolates showing resistance to vancomycin, the presence of the vanA gene was not detected. The majority of antibiotic-resistant isolates belonged to the group of medium biofilm producers. None of these isolates showed efflux pump overproduction. Antibiotic-resistant coliform bacteria and enterococci were not detected in the processed doughs.

The occurrence of antibiotic-resistant bacteria on the clothes of nursery teachers in daycare centres.

AimsChildcare facilities act as microenvironments that facilitate and promote the selection, spread and transmission of antibiotic‐resistant micro‐organisms in the community. We focused on the study of antimicrobial resistance and genetic predispositions for β‐lactamase production in bacterial isolates from nursery teachers' clothing.Methods and ResultsAntimicrobial resistance of bacterial strains belonging to Enterobacteriaceae, Enterococcus, Staphylococcus spp., Pseudomonas spp. and Bacillus spp. isolated from 80 samples of nursery teachers' clothing was determined. The selected ESβL genes were found in 30 (44.1%) of 68 strains examined. The CTX‐M type ESβL determinants were detected in 15.4%, 71.5% and 42.5% of the Enterobacteriaceae, Pseudomonas and Bacillus isolates, respectively. The OXA‐type coding genes were detected only in strains of the genera Pseudomonas (57.1%) and Bacillus (48.6%). Thus, most B. cereus strains were sensitive to the recommended antibiotics used to treat infections caused by these bacteria. Methicillin resistance was phenotypically confirmed in 27 (14.6%) of 185 staphylococcal isolates. Four isolates (2.2%) were identified as MRSA. Vancomycin resistance was not observed in any of the staphylococcal and enterococci strains.ConclusionsThis study has shown that potential pathogens have been isolated from the clothing of nursery teachers, posing a risk of transmission to children. These clothes should be maintained and properly laundered to avoid cross‐contamination and the spread of multidrug‐resistant (MDR) bacteria in childcare centres.Significance and impact of the studyThis study provides insight into the route of transmission of MDR micro‐organisms through the clothing of nursery teachers, to which greater importance should be given in the future. Proper procedures for the cleaning and use of clothing in daycare centres should be clarified and standardized.

Effects of Glycyrrhiza Polysaccharides on Chickens' Intestinal Health and Homeostasis

The overuse of antibiotics in poultry farming causes the accumulation of drug residue in animals' bodies and the occurrence of antibiotic-resistant bacteria, which not only compromise animals' health but ultimately endanger human health. Thus, there is an urgent need for a novel poultry feed additive to substitute for excessive antibiotics. Glycyrrhiza polysaccharides (GPS) derived from Chinese licorice have shown promising immunomodulatory effects in previous studies. The present study investigated the pharmacological effects of GPS on poultry intestines to assess whether it can be used as a feed additive. The results show that GPS can increase production of sIgA, promote the secretion activity of goblet cells, alter the gut microbial composition and lead to changes in short-chain fatty acids. GPS also elevated both Th1 and Th2 immune responses by facilitating the expression of IL-2, IL-4, IL-1β, and IFN-γ while increasing the proportion of both CD4+ and CD8+ cells in the intestine. Moreover, the results of 16S rRNA gene sequencing showed that GPS could significantly change intestinal microbiota composition in the intestine, evidenced by the increased proportion of Bacteroides, Butyricicoccus and Eisenbergiella, as well as a decreased portion of Erysipelatoclostridium, leading to a healthier intestinal microbiota composition for the host. Taken together, it can be concluded that GPS is safe to use as a novel feed additive that can be used as an alternative to prophylactic antibiotics in poultry feeding.

Occurrence of antibiotic resistant bacteria and antibiotic resistant genes in rivers found in Anambra state, Nigeria

The study involves the analysis of water samples obtained through simple random sampling (SRS) technique from selected rivers in Anambra State, Nigeria for presence of antibiotic resistant bacteria and antibiotic resisistant genes. The high morbidity and mortality rate among the populace calls for this research. The most probable number (MPN) technique was utilized. Antibiotic susceptibility test, molecular characterization and plasmid profiling tests were carried out. The result of the MPN test indicated that coliform bacteria mostly Escherichia coli occurred predominantly in the water samples connoting effective confirmation of faecal contamination of the rivers. E. coli strains were distinguished by their ability to give colour changes on some lactose broth tubes impregnated with the water samples, surviving high temperatures of 45℃. Antibiotic susceptibility test results revealed that the E. coli isolates were resistant to all the seven antibiotics used namely, clindamycin, gentamycin, ciprofloxacin, erythromycin, sulfonamides, ampicillin and tetracycline. The results of molecular characterization indicated that the most prevalent resistant genes detected in the water samples were the tet A, tet B, sul1 and sul2 of the E. coli strains. The results of the plasmid profiling of the isolates revealed the presence of plasmids on the identified genes. The inferential statistics was employed during data analysis. It was therefore evident that antibiotic resistant bacteria and antibiotic resistant genes occurred in the rivers studied. This then calls for concerted efforts to checkmate this occurrence with a view to promoting the good health of all and sundry.

Occurrence of antibiotic resistant bacteria and antibiotic resistant genes in rivers found in Anambra state, Nigeria

Occurrence of antibiotic resistant bacteria and antibiotic resistant genes in rivers found in Anambra state, Nigeria

Occurrence of Antibiotic Resistant Bacteria in Urban Karst Groundwater Systems

Antibiotic resistance is a global concern for human, animal, and environmental health. Many studies have identified wastewater treatment plants and surface waters as major reservoirs of antibiotic resistant bacteria (ARB) and genes (ARGs). Yet their prevalence in urban karst groundwater systems remains largely unexplored. Considering the extent of karst groundwater use globally, and the growing urban areas in these regions, there is an urgent need to understand antibiotic resistance in karst systems to protect source water and human health. This study evaluated the prevalence of ARGs associated with resistance phenotypes at 10 urban karst features in Bowling Green, Kentucky weekly for 46 weeks. To expand the understanding of prevalence in urban karst, a spot sampling of 45 sites in the Tampa Bay Metropolitan area, Florida was also conducted. Specifically, this study considered tetracycline and extended spectrum beta-lactamase (ESBLs) producing, including third generation cephalosporin, resistant E. coli, and tetracycline and macrolide resistant Enterococcus spp. across the 443 Kentucky and 45 Florida samples. A consistent prevalence of clinically relevant and urban associated ARGs were found throughout the urban karst systems, regardless of varying urban development, karst geology, climate, or landuse. These findings indicate urban karst groundwater as a reservoir for antibiotic resistance, potentially threatening human health.

Analysis of the Occurrence of Antibiotic Resistant Bacteria in the Hospital's Effluent and its Receiving Environment.

The use of antibiotics on a regular and excessive basis is a major factor in the spread of antibiotic-resistant bacteria. Patients discharge un-metabolized or relatively low doses of non-metabolized antibiotics through urine and stool, which might enter into the environment through sewage disposal and promote the emergence of antibiotic resistant bacteria. This study is designed to investigate how excessive use of antibiotics in the hospital sector and their release into hospital wastes contribute to the spread of antibiotic-resistant bacteria in different environmental settings. In this study, liquid hospital waste was collected from the sewage of Chittagong Medical College Hospital (CMCH), Bangladesh as well as from its distribution position in Chittagong city, Bangladesh. A total of 5 samples were collected from different positions in Chittagong city, including CMCH liquid waste. After collection, total bacteria and total cefixime resistant bacteria were counted by the total viable count (TVC) method. The result of bacteriological enumeration showed that a high magnitude of cefixime-resistant bacteria were available in all the hospital’s associated waste samples. The highest proportion of cefixime resistant bacteria (23.35%) was found in sample 2, whereas 17.4%, 7.6%, 5%, and 1.32% were found in samples 1, 3, 4, and 5, respectively. The total number of cefixime-resistant bacteria decreased with the increase in distance between the sample collection site and the hospital drain. This means that resistant bacteria developed in the hospital effluent are transferred to the environmental distribution sites.