Diversity of Multidrug-Resistant Bacteria in an Urbanized River: A Case Study of the Potential Risks from Combined Sewage Overflows

Wastewater contamination and urbanization contribute to the spread of antibiotic resistance in aquatic environments. This is a particular concern in areas receiving chronic pollution of untreated waste via combined sewer overflow (CSO) events. The goal of this study was to expand knowledge of CSO impacts, with a specific focus on multidrug resistance. We sampled a CSO-impacted segment of the James River (Virginia, USA) during both clear weather and an active overflow event and compared it to an unimpacted upstream site. Bacteria resistant to ampicillin, streptomycin, and tetracycline were isolated from all samples. Ampicillin resistance was particularly abundant, especially during the CSO event, so these isolates were studied further using disk susceptibility tests to assess multidrug resistance. During a CSO overflow event, 82% of these isolates were resistant to five or more antibiotics, and 44% were resistant to seven or more. The latter statistic contrasts starkly with the upstream reference site, where only 4% of isolates displayed resistance to more than seven antibiotics. DNA sequencing (16S rRNA gene) revealed that ~35% of our isolates were opportunistic pathogens, comprised primarily of the genera Stenotrophomonas, Pseudomonas, and Chryseobacterium. Together, these results demonstrate that CSOs can be a significant source of viable clinically-relevant bacteria to the natural environment and that multidrug resistance is an important understudied component of the environmental spread of antibiotic resistance.

Download Full-text

Characterization of bacteria and antibiotic resistance in commercially-produced cheeses sold in China

Journal of Food Protection ◽

10.4315/jfp-21-198 ◽

2021 ◽

Author(s):

Jinghui Yao ◽

Jing Gao ◽

Jianming Guo ◽

Hengan Wang ◽

En Zhang ◽

...

Keyword(s):

Antibiotic Resistance ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Acquired Resistance ◽

Antibiotic Resistance Genes ◽

16S Rrna Gene Sequencing ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Rrna Gene ◽

Rrna Gene Sequencing

The consumption of cheese in China is increasing rapidly. Little is known about the microbiota, the presence of antibiotic-resistant bacteria, or the distribution of antibiotic resistance genes (ARGs) in commercially-produced cheeses sold in China. These are important criteria for evaluating quality and safety. Thus, this study assessed the metagenomics of fifteen types of cheese using 16S rRNA gene sequencing. Fourteen bacterial genera were detected. Lactococcus , Lactobacillus , and Streptococcus were dominant based on numbers of sequence reads. Multidrug-resistant lactic acid bacteria were isolated from most of the types of cheese. The isolates showed 100% and 91.7% resistance to streptomycin and sulfamethoxazole, respectively, and genes involved in acquired resistance to streptomycin ( strB) and sulfonamides ( sul2) were detected with high frequency. To analyze the distribution of ARGs in the cheeses in overall, 309 ARGs from eight categories of ARG and nine transposase genes were profiled. A total of 169 ARGs were detected in the 15 cheeses; their occurrence and abundance varied significantly between cheeses. Our study demonstrates that there is various diversity of the bacteria and ARGs in cheeses sold in China. The risks associated with multidrug resistance of dominant lactic acid bacteria are of great concern.

Download Full-text

Multidrug Resistance (MDR) and Collateral Sensitivity in Bacteria, with Special Attention to Genetic and Evolutionary Aspects and to the Perspectives of Antimicrobial Peptides—A Review

Pathogens ◽

10.3390/pathogens9070522 ◽

2020 ◽

Vol 9 (7) ◽

pp. 522

Author(s):

András Fodor ◽

Birhan Addisie Abate ◽

Péter Deák ◽

László Fodor ◽

Ervin Gyenge ◽

...

Keyword(s):

Antibiotic Resistance ◽

Multidrug Resistance ◽

Antimicrobial Peptides ◽

Resistance Genes ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Mobility Patterns ◽

Collateral Sensitivity ◽

Resistance Evolution ◽

Antimicrobial Peptide Resistance

Antibiotic poly-resistance (multidrug-, extreme-, and pan-drug resistance) is controlled by adaptive evolution. Darwinian and Lamarckian interpretations of resistance evolution are discussed. Arguments for, and against, pessimistic forecasts on a fatal “post-antibiotic era” are evaluated. In commensal niches, the appearance of a new antibiotic resistance often reduces fitness, but compensatory mutations may counteract this tendency. The appearance of new antibiotic resistance is frequently accompanied by a collateral sensitivity to other resistances. Organisms with an expanding open pan-genome, such as Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae, can withstand an increased number of resistances by exploiting their evolutionary plasticity and disseminating clonally or poly-clonally. Multidrug-resistant pathogen clones can become predominant under antibiotic stress conditions but, under the influence of negative frequency-dependent selection, are prevented from rising to dominance in a population in a commensal niche. Antimicrobial peptides have a great potential to combat multidrug resistance, since antibiotic-resistant bacteria have shown a high frequency of collateral sensitivity to antimicrobial peptides. In addition, the mobility patterns of antibiotic resistance, and antimicrobial peptide resistance, genes are completely different. The integron trade in commensal niches is fortunately limited by the species-specificity of resistance genes. Hence, we theorize that the suggested post-antibiotic era has not yet come, and indeed might never come.

Download Full-text

Insights into Antagonistic Interactions of Multidrug Resistant Bacteria in Mangrove Sediments from the South Indian State of Kerala

Microorganisms ◽

10.3390/microorganisms7120678 ◽

2019 ◽

Vol 7 (12) ◽

pp. 678 ◽

Cited By ~ 1

Author(s):

Madangchanok Imchen ◽

Ravali Krishna Vennapu ◽

Preetam Ghosh ◽

Ranjith Kumavath

Keyword(s):

Antibiotic Resistance ◽

Biofilm Formation ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Rrna Gene ◽

Natural Setting ◽

Antagonist Activity ◽

Gram Positive ◽

Gram Negative ◽

South Indian

Antibiotic resistance is a global issue which is magnified by interspecies horizontal gene transfer. Understanding antibiotic resistance in bacteria in a natural setting is crucial to check whether they are multidrug resistant (MDR) and possibly avoid outbreaks. In this study, we have isolated several antibiotic-resistant bacteria (ARB) (n = 128) from the mangroves in Kerala, India. ARBs were distributed based on antibiotics (p = 1.6 × 10−5). The 16S rRNA gene characterization revealed dominance by Bacillaceae (45%), Planococcaceae (22.5%), and Enterobacteriaceae (17.5%). A high proportion of the isolates were MDR (75%) with maximum resistance to methicillin (70%). Four isolates affiliated to plant-growth promoters, probiotics, food, and human pathogens were resistant to all antibiotics indicating the seriousness and prevalence of MDR. A significant correlation (R = 0.66; p = 2.5 × 10−6) was observed between MDR and biofilm formation. Antagonist activity was observed in 62.5% isolates. Gram-positive isolates were more susceptible to antagonism (75.86%) than gram-negative (36.36%) isolates. Antagonism interactions against gram-negative isolates were lower (9.42%) when compared to gram-positive isolates (89.85%). Such strong antagonist activity can be harnessed for inspection of novel antimicrobial mechanisms and drugs. Our study shows that MDR with strong biofilm formation is prevalent in natural habitat and if acquired by deadly pathogens may create havoc in public health.

Download Full-text

The prevalence and identification of multidrug-resistant bacteria in adjacent ecological systems in the Hocking Hills region of Appalachia

Fine Focus ◽

10.33043/ff.6.1.54-75 ◽

2020 ◽

Vol 6 (1) ◽

pp. 54-75

Author(s):

Orion D. Brock ◽

Jennifer R. Larson

Keyword(s):

Antibiotic Resistance ◽

Multidrug Resistance ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Clinical Settings ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant ◽

Ecological Zones ◽

Healthcare Settings ◽

16S Gene

Multidrug resistance in clinical settings is a major threat to human health, but very little is known regarding the prevalence of multidrug-resistant organisms in the natural environment. Studying antibiotic resistance in the environment is important for understanding the transfer of resistance between environmental microorganisms and those found in healthcare settings. In this study, soil samples from seven adjacent ecological zones were evaluated to determine if there were differences in the amount and types of antibiotic-resistant bacteria present. We hypothesized that we would find antibiotic-resistant bacteria in all ecological zones studied and that these bacteria would be unique to their specific niche. Several resistant organisms from each site were also tested for multidrug resistance and subsequently identified through DNA sequencing of the 16S gene. Antibiotic resistance was discovered in all sites at varying percentages. Some forms of bacteria were present at all sites, but there were differences in types of resistant bacteria found between sites. Six different genera of bacteria were identified, and multidrug resistance was found in all the isolates studied. Our findings indicate that multidrug resistance is prevalent in many different types of environments, including those that have never been directly used for agricultural or urban development.

Download Full-text

Testudines as Sentinels for Monitoring the Dissemination of Antibiotic Resistance in Marine Environments: An Integrative Review

Antibiotics ◽

10.3390/antibiotics10070775 ◽

2021 ◽

Vol 10 (7) ◽

pp. 775

Author(s):

Kezia Drane ◽

Roger Huerlimann ◽

Michelle Power ◽

Anna Whelan ◽

Ellen Ariel ◽

...

Keyword(s):

Antibiotic Resistance ◽

Anthropogenic Activities ◽

Sea Turtles ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Marine Environments ◽

Beta Lactam ◽

Antibiotic Resistant ◽

Sensitivity Tests ◽

Standard Culture

Dissemination of antibiotic resistance (AR) in marine environments is a global concern with a propensity to affect public health and many ecosystems worldwide. We evaluated the use of sea turtles as sentinel species for monitoring AR in marine environments. In this field, antibiotic-resistant bacteria have been commonly identified by using standard culture and sensitivity tests, leading to an overrepresentation of specific, culturable bacterial classes in the available literature. AR was detected against all major antibiotic classes, but the highest cumulative global frequency of resistance in all represented geographical sites was against the beta-lactam class by a two-fold difference compared to all other antibiotics. Wastewater facilities and turtle rehabilitation centres were associated with higher incidences of multidrug-resistant bacteria (MDRB) accounting for an average of 58% and 49% of resistant isolates, respectively. Furthermore, a relatively similar prevalence of MDRB was seen in all studied locations. These data suggest that anthropogenically driven selection pressures for the development of AR in sea turtles and marine environments are relatively similar worldwide. There is a need, however, to establish direct demonstrable associations between AR in sea turtles in their respective marine environments with wastewater facilities and other anthropogenic activities worldwide.

Download Full-text

Comparison of Antibiotic Resistance Profile of Escherichia coli between Pristine and Human-Impacted Sites in a River

Antibiotics ◽

10.3390/antibiotics10050575 ◽

2021 ◽

Vol 10 (5) ◽

pp. 575

Author(s):

Emi Nishimura ◽

Masateru Nishiyama ◽

Kei Nukazawa ◽

Yoshihiro Suzuki

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Resistant Bacteria ◽

Downstream Site ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant ◽

Upstream Site ◽

Resistance Profile ◽

Antibiotic Resistance Profile ◽

Significant Difference

Information on the actual existence of antibiotic-resistant bacteria in rivers where sewage, urban wastewater, and livestock wastewater do not load is essential to prevent the spread of antibiotic-resistant bacteria in water environments. This study compared the antibiotic resistance profile of Escherichia coli upstream and downstream of human habitation. The survey was conducted in the summer, winter, and spring seasons. Resistance to one or more antibiotics at upstream and downstream sites was on average 18% and 20%, respectively, and no significant difference was observed between the survey sites. The resistance rates at the upstream site (total of 98 isolated strains) to each antibiotic were cefazolin 17%, tetracycline 12%, and ampicillin 8%, in descending order. Conversely, for the downstream site (total of 89 isolated strains), the rates were ampicillin 16%, cefazolin 16%, and tetracycline 1% in descending order. The resistance rate of tetracycline in the downstream site was significantly lower than that of the upstream site. Furthermore, phylogenetic analysis revealed that many strains showed different resistance profiles even in the same cluster of the Pulsed-Field Gel Electrophoresis (PFGE) pattern. Moreover, the resistance profiles differed in the same cluster of the upstream and the downstream sites. In flowing from the upstream to the downstream site, it is plausible that E. coli transmitted or lacked the antibiotic resistance gene.

Download Full-text

Antibiotic Resistance in Pediatric Infections: Global Emerging Threats, Predicting the Near Future

Antibiotics ◽

10.3390/antibiotics10040393 ◽

2021 ◽

Vol 10 (4) ◽

pp. 393

Author(s):

Alessandra Romandini ◽

Arianna Pani ◽

Paolo Andrea Schenardi ◽

Giulia Angela Carla Pattarino ◽

Costantino De Giacomo ◽

...

Keyword(s):

Antibiotic Resistance ◽

Pediatric Population ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Pediatric Age ◽

Carbapenem Resistant ◽

Pediatric Infections ◽

Surgical Treatments ◽

Developing System ◽

Near Future

Antibiotic resistance is a public health threat of the utmost importance, especially when it comes to children: according to WHO data, infections caused by multidrug resistant bacteria produce 700,000 deaths across all ages, of which around 200,000 are newborns. This surging issue has multipronged roots that are specific to the pediatric age. For instance, the problematic overuse and misuse of antibiotics (for wrong diagnoses and indications, or at wrong dosage) is also fueled by the lack of pediatric-specific data and trials. The ever-evolving nature of this age group also poses another issue: the partly age-dependent changes of a developing system of cytochromes determine a rather diverse population in terms of biochemical characteristics and pharmacokinetics profiles, hard to easily codify in an age- or weight-dependent dosage. The pediatric population is also penalized by the contraindications of tetracyclines and fluoroquinolones, and by congenital malformations which often require repeated hospitalizations and pharmacological and surgical treatments from a very young age. Emerging threats for the pediatric age are MRSA, VRSA, ESBL-producing Enterobacteriaceae, carbapenem-resistant Enterobacteriaceae and the alarming colistin resistance. Urgent actions need to be taken in order to step back from a now likely post-antibiotic era, where simple infections might cause infant death once again.

Download Full-text

Prevalence of Antibiotic-Resistant Bacteria ESKAPE among Healthy People Estimated by Monitoring of Municipal Wastewater

Antibiotics ◽

10.3390/antibiotics10050495 ◽

2021 ◽

Vol 10 (5) ◽

pp. 495

Author(s):

Masateru Nishiyama ◽

Susan Praise ◽

Keiichi Tsurumaki ◽

Hiroaki Baba ◽

Hajime Kanamori ◽

...

Keyword(s):

Antibiotic Resistance ◽

General Population ◽

Municipal Wastewater ◽

Treatment Plant ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Municipal Wastewater Treatment ◽

Antibiotic Resistant ◽

Carbapenem Resistant ◽

Wastewater Samples

There is increasing attention toward factors that potentially contribute to antibiotic resistance (AR), as well as an interest in exploring the emergence and occurrence of antibiotic resistance bacteria (ARB). We monitored six ARBs that cause hospital outbreaks in wastewater influent to highlight the presence of these ARBs in the general population. We analyzed wastewater samples from a municipal wastewater treatment plant (MWWTP) and hospital wastewater (HW) for six species of ARB: Carbapenem-resistant Enterobacteria (CARBA), extended-spectrum β-lactamase producing Enterobacteria (ESBL), multidrug-resistant Acinetobacter (MDRA), multidrug-resistant Pseudomonas aeruginosa (MDRP), methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant Enterococci (VRE). We registered a high percentage of ARBs in MWWTP samples (>66%) for all ARBs except for MDRP, indicating a high prevalence in the population. Percentages in HW samples were low (<78%), and no VRE was detected throughout the study. CARBA and ESBL were detected in all wastewater samples, whereas MDRA and MRSA had a high abundance. This result demonstrated the functionality of using raw wastewater at MWWTP to monitor the presence and extent of ARB in healthy populations. This kind of surveillance will contribute to strengthening the efforts toward reducing ARBs through the detection of ARBs to which the general population is exposed.

Download Full-text

Prevalence of Mastitis and Antibiotic Resistance of Bacterial Isolates from CMT Positive Milk Samples Obtained from Dairy Cows, Camels, and Goats in Two Pastoral Districts in Southern Ethiopia

Animals ◽

10.3390/ani11061530 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1530

Author(s):

Amanuel Balemi ◽

Balako Gumi ◽

Kebede Amenu ◽

Sisay Girma ◽

Muuz Gebru ◽

...

Keyword(s):

Antibiotic Resistance ◽

Dairy Cows ◽

Raw Milk ◽

Multidrug Resistant ◽

Southern Ethiopia ◽

Resistant Bacteria ◽

Coagulase Negative Staphylococcus ◽

Bacterial Isolates ◽

E Coli ◽

Milk Samples

A study was carried out from August 2017 to February 2018 on lactating dairy cows, one-humped dromedary camels, and goats to determine mastitis in the Bule Hora and Dugda Dawa districts of in Southern Ethiopia. Milk samples from 564 udder quarters and udder halves from 171 animals consisting of 60 dairy cows, 51 camels, and 60 goats were tested for mastitis. Sixty-four positive udder milk samples were cultured, and bacterial mastitis pathogens were isolated and identified. The antibiotic resistance of bacterial isolates from milk with mastitis was tested against nine antimicrobials commonly used in the study area. Cow- and quarter-level prevalence of mastitis in dairy cows, camels, and goats was 33.3%, 26.3%, and 25% and 17.6%, 14.5%, and 20%, respectively. In cattle, the prevalence was significantly higher in Dugda Dawa than in Bule Hora. Major bacterial isolates were coagulase-negative Staphylococcus species (39.1%), S. aureus (17.2%), S. hyicus (14.1%), and S. intermedius and Escherichia coli (9.4% each). In camels, udder abnormality and mastitis were significantly higher in late lactation than in early lactation. Mastitis tends to increase with parity in camels. E. coli isolates were highly resistant to spectinomycin, vancomycin, and doxycycline, whereas most S. aureus isolates were multidrug-resistant. Most of the rural and periurban communities in this area consume raw milk, which indicates a high risk of infection with multidrug-resistant bacteria. We recommend a community-focused training program to improve community awareness of the need to boil milk and the risk of raw milk consumption.

Download Full-text

Environmental Spread of New Delhi Metallo-β-Lactamase-1-Producing Multidrug-Resistant Bacteria in Dhaka, Bangladesh

Applied and Environmental Microbiology ◽

10.1128/aem.00793-17 ◽

2017 ◽

Vol 83 (15) ◽

Cited By ~ 32

Author(s):

Mohammad Aminul Islam ◽

Moydul Islam ◽

Rashedul Hasan ◽

M. Iqbal Hossain ◽

Ashikun Nabi ◽

...

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Tap Water ◽

Antibiotic Resistance Genes ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

New Delhi ◽

Multidrug Resistant Bacteria ◽

Content Type ◽

Wastewater Samples

ABSTRACT Resistance to carbapenem antibiotics through the production of New Delhi metallo-β-lactamase-1 (NDM-1) constitutes an emerging challenge in the treatment of bacterial infections. To monitor the possible source of the spread of these organisms in Dhaka, Bangladesh, we conducted a comparative analysis of wastewater samples from hospital-adjacent areas (HAR) and from community areas (COM), as well as public tap water samples, for the occurrence and characteristics of NDM-1-producing bacteria. Of 72 HAR samples tested, 51 (71%) samples were positive for NDM-1-producing bacteria, as evidenced by phenotypic tests and the presence of the bla NDM-1 gene, compared to 5 of 41 (12.1%) samples from COM samples (P < 0.001). All tap water samples were negative for NDM-1-producing bacteria. Klebsiella pneumoniae (44%) was the predominant bacterial species among bla NDM-1-positive isolates, followed by Escherichia coli (29%), Acinetobacter spp. (15%), and Enterobacter spp. (9%). These bacteria were also positive for one or more other antibiotic resistance genes, including bla CTX-M-1 (80%), bla CTX-M-15 (63%), bla TEM (76%), bla SHV (33%), bla CMY-2 (16%), bla OXA-48-like (2%), bla OXA-1 (53%), and bla OXA-47-like (60%) genes. Around 40% of the isolates contained a qnr gene, while 50% had 16S rRNA methylase genes. The majority of isolates hosted multiple plasmids, and plasmids of 30 to 50 MDa carrying bla NDM-1 were self-transmissible. Our results highlight a number of issues related to the characteristics and source of spread of multidrug-resistant bacteria as a potential public health threat. In view of the existing practice of discharging untreated liquid waste into the environment, hospitals in Dhaka city contribute to the potential dissemination of NDM-1-producing bacteria into the community. IMPORTANCE Infections caused by carbapenemase-producing Enterobacteriaceae are extremely difficult to manage due to their marked resistance to a wide range of antibiotics. NDM-1 is the most recently described carbapenemase, and the bla NDM-1 gene, which encodes NDM-1, is located on self-transmissible plasmids that also carry a considerable number of other antibiotic resistance genes. The present study shows a high prevalence of NDM-1-producing organisms in the wastewater samples from hospital-adjacent areas as a potential source for the spread of these organisms to community areas in Dhaka, Bangladesh. The study also examines the characteristics of the isolates and their potential to horizontally transmit the resistance determinants. The significance of our research is in identifying the mode of spread of multiple-antibiotic-resistant organisms, which will allow the development of containment measures, leading to broader impacts in reducing their spread to the community.

Download Full-text