Antimicrobial Resistance Profiles of Bacteria Isolated from the Nasal Cavity of Camels in Samburu, Nakuru, and Isiolo Counties of Kenya

This study was designed to determine antimicrobial resistance profiles of bacteria isolated from the nasal cavity of healthy camels. A total of 255 nasal samples (swabs) were collected in Isiolo, Samburu, and Nakuru counties, Kenya, from which 404 bacterial isolates belonging to various genera and species were recovered. The bacterial isolates included Bacillus (39.60%), coagulase-negative Staphylococcus (29.95%), Streptococcus species other than Streptococcus agalactiae (25.74%), coagulase-positive Staphylococcus (3.96%), and Streptococcus agalactiae (0.74%). Isolates were most susceptible to Gentamicin (95.8%), followed by Tetracycline (90.5%), Kanamycin and Chloramphenicol (each at 85.3%), Sulphamethoxazole (84.2%), Co-trimoxazole (82.1%), Ampicillin (78.9%), and finally Streptomycin (76.8%). This translated to low resistance levels. Multidrug resistance was also reported in 30.5% of the isolates tested. Even though the antibiotic resistance demonstrated in this study is low, the observation is significant, since the few resistant normal flora could be harboring resistance genes which can be transferred to pathogenic bacteria within the animal, to other animals’ bacteria and, most seriously, to human pathogens.

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The shared resistome of human and pig microbiota is mobilized by distinct genetic elements

Applied and Environmental Microbiology ◽

10.1128/aem.01910-20 ◽

2020 ◽

Author(s):

Chao Wang ◽

Yuqin Song ◽

Na Tang ◽

Gang Zhang ◽

Sébastien Olivier Leclercq ◽

...

Keyword(s):

Antibiotic Resistance ◽

Intestinal Microbiota ◽

Resistance Genes ◽

Pathogenic Bacteria ◽

Antibiotic Resistance Genes ◽

Mobile Genetic Elements ◽

Human Pathogens ◽

Genetic Elements ◽

Metagenomics Data ◽

Genetic Context

The extensive use of antibiotics in hospitals and in the animal breeding industry has promoted antibiotic resistance in bacteria, which resulted in the emergence of a large number of antibiotic resistance genes in the intestinal tract of human and farmed animals. Genetic exchange of resistance genes between the two ecosystems is now well documented for pathogenic bacteria, but the repertoire of shared resistance genes in the commensal bacterial community and by which genetic modules they are disseminated are still unclear. By analyzing metagenomics data of human and pig intestinal samples both collected in Shenzhen, China, a set of 27 highly prevalent antibiotic resistance genes was found to be shared between human and pig intestinal microbiota. The mobile genetic context for 11 of these core antibiotic resistance genes could be identified by mining their carrying scaffolds constructed from the two datasets, leading to the detection of seven integrative and conjugative/mobilizable elements and two IS-related transposons. The comparison of the relative abundances between these detected mobile genetic elements and their associated antibiotic resistance genes revealed that for many genes, the estimated contribution of the mobile elements to the gene abundance differs strikingly depending on the host. These findings indicate that although some antibiotic resistance genes are ubiquitous across microbiota of human and pig populations, they probably relied on different genetic elements for their dissemination within each population. IMPORTANCE There is growing concern that antibiotic resistance genes could spread from the husbandry environment to human pathogens through dissemination mediated by mobile genetic elements. In this study, we investigated the contribution of mobile genetic elements to the abundance of highly prevalent antibiotic resistance genes found in commensal bacteria of both human and pig intestinal microbiota originating from the same region. Our results reveal that for most of these antibiotic resistance genes, the abundance is not explained by the same mobile genetic element in each host, suggesting that the human and pig microbial communities promoted a different set of mobile genetic carriers for the same antibiotic resistance genes. These results deepen our understanding of the dissemination of antibiotic resistance genes among and between human and pig gut microbiota.

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Selection of a Multidrug Resistance Plasmid by Sublethal Levels of Antibiotics and Heavy Metals

mBio ◽

10.1128/mbio.01918-14 ◽

2014 ◽

Vol 5 (5) ◽

Cited By ~ 240

Author(s):

Erik Gullberg ◽

Lisa M. Albrecht ◽

Christoffer Karlsson ◽

Linus Sandegren ◽

Dan I. Andersson

Keyword(s):

Heavy Metals ◽

Antibiotic Resistance ◽

Multidrug Resistance ◽

Resistance Genes ◽

Pathogenic Bacteria ◽

Content Type ◽

Metal Levels ◽

Resistance Plasmids ◽

Low Levels ◽

Selection Of

ABSTRACTHow sublethal levels of antibiotics and heavy metals select for clinically important multidrug resistance plasmids is largely unknown. Carriage of plasmids generally confers substantial fitness costs, implying that for the plasmid-carrying bacteria to be maintained in the population, the plasmid cost needs to be balanced by a selective pressure conferred by, for example, antibiotics or heavy metals. We studied the effects of low levels of antibiotics and heavy metals on the selective maintenance of a 220-kbp extended-spectrum β-lactamase (ESBL) plasmid identified in a hospital outbreak ofKlebsiella pneumoniaeandEscherichia coli. The concentrations of antibiotics and heavy metals required to maintain plasmid-carrying bacteria, the minimal selective concentrations (MSCs), were in all cases below (almost up to 140-fold) the MIC of the plasmid-free susceptible bacteria. This finding indicates that the very low antibiotic and heavy metal levels found in polluted environments and in treated humans and animals might be sufficiently high to maintain multiresistance plasmids. When resistance genes were moved from the plasmid to the chromosome, the MSC decreased, showing that MSC for a specific resistance conditionally depends on genetic context. This finding suggests that a cost-free resistance could be maintained in a population by an infinitesimally low concentration of antibiotic. By studying the effect of combinations of several compounds, it was observed that for certain combinations of drugs each new compound added lowered the minimal selective concentration of the others. This combination effect could be a significant factor in the selection of multidrug resistance plasmids/bacterial clones in complex multidrug environments.IMPORTANCEAntibiotic resistance is in many pathogenic bacteria caused by genes that are carried on large conjugative plasmids. These plasmids typically contain multiple antibiotic resistance genes as well as genes that confer resistance to biocides and heavy metals. In this report, we show that very low concentrations of single antibiotics and heavy metals or combinations of compounds can select for a large plasmid that carries resistance to aminoglycosides, β-lactams, tetracycline, macrolides, trimethoprim, sulfonamide, silver, copper, and arsenic. Our findings suggest that the low levels of antibiotics and heavy metals present in polluted external environments and in treated animals and humans could allow for selection and enrichment of bacteria with multiresistance plasmids and thereby contribute to the emergence, maintenance, and transmission of antibiotic-resistant disease-causing bacteria.

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Detection and prevalence of antimicrobial resistance genes in Campylobacter spp. isolated from chickens and humans

Onderstepoort Journal of Veterinary Research ◽

10.4102/ojvr.v84i1.1411 ◽

2017 ◽

Vol 84 (1) ◽

Cited By ~ 13

Author(s):

Samantha Reddy ◽

Oliver T. Zishiri

Keyword(s):

Antibiotic Resistance ◽

Antimicrobial Resistance ◽

Resistance Genes ◽

Pathogenic Bacteria ◽

Antibiotic Resistance Genes ◽

Quinolone Resistance ◽

Campylobacter Coli ◽

Antimicrobial Resistance Genes ◽

Campylobacter Spp ◽

Clinical Cases

Campylobacter spp. are common pathogenic bacteria in both veterinary and human medicine. Infections caused by Campylobacter spp. are usually treated using antibiotics. However, the injudicious use of antibiotics has been proven to spearhead the emergence of antibiotic resistance. The purpose of this study was to detect the prevalence of antibiotic resistance genes in Campylobacter spp. isolated from chickens and human clinical cases in South Africa. One hundred and sixty one isolates of Campylobacter jejuni and Campylobacter coli were collected from chickens and human clinical cases and then screened for the presence of antimicrobial resistance genes. We observed a wide distribution of the tetO gene, which confers resistance to tetracycline. The gyrA genes that are responsible quinolone resistance were also detected. Finally, our study also detected the presence of the blaOXA-61, which is associated with ampicillin resistance. There was a higher (p < 0.05) prevalence of the studied antimicrobial resistance genes in chicken faeces compared with human clinical isolates. The tetO gene was the most prevalent gene detected, which was isolated at 64% and 68% from human and chicken isolates, respectively. The presence of gyrA genes was significantly (p < 0.05) associated with quinolone resistance. In conclusion, this study demonstrated the presence of gyrA (235 bp), gyrA (270 bp), blaOXA-61 and tetO antimicrobial resistance genes in C. jejuni and C. coli isolated from chickens and human clinical cases. This indicates that Campylobacter spp. have the potential of resistance to a number of antibiotic classes.

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Biosolids as a Source of Antibiotic Resistance Plasmids for Commensal and Pathogenic Bacteria

Frontiers in Microbiology ◽

10.3389/fmicb.2021.606409 ◽

2021 ◽

Vol 12 ◽

Author(s):

Aaron Law ◽

Olubunmi Solano ◽

Celeste J. Brown ◽

Samuel S. Hunter ◽

Matt Fagnan ◽

...

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Pathogenic Bacteria ◽

Treatment Plant ◽

Antibiotic Resistance Genes ◽

Broad Host Range ◽

Human Pathogens ◽

Current Crisis ◽

Acquired Drug Resistance ◽

Resistance Plasmids

Antibiotic resistance (AR) is a threat to modern medicine, and plasmids are driving the global spread of AR by horizontal gene transfer across microbiomes and environments. Determining the mobile resistome responsible for this spread of AR among environments is essential in our efforts to attenuate the current crisis. Biosolids are a wastewater treatment plant (WWTP) byproduct used globally as fertilizer in agriculture. Here, we investigated the mobile resistome of biosolids that are used as fertilizer. This was done by capturing resistance plasmids that can transfer to human pathogens and commensal bacteria. We used a higher-throughput version of the exogenous plasmid isolation approach by mixing several ESKAPE pathogens and a commensal Escherichia coli with biosolids and screening for newly acquired resistance to about 10 antibiotics in these strains. Six unique resistance plasmids transferred to Salmonella typhimurium, Klebsiella aerogenes, and E. coli. All the plasmids were self-transferable and carried 3–6 antibiotic resistance genes (ARG) conferring resistance to 2–4 antibiotic classes. These plasmids-borne resistance genes were further embedded in genetic elements promoting intracellular recombination (i.e., transposons or class 1 integrons). The plasmids belonged to the broad-host-range plasmid (BHR) groups IncP-1 or PromA. Several of them were persistent in their new hosts when grown in the absence of antibiotics, suggesting that the newly acquired drug resistance traits would be sustained over time. This study highlights the role of BHRs in the spread of ARG between environmental bacteria and human pathogens and commensals, where they may persist. The work further emphasizes biosolids as potential vehicles of highly mobile plasmid-borne antibiotic resistance genes.

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Antibiotic Resistance Genes Occurrence in Wastewaters from Selected Pharmaceutical Facilities in Nigeria

Water ◽

10.3390/w12071897 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1897 ◽

Cited By ~ 1

Author(s):

Amarachukwu Obayiuwana ◽

Abasiofiok M. Ibekwe

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Human Health Risk ◽

Antibiotic Resistance Genes ◽

Wide Distribution ◽

Mitigation Measures ◽

Pcr Analysis ◽

Resistant Bacteria ◽

Bacterial Isolates ◽

Human Pathogens

The proliferation of antibiotic-resistant bacteria (ARB) and the prevalence of antibiotic resistance genes (ARGs) in wastewaters are well-established factors that contribute to the reduced potency of antibiotics used in healthcare worldwide. The human health risk associated with the proliferation of ARB and ARGs need to be understood in order to design mitigation measures to combat their dissemination. Using the PCR analysis of genomic DNA, the prevalence of 41 ARGs active against the commonly used six classes of antibiotics was evaluated in 60 bacterial isolates obtained from pharmaceutical wastewaters in Nigeria. The ARGs most frequently detected from the bacterial isolates in each of the antibiotic classes under study include catA1 (58.3%); sulI (31.7%); tet(E) (30%); aac(3)-IV (28.3%); ermC (20%); blaTEM, blaCTX-M, blaNDM-1 at 18.3% each; which encode for resistance to chloramphenicol, sulfonamides, tetracycline, aminoglycoside, macrolide-lincosamide-streptogramin and β-lactams and penicillins, respectively. Acinetobacter spp., accession number MH396735 expressed the highest number of ARGs of all the bacterial isolates, having at least one gene that encodes for resistance to all the classes of antibiotics in the study. This study highlights wide distribution of ARB and ARGs to the antibiotics tested in the wastewater, making pharmaceutical wastewater reservoirs of ARGs which could potentially be transferred from commensal microorganisms to human pathogens.

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The Microplastic-Antibiotic Resistance Connection

10.1007/978-3-030-78627-4_9 ◽

2021 ◽

pp. 311-322

Author(s):

Nachiket P. Marathe ◽

Michael S. Bank

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Pathogenic Bacteria ◽

Antibiotic Resistance Genes ◽

Hydrophobic Surface ◽

Background Information ◽

Future Research ◽

Human Pathogens ◽

Fish Pathogens ◽

Microbial Biofilms

AbstractMicroplastic pollution is a big and rapidly growing environmental problem. Although the direct effects of microplastic pollution are increasingly studied, the indirect effects are hardly investigated, especially in the context of spreading of disease and antibiotic resistance genes, posing an apparent hazard for human health. Microplastic particles provide a hydrophobic surface that provides substrate for attachment of microorganisms and readily supports formation of microbial biofilms. Pathogenic bacteria such as fish pathogens Aeromonas spp., Vibrio spp., and opportunistic human pathogens like Escherichia coli are present in these biofilms. Moreover, some of these pathogens are shown to be multidrug resistant. The presence of microplastics is known to enhance horizontal gene transfer in bacteria and thus, may contribute to dissemination of antibiotic resistance. Microplastics can also adsorb toxic chemicals like antibiotics and heavy metals, which are known to select for antibiotic resistance. Microplastics may, thus, serve as vectors for transport of pathogens and antibiotic resistance genes in the aquatic environment. In this book chapter, we provide background information on microplastic biofouling (“plastisphere concept”), discuss the relationship between microplastic and antibiotic resistance, and identify knowledge gaps and directions for future research.

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The gut microbiota resistome provides development of drug resistance in causative agents of human infectious diseases

Nauchno-prakticheskii zhurnal «Patogenez» ◽

10.25557/gm.2017.3.8494 ◽

2017 ◽

pp. 20-32 ◽

Cited By ~ 1

Author(s):

Е.Н. Ильина ◽

Е.И. Олехнович ◽

А.В. Павленко

Keyword(s):

Drug Resistance ◽

Antibiotic Resistance ◽

Resistance Genes ◽

Integrated Approach ◽

Modern Medicine ◽

Pathogenic Microorganisms ◽

Human Pathogens ◽

Potential Source ◽

Causative Agents ◽

Bacterial Genes

С течением времени подходы к изучению резистентности к антибиотикам трансформировались от сосредоточения на выделенных в виде чистой культуры патогенных микроорганизмах к исследованию резистентности на уровне микробных сообществ, составляющих биотопы человека и окружающей среды. По мере того, как продвигается изучение устойчивости к антибиотикам, возникает необходимость использования комплексного подхода для улучшения информирования мирового сообщества о наблюдаемых тенденциях в этой области. Все более очевидным становится то, что, хотя не все гены резистентности могут географически и филогенетически распространяться, угроза, которую они представляют, действительно серьезная и требует комплексных междисциплинарных исследований. В настоящее время резистентность к антибиотикам среди патогенов человека стала основной угрозой в современной медицине, и существует значительный интерес к определению ниши, в которых бактерии могут получить гены антибиотикорезистентности, и механизмов их передачи. В данном обзоре мы рассматриваем проблемы, возникшие на фоне широкого использования человечеством антибактериальных препаратов, в свете формирования микрофлорой кишечника резервуара генов резистентности. Over the time, studies of antibiotic resistance have transformed from focusing on pathogenic microorganisms isolated as a pure culture to analysis of resistance at the level of microbial communities that constitute human and environmental biotopes. Advancing studies of antibiotic resistance require an integrated approach to enhance availability of information about observed tendencies in this field to the global community. It becomes increasingly obvious that, even though not all resistance genes can geographically and phylogenetically spread, the threat they pose is indeed serious and requires complex interdisciplinary research. Currently, the antibiotic resistance of human pathogens has become a challenge to modern medicine, which is now focusing on determining a potential source for bacterial genes of drug resistance and mechanisms for the gene transmission. In this review, we discussed problems generated by the widespread use of antibacterial drugs in the light of forming a reservoir of resistance genes by gut microflora.

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Recent Review on Subclass B1 Metallo-β-lactamases Inhibitors: Sword for Antimicrobial Resistance

Current Drug Targets ◽

10.2174/1389450120666181217101812 ◽

2019 ◽

Vol 20 (7) ◽

pp. 756-762 ◽

Cited By ~ 2

Author(s):

Aditi Kaushik ◽

Manish Kaushik ◽

Viney Lather ◽

J.S. Dua

Keyword(s):

Antibiotic Resistance ◽

Multidrug Resistance ◽

Antimicrobial Resistance ◽

Global Health ◽

Human Health ◽

Microbial Pathogens ◽

Present Review ◽

Drug Molecules ◽

Global Threat ◽

Powerful Strategy

An emerging crisis of antibiotic resistance for microbial pathogens is alarming all the nations, posing a global threat to human health. The production of the metallo-β-lactamase enzyme is the most powerful strategy of bacteria to produce resistance. An efficient way to combat this global health threat is the development of broad/non-specific type of metallo-β-lactamase inhibitors, which can inhibit the different isoforms of the enzyme. Till date, there are no clinically active drugs against metallo- β-lactamase. The lack of efficient drug molecules against MBLs carrying bacteria requires continuous research efforts to overcome the problem of multidrug-resistance bacteria. The present review will discuss the clinically potent molecules against different variants of B1 metallo-β-lactamase.

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COVID-19 Lockdowns May Reduce Resistance Genes Diversity in the Human Microbiome and the Need for Antibiotics

International Journal of Molecular Sciences ◽

10.3390/ijms22136891 ◽

2021 ◽

Vol 22 (13) ◽

pp. 6891

Author(s):

João S. Rebelo ◽

Célia P. F. Domingues ◽

Francisco Dionisio ◽

Manuel C. Gomes ◽

Ana Botelho ◽

...

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Pathogenic Bacteria ◽

Bacterial Resistance ◽

Human Microbiome ◽

Antibiotic Resistance Genes ◽

Public Health Problem ◽

Small World ◽

Physical Contact ◽

Hygiene Measures

Recently, much attention has been paid to the COVID-19 pandemic. Yet bacterial resistance to antibiotics remains a serious and unresolved public health problem that kills hundreds of thousands of people annually, being an insidious and silent pandemic. To contain the spreading of the SARS-CoV-2 virus, populations confined and tightened hygiene measures. We performed this study with computer simulations and by using mobility data of mobile phones from Google in the region of Lisbon, Portugal, comprising 3.7 million people during two different lockdown periods, scenarios of 40 and 60% mobility reduction. In the simulations, we assumed that the network of physical contact between people is that of a small world and computed the antibiotic resistance in human microbiomes after 180 days in the simulation. Our simulations show that reducing human contacts drives a reduction in the diversity of antibiotic resistance genes in human microbiomes. Kruskal–Wallis and Dunn’s pairwise tests show very strong evidence (p < 0.000, adjusted using the Bonferroni correction) of a difference between the four confinement regimes. The proportion of variability in the ranked dependent variable accounted for by the confinement variable was η2 = 0.148, indicating a large effect of confinement on the diversity of antibiotic resistance. We have shown that confinement and hygienic measures, in addition to reducing the spread of pathogenic bacteria in a human network, also reduce resistance and the need to use antibiotics.

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Extreme genome selection towards complete antimicrobial resistance in a nosocomial strain of Stenotrophomonas maltophilia complex

10.1101/735555 ◽

2019 ◽

Author(s):

Sanjeet Kumar ◽

Kanika Bansal ◽

Prashant P. Patil ◽

Amandeep Kaur ◽

Satinder Kaur ◽

...

Keyword(s):

Drug Resistance ◽

Antibiotic Resistance ◽

Antimicrobial Resistance ◽

Resistance Genes ◽

Complete Genome Sequence ◽

Complete Genome ◽

Stenotrophomonas Maltophilia ◽

Antibiotic Resistance Genes ◽

Chromosomal Origin ◽

Extreme Drug Resistance

ABSTRACTWe report first complete genome sequence and analysis of an extreme drug resistance (XDR) nosocomial Stenotrophomonas maltophilia that is resistant to the mainstream drugs i.e. trimethoprim/sulfamethoxazole (TMP/SXT) and levofloxacin. Taxonogenomic analysis revealed it to be a novel genomospecies of the Stenotrophomonas maltophilia complex (Smc). Comprehensive genomic investigation revealed fourteen dynamic regions (DRs) exclusive to SM866, consisting of diverse antibiotic resistance genes, efflux pumps, heavy metal resistance, various transcriptional regulators etc. Further, resistome analysis of Smc clearly depicted SM866 to be an enriched strain, having diversified resistome consisting of sul1 and sul2 genes. Interestingly, SM866 does not have any plasmid but it harbors two diverse super-integrons of chromosomal origin. Apart from genes for sulfonamide resistance (sul1 and sul2), both of these integrons harbor an array of antibiotic resistance genes linked to ISCR (IS91-like elements common regions) elements. These integrons also harbor genes encoding resistance to commonly used disinfectants like quaternary ammonium compounds and heavy metals like mercury. Hence, isolation of a novel strain belonging to a novel sequence type (ST) and genomospecies with diverse array of resistance from a tertiary care unit of India indicates extent and nature of selection pressure driving XDRs in hospital settings. There is an urgent need to employ complete genome based investigation using emerging technologies for tracking emergence of XDR at the global level and designing strategies of sanitization and antibiotic regime.Impact StatementThe hospital settings in India have one of the highest usage of antimicrobials and heavy patient load. Our finding of a novel clinical isolate of S. maltophilia complex with two super-integrons harbouring array of antibiotic resistance genes along with antimicrobials resistance genes indicates the extent and the nature of selection pressures in action. Further, the presence of ISCR type of transposable elements on both integrons not only indicates its propensity to transfer resistome but also their chromosomal origin suggests possibilities for further genomic/phenotypic complexities. Such complex cassettes and strain are potential threat to global health care. Hence, there is an urgent need to employ cost-effective long read technologies to keep vigilance on novel and extreme antimicrobial resistance pathogens in populous countries. There is also need for surveillance for usage of antimicrobials for hygiene and linked/rapid co-evolution of extreme drug resistance in nosocomial pathogens. Our finding of the chromosomal encoding XDR will shed a light on the need of hour to understand the evolution of an opportunistic nosocomial pathogen belonging to S. maltophilia.RepositoriesComplete genome sequence of Stenotrophomonas maltophilia SM866: CP031058

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