scholarly journals Antibiotic resistance in surface waters from a coastal lagoon of Southern Brazil under the impact of anthropogenic activities

Author(s):  
Belize Leite ◽  
Magda Antunes de Chaves ◽  
Athos Aramis Thopor Nunes ◽  
Louise Jank ◽  
Gertrudes Corção

Wastes arising from human activities can reach water bodies and contribute significantly to the presence of antibiotic resistant bacterial populations in aquatic environments. The objective of this study was to evaluate the cultivable antibiotic resistant bacterial populations from a coastal lagoon impacted by agriculture and urbanization activities. Water samples were collected in low and peak season and characterized regarding physicochemical variables, microbiological indicators and the presence of antimicrobial residues. In order to analyze the presence of resistant bacterial populations, the samples were grown in the presence of nalidixic acid, ceftazidime, imipenem and tetracycline. Genes associated with β-lactamic resistance (blaCTX-M-like, blaGES-like, blaOXA-51, blaOXA-23-like, blaSHV-like, blaTEM-like and blaSPM-1), class I integron and efflux systems (tetA, tetB, acrA, acrB, tolC, adeA, adeB, adeR, adeS, mexB, mexD, mexF and mexY) were analyzed by conventional in vitro amplification. Although antimicrobials residues were below the detection limit, resistant bacteria and resistance determinants - blaGES, class I integron, adeS, acrA, acrB, tolC, mexB, mexF - were present at almost all points, in both seasons and for all antimicrobials assessed. The high numbers of resistant bacteria counts observed after the antibiotic treatment were positively correlated to the urbanization effects on the Lagoon. Some resistant populations were even higher in the low season samples, indicating the importance of a systematic evaluation of antibiotic resistance on water resources.

2021 ◽  
Vol 80 (3) ◽  
Author(s):  
Maria Belen Sathicq ◽  
Tomasa Sbaffi ◽  
Giulia Borgomaneiro ◽  
Andrea Di Cesare ◽  
Raffaella Sabatino

The World Health Organization considers antibiotic resistance as one of the main threats to human and other animals' health. Despite the measures used to limit the spread of antibiotic resistance, the efforts made are not enough to tackle this problem. Thus, it has become important to understand how bacteria acquire and transmit antibiotic resistant genes (ARGs), in particular in the environment, given the close connection between the latter and human and animal health, as defined by the One-Health concept. Aquatic ecosystems are often strongly impacted by anthropogenic activities, making them a source for ARGs and antibiotic resistant bacteria (ARB). Although freshwater meiofauna have been the object of active research, few studies have focused on the relationship between the spread of antibiotic resistance and these organisms. In this review, we investigated freshwater meiofauna as carriers of resistances since they play a central role in the aquatic environments and can harbor human and animal potential pathogens. We assessed if these animals could contribute to the spread of ARGs and of potentially pathogenic bacteria. Only four taxa (Rotifera, Chironomidae, Cladocera, Copepoda) were found to be the subject of studies focused on antibiotic resistance. The studies we analyzed, although with some limitations, demonstrated that ARGs and ARB can be found in these animals, and several of them showed the presence of potentially pathogenic bacteria for humans and animals within their microbiome. Thus, meiofauna can be considered a source and a reservoir, even if neglected, of ARGs and ARB for the freshwater environments. However, further studies are needed to evaluate the impact of the meiofauna on the spread and persistence of antibiotic resistance in these ecosystems.


Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 775
Author(s):  
Kezia Drane ◽  
Roger Huerlimann ◽  
Michelle Power ◽  
Anna Whelan ◽  
Ellen Ariel ◽  
...  

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.


2019 ◽  
Vol 25 (16) ◽  
pp. 1861-1865 ◽  
Author(s):  
Naira Sahakyan ◽  
Margarit Petrosyan ◽  
Armen Trchounian

Overcoming the antibiotic resistance is nowadays a challenge. There is still no clear strategy to combat this problem. Therefore, the urgent need to find new sources of antibacterial agents exists. According to some literature, substances of plant origin are able to overcome bacterial resistance against antibiotics. Alkanna species plants are among the valuable producers of these metabolites. But there is a problem of obtaining the standardized product. So, this review is focused on the discussion of the possibilities of biotechnological production of antimicrobial agents from Alkanna genus species against some microorganisms including antibiotic resistant bacterial strains.


2020 ◽  
Vol 2020 (1) ◽  
pp. 148-157 ◽  
Author(s):  
James Gurney ◽  
Léa Pradier ◽  
Joanne S Griffin ◽  
Claire Gougat-Barbera ◽  
Benjamin K Chan ◽  
...  

Abstract Background and objectives Antimicrobial resistance is a growing global concern and has spurred increasing efforts to find alternative therapeutics. Bacteriophage therapy has seen near constant use in Eastern Europe since its discovery over a century ago. One promising approach is to use phages that not only reduce bacterial pathogen loads but also select for phage resistance mechanisms that trade-off with antibiotic resistance—so called ‘phage steering’. Methodology Recent work has shown that the phage OMKO1 can interact with efflux pumps and in so doing select for both phage resistance and antibiotic sensitivity of the pathogenic bacterium Pseudomonas aeruginosa. We tested the robustness of this approach to three different antibiotics in vitro (tetracycline, erythromycin and ciprofloxacin) and one in vivo (erythromycin). Results We show that in vitro OMKO1 can reduce antibiotic resistance of P. aeruginosa (Washington PAO1) even in the presence of antibiotics, an effect still detectable after ca.70 bacterial generations in continuous culture with phage. Our in vivo experiment showed that phage both increased the survival times of wax moth larvae (Galleria mellonella) and increased bacterial sensitivity to erythromycin. This increased antibiotic sensitivity occurred both in lines with and without the antibiotic. Conclusions and implications Our study supports a trade-off between antibiotic resistance and phage sensitivity. This trade-off was maintained over co-evolutionary time scales even under combined phage and antibiotic pressure. Similarly, OMKO1 maintained this trade-off in vivo, again under dual phage/antibiotic pressure. Our findings have implications for the future clinical use of steering in phage therapies. Lay Summary: Given the rise of antibiotic-resistant bacterial infection, new approaches to treatment are urgently needed. Bacteriophages (phages) are bacterial viruses. The use of such viruses to treat infections has been in near-continuous use in several countries since the early 1900s. Recent developments have shown that these viruses are not only effective against routine infections but can also target antibiotic resistant bacteria in a novel, unexpected way. Similar to other lytic phages, these so-called ‘steering phages’ kill the majority of bacteria directly. However, steering phages also leave behind bacterial variants that resist the phages, but are now sensitive to antibiotics. Treatment combinations of these phages and antibiotics can now be used to greater effect than either one independently. We evaluated the impact of steering using phage OMKO1 and a panel of three antibiotics on Pseudomonas aeruginosa, an important pathogen in hospital settings and in people with cystic fibrosis. Our findings indicate that OMKO1, either alone or in combination with antibiotics, maintains antibiotic sensitivity both in vitro and in vivo, giving hope that phage steering will be an effective treatment option against antibiotic-resistant bacteria.


2019 ◽  
Vol 15 (3) ◽  
pp. 20180895 ◽  
Author(s):  
Lauri Mikonranta ◽  
Angus Buckling ◽  
Matti Jalasvuori ◽  
Ben Raymond

Phage therapy is attracting growing interest among clinicians as antibiotic resistance continues becoming harder to control. However, clinical trials and animal model studies on bacteriophage treatment are still scarce and results on the efficacy vary. Recent research suggests that using traditional antimicrobials in concert with phage could have desirable synergistic effects that hinder the evolution of resistance. Here, we present a novel insect gut model to study phage–antibiotic interaction in a system where antibiotic resistance initially exists in very low frequency and phage specifically targets the resistance bearing cells. We demonstrate that while phage therapy could not reduce the frequency of target bacteria in the population during positive selection by antibiotics, it alleviated the antibiotic induced blooming by lowering the overall load of resistant cells. The highly structured gut environment had pharmacokinetic effects on both phage and antibiotic dynamics compared with in vitro : antibiotics did not reduce the overall amount of bacteria, demonstrating a simple turnover of gut microbiota from non-resistant to resistant population with little cost. The results imply moderate potential for using phage as an aid to target antibiotic resistant gut infections, and question the usefulness of in vitro inferences.


2019 ◽  
Author(s):  
Josephine Hyde ◽  
Courtney Gorham ◽  
Doug E. Brackney ◽  
Blaire Steven

AbstractThe emerging and increasing prevalence of bacterial antibiotic resistance is a significant public health challenge. To begin to tackle this problem, it will be critical to not only understand the origins of this resistance but also document environmental reservoirs of antibiotic resistance. In this study we investigated the possibility that both colony and field caught mosquitoes could harbor antibiotic resistant bacteria. Specifically, we characterized the antibiotic resistant bacterial populations from colony-reared Aedes aegypti larvae and adults and two field caught mosquito species Coquillettidia perturbans and Ochlerotatus canadensis. The cultured bacterial populations were dominated by isolates belonging to the class Gammaproteobacteria. Among the antibiotic resistant populations, we found bacteria resistant to carbenicillin, kanamycin, and tetracycline, including bacteria resistant to a cocktail of all three antibiotics in combination. The antibiotic resistant bacteria were numerically rare, at most 5% of total cell counts. Isolates were characterized by 16S rRNA gene sequencing, and clustering into Operational Taxonomic Units (OTUs; 99% sequence identity). 27 antibiotic resistant OTUs were identified, although members of an OTU did not always share the same resistance profile. This suggests the clustering was either not sensitive enough to distinguish different bacteria taxa or different antibiotic resistant sub-populations exist within an OTU. Finally, the antibiotic selection opened up a niche to culture mosquito-associated fungi, and 10 fungal OTUs (28S rRNA gene sequencing) were identified. Two fungal OTUs both classified to the class Microbotryomycetes were commonly identified in the field-caught mosquitoes. Thus, in this study we demonstrate that antibiotic resistant bacteria and certain fungi are common and conserved mosquito microbiome members. These observations highlight the potential of invertebrates to serve as vehicles for the spread of antibiotic resistance throughout the environment.


2021 ◽  
Vol 20 (4A) ◽  
pp. 199-209
Author(s):  
Nguyen Kim Hanh ◽  
Nguyen Trinh Duc Hieu ◽  
Nguyen Minh Hieu ◽  
Vo Hai Thi ◽  
Pham Thi Mien ◽  
...  

To assess the impact of antibiotic use in aquaculture in Nha Trang bay, we conducted this study with the aim of assessing antibiotic resistance of opportunistic pathogenic bacteria isolated from water and sediment around shrimp/fish cages in the Nha Trang bay. 109 strains of Vibrio, Salmonella-Shigella and Aeromonas groups were isolated in the surrounding environment of farming areas in Dam Bay and Hon Mieu. Antimicrobial resistance test of these 109 strains showed that in the water environment in Dam Bay, TET (96.6%) and NIT (92.5%) were the two antibiotics with the highest rates of resistant bacteria while no bacteria were resistant to RIF. All 5 types of antibiotics had a statistically insignificant percentage of antibiotic-resistant bacteria in water samples at Hon Mieu, ranging from 33.3% to 68.9%. Also in the water environment, the rate of antibiotic-resistant bacteria in Dam Bay was not influenced by the distance to the cages (42.5–66.6%). Meanwhile, in Hon Mieu, the highest rate of resistant bacteria was observed at the distance of 200 m (100%) away from cages and the lowest rate at the distance of 100 m (20%). In the sediment environment around the cages, both the Dam Bay and Hon Mieu farming areas showed the highest rates of antibiotic-resistant bacteria against TET, NIF and RIF had the lowest rate of resistant bacteria. Among the total of 109 strains tested for antibiotic resistance, 2 strains labeled TCBS_HM200 m and SS_HM200 m were found to be resistant to all 5 tested antibiotics. These two strains were respectively identified as Vibrio harveyi and Oceanimonas sp.


2017 ◽  
Vol 61 (1) ◽  
pp. 11-21 ◽  
Author(s):  
Vijay Tripathi ◽  
Eddie Cytryn

Antibiotics are considered to be one of the major medical breakthroughs in history. Nonetheless, over the past four decades, antibiotic resistance has reached alarming levels worldwide and this trend is expected to continue to increase, leading some experts to forecast the coming of a ‘post-antibiotic’ era. Although antibiotic resistance in pathogens is traditionally linked to clinical environments, there is a rising concern that the global propagation of antibiotic resistance is also associated with environmental reservoirs that are linked to anthropogenic activities such as animal husbandry, agronomic practices and wastewater treatment. It is hypothesized that the emergence and dissemination of antibiotic-resistant bacteria (ARB) and antibiotic-resistant genes (ARGs) within and between environmental microbial communities can ultimately contribute to the acquisition of antibiotic resistance in human pathogens. Nonetheless, the scope of this phenomenon is not clear due to the complexity of microbial communities in the environment and methodological constraints that limit comprehensive in situ evaluation of microbial genomes. This review summarizes the current state of knowledge regarding antibiotic resistance in non-clinical environments, specifically focusing on the dissemination of antibiotic resistance across ecological boundaries and the contribution of this phenomenon to global antibiotic resistance.


2019 ◽  
Author(s):  
Maria Fernanda Loayza Villa ◽  
Alejandro Torres ◽  
Lixin Zhang ◽  
Gabriel Trueba

Abstract Background: The use of antimicrobials in the animal industry has increased the prevalence of antibiotic resistant bacteria and antimicrobial-resistance genes which can be transferred to human microbiota through the food chain or the environment. To reduce the influx of antibiotic-resistance to the human microbiota, restrictions on antimicrobials (in food animals) have been implemented in different countries. We investigated the impact of an antimicrobial restriction on the frequency of antimicrobial-resistant bacteria in pigs (PCI 1050) from an Ecuadorian farm. Results: No differences in antimicrobial resistant coliforms or antimicrobial resistance genes (richness and abundance) were found when we compared animals fed with or without antibiotics. Nevertheless, the absence of antimicrobials in pigs didn’t impact the productive performance of animals. Conclusion: Fitness costs of antimicrobial resistance in bacteria within intestinal microbiota of animals seems to be overestimated. Avoiding antimicrobials as prophylactics in pigs fed is not enough to control maintenance and spread of antimicrobial resistance.


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