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Non-metric multidimensional scaling (NMDS) based on a matrix of clonal similarity of bacterial strains, including a 95% confidence ellipse. Each point represents one bacterial isolate. A heatmap of similarities within and between the studied groups is presented. The barplot (BoxWhisker Plot) of average similarity within and between groups (whiskers denote minimum and
Source publication
Hospitals are regarded as ecological niches of antibiotic-resistant bacteria (ARB). ARB can spread outside the hospital environment via hospital wastewater (HWW). Therefore, HWW is often disinfected in local stations to minimize that risk. Chlorine-based treatment is the most popular method of HWW disinfection around the world, however, recent rese...
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Context 1
... mean clonal similarity of all isolates was determined at 0.44. Genetic similarity was compared within the examined isolate groups, separately for each season (Figure 2A) (irrespective of sampling sites), as well as for each sampling site ( Figure 2B) (irrespective of season). Mean clonal similarity was higher within groups (seasons/sites) than between groups. ...
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... mean clonal similarity of all isolates was determined at 0.44. Genetic similarity was compared within the examined isolate groups, separately for each season (Figure 2A) (irrespective of sampling sites), as well as for each sampling site ( Figure 2B) (irrespective of season). Mean clonal similarity was higher within groups (seasons/sites) than between groups. ...
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... clonal similarity was higher within groups (seasons/sites) than between groups. Season exerted a greater influence on the genetic similarity of bacterial strains than disinfection (Figure 2). Strains isolated in spring (SP, 0.59) were characterized by the greatest similarity, followed by the strains isolated in summer (SU, 0.52), winter (WI, 0.49), and autumn (AU, 0.47). ...
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... isolated from HWW before disinfection were somewhat more similar (B, 0.46) than those isolated after chlorination (A, 0.44). The mean similarity of strains isolated from HWW before and after disinfection reached 0.43 ( Figure 2). values) and the box represent the second and third quartile with the median bar inside. ...
Citations
... A high density of antibiotic residues in HWW is also the main limitation for biological wastewater treatment systems (Papajová et al. 2022). Nowadays, chlorination is one of the chemical disinfected strategies due to its broad spectrum of antibacterial activity, high effectiveness and low cost (Rolbiecki et al. 2022). However the disinfection by produce and free chlorine may affect to the beneficial microorganisms of wastewater treatment process (Watson et al. 2012;Ramírez-Coronel et al. 2023). ...
... Chlorination and ultraviolet (UV) disinfection are effective used methods to treat pathogens in wastewater. However, the resistance to chlorination or UV have been commonly detected (Rolbiecki et al. 2022). Previous studies were reported the restriction ability of microalgae on pathogens in wastewater (Christabel et al. 2019;Grossart and Simon 2007;Ribalet et al. 2008;Shaima et al. 2022). ...
Chlorella sp. is able to grow and transform inorganic and organic contaminants in wastewater to create biomass. In the present study, Chlorella sp. LH2 isolated from cocoon wastewater was able to thrive in hospital wastewater, then remove nutrients and eliminate E. coli ATCC 8739. The results indicated that optimal cultivation conditions of Chlorella sp. LH2 in hospital wastewater were pH of 8, light:dark cycle of 16:8 at 30oC. The inhibitory effect of chlorination on algae growth was accompanied with the chlorine concentration. BOD5:COD ratio of 0.77 indicated biodegradability of hospital wastewater. The untreated and treated wastewatee samples were collected to investigated the nutrient removal efficiency after 10 days. Untreated and treated results were192 ± 8.62 mg/l 23.91 ± 2.19 mg/l for BOD5; 245 ± 9.15 mg/l and 47.31 ± 5.71 mg/l for COD. The treated value met the required standards for hospital wastewater treatment. The removal efficiency total nitrogen and total phosphorus were 68.64% and 64.44% after 10 days, respectively. Elimination of E. coli ATCC 8739 after 7 days by Chlorella sp. LH2 was 88.92%. The results of this study suggest the nutrients and pathogens removal potential of Chlorella sp. LH2 in hospital wastewater for further practical applications.
Supplementary Information
The online version contains supplementary material available at 10.1186/s40643-024-00748-6.
... showed that K. pneumoniae in all LMICs tends to exhibit ESBL resistance mechanisms, CP as well as combined genotypes, and these cause a greater burden on the healthcare system, especially as there are cases where healthy people are reservoirs of enzyme-producing bacteria, but also because they are the most frequently isolated bacteria encountered in hospital settings (10,17,20). Our study aligns with these findings, as Moldova is an LMIC, and AMR, as a multidimensional process, is a significant concern for the healthcare system. ...
Introduction. Antimicrobial resistance has been declared a major public health problem. As a result of excesive antibiotic usage, it became an environmental issue. This problem is now more visible in Low-and Middle-Income Countries, where it increases the social burden. One of the newest methods to fight antimicrobial-resistant bacteria (ARB) is by using bacteriophages. Aim Identification and characterization of possible phage targets from waterland. Material and methods The strains were obtained from inpatients and identified using VITEK 2 Compact and culture. The resistance profiles were determined by disk diffusion method and interpreted according to EUCAST metodology. The presence of resistance mechanisms was checked by phenotypic testing. 31 bacterial strains were selected for research. Results K. pneumoniae, P. aeruginosa, Acinetobacter spp., S. aureus, E. coli and Enterococcus spp. were identified. The resistance profile of the isolates showed: 61,5% of K. pneumoniae isolates were PDR, and 23,1% were susceptible only to Carbapenems. E. coli strains were XDR, 71,4% of P. aeruginosa and 75% of Acinetobacter spp. were PDR bacteria. The susceptibility profile of S. aureus strains showed that 3/4 were resistant to Cephalosporins and Fluoroquinolones. Conclusions Combating the AMR phenomenon starts with knowing the pathogens present in the environment. This study is the cornerstone for further research that will ultimately lead to finding suitable phages for water treatment in Moldova, hoping they will reduce the economic and social burden and also, environmental contamination.
... A high density of antibiotic residues in HWW is also the main limitation for biological wastewater treatment systems (Papajová et al. 2022). Nowadays, chlorination is one of the chemical disinfected strategies due to its broad spectrum of antibacterial activity, high effectiveness and low cost (Rolbiecki et al. 2022). However the disinfection by produce and free chlorine may affect to the bene cial microorganisms of wastewater treatment process (Watson et ...
Chlorella sp. is able to grow and transform inorganic and organic contaminants in wastewater to create biomass. In the present study, Chlorella sp. LH2 isolated from cocoon wastewater was able to thrive in hospital wastewater, then remove nutrients and eliminate E. coli ATCC 8739. The results indicated that optimal cultivation conditions of Chlorella sp. LH2 in hospital wastewater were pH of 8, light:dark cycle of 16:8 at 30 o C. The inhibitory effect of chlorination on algae growth was accompanied with the chlorine concentration. BOD 5 :COD ratio of 0.77 indicated biodegradability of hospital wastewater. The removal efficiency of COD, BOD 5 , total nitrogen and total phosphorous were 80.53%, 87.55%, 68.64% and 64.44% after 9 days, respectively. Elimination of E. coli ATCC 8739 after 7 days by Chlorella sp. LH2 was 88.92%. The results of this study suggest the nutrients and pathogens removal potential of Chlorella sp. LH2 in hospital wastewater for further practical applications.
... Despite implementing chlorine treatment to HWW before discharge into the receiving canal with 99.2 % of gram-negative removal rate, no significant difference in the resistance rate was seen between pre-and post-treatment stages. Intriguingly, it was found that chlorine treatment of HWW in a Polish HWWTP resulted in an increase in the proportion of ESBL-producing Enterobacteriaceae in the treated wastewater (Rolbiecki et al., 2022). It aligns with previous findings that HWW hosts diverse bacterial species, including variable levels of coliform bacteria observed worldwide (Khairunnisa et al., 2022;Majumder Fig. 4. Resistance percentages of isolates from each sampling site to any of antibiotics (a), and to each antibiotic (b). ...
... On the contrary, advanced oxidation processes and hybrid treatments, such as photocatalytic disinfection and solar-driven advanced oxidation, as well as nano-and ultra-filtration or photocatalytic processes, have demonstrated a significant increase in efficiency, ranging from 1 to 5 log removal of ARB in effluent (Bairán et al., 2020;Dey et al., 2023). Numerous studies suggest that bacteria resist to chlorine compounds in WWTP disinfection processes using various mechanisms including efflux pumps, overproduction of extracellular components, capsule substances, and metabolic changes (Rolbiecki et al., 2022). In the same manner, Voigt et al. (2020) reported significant differences in the number of resistant isolates at the discharge point and downstream samples, with their levels increasing post the discharge of treated wastewater into the receiving canals. ...
Antimicrobial resistance (AMR) is an escalating issue that can render illnesses more difficult to treat if effective antibiotics become resistant. Many studies have explored antibiotic resistance in bacteria (ARB) in wastewater, comparing results with clinical data to ascertain the public health risk. However, few investigations have linked the prevalence of ARB in hospital wastewater (HWW) with these outcomes. This study aimed to bridge this gap by assessing the prevalence of ARB in HWW and its receiving waters. Among the 144 isolates examined, 24 were obtained from each of the six sites (untreated wastewater, aeration tank, sedimentation tank, effluent after disinfection, upstream canal, and downstream canal). A significant portion (87.5 %) belonged to the Enterobacteriaceae family, with Klebsiella pneumoniae as the predominant species (47.9 %). The antimicrobial sensitivity testing (AST) showed that 57.6 % of the isolates were resistant to amoxicillin/clavulanic acid (AMX), the most prevalent antibiotic used within the studied hospital. The total resistance rate before and after treatment was 27.7 % and 28.0 %, respectively, with an overall multi-drug resistance (MDR) rate of 33.3 %. The multiple antibiotic resistance index (MARI) range varied between 0.0 and 0.9. The outpatient ward's three-day mean bacterial infection cases showed a significant association (Spearman's rho = 0.98) with the MARI in the sedimentation tank. Moreover, a strong correlation (Spearman's rho = 0.88) was found between hospital effluent's MARI and the seven-day mean inpatient ward case. These findings indicate that applying wastewater-based epidemiology (WBE) to hospital wastewater could provide valuable insights into understanding ARB contamination across human domains and water cycles. Future studies, including more comprehensive collection data on symptomatic patients and asymptomatic carriers, will be crucial in fully unravelling the complexities between human health and environmental impacts related to AMR.
... Changes in the biodiversity of both allochthonous and native microorganisms provide reliable information about the quality and purity of flowing waters [3,4]. According to numerous research studies, the abundance of fecal bacteria such as Escherichia coli and Enterococcus faecalis continues to increase in rivers receiving treated wastewater in urban areas [5][6][7][8][9]. These commensal gut bacteria have been long regarded as indicators of fecal pollution in the environment [10]. ...
... Chlorine disinfection can reduce bacterial counts, but it can also contribute to the transmission of genetic determinants of antimicrobial resistance. Rolbiecki et al. [8] found that chlorine disinfection of hospital wastewater promoted the survival of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae and increased their abundance in treated wastewater. Therefore, both chlorination and the absence of disinfection can accelerate the spread of antibiotic resistance in the natural environment. ...
The aim of this study was to determine the spatial distribution of enterococci as indicators of fecal pollution in river water in forest reserves and urban areas. The biodiversity, multidrug resistance, and virulence of enterococci were monitored using conventional and molecular methods, including fluorescence in situ hybridization (FISH). Enterococcal (ENT) counts determined via the FISH method were several thousand times higher than those determined by the culture-based method. This observation points to the abundance of viable but non-culturable (VBNC) bacteria that are often more toxic. Water from the river source was characterized by the lowest number of multidrug-resistant and virulent enterococcal strains. The abundance of the analyzed bacteria was highest (more than 50% of the strains) in the area where treated wastewater was evacuated to the river. Statistical analysis confirmed the presence of relationships between these environments. Pathogenic enterococci, which are not effectively eliminated during wastewater treatment, spread in the river continuum, thus posing a health threat to humans and animals. A combination of conventional and molecular techniques for the identification of bacteria supports a rapid and reliable assessment of pollution sources in the examined environment and the implementation of protective measures.
... Moreover, current wastewater treatments have proven ineffective against certain resistant bacterial strains, and in some cases are even considered responsible for increasing their resistance. For example, a recent study showed that chlorine disinfection increased the proportion of extended-spectrum beta-lactamase (ESBL)-producing bacteria in hospital wastewater [12]. Therefore, it is necessary to explore other ways of disinfecting wastewater to control MDR pathogenic bacteria. ...
There is an increasing need to discover effective methods for treating municipal wastewater and addressing the threat of multidrug-resistant (MDR) strains of bacteria spreading into the environment and drinking water. Photodynamic inactivation (PDI) that combines a photosensitiser and light in the presence of oxygen to generate singlet oxygen and other reactive species, which in turn react with a range of biomolecules, including the oxidation of bacterial genetic material, may be a way to stop the spread of antibiotic-resistant genes. The effect of 5,10,15,20-(pyridinium-3-yl)porphyrin tetrachloride (TMPyP3) without light, and after activation with violet-blue light (VBL) (394 nm; 20 mW/cm2), on MDR strains of Pseudomonas aeruginosa, Klebsiella pneumoniae and K. pneumoniae OXA-48 in tap water and municipal wastewater was investigated. High toxicity (~2 μM) of TMPyP3 was shown in the dark on both strains of K. pneumoniae in tap water, while on P. aeruginosa toxicity in the dark was low (50 μM) and the PDI effect was significant (1.562 μM). However, in wastewater, the toxicity of TMPyP3 without photoactivation was much lower (12.5-100 μM), and the PDI effect was significant for all three bacterial strains, already after 10 min of irradiation with VBL (1.562-6.25 μM). In the same concentrations, or even lower, an anti-adhesion effect was shown, suggesting the possibility of application in biofilm control. By studying the kinetics of photoinactivation, it was found that with 1,562 μM of TMPyP3 it is possible to achieve the complete destruction of all three bacteria after 60 min of irradiation with VBL. This study confirmed the importance of studying the impact of water constituents on the properties and PDI effect of the applied photosensitiser, as well as checking the sensitivity of targeted bacteria to light of a certain wavelength, in conditions as close as possible to those in the intended application, to adjust all parameters and perfect the method.
... To the best of our knowledge, this is the first study to analyze HWW with the use of the long-read metagenomic approach. The present study was undertaken to determine changes in the HWW metagenome induced by chlorine disinfection, and it is a continuation of our preliminary research on the abundance of extended spectrum beta-lactamase-producing (ESBL) bacteria of the family Enterobacteriaceae in wastewater before and after disinfection [43]. The results of preliminary analyses involving culture-based methods suggest that ARB can survive the disinfection process and that chlorination can increase the proportion of ARB in disinfected wastewater. ...
... The research site and the sampling procedure were described in detail in our preliminary study [43]. In short, the study was conducted in a hospital that treats patients with respiratory diseases in north-eastern Poland. ...
... The percentage of ARB in HWW samples increased after disinfection, which suggests that these bacteria were more able to adapt and proliferate in disinfected wastewater. Similar observations were made in our preliminary study of the same HWW samples, which revealed an increase in the abundance of ESBL-producing Enterobacteriaceae in the population that survived the disinfection process [43]. Similar trends were reported by other authors who found that bacteria resistant to chloramphenicol, trimethoprim, and cephalothin had a higher tolerance to chlorine [46]. ...
The aim of the present study was to analyze changes in the microbiome, resistome, and mobilome of hospital wastewater (HWW) induced by disinfection with chlorine compounds. Changes in bacterial communities and specific antibiotic resistance genes (ARGs) in HWW were determined with the use of a nanopore long-read metagenomic approach. The main hosts of ARGs in HWW were identified, and the mobility of resistance mechanisms was analyzed. Special attention was paid to the prevalence of critical-priority pathogens in the HWW microbiome, which pose the greatest threat to human health. The results of this study indicate that chlorine disinfection of HWW can induce significant changes in the structure of the total bacterial population and antibiotic resistant bacteria (ARB) communities, and that it can modify the resistome and mobilome of HWW. Disinfection favored the selection of ARGs, decreased their prevalence in HWW, while increasing their diversity. The mobility of the HWW resistome increased after disinfection. Disinfection led to the emergence of new drug resistance mechanisms in previously sensitive bacterial taxa. In conclusion, this study demonstrated that HWW disinfected with low (sublethal) concentrations of free chlorine significantly contributes to the mobility and transfer of drug resistance mechanisms (including critical mechanisms) between bacteria (including pathogens).
... This is concerning because ESBL-producing bacteria are highly resistant to antibiotics and can cause serious infections in human health. Moreover, disinfection with chlorine in WWTPs has been shown to promote the survival of ESBL-producing bacteria, as reported by Rolbiecki et al. (2021b). This, coupled with the accumulation of antibiotics at the discharge of municipal wastewater, as reported in several studies (Susan et al. 2005;Metcalfe et al. 2010), raises the possibility that ESBLproducing genes could be transmitted to non-ESBL-producing bacteria in the environment. ...
Antibiotic-resistant bacteria (ARBs) can now be detected not only in clinical institutions but also in wastewater treatment plants (WWTPs), extending the range of emergence to residential areas. In this study, we investigated the change of antibiotic-resistant Escherichia coli (E. coli) and other coliforms in each treatment process at WWTPs. Throughout the treatment process, the numbers of E. coli and other coliforms were significantly reduced to less than 5.7 ± 0.5 CFU/100 ml and 2.4 ± 0.0×10² CFU/100 ml, respectively. However, ESBL-producing E. coli and other coliforms were detected in each treatment process (even after chlorination) at 5.6% and 4.8%, compared to the total E. coli and other coliforms counts. Then, ESBL-producing-related genes were identified via PCR analyses, and the most predominant gene was CTX-M-9 in both E. coli (47.2%) and other coliforms (47.3%). Although actual WWTPs greatly reduced the number of bacteria, the relative prevalence of ESBL-producing bacteria was increased, suggesting that ESBL-producing bacteria remain in the effluent at minimal concentrations and could be diffusing to water bodies.
... This corresponds to the results of carbapenem-RAC as described above and indicates that ESBL-RAC was the most tolerant bacteria to chlorine disinfectant relative to EC, and CF. Likewise, it has been reported that chlorine-based disinfection promotes the survival of ESBL-producing bacteria and/or the transmission of genetic determinants of antimicrobial resistance (Rolbiecki et al., 2022). In the case of insufficient chlorine dosage in the disinfection of a hospital wastewater discharge, it might highly possibly survived-fugitive ESPL-RAC. ...
... Similar to the case of Acinetobacter spp. described previously, the chlorination process can promote the horizontal transfer of plasmids by natural transformation (Jin et al., 2020;Rolbiecki et al., 2022). ...
In this study, a total of 200 samples, including 100 neck skin and 100 cecum samples, were collected and analyzed from various poultry slaughterhouses on different sampling days. ESBL-producing Enterobacteriaceae were isolated and ESBL production was confirmed phenotypically by combined disk diffusion and E-test gradient strips. While ESBL production was confirmed in 10 (10%) of 100 neck skin samples, no significant ESBL production could be confirmed in 100 cecal samples. The broth microdilution method of Clinical and Laboratory Standards Institute (CLSI) was used to determine the resistance profiles against benzalkonium chloride (BC), cetylpyridinium chloride (CPC), N-alkyl dimethyl benzyl ammonium chloride (ADBAC) and potassium peroxymonosulfate (PPMS) disinfectants in 10 neck skin isolates with confirmed ESBL production. In the study, it has been determined that MIC50 and MIC90 values were respectively ADBAC (8 and 16 mg/L), BC (16 and 32 mg/L), CPC (16, and 32 mg/L), PPMS (≥ 1024 mg/L). The impacts of Enterobacteriaceae strains on food safety and public health are significant; Disinfectant resistance can lead to increased transmission of antibiotic-resistant bacteria, leading to serious infections in humans that are difficult to treat. For that reason, it is of great importance to develop effective control methods, including appropriate disinfectant use, hand hygiene and appropriate isolation measures, to prevent the spread of disinfectant resistant Enterobacteriaceae strains in food production systems.
