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• Can sugarcane bagasse and coffee grounds help to detoxify sewage sludge? • Biostimulating agents increased the biodegradability of the anaerobic sludge. • This method enabled microbiological stabilization of aerobic and anaerobic sludges. • Aerobic biodegradation of sludge in soil contributed to the removal of its toxicity. Sewage sludge (SS) exhibits a relevant agronomic potential due to the high content of organic matter and nutrients. However, the presence of several toxic substances can prevent its agricultural application. This study evaluated if the incorporation of stimulating agents (coffee grounds and sugarcane bagasse) could contribute to an effective increase of the SS biodegradability in order to decrease its toxicity. The samples were prepared mixing aerobic or anaerobic sludge with soil, soil and bagasse, and soil and coffee grounds. Respirometric tests showed that stimulating agents enhanced the CO 2 production. However, in terms of biodegradation efficiency, more satisfactory results were verified for the anaerobic SS, especially when mixed with coffee grounds. The biodegradation also favored the SS sanitization, eliminating the Enterobacteria. For baseline toxicity (Microtox with Aliivibrio fischeri) and phytotoxicity (Lactuca sativa), all the initial samples showed higher effects. Nevertheless, after the biodegradation, this toxicity was significantly decreased and the best results were obtained for the mixtures containing only soil and sludge. For the AREc32 assay (NRF 2 mediated oxidative stress response), although a very weak response was observed, this effect was attenuated for the aerobic SS or completely eliminated for the anaerobic SS after the biodegradation. Thus, even though the use of biostimulation agents during the biodegradation led to an enhancement of microbial respiration, their incorporation to the samples do not seem to interfere in the decrease of the toxic potential of the studied SSs. However, the SS biodegradation in aerobiosis was crucial for toxicity reduction and to accelerate its maturity. [ABSTRACT FROM AUTHOR]

An overuse of antibiotics both in human and animal health and as growth promoters in farming practices has increased the prevalence of antibiotic resistance in bacteria. Antibiotic resistant and multi-resistant bacteria are now considered a major and increasing threat by national health agencies, making the need for novel strategies to fight bugs and super bugs a first priority. In particular, Gram-negative bacteria are responsible for a high proportion of nosocomial infections attributable for a large part to Enterobacteriaceae , such as pathogenic Escherichia coli , Klebsiella pneumoniae , and Pseudomonas aeruginosa. To cope with their highly competitive environments, bacteria have evolved various adaptive strategies, among which the production of narrow spectrum antimicrobial peptides called bacteriocins and specifically microcins in Gram-negative bacteria. They are produced as precursor peptides that further undergo proteolytic cleavage and in many cases more or less complex posttranslational modifications, which contribute to improve their stability and efficiency. Many have a high stability in the gastrointestinal tract where they can target a single pathogen whilst only slightly perturbing the gut microbiota. Several microcins and antibiotics can bind to similar bacterial receptors and use similar pathways to cross the double-membrane of Gram-negative bacteria and reach their intracellular targets, which they also can share. Consequently, bacteria may use common mechanisms of resistance against microcins and antibiotics. This review describes both unmodified and modified microcins [lasso peptides, siderophore peptides, nucleotide peptides, linear azole(in)e-containing peptides], highlighting their potential as weapons to thwart bacterial resistance in Gram-negative pathogens and discusses the possibility of cross-resistance and co-resistance occurrence between antibiotics and microcins in Gram-negative bacteria. [ABSTRACT FROM AUTHOR]

The present study evaluated the use of extracts plants to control Escherichia Coli causing bovine neonatal diarrhea. Two strains of E. coli isolated from neonatal diarrhea samples were used. After identification of the bacterium, antimicrobial susceptibility was verified in vitro, followed by the calculation of the multiple antimicrobial resistance index (IRMA). The ethanolic extracts of: Guava, Pitanga, Earl Fruit, Acerola, Soursop, Pomegranate, Neem, Jenipapo, Lychee, Tamarindo, Jambo and Cider were tested. The minimum inhibitory concentration (MIC) of the extracts was determined using the plate microdilution method, where they were tested at various concentrations. The minimum bactericidal concentration (MBC) was determined after obtaining the minimum inhibitory concentration results, and then the survival curve was calculated. Both strains tested showed higher resistance to antibiotics Ceftazidime, Amicacin, Tobramycin, Tetracycline, Amoxicillin + Clavulanate, Cefoxitin and Cefotaxime and showed multidrug resistance. Regarding MIC and MBC, the extracts that showed antibacterial action were Pitanga, Tamarindo, Pomegranate, Jambo and Jenipapo. When the survival curve was evaluated, the extracts of Pitanga, Tamarindo, Pomegranate stood out against the two studied pathogens. It was concluded that the E. coli strains tested showed multiresistance, which demonstrates the indiscriminate use of antibiotics, and that the use of extracts plant extracts was effective in the concentrations studied and could be used as alternative treatments against bovine neonatal diarrhea caused by E. coli. [ABSTRACT FROM AUTHOR]

Seafood borne enteric disease is a global public-health burden. We have targeted the seafood of hitherto unexplored Indian Gangetic delta, where consumption of seafood is rampant and its export is profuse. We have reported that raw seafood is highly contaminated with E.coli and toxigenic Vibrios [V. parahaemolyticus (tdh+, tlh+, trh+), V. alginolyticus (trh+, tlh+, toxR+), V. cholerae (ctxA+, tcp+, hlyA+)], and cooked items harbor thermotolerant and high-pressure resistant Vibrios. Detection of V. cholerae with cholera toxin producing gene(ctx) and V. parahaemolyticus containing pandemic serotype (O3:K6) in seafood is of major concern to consumers. Additionally, they were found to possess in vitro hemolytic potential (42.66% V. parahaemolyticus, 14.43% V. alginolyticus, and 34.17% V. cholerae) and multidrug resistance ability. All isolates were resistant to β-lactams and most of the cephalosporins. V. alginolyticus were specifically resistant to tetracycline (100%) and quinolones (68%). As per available literature, the present study reports for the first time that seafood borne Vibrios are more threatening with respect to their drug resistance ability rather than potable-water Vibrios of this focus, a phenomenon attributed to resistant gene transfer facilitated in chitinous environments. Seasonal study reveals an upsurge in enteropathogenic-load of seafood in winter and its free-floating progenies in summer. Systemic surveillance of seafood-borne outbreaks and improvement of food preservation techniques is strongly advocated to reduce public health risk. [ABSTRACT FROM AUTHOR]

The growth of 7 strains belonging to the order of Enterobacterales, represented by the species of Citrobacter freundii, Enterobacter cloacae, Escherichia coli, Klebsiella oxytoca, Obesumbacterium proteus, Rahnella aquatilis, Raoultella terrigena, Serratia marcescens and Shimwellia pseudoproteus, was monitored on selected cultivation media. Three types of agars - Endo, MacConkey and Chromocult Coliform agar together with two incubation temperatures of 28 and 37 °C were tested under aerobic conditions. The aim of the study was to detect such essential enterobacteria harmful to beer that cannot be proven at 37 °C, which is the temperature usually used in operational laboratories in breweries. Our results showed that most of the tested strains of enterobacteria were able to grow at 28 °C on all selected types of agar. The exception was just the representatives detection of which is problematic at 37 °C. Nevertheless, a little or no growth was always observed on just one of the tested media. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the hydrophobicity, ability to adhere to solvents and the pig epithelium and coaggregation of members of family Enterobacteriaceae and Enterococcus faecalis KGPMF 49. The bacteria used in this study were isolated from traditionally made autochthonous cheese from Southeastern Serbia (Sokobanja). The percentage of adhered bacteria was different in three solvents (chloroform, ethyl acetate and xylene). The highest percentage was detected in the presence of chloroform, and the lowest percentage was detected in the presence of xylene (chloroform < ethyl acetate < xylene). A different degree of co-aggregation of enterobacteria with E. faecalis KGPMF 49 was observed. Klebsiella ornithinolytica KGPMF 8 demonstrated the highest percentage of coaggregation with E. faecalis KGPMF49 (32.29%). Klebsiella pneumoniae KGPMF 13, K. ornithinolytica KGPMF 9 and Serratia marcescens biogp 1 KGPMF 19 were found to have the ability to adhere to the pig epithelium, whereas Escherichia coli KGPMF 22 showed no such ability. The ability to co-aggregate with other species and the ability to adhere to the pig epithelium are very important characteristics of the isolated bacteria. [ABSTRACT FROM AUTHOR]

Escherichia coli O157:H7 is an important pathogenic Bacterium that threatens human health. A convenient, sensitive and specific method for the E. coli O157:H7 detection is necessary. We developed two pairs of monoclonal antibodies through traditional hybridoma technology, one specifically against E. coli O157 antigen and the other specifically against E. coli H7 antigen. Using these two pairs of antibodies, we developed two rapid test kits to specifically detect E. coli O157 antigen and E. coli H7 antigen, respectively. The detection sensitivity for O157 positive E. coli is 1 × 103 CFU per ml and for H7 positive E. coli is 1 × 104 CFU per ml. Combining these two pairs of antibodies together, we developed a combo test strip that can specifically detect O157: H7, with a detection sensitivity of 1 × 104 CFU per ml, when two detection lines are visible to the naked eye. This is currently the only rapid detection reagent that specifically detects O157: H7 by simultaneously detecting O157 antigen and H7 antigens of E. coli. Our product has advantages of simplicity and precision, and can be a very useful on‐site inspection tool for accurate and rapid detection of E. coli O157:H7 infection. [ABSTRACT FROM AUTHOR]

Copper is a required micronutrient for bacteria and an essential cofactor for redox‐active cuproenzymes. Yet, excess copper is extremely toxic, and is exploited as a bacteriocide in medical and biotechnological applications and also by the mammalian immune system. To evade copper toxicity, bacteria not only control intracellular copper homeostasis, but they must also repair the damage caused by excess copper. In this review, we summarize the bacterial cell‐wide response to copper toxicity in Enterobacteria. Tapping into the abundant research data on two key organisms, Escherichia coli and Salmonella enterica, we show that copper resistance requires both the direct copper homeostatic response and also the indirect accessory pathways that deal with copper‐induced damage. Since patterns of copper response are conserved through the Proteobacteria, we propose a cell‐wide view of copper detoxification and copper tolerance that can be used to identify novel targets for copper‐based antibacterial therapeutics. [ABSTRACT FROM AUTHOR]

The major secondary waste product of municipal wastewater treatment plants is sewage sludge, which mainly consists of dewatered microbial biomass from the anaerobic digester. This sludge is disposed off by landfilling or incineration, but can also be used in agriculture after composting if there are no high contents of heavy metals and organic pollutants in sewage sludge. [ABSTRACT FROM AUTHOR]

Aim: Following previous research on improving the cleaning of crates used to transport broiler chickens from the farm to the abattoir, a demonstration project was undertaken to investigate improvements in crate washing on a commercial scale. Methods and Results: The soak tank of a conventional crate washing system was replaced with a high‐performance washer fitted with high‐volume, high‐pressure nozzles. The wash water could be heated, and a greatly improved filtration system ensured that the nozzles did not lose performance or become blocked. Visual cleanliness scores and microbial counts were determined for naturally contaminated crates which had been randomly assigned to different cleaning protocols. Conclusions: When a combination of mechanical energy, heat and chemicals (i.e. detergent and disinfectant) was used, the results showed significant improvements to crate cleaning. Reductions of up to 3·6 and 3·8 log10 CFU per crate base were achieved for Campylobacter and Enterobacteriaceae, respectively, along with a marked improvement in visual cleanliness. Significance and Impact of the Study: Broiler transport crates may become heavily contaminated with faeces and this may contribute to the spread of disease between farms. The results of this trial may be of use in reducing the spread of zoonotic pathogens in the poultry meat supply chain. [ABSTRACT FROM AUTHOR]

Introduction: the emergence of extended-spectrum beta-lactamase-producing Entero bacteriaceae (E-ESBLs) is currently a major public health problem in the world and, in particular, in developing countries. In Cameroon, data on E-ESBLs are rare, especially in Garoua and in the northern region of the country. The objective of this study is to document the epidemiology of E-ESBL infections in small children and to explore their associations with possible risk factors. Methods: this was a cross-sectional, descriptive study conducted from June 14 to September 30, 2018, including small children with suspected urinary tract infections (UTI) attending the outpatient pediatric departments of two health facilities in the city of Garoua. Urine samples were analyzed at the Bacteriology Laboratory of the Pasteur Center of Cameroon, Annex Garoua. Bacterial culture was carried out on Bio-Rad UriSelect® chromogenic agar and the identification was confirmed by bioMérieux API 20E. The antibiotic susceptibility was determined using the bioMérieux ATB UR gallery and the ESBL phenotype was detected by the double disk synergy method according to the CA-SFM 2013 recommendations. The data was analyzed with the R Statistical Software version 2.15.2. Results: a total of 57 urine samples were collected from children aged from one month to two years, 37 boys and 20 girls. Bacteria were detected by culture in 20 samples: Escherichia coliwas the most frequently (75%) isolated species followed by Klebsiella pneumoniae(25%). More than half of the infected samples (55%) contained E-ESBL. The presence of an ESBL was significantly associated with previous antibiotic intake up to 3 months prior current UTI (p=0.01664). The E-ESBL strains showed co-resistance to different antibiotics. Conclusion: this study reveals the important dissemination of EESBLs among small children in the community and a high rate of co-resistance to the different antibiotic families commonly used. [ABSTRACT FROM AUTHOR]

Different molecules have been tested as analog receptors due to their capacity to bind bacteria and prevent cell adhesion. By using in vitro assays, the present study characterized the aqueous and alkaline extracts from microalgae Pavlova lutheri and Pavlova gyrans and evaluated the capacity of these extracts to adhere to enterobacteria (Salmonella Typhimurium). The aqueous and alkaline extracts of both species were fractionated via freeze-thawing, giving rise to soluble and insoluble (precipitate) fractions in cold water. The obtained fractions were studied using thermogravimetric, methylation analyses, and using 1D and 2D NMR techniques. The cold-water-soluble fractions obtained from the aqueous extracts were mainly composed of highly branched (1→3),(1→6)-β-glucans, whereas the cold-water-precipitate fractions were constituted by (1→3)-β-glucans. The alkaline extract fractions showed similar compositions with a high protein content, and the presence of glycosides (sulfoquinovosylglycerol (SQG), digalactosylglycerol (DGG)), and free fatty acids. The linear (1→3)-β-glucans and the alkaline extract fractions showed an adhesion capacity toward Salmonella. The chemical composition of the active fractions suggested that the presence of three-linked β-glucose units, as well as microalgal proteins and glycosides, could be important in the adhesion process. Therefore, these microalgal species possess a high potential to serve as a source of anti-adhesive compounds. [ABSTRACT FROM AUTHOR]

Enterobacteria that commonly inhabit marine environments have a great impact on human health. In this study, enterobacteria isolated from seawater in the Upper Gulf of Thailand were identified and characterized. Seawater from nine sampling sites along the Upper Gulf of Thailand contained presumptive enterobacteria that ranged from 0.22 ± 0.44 to 17.00 ± 3.97 CFU/mL. The 101 strains belonged to seven species in which Klebsiella pneumoniae was the majority (47.5% of strains). The highest prevalence was resistant to ampicillin (76.2%) and ticarcillin (72.3%), respectively, whereas none was resistant to imipenem. Forty-five antibiotic resistance patterns were observed and 33.7% exhibited multidrug resistance, emphasizing the concern about public health. Three β-lactamase genes, including ampC, blaSHV, and blaTEM, were detected at the frequencies of 47.5%, 21.8%, and 11.9%, respectively. Six virulence genes, including csgD, uge, kfu, eaeA, magA, and LTI, were detected at the frequencies of 37.6%, 31.7%, 19.8%, 16.8%, 12.9%, and 5.9%, respectively. The condition of 4% NaCl downregulated the expression of the kfu and uge genes. The 67.3% and 63.4% of strains synthesized silver nanoparticles ranging between 3.04 ± 0.64 and 20.64 ± 0.95 μg/mL and gold nanoparticles ranging between 7.77 ± 0.45 and 57.57 ± 8.00 μg/mL, respectively.

Although Brazil is currently the world’s eighth largest egg exporter, the shift of consumers towards free-range eggs may present new sanitary challenges. This study aims to evaluate the microbiological vulnerability of eggs and environmental conditions in a farm certified for both conventional and free-range systems using two standard methods (enterobacteria counting and Salmonella spp. survey). Two high-producing farms were selected for this study, one under both conventional and free-range systems at the same place as the test farm, and another under conventional system only as a control farm. Enterobacteriaceae counts were determined for eggshells; and detection of Salmonella spp. was conducted in eggs, nest box material, feeder, and sponge samples from water dispensers, feeders, production plant, besides water samples from nipple dispensers and artesian well. The average enterobacteria count (log CFUmL-1) was 0.09 for conventional and 1.73 for free-range systems (p < 0.001). While Salmonella spp. was not detected in the conventional system but was present in one feeder and three eggshells from the free-range system. Therefore, the conventional system demonstrated better hygiene-sanitary status than the free-range one. Moreover, controlling food safety should always be considered when improving animal welfare.

Background: Edwardsiella tarda infections are frequent causes of severe outbreaks in the fish farming industry besides representing possible zoonotic risks. However, naturally occurring outbreaks that affect various species besides fishes are seldom described. Aim: To report an outbreak of acute mortality caused by E. tarda affecting multiple species that inhabited a natural pond in the state of São Paulo, Brazil. Materials and methods: Three adult tilapias, three Mallard ducks and one Snow egret were necropsied and subjected to further microbiological tests. Gross and microscopic lesions were documented. The antibiotic susceptibility and phylogenetic similarities among fish and avian strains were also determined. The E. tarda species was confirmed through MALDI-TOF, partial sodB sequencing and phylogenetic analysis. Results: Macroscopical findings between the three species included intestinal dilatation, mucosal hyperaemia and mucous to liquid contents. Common histopathology findings included acute enteritis, increased number of intraepithelial lymphocytes with bacteria adhered to the intestinal epithelium and lymphoid depletion in the spleen. E. tarda was isolated from several organs from all affected species. The phylogeny employing amplified fragment length polymorphism (AFLP) of eleven strains revealed high similarity (>90%) among the isolates regardless of the affected species or sampled organs. Ten isolates of E. tarda showed susceptibility to all tested antibiotics. Conclusions: E. tarda was identified as the cause of death of the species examined. Further studies would be necessary to determine the virulence of these strains and the possible risks regarding public health.

Contamination with enterobacteria was detectable in 89% of seafood samples from three central seafood markets in Thailand. The average numbers obtained from the same type of seafood were between 1.3 ± 0.9 and 4.5 ± 1.3 log CFU/g per sample. Eighty-one strains and 16 species were distinguished based on ERIC-PCR patterns and TP-RAPD patterns, respectively. The highest prevalence (90% of strains) was resistant to penicillin G whereas none was resistant to gentamycin. In addition, 63% exhibited multidrug resistance. The 16S rDNA sequences of a representative strain from each species exhibited 99% identity to either one of six genera including Citrobacter, Enterobacter, Klebsiella, Providencia, Serratia, and Yersinia. Three β-lactamase genes including blaTEM, ampC, and shv were detected at the frequencies of 43%, 27%, and 24%, respectively. The representative strains possessing β-lactamase genes exhibited β-lactamase activity ranging from 1.96 ± 0.88 to 11.3 ± 0.37 μmol of hydrolyzed nitrocefin/min/mg protein.

Abstract Background Citrobacter strains are opportunistic pathogens often responsible for serious enteric as well as extra-intestinal diseases, and therefore the O-antigenic scheme, still in use in diagnostic identification, should be set for proper serotyping. The structures of more than 30 different Citrobacter O-antigens (O-polysaccharide chains of the lipopolysaccharides) of 43 Citrobacter O-serogroups have been elucidated so far. However, relationships between strains in several heterogeneous serogroups still need to be clarified by immunochemical studies. These include complex serogroups O3 and O8, represented by 20 and 7 strains, respectively, which are the subject of the present work. Earlier, the O-polysaccharide structures have been determined for Citrobacter O3 strain Be35/57 (PCM 1508) and Citrobacter O8 strain Be64/57 (PCM 1536). Results Serological studies (immunoblotting) carried out on Citrobacter lipopolysaccharides from different strains ascribed to serogroups O3 and O8 showed that each of these serogroups should be divided into non-cross-reacting subgroups. Based on the results of chemical analyses and 1H and 13C NMR spectroscopy the structure of Citrobacter O-antigens from strains PCM 1504 (O6) and PCM 1573 (O2) have been established. Chemical data combined with serological analyses showed that several Citrobacter strains should be reclassified into other serogroups. Conclusions Immunochemical studies carried out on Citrobacter LPS, described in this paper, showed the expediency of reclassification of: 1) strains PCM 1504 and PCM 1573 from serogroups O6 and O2 to serogroups O3 and O8, respectively, 2) strains PCM 1503 and PCM 1505 from serogroups O3 and O8 to new serogroups O3a and O8a, respectively.

Introduction: Early and adequate treatment of bloodstream infections decreases patient morbidity and mortality. The objective is to develop a preliminary method for rapid antibiotic susceptibility testing (RAST) in enterobacteria with inducible chromosomal AmpC., Methods: RAST was performed directly on spiked blood cultures of 49 enterobacteria with inducible chromosomal AmpC. Results were read at 4, 6 and 8h of incubation. Commercial broth microdilution was considered the reference method. Disks of 10 antibiotics were evaluated., Results: The proportion of readable tests at 4h was 85%. All RAST could be read at 6 and 8h. For most antibiotics, the S or R result at 4, 6 and 8h was greater than 80% after tentative breakpoints were established and Area of Technical Uncertainty was defined., Conclusions: This preliminary method seems to be of practical use, although it should be extended to adjust the breakpoints and differentiate them by species., (Copyright © 2023 Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. Published by Elsevier España, S.L.U. All rights reserved.)

The present study evaluated anaerobic co-digestion of swine manure and swine carcasses for biogas yield and inactivation/behaviour of pathogens purpose. Biochemical Methane Production tests were performed with samples containing ratios of 3, 7.5 and 15 kgcarcass m−3manure. For pathogens inactivation experiments known amounts of model microrganisms (sensitive and resistant) were artificially inoculated in anaerobic reactors at 24°C and 37°C. The addition of carcass resulted in an increase until 119% of biogas yield compared to swine manure mono-digestion. Salmonella enterica, Escherichia coli and PCV2 were reduced >3log10 (24°C or 37°C) during 30 days. At 37°C, MS2 and PhiX-174 were reduced 3log10 and 1.8log10, respectively. At 24°C, MS2 reduced 1.5 log10 and PhiX-174 did not present any decay over 30 days. Considering the most resistant biomarkers pathogens, as bacteriophage, we recommend the swine carcasses pre-treatment, such as high temperatures, for sanitary security. [ABSTRACT FROM AUTHOR]

Background: Antimicrobial combinations have been proven as a promising approach in the confrontation with multi-drug resistant bacterial pathogens. In the present study, we identify and characterize a synergistic interaction of broad-spectrum nitroreductase-activated prodrugs 5-nitrofurans, with a secondary bile salt, sodium deoxycholate (DOC) in growth inhibition and killing of enterobacteria. Results: Using checkerboard assay, we show that combination of nitrofuran furazolidone (FZ) and DOC generates a profound synergistic effect on growth inhibition in several enterobacterial species including Escherichia coli, Salmonella enterica, Citrobacter gillenii and Klebsiella pneumoniae. The Fractional Inhibitory Concentration Index (FICI) for DOC-FZ synergy ranges from 0.125 to 0.35 that remains unchanged in an ampicillin-resistant E. coli strain containing a β-lactamase-producing plasmid. Findings from the time-kill assay further highlight the synergy with respect to bacterial killing in E. coli and Salmonella. We further characterize the mechanism of synergy in E. coli K12, showing that disruption of the tolC or acrA genes that encode components of multidrug efflux pumps causes, respectively, a complete or partial loss, of the DOC-FZ synergy. This finding indicates the key role of TolC-associated efflux pumps in the DOC-FZ synergy. Overexpression of nitric oxide-detoxifying enzyme Hmp results in a three-fold increase in FICI for DOC-FZ interaction, suggesting a role of nitric oxide in the synergy. We further demonstrate that DOC-FZ synergy is largely independent of NfsA and NfsB, the two major activation enzymes of the nitrofuran prodrugs. Conclusions: This study is to our knowledge the first report of nitrofuran-deoxycholate synergy against Gram-negative bacteria, offering potential applications in antimicrobial therapeutics. The mechanism of DOC-FZ synergy involves FZ-mediated inhibition of TolC-associated efflux pumps that normally remove DOC from bacterial cells. One possible route contributing to that effect is via FZ-mediated nitric oxide production. [ABSTRACT FROM AUTHOR]

The increasing frequency of class A KPC enzymes, class B metallo‐β‐lactamases (MBLs) and class D OXA‐48 enzymes in Enterobacteriaceae makes their early identification urgent. A simple commercial MASTDISCS combi Carba plus disc system (MAST‐Carba plus) was designed for the identification of MBLs, KPC and OXA‐48 carbapenemase genes in Enterobacteriaceae. To validate the MAST‐Carba plus, a total of 77 isolates of carbapenemase‐producing Enterobacteriaceae (CPE) and 84 isolates of noncarbapenemase‐producing Enterobacteriaceae (non‐CPE) were selected for differentiation of the genes of Enterobacteriaceae by MAST‐Carba plus. Meanwhile, the carbapenemase genes such as blaKPC, blaIMP, blaVIM, blaNDM‐1 and blaOXA‐48 were detected by PCR (polymerase chain reaction). Thus, when considered on the basis of PCR results, the sensitivity of MAST‐Carba plus detection of KPC strains is 82·3%, the specificity is 100·0%, the positive predictive value is 100·0% and the negative predictive value is 92·4%. For MBLs strains, the sensitivity is 100·0%, the specificity is 97·1%, the positive predictive value is 84·6% and the negative predictive value is 100·0%. For OXA‐48 strains, the sensitivity is 100·0%, the specificity is 99·4%, the positive predictive value is 80·0% and the negative predictive value is 100·0%. Our findings suggest that MAST‐Carba plus is a rapid and promising method for identifying the MBLs, KPC and OXA‐48 carbapenemase genes in Enterobacteriaceae, which could be exploited in basic microbiology laboratory to prevent the transmission of CPE. Significance and Impact of the Study: Not only detection of carbapenemases but also identification of their genes accurately and rapidly in Enterobacteriaceae is still a major challenge for clinical laboratories in order to prevent the transmission of carbapenemase‐producing Enterobacteriaceae (CPE). Therefore, this study aimed to evaluate the performance of a new rapid method (MASTDISCS combi Carba plus) for the identification of metallo‐β‐lactamases (MBLs), KPC and OXA‐48 carbapenemase genes in Enterobacteriaceae clinical isolates. [ABSTRACT FROM AUTHOR]

The search for antagonistically active cultures of bacilli to fungal and bacterial pathogens of sugar beet root rot was carried out. Mycelial fungi are represented by genera such as Aspergillus spp., Fusarium spp., Penicillium spp., Alternaria spp., Mucor spp. et al. The study involved 44 cultures of bacilli to 10 microscopic fungi, 5 bacteria, 5 yeasts and 5 enterobacteria. We selected 14 working bacilli for further work, which have good antagonistic properties. [ABSTRACT FROM AUTHOR]

Aim of this study was to evaluate polyphenols and major and trace elements of Cladanthus arabicus and Bubonium imbricatum, along with their in vitro antibacterial activity against six multidrug resistant Enterobacteriaceae (Escherichia coli S33/16, E. coli S34/16, Proteus mirabilis S32/16, Klebsiella pneumoniae S12/16, Enterobacter cloacae S5/16, and Salmonella sp S12/14). UV spectrophotometry, ultra-high-performance liquid chromatography coupled to mass spectrometry and inductively coupled plasma mass spectrometry were used to evaluate total polyphenol content, quali-quantitative profile of single polyphenols and inorganic elements of the extract. The antibacterial activity was investigated by standard methods. Twelve polyphenols were identified in both plants and these were more concentrated in B. imbricatum than C. arabicus extracts. High levels of minerals, essential trace elements and tolerable levels of heavy metals (Cd, As and Pb) were found. Furthermore, the extracts showed also a strong in vitro antibacterial activity, particularly versus E. coli S33/16 (MIC, 0.125 mg ml−1). [ABSTRACT FROM AUTHOR]

The T5 group bacteriophages, which infect a number of enterobacterial species and strains, are useful objects for obtaining therapeutic phage preparations with broad specificity. The present work considers the biological properties of T5-related phages responsible for their ability to infect a broad spectrum of bacterial strains in spite of a limited number of known phage receptor proteins. Ability of bacteriophages to recognize bacterial O-antigens specifically enhances their capacity for infection and increases the therapeutic potential of the T5 phages. [ABSTRACT FROM AUTHOR]

Increasing beta-lactam resistance has led to the exploration of different places, such as wastewater treatment plants (WWTPs) which have been considered to be reservoirs and sources of bacterial resistance. This work aims to determine the presence of beta-lactamase-producing-Enterobacteriaceae in different points of a WWTP in Colombia. Six samplings were carried out in 2017 in the raw influent, aeration tanks, recycled sludge and final effluent of a WWTP. The beta-lactamase-producing-Enterobacteriaceae were detected and identified using phenotypic and molecular methods. Of the 353 isolates included, 28.3% corresponded to enterobacteria. The most frequent microorganisms were Escherichia coli (83%), Citrobacter freundii (11%) and Enterobacter cloacae complex (4%). The 97% of enterobacteriaceae had at least one beta-lactamase, and the most prevalent were the bla TEM (43.8%) and bla CTX-M-1group (35.8%) which were detected specially in recycled sludge and final effluent sample points. High percentage of multidrug resistance (to beta-lactams and non-beta-lactam antibiotics) was detected in E. coli (63.2%). Additionally, the typing by PFGE and MLST showed high genotypic diversity and the presence of the successful ST131 clone, globally spread. This work highlights the strong role of E. coli as a vector for the dissemination of resistance and the beta-lactamases in aquatic environments. Image 1 • Antimicrobial resistance in Latin America is a concern and few studies in WWTP. • Determination of β-lactam-resistant enterobacteria in a WWTP in an endemic country. • A high diversity and multidrug-resistant E. coli harboring β-lactamases was found. [ABSTRACT FROM AUTHOR]

Introduction: Infections of enterobacteria producing extended-spectrum ß-lactamases place a heavy burden on health systems. Little is known in osteoarticular infections, so this work studied the prevalence of these infections in a third-level hospital. Material and methods: Prevalence study in patients of a Traumatology Service during 2016, with infection criteria provided by the CDC in Atlanta, Georgia. The VITEK® 2 AST-N272 (bioMérieux) system was used for bacterial identification at the species level and for antimicrobial susceptibility tests. Results: 7.85% (n = 86) were reported with osteoarticular infections; 22.09% (n = 19) were by enterobacteria BLEEs. An average of 77.1 days of hospitalization (SD 37.7) (46-200 days); isolation of the microorganism occurred 15 days after entry. Sixteen (84.2%) patients had osteomyelitis, three (15.8%) had a prosthetic knee or hip infection. The average number of treatment days was 60 days (21-129 days). Eighteen patients (94.7%) were discharged with resolution of their infectious picture; one patient died with infection over aggregated pneumonia due to carbapenem-resistant K. pneumoniae. Discussion: The prevalence of osteoarticular infections by enterobacteria BLEEs could not be accurately calculated, but we consider it to be within what is expected, infection control measures require higher standards and there is a lack of development programs to use antimicrobials rationally to control the emergence of these pathologies. [ABSTRACT FROM AUTHOR]

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Highlights • Removal of enrofloxacin and ceftiofur was higher than 90% in a CW fed with livestock wastewater. • Removal of enrofloxacin and ceftiofur resistance bacteria was higher than 90% for 20 one week cycles. • No significant increase of antibiotic resistance bacteria was observed in CW microcosm effluents. • CWs can be a complementary wastewater treatment when its functionality is assured. Abstract This study aimed to evaluate the potential of CWs to remove bacteria, including antibiotic resistant bacteria, and antibiotics from livestock (swine production) wastewater. Microcosms were assembled with Phragmites australis (Cav.) Trin. ex Steud and feed with wastewater spiked or not with 100 µg/L of enrofloxacin or of ceftiofur, alone or as a mixture. Wastewater (spiked or not) was treated during twenty one-week cycles. Treated wastewater was collected at weeks 1, 2, 4, 8, 14, 18 and 20 to evaluate the removal of pollutants, including nutrients, organic matter, metals and added antibiotics, and total cultivable and antibiotic resistant bacteria (enterobacteria and enterococci), which were enumerated in plate culture media. After treatment, a significant reduction in pollutants load (up to 99% depending on the parameter) was observed regardless of the presence of the veterinary antibiotics. Antibiotics were also significantly removed (removal > 90%). High removal rates were achieved for enterobacteria and enterococci bacteria during the experimental period, in the presence or absence of antibiotics (mean removals between 86 and 100%). For antibiotic resistant bacteria initially present in the influent wastewater mean removals > 90% were obtained, and no significant effect of time or of antibiotic presence was observed. This study is, to our knowledge, the first to focus on the removal of enrofloxacin and ceftiofur resistance in faecal bioindicators in CWs fed with livestock wastewater. Results confirm CWs as a green alternative to reduce the risks associated with the release of livestock effluents into the environment. [ABSTRACT FROM AUTHOR]

Aims: This study investigated the occurrence and genetic diversity of Enterobacteriaceae with extended‐spectrum β‐lactamase (ESBL)‐, AmpC‐ and carbapenemase‐mediated resistance in British beef cattle, and related risk factors. Methods and Results: Faecal samples (n = 776) were obtained from farms in England and Wales (n = 20) and Scotland (n = 20) in 2015. Isolates from selective agars were identified by MALDI ToF mass spectrometry. Selected isolates were characterized by multiplex PCR (blaCTX‐M,blaOXA,blaSHV and blaTEM genes), whole‐genome sequencing (WGS), minimum inhibitory concentrations and pulsed‐field gel electrophoresis. None of the faecal samples yielded carbapenem‐resistant Escherichia coli. Ten (25%) of the farms tested positive for ESBL‐producing CTX‐M Enterobacteriaceae, 15 (37·5%) of the farms were positive for AmpC phenotype E. coli and none were positive for carbapenem‐resistant E. coli. WGS showed a total of 30 different resistance genes associated with E. coli, Citrobacter and Serratia from ESBL agars, and colocation of resistance genes with blaCTX‐M1. Buying bulls and bringing in fattening cattle from another farm were identified as significant risk factors for positive samples harbouring CTX‐M Enterobacteriaceae or AmpC phenotype E. coli respectively. Conclusions: Beef cattle on a proportion of farms in GB carry ESBL‐producing Enterobacteriaceae. Factors, such as operating as a closed herd, may have an important role in reducing introduction and transmission of resistant Enterobacteriaceae. The results indicate management factors may play an important role in impacting ESBL prevalence. In particular, further study would be valuable to understand the impact of maintaining a closed herd on reducing the introduction of resistant Enterobacteriaceae. Significance and Impact of the Study: This is the first study showing the presence of ESBL‐producing Enterobacteriaceae in British beef cattle. [ABSTRACT FROM AUTHOR]

The aim of the present study was to characterize extended-spectrum β-lactamase (ESBLs) genes in multidrug resistant enterobacterial pathogens as well as commensal isolates from the Sudan during the period 2003 to 2007. ESBL production was determined phenotypically by the combined disc method, and was characterized genotypically by the detection of blagenes by PCR and nucleotide sequencing. Transferability was examined by conjugation with nalidixic-acid resistant E. coli K12. The results showed that a total of 106 of the 113 (94%) isolates including E. coli, Klebsiella pneumoniae, proteus spp., Enterobacter cloacae, Providencia spp. and Morganella morganii, were positive for blagenes including the prototype blaTEM. Eleven isolates (28%) of the 113 were ESBL producers encoding blaSHV genes (SHV5, SHV5a, SHV12, SHV26, SHV28 and SHV38), 90 isolates (80%) were CTX-M positive. All, but only one (CTX-M9) were CTX-M15. Only 3(2.7%) of the isolates were Amp-C producers (CMY-4 and DHA-1). Plasmid transfer of the multiple resistance patterns was achieved among all the isolates. These findings demonstrated that ESBLs were highly produced by multi-resistant enterobacterial isolates from the Sudan; among both clinical pathogens as well as stool commensals. This is the first report of ESBLs genes characterization from the Sudan. [ABSTRACT FROM AUTHOR]

Water contamination in the semi-arid section of Northeast Brazil is a current concern for the country’s researchers, since this region is considered one of the poorest in Brazil and the water in these locations is a primary vehicle for disease transmission. We collected physical and chemical data as well as water samples from four semiarid potiguar reservoirs during the dry and rainy seasons of 2013 and 2014. These samples were prepared in a laboratory at the Federal University of Rio Grande do Norte (UFRN) and their physical, chemical and microbiological characteristics were evaluated. The procedures of microbial isolation and identification followed the Standard Methods for Examinations of Water and Wastewater. Then Vitek II system (Bio-Merieux®) was used to identify the microbial specimens and we calculated the frequency of specimens’ occurrence. Altogether, 168 bacteria were isolated and identified; 97% were Gram-negative and only 3% were Gram-positive. Within the Gram negatives, 73.2% were identified as belonging to the Enterobacteriaceae family and, in general terms, the most constant genera in the water reservoirs were Vibrio and Aeromonas. Among the Enterobacteriaceae family, the species Escherichia coli, Enterobacter cloacae complex and Klebsiella pneumoniae were the most frequent. There was no statistical difference between the number or morphotype groups found in the periods, p=0.255 and p=0.237, respectively. The analyzed data indicate possible contamination of these water reservoirs by human and/or animal fecal material.

88 samples of traditional and industrial table olives were collected from various outlets in the city of Tetouan. The physical-chemical controls concerned: pH , ORP (oxydo-reducing potential) and TDE (total dry extract). The microbiological side are: total aerobic mesophilic flora ( TAMB), total coliforms (TC), Staphylococcus aureus (SA) and lactic bacteria (LB) with an identification of the most predominant enterobacteria species and their sensitivity. Also to investigate the antimicrobial activity of Olive (Olea europaea L.) .The obtained results for traditional olives far exceed food hygiene standards, especially when 29.20% of traditional samples are too loaded in TAMB and TC and 16.5% are contaminated with SA. This shows that good hygiene practices are not respected. As for industrial olives, the averages in TAMB and SA are below the thresholds set by the standards, and only 19.8% are contaminated with TC which indicates the compliance of the majority of industrial type. Black table olives are the most contaminated. The identification results of coliforms extracted from traditional olives show the predominance of Citrobacter freundii and klebsiella pneumoniae .The sensitivity test shows that 80% of Enterobacteriaceae tested were sensitive to all antibiotics.The result showed that the ethanolic extrats was active against all bacteria.

We propose the main characteristics of a new bacterium species named Nissabacter archeti strain 2134 (CSURP3445 = LT631518), isolated from pustule scalp of a 29-year-old man at hospital Archet 2, Nice, south of France.

The bacterial communities that are established during natural meat fermentation depend on the processing conditions and the type of meat substrate used. Six pork samples of variable quality (reflected in pH values) and six less conventional meats (beef, horse, hare, wild deer, wild duck, and wild boar) were naturally fermented under controlled conditions in model systems. The development of lactic acid bacteria (LAB), coagulase-negative staphylococci (CNS), and enterobacteria was followed using culture-dependent techniques and (GTG)5-PCR fingerprinting of genomic DNA from the isolates obtained. Taken together, Latilactobacillus sakei was the most abundant LAB species, although Latilactobacillus curvatus was more manifest in high-pH pork. Within staphylococci, common species were encountered (i.e., Staphylococcus equorum, Staphylococcus saprophyticus, and Staphylococcus xylosus), although some atypical ones (i.e., Staphylococcus succinus) were also recovered. Within enterobacteria, Serratia spp. prevailed in more acidic pork batches and in beef, whereas Hafnia spp. prevailed in game meat fermentations. Enterobacterial counts were particularly high in fermentations with low acidity, namely for some pork batches, hare, wild duck, and wild boar. These findings should be considered when naturally fermented meat products are manufactured, as the use of game meat or meat with high pH can give rise to safety concerns.

Domestic environment, in particular, kitchen setting is a well-established source of microbial contamination. Kitchen sponges represent an important vehicle of microbial transmission and maintenance of spoilage bacteria and pathogenic strains responsible for food borne diseases. The aim of this study was to evaluate the microbial communities of 100 ‘in-use’ kitchen sponges, improving the knowledge on their role in cross-contamination in domestic environment and transmission of ESBLproducing strains. Sponges were processed for: aerobic mesophilic bacteria (AMB), Enterobacteriaceae (EB), yeasts and molds (YM), coagulase-positive staphylococci (CPS), micrococci (MCC), anaerobic sulfite reducing bacteria (ASR), and for the detection of Listeria monocytogenes, Salmonella spp. and Yersinia enterocolitica. A total of 309 enterobacteria strains were identified and then processed for ESBL (Extended Spectrum Beta Lactamase) phenotypical expression. A high contamination level of kitchen sponges was observed (mean value AMB 8.25±1.1; EB 5.89±1.2; YM 5.57±1.1; MCC 4.82±0.1 log CFU/g). Identified enterobacteria strains revealed several opportunistic and pathogenic agents such as Enterobacter cloacae (28%), Citrobacter freundii (23.3%), Cronobacter sakazakii (14.6%) and other strains in lower percentage. Listeria monocytogenes was found in only one sponge (1%). A total of 69 (22.3%) enterobacteria resulted ESBL+, with the following prevalence: P. rettgeri (50%), L. adenocarboxilata (30%), K. pneumoniae (25%), K. oxytoca (25%), C. sakazakii (20%), E. cloacae (20.7%), C. freundii (20.1%). Results confirm the potential role of kitchen sponges as vehicle for food-borne pathogens such as, C. sakazakii for the first time, infectious agents and spoilage microorganisms. The observed high contamination level and the presence of several ESBLs opportunistic pathogens, stresses the necessity to improve a proper education of the consumers on the effective treatment to reduce their microbial loads.

Different molecules have been tested as analog receptors due to their capacity to bind bacteria and prevent cell adhesion. By using in vitro assays, the present study characterized the aqueous and alkaline extracts from microalgae Pavlova lutheri and Pavlova gyrans and evaluated the capacity of these extracts to adhere to enterobacteria (Salmonella Typhimurium). The aqueous and alkaline extracts of both species were fractionated via freeze-thawing, giving rise to soluble and insoluble (precipitate) fractions in cold water. The obtained fractions were studied using thermogravimetric, methylation analyses, and using 1D and 2D NMR techniques. The cold-water-soluble fractions obtained from the aqueous extracts were mainly composed of highly branched (1→3),(1→6)-β-glucans, whereas the cold-water-precipitate fractions were constituted by (1→3)-β-glucans. The alkaline extract fractions showed similar compositions with a high protein content, and the presence of glycosides (sulfoquinovosylglycerol (SQG), digalactosylglycerol (DGG)), and free fatty acids. The linear (1→3)-β-glucans and the alkaline extract fractions showed an adhesion capacity toward Salmonella. The chemical composition of the active fractions suggested that the presence of three-linked β-glucose units, as well as microalgal proteins and glycosides, could be important in the adhesion process. Therefore, these microalgal species possess a high potential to serve as a source of anti-adhesive compounds.

The Enterobacterales order contains 7 families with more than 40 bacterial genera which are isolated from various types of environment. The genera Shimwellia, Obesumbacterium, Rahnella, Citrobacter, Klebsiella, Raoultella, Serratia and Enterobacter are often found in the beer brewing process. The ability of these bacteria to grow and multiply in the finished beer is minimal. The bacteria occur primarily as contamination of yeast. They are harmful because these bacteria produce sensory undesirable substances (e.g. dimethylsulfide, diacetyl, acetoin) at the beginning of the main fermentation and get into the finished beer. Some species are involved in the formation of N-nitrosamines harmful for health. Here we present an overview of the basic morphological and physiological properties of these bacteria and describe their importance from the point of view of harmfulness in the beer brewing process.

Aim. Comparative evaluation of species identification of microorganisms by MALDI-TOF mass-spectrometry and automatic biochemical analyzer VITEK2 Compact30. Materials and methods. Species identification of18 400 isolates of microorganisms (staphylococci, streptococci, enterococci, enterobacteria, nonfermenting gram-negative bacteria, lactobacilli, anaerobes, yeast fungi, neisseriae), isolated from vagina of pregnant and non-pregnant women and from newborns, was carried out. Identification of the isolated microorganisms was carried out by automatic bac-teriologic analyzer VITEK2 Compact30 (BioMerieux, France) and MALDI-TOF-MS analysis method on AutoflexIII (Bruker Daltonics, Germany) mass-spectrometer. Results. Comparative identification of 2005 isolates of microorganisms was carried out. Sequencing of ribosomal RNA was used as a reference method. Authenticity of species identification my MALDI-TOF-MS analysis method was: for staphylococci (95.8%), enterococci (97.5%), enterobacteria (98.4%), nonfermenting gram-negative bacteria (93.6%), P-hemolytic staphylococci (93.8%), lactobacilli (92.8%), yeast fungi (99.9%). Conclusion. Introduction of MALDI-TOF-MS analysis technology into practical work of microbiological laboratories exceeds previously used methods of microbiological testing in terms of speed, cost and authenticity of identification of a wide spectrum of microorganisms.

Aim: The objective of this study was to investigate the antimicrobial resistance genes (ARGs) in plasmids of Enterobacteriaceae from soil, sewage, and feces of food-producing animals and humans., Methods and Results: The plasmid sequences were obtained from the NCBI database. For the identification of ARG, comprehensive antibiotic resistance database (CARD), and ResFinder were used. Gene conservation and evolution were investigated using DnaSP v.6. The transfer potential of the plasmids was evaluated using oriTfinder and a MOB-based phylogenetic tree was reconstructed using Fastree. We identified a total of 1064 ARGs in all plasmids analyzed, conferring resistance to 15 groups of antibiotics, mostly aminoglycosides, beta-lactams, and sulfonamides. The greatest number of ARGs per plasmid was found in enterobacteria from chicken feces. Plasmids from Escherichia coli carrying multiple ARGs were found in all ecosystems. Some of the most abundant genes were shared among all ecosystems, including aph(6)-Id, aph(3'')-Ib, tet(A), and sul2. A high level of sequence conservation was found among these genes, and tet(A) and sul2 are under positive selective pressure. Approximately 62% of the plasmids carrying at least one ARG were potentially transferable. Phylogenetic analysis indicated a potential co-evolution of Enterobacteriaceae plasmids in nature., Conclusion: The high abundance of Enterobacteriaceae plasmids from diverse ecosystems carrying ARGs reveals their widespread distribution and importance., (© The Author(s) 2024. Published by Oxford University Press on behalf of Applied Microbiology International.)

Antibiotic resistance in Citrobacter freundii is a public health concern. This study evaluated the closed genome of a C. freundii isolated from the stool of a hospitalized patient initially related to a Salmonella outbreak. Confirmation of the isolate was determined by whole-genome sequencing. Nanopore sequencing was performed using a MinION with a Flongle flow cell. Assembly using SPAdes and Unicycler yielded a closed genome annotated by National Center for Biotechnology Information Prokaryotic Genome Annotation Pipeline. Genomic analyses employed MLST 2.0, ResFinder4.1, PlasmidFinder2.1, and VFanalyzer. Phylogenetic comparison utilized the Center for Food Safety and Applied Nutrition (CFSAN)-single nucleotide polymorphism pipeline and Genetic Algorithm for Rapid Likelihood Inference. Antimicrobial susceptibility was tested by broth microdilution following Clinical and Laboratory Standards Institute criteria. Multi-locus sequence type in silico analysis assigned the C. freundii as sequence type 64 and the blaCMY-41 gene was detected in resistome investigation. The susceptibility to antibiotics, determined using Sensititre® plates, revealed resistance to aztreonam, colistin, cefoxitin, amoxicillin/clavulanic acid, sulfisoxazole, ampicillin, and streptomycin. The genetic relatedness of the C. freundii CFSAN077772 with publicly available C. freundii genomes revealed a close relationship to a C. freundii SRR1186659, isolated in 2009 from human stool in Tanzania. In addition, C. freundii CFSAN077772 is nested in the same cluster with C. freundii clinical strains isolated in Denmark, Mexico, Myanmar, and Canada, suggesting a successful intercontinental spread., (© The Author(s) 2024. Published by Oxford University Press on behalf of Applied Microbiology International.)

Background: Pink coloration of breast milk is uncommon and it´s associated with colonization by Serratia marcescens, which is most frequently isolated in intensive care settings. Misinterpretation of the pink coloration may lead to premature cessation of breastfeeding. The objective is to present four cases of pink discoloration., Methods: Two retrospective and two prospective cases of pink discoloration in breast milk are described, which were reported to the lead author., Results: Four healthy mother-infant pairs with documented pink discoloration are presented. S. marcescens was isolated from breast milk samples. All four infants were asymptomatic and underwent enterobacteria cultures. The mothers received outpatient antibiotic treatment, and two infants received treatment as well. Subsequent cultures yielded negative results, and the pink discoloration ceased. All mothers successfully resumed breastfeeding., Conclusions: There are very few reported cases of pink breast milk in the global literature. Colonization by S. marcescens is not an indication for discontinuation of breastfeeding., (Copyright: © 2024 Permanyer.)