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Providencia alcalifaciens is a Gram-negative bacterium found in various water and land environments and organisms, including insects and mammals. Some P. alcalifaciens strains encode gene homologs of virulence factors found in pathogenic Enterobacterales members, such as Salmonella enterica serovar Typhimurium and Shigella flexneri. Whether these genes are pathogenic determinants in P. alcalifaciens is not known. In this study, we investigated P. alcalifaciens-host interactions at the cellular level, focusing on the role of two type III secretion systems (T3SS) belonging to the Inv-Mxi/Spa family. T3SS1b is widespread in Providencia spp. and encoded on the chromosome. A large plasmid that is present in a subset of P. alcalifaciens strains, primarily isolated from diarrheal patients, encodes for T3SS1a. We show that P. alcalifaciens 205/92 is internalized into eukaryotic cells, lyses its internalization vacuole, and proliferates in the cytosol. This triggers caspase-4-dependent inflammasome responses in gut epithelial cells. The requirement for the T3SS1a in entry, vacuole lysis, and cytosolic proliferation is host cell type-specific, playing a more prominent role in intestinal epithelial cells than in macrophages or insect cells. In a bovine ligated intestinal loop model, P. alcalifaciens colonizes the intestinal mucosa and induces mild epithelial damage with negligible fluid accumulation in a T3SS1a- and T3SS1b-independent manner. However, T3SS1b was required for the rapid killing of Drosophila melanogaster. We propose that the acquisition of two T3SS has allowed P. alcalifaciens to diversify its host range, from a highly virulent pathogen of insects to an opportunistic gastrointestinal pathogen of animals.

Decompensated cirrhotic patients experience severely increased intestinal permeability and bacterial translocation. Thus, autologous blood salvaged during deceased donor liver transplantation (DDLT) may be contaminated with enteric bacteria. We aimed to evaluate bacterial contamination of autologous blood salvaged during DDLT and its association with post-transplant bacteremia. In 30 patients undergoing DDLT, bacterial culture was performed in salvaged autologous blood samples: one before graft reperfusion (non-leukoreduced) and two after graft reperfusion (non-leukoreduced and leukoreduced). The primary outcome was bacterial contamination of salvaged autologous blood. Seven of 30 patients (23.3%) were positive for bacteria (3 enteric/4 non-enteric) before graft reperfusion while 11 patients (36.7%) were positive (5 enteric/6 non-enteric) after graft reperfusion. Six of 7 patients who were positive for bacteria before graft reperfusion were positive after graft reperfusion with the same bacteria. Only 4 of 11 contaminated blood samples were converted to negative after leukoreduction. Post-transplant bacteremia risk was insignificantly greater in patients who received autologous blood with bacteria than in patients without bacteria (30.0% vs. 5.0%, P = 0.06). We found contamination of salvaged autologous blood with enteric bacteria throughout DDLT and incomplete performance of leukoreduction, indicating high bacterial load. The potential association between contaminated autotransfusion and post-transplant bacteremia warrants further validation in a larger prospective study. Clinical trial notation: This study was registered at the Clinical Research Information Service (CRiS; https://cris.nih.go.kr; No. KCT0007223; principal registration investigator: Sangbin Han, date of registration: April 25, 2022). [ABSTRACT FROM AUTHOR]

In this study, the affinity potentials of biosynthesized and functionalized iron oxide nanoparticles (IONPs), gold nanoparticles (AuNPs), and iron-gold nanocomposites (Fe3O4-AuNCs) harnessed to target enteric pathogens were evaluated. Colloidal IONPs and AuNPs biosynthesized by Bacillus subtilis were monitored and characterized with UV–Vis spectroscopy, Fourier transform infrared (FTIR), scanning electron microscope (SEM), energy dispersive X-ray (EDX), and X-ray diffractometer (XRD). The synthesized nanoparticles were functionalized independently and as nanocomposites with the ligand (ethylenediaminetetraacetic acid (EDTA)) and polymers (polyethyleneimine (PEI) and polyethylene glycol (PEG)). Affinity capture of the derived functionalized nanoparticles and nanocomposites was evaluated on enteric bacteria and monitored at 540–600 nm wavelengths. Colloidal suspensions of the biosynthesized IONPs and AuNPs showed UV–Vis absorption peaks at 261 and 548 nm and mean distribution sizes of 72 and 83 nm, respectively. The energy dispersive X-ray (EDX) analysis showed 48.59% zerovalent iron oxide and 51.26% zerovalent gold. X-ray diffractometer (XRD) reported Bragg's peaks corresponding with the crystal lattice of iron oxide and gold nanoparticles. Capped Fe3O4-AuNCs functionalized with PEI had a significantly higher ratio of zerovalent gold (75.56%) compared to capped Fe3O4-AuNCs functionalized with PEG (61.40%); however, an increased zerovalent iron oxide (20.00%) than PEI-functionalized Fe3O4-AuNCs (7.40%). Capped Fe3O4-AuNCs showed significant binding affinities with Bacillus cereus, Salmonella typhi, Staphylococcus aureus, and Klebsiella aerogenes. The results show that ligands and polymers could enhance Fe3O4-AuNCs' ability to interact and bind to enteric bacterial pathogen's negatively charged cell wall (teichoic acid) and outer membrane (lipopolysaccharides). Biosynthesized and functionalized IONPs, AuNPs, and Fe3O4-AuNCs provide cost-effective and feasible nano-based detection of enteric bacteria. [ABSTRACT FROM AUTHOR]

Immunoglobulin A (IgA) is notable for its broad specificity toward multiple bacteria. Phosphorylcholine (PC) plays a role in the infection of pathogenic bacteria carrying PC and in the induction of IgA responses in the host immune system. The commercially available mouse monoclonal IgA, TEPC15-IgA, is a distinctive antibody with specificity for PC, warranting further exploration of its response to PC-bearing enteric bacteria. In this study, using 17 different enteric bacteria, including 3 aerobic and 14 anerobic bacteria that could be cultured in vitro, we confirmed that TEPC15-IgA recognizes 4 bacterial species: Lactobacillus taiwanensis, Limosilactobacillus frumenti, Streptococcus infantis, and Escherichia coli, although reactivity varied. Interestingly, TEPC15-IgA did not react with four of six Lactobacillus species used. Moreover, distinct target molecules associated with PC in L. taiwanensis and L. frumenti were evident, differing in molecular weight. These findings suggest that the natural generation of PC-specific IgA could prevent PC-mediated infections and potentially facilitate the formation of a microflora rich in indigenous bacteria with PC, particularly in the gastrointestinal tract. [ABSTRACT FROM AUTHOR]

BackgroundDiarrhea is the second leading cause of morbidity and mortality worldwide among all ages, and one of the leading causes of poor health and premature death in the developing world. Microorganisms, such as viruses, bacteria, and parasites, are responsible for enteric infections among children. Excessive and inappropriate use of antimicrobial drugs and poor infection control practices have transformed antimicrobial resistance into a serious threat to public health worldwide. Therefore, it is essential to investigate the prevalence of enteric pathogens and the antimicrobial susceptibility patterns of bacterial pathogens.ObjectiveAssess the prevalence of enteric pathogens associated with diarrhea in children under 5 years at the Bule Hora Health Facility in 2021.MethodsAn institution-based cross-sectional study was conducted from May 2021 to July 2021 in a Bule Hora Health Centre and Hospital. A total of 422 children with diarrhea were included in the study in the outpatient department. Sociodemographic and associated factors were evaluated using a pre-tested questionnaire. A sufficient amount of stool specimens was collected following standard microbiological procedures. An antigen detection kit was used to diagnose rotaviruses, parasites were examined using microscopy, and bacterial identification was carried out by culture and biochemical tests. The antibiotic susceptibility test of the bacterial isolates was performed using the Kirby-Bauer disc diffusion method. The data were analyzed using SPSS version 20. The p-value less than 0.05 was declared statistically significant.ResultsThe overall prevalence of enteropathogens in children under 5 years of age was 17%, with no mixed infections detected. Of this, 7.8% of the children’s stool samples contained bacterial pathogens, 5% tested positive for rotavirus, and 4.2% contained intestinal parasites. Unprotected drinking water sources, poor carrier hand washing practices, and poor cleaning of utensils for child feeding were factors significantly associated with the prevalence of enteropathogens. Bacterial isolates have shown a high prevalence of resistance to amoxicillin.ConclusionTherefore, it is important to take steps to reduce the spread of enteric pathogens among children under 5 years practicing good hygiene, ensuring sanitation, and providing clean drinking water. We recommend performing antimicrobial susceptibility tests before prescribing treatment to children with diarrhea.

Study’s Novelty/Excerpt • This study investigates the bacterial contamination of borehole water at Presco campus, Ebonyi State University, Abakaliki, focusing on the identified bacteria's isolation, characterization, and antibiotic susceptibility. • The research is unique in its detailed analysis of the antibiotic resistance patterns of Shigella and Salmonella species, revealing significant resistance to commonly used antibiotics like Trimethoprim-Sulphamethoxazole and Tetracycline, while also identifying effective antibiotics such as Ceftriaxone and Levofloxacin. • These findings highlight the public health risks associated with contaminated borehole water and emphasize the need for regular monitoring and appropriate water treatment measures to ensure safe drinking water for the community. Full Abstract Water is essential for life. An adequate, safe, and accessible water supply must be available to all. Hence, this research aimed to isolate and characterize bacteria from borehole water samples located at the Presco campus, Ebonyi State University, Abakaliki, and test the antibiotic susceptibility patterns of the bacteria isolated. Twelve (12) water samples were collected from six (6) locations in duplicates and analyzed using standard microbiological methods. Serial dilutions were performed on the samples and dilutions of 103 were plated using the pour plate method. After the incubation periods, colonies were counted and expressed in CFU/mL, biochemical tests were carried out and the antibiotics susceptibility profiles of the bacteria isolated were evaluated. From the results, the total microbial counts ranged from 1.0 x 104 to 5.9 x 104 CFU/mL, indicating high contamination of the water samples. The morphology and biochemical tests revealed the presence of Shigella species 5 (45.4 %) and Salmonella species 6 (54.6 %). Shigella species were highly resistant to both Trimethoprim-Sulphamethoxazole and Amoxicillin (80 %) and to Tetracycline (100 %) but were susceptible to Ceftriaxone (100 %) and Ciprofloxacin (80 %). On the other hand, Salmonella species showed a resistant pattern of 83.3 % to Tetracycline, Ciprofloxacin, and Ceftriaxone but were susceptible to Levofloxacin (100 %) and Cefepime (83.3 %). This result is of public health importance as these organisms can threaten individuals utilizing these boreholes as the source of drinking water.

India is a major contributor to the global dairy industry. Hence, the evaluation of buffalo milk quality is a matter of paramount importance. Multistage cluster sampling methods were implemented in collecting buffalo milk samples from rural areas of South Gujarat. Buffalo milk was collected from villages in Navsari, Surat, Valsad, Bardoli, Vyara and Vapi. The collection of the milk was done in sterilised bottles. A total of 51 samples were collected from the villages at various times of day. Serial dilution was done, and the pour plate method was used to plate the bacteria on nutrient agar. Enteric bacterial isolates were characterised using molecular tools involving DNA extraction, 16S rRNA gene amplification (PCR), gel electrophoresis, and sequencing. MEGA 7 software that uses 16S rRNA genes to produce phylogenetic trees was also applied. The isolated and identified bacteria were Providencia vermicola, Proteus cibarius, Enterobacter cloacae strain 1, Enterobacter cloacae strain 2, and Atlantibacter hermannii. Most of these enteric bacteria isolated are opportunistic pathogens. It is recommended that the practice of consuming raw milk should be discouraged through education. Active sanitation in buffalo farms is also recommended. [ABSTRACT FROM AUTHOR]

Two-component systems are ubiquitous signaling mechanisms in bacteria that enable intracellular changes from extracellular cues. These bacterial regulatory systems couple external stimuli to control genetic expression via an autophosphorylation cascade that transduces membrane signals to intracellular locations, thereby allowing bacteria to rapidly adapt to the changing environmental conditions. Well known to control basic cellular processes, it is evident that two-component systems also exercise control over virulence traits, such as motility, secretion systems, and stress responses that impact the complex cascade of networks that alter virulence traits. In the gastrointestinal system, cues for activation of virulence-related two-component systems include metal ions, host-derived metabolites, and gut conditions. The diversity and origin of these cues suggest that the host can exert control over enteric pathogenicity via regulation in the gastrointestinal system. With the rise in multi-drug resistant pathogens, the potential control of pathogenicity with host cues via two-component systems presents a potential alternative to antimicrobials. Though the signaling mechanism itself is well studied, to date there is no systematic review compiling the host-associated cues of two-component systems and virulence traits. This review highlights the direct link between the host gastrointestinal environment and pathogenicity by focusing on two-component systems that are associated with the genetic expression of virulence traits, and that are activated by host-derived cues. The direct link between the host gastrointestinal environment, metabolites, and pathogenicity established in this review both underscores the importance of host-derived cues on bacterial activity and presents an enticing therapeutic target in the fight against antimicrobial resistant pathogens.

Abstract The significance of water in public health cannot be overemphasized. In Nigeria, many people living along the courses of water bodies still source and drink from the rivers and streams. There is, therefore, the need to determine the load of contamination and effect of pH and salinity on the decay rate of enteric bacteria in water samples from River Owena, Owena, Nigeria, in order to develop adequate water quality management. Water samples from River Owena were collected from three sampling points (inflow, middle course and the outflow) along the River Owena, Nigeria. The load of enteric bacteria in the water samples was enumerated using membrane filtration technique. The physicochemical parameters of the water samples were determined using standard methods. The incidence and prevalence of gastroenteritis in the community around River Owena was determined using a structured questionnaire. Microcosm studies were used to determine the decay rate of enteric bacteria at varying salinity and pH. Canonical correlation analysis was used to describe the relationship between the load of enteric bacteria and the incidence and prevalence of gastroenteritis in the community around River Owena. The incidence and prevalence of gastroenteritis in the community around River Owena were estimated to be 0.75 and 0.51, respectively. Escherichia coli had positive relationships with incidence (r = 0.76) and prevalence (r = 0.65). Similarly, faecal coliforms had positive relationships with incidence (r = 0.82) and prevalence of gastroenteritis (r = 0.67), while enterococci showed positive relationship with incidence (r = 0.59) and prevalence of gastroenteritis (r = 0.87). Increase in pH and salinity increased the decay rate of enteric bacteria thereby reducing the growth of enteric bacteria, the optimum pH for the growth and survival of enteric bacteria ranged between pH 5.0 and pH 7.0. The optimum salinity for the growth of enteric bacteria isolated in water samples from River Owena ranged between 10 and 50% salinity. Findings revealed high levels of faecal contamination at the different representative monitoring points on River Owena, pH and salinity influenced the load and decay rate of enteric bacteria in water from River Owena.

Nothing can replace water as the most vital natural resource we utilize on a daily basis. It is the most critical component of the earth's life support system, and life would not be possible without it. The world's population is growing at an alarming rate, making freshwater availability a significant problem for emerging nations like India. The environment is becoming out of balance due to pollution from point and non-point sources. To be fit for human consumption, water must be clear of all pollutants. High dangers to human health are increased by contaminated water systems. Gomati Taal, Madho, Tanda, Pilibhit, Uttar Pradesh is the source of the Gomti River (25°30'N; 83°10' E). A bacterial evaluation of the Gomti River's several Ghats has been conducted in light of the pollution levels and how they affect human health. It has been explored how the existence of indicator bacteria affects other microorganisms. [ABSTRACT FROM AUTHOR]

ABSTRACTSexual transmission of enteric pathogens among men who have sex with men (MSM) is well documented, although whether providers are cognizant of this risk when MSM patients present with gastrointestinal symptoms has not been studied. Over 34 months at a major tertiary metropolitan medical system, this study retrospectively analyzed 436 BioFire FilmArray Gastrointestinal results from 361 patients documented as MSM. An extensive chart review was performed, including specific sexual behaviors, socioeconomic risk factors, and whether providers charted a sexual history when a patient presented for care. Overall BioFire positivity rate was 62% with no significant difference in positivity between persons living with HIV and those without. Patients charted as sexually active had a significantly increased odds ratio (OR) of a positive result compared to those who were not. Anilingus had the highest OR. Providers charted any type of sexual history in 40.6% of cases, and HIV/infectious disease providers were significantly more likely to do this compared to other subspecialties. Sexual transmission of enteric pathogens within MSM is ongoing, and patients are at risk regardless of living with HIV. Not all sexual behaviors have the same associated risk, highlighting opportunities to decrease transmission. Increased provider vigilance and better patient education on sexual transmission of enteric pathogens are needed to reduce the disease burden.IMPORTANCEOur work adds several key findings to the growing body of literature describing the epidemiology of enteric pathogens as sexually transmitted infections among men who have sex with men (MSM). We analyzed clinical test results, housing status, provider awareness, sexual behaviors, and symptoms for 361 patients. We found that any sexual activity was associated with an increased risk of diarrheal pathogen detection, whereas being unhoused was not a risk factor. These findings suggest separate transmission networks between unhoused persons, who are also at risk of infectious diarrhea, and MSM. Moreover, our study suggested low awareness among patient-facing clinicians that diarrheal pathogens can be sexually transmitted. Together, our findings indicate an important opportunity to disrupt transmission cycles by educating clinicians on how to assess and counsel MSM patients.

This study set out to determine the sanitary risk scores and microbial health risks associated with wells and boreholes in Ilara-Mokin and Ibule-Soro, Nigeria. Water samples (n = 96) were collected over a period of five months to determine the levels of enteric bacteria and to perform a Quantitative Microbial Risk Assessment (QMRA) of drinking water quality. Sanitary risk scores revealed `medium' and `low' overall risks for the wells and boreholes, respectively. Three risk factors (faulty fence; small apron; pollution sources) exhibited high significant (p < 0.01) association with the presence of E. coli and thermotolerant coliforms in water samples from the wells. E. coli and Salmonella ranged from 1.82 to 2.28 and 2.15 to 2.63 log10 CFU/100 ml respectively in water from the wells, but were below detection limit in water from the boreholes. Shigella and Campylobacter were detected in all water samples. Estimated risks of infection associated with Shigella (2.1 × 10−2 to 2.3 × 10−1) were higher than those of Campylobacter (6.7 × 10−2 to 1.9 × 10−1) and Salmonella (1.9×10−3 to 5.6×10−3). Adaption of water safety plans may be advantageous in these settings, since intentional ingestion of water from the wells and boreholes may pose potential risks of diarrheal illness to humans. HIGHLIGHTS Sanitary risks and water samples were collected from wells and boreholes.; Microbial risk assessment was used to evaluate human dose-response data.; Sanitary risk scores correlated positively with microbial water quality.; Risk factors exhibited significant association with the presence of E. coli.; Estimated risks of infection associated with Shigella were higher than those of Campylobacter and Salmonella.;

Identification of enteric bacteria species by whole genome sequence (WGS) analysis requires a rapid and an easily standardized approach. We leveraged the principles of average nucleotide identity using MUMmer (ANIm) software, which calculates the percent bases aligned between two bacterial genomes and their corresponding ANI values, to set threshold values for determining species consistent with the conventional identification methods of known species. The performance of species identification was evaluated using two datasets: the Reference Genome Dataset v2 (RGDv2), consisting of 43 enteric genome assemblies representing 32 species, and the Test Genome Dataset (TGDv1), comprising 454 genome assemblies which is designed to represent all species needed to query for identification, as well as rare and closely related species. The RGDv2 contains six Campylobacter spp., three Escherichia/Shigella spp., one Grimontia hollisae, six Listeria spp., one Photobacterium damselae, two Salmonella spp., and thirteen Vibrio spp., while the TGDv1 contains 454 enteric bacterial genomes representing 42 different species. The analysis showed that, when a standard minimum of 70% genome bases alignment existed, the ANI threshold values determined for these species were ≥95 for Escherichia/Shigella and Vibrio species, ≥93% for Salmonella species, and ≥92% for Campylobacter and Listeria species. Using these metrics, the RGDv2 accurately classified all validation strains in TGDv1 at the species level, which is consistent with the classification based on previous gold standard methods. [ABSTRACT FROM AUTHOR]

This study set out to determine the sanitary risk scores and microbial health risks associated with wells and boreholes in Ilara-Mokin and Ibule-Soro, Nigeria. Water samples (n = 96) were collected over a period of five months to determine the levels of enteric bacteria and to perform a Quantitative Microbial Risk Assessment (QMRA) of drinking water quality. Sanitary risk scores revealed 'medium' and 'low' overall risks for the wells and boreholes, respectively. Three risk factors (faulty fence; small apron; pollution sources) exhibited high significant (p, 0.01) association with the presence of E. coli and thermotolerant coliforms in water samples from the wells. E. coli and Salmonella ranged from 1.82 to 2.28 and 2.15 to 2.63 log10 CFU/100 ml respectively in water from the wells, but were below detection limit in water from the boreholes. Shigella and Campylobacter were detected in all water samples. Estimated risks of infection associated with Shigella (2.1 x 10-2 to 2.3 x 10-1) were higher than those of Campylobacter (6.7 x 10-2 to 1.9x10-1) and Salmonella (1.9x10-3 to 5.6x10-3). Adaption of water safety plans may be advantageous in these settings, since intentional ingestion of water from the wells and boreholes may pose potential risks of diarrheal illness to humans. [ABSTRACT FROM AUTHOR]

Multidrug-resistant (MDR) bacteria are a significant contributor to the global antibiotic resistance crisis, which is predicted to kill more people than cancer by 2050. Livestock production is a contributing factor as it has been one of the fastest-growing industries in the previous century but has the most harmful effects on the environment and human health. The pig is the most widely raised and consumed food-producing animal globally, with an upward trend. The derived residues and the meat products constitute an important reservoir of antibiotic resistance genes (ARGs) that can be transmitted to humans through consumption, direct contact, the environment, or poor handling, leading to relevant zoonotic diseases, especially enteric ones. It is essential to know the diversity, abundance, and distribution of ARGs to have better control and monitoring of their dispersion. In the present study, the ARGs and Mobile Genetic Elements (MGEs) of five enteric and pathogenic species commonly present in the microbiota of both pigs and humans were examined by bioinformatic analysis. This analysis showed that 157 ARGs were distributed across 1869 genomes of five bacterial species, ranked from highest to lowest diversity of ARGs: Klebsiella pneumoniae, Escherichia coli, Enterococcus faecium, Salmonella enterica, and Enterococcus faecalis. This study contributes to better management of antibiotics, which directly impact the health of both humans and animals.

With poultry being the most abundant domestic animals worldwide, poultry farms have emerged as a prospective and widely distributed business industry in Nigeria. The outbreak of several deadly diseases that cause economic loss and discourage poultry keeping is a major challenge to poultry farming. The main goal of this study is to isolate and identify different enteric bacteria and to find the antimicrobial sensitivity profile against the pathogens isolated from specific poultry farms in Kano State. A total of 50 samples, including both poultry feed and droppings, were collected from five different poultry farms for analysis to detect the presence of enteric bacteria. The results revealed that all bacterial isolates displayed varying levels of resistance to the tested antibiotics, but they were completely susceptible to Sulfamethoxazole and Cephalexin. In general, the results of this study indicate that these samples serve as sources of E. coli, Salmonella spp., Shigella spp., and Proteus mirabilis in poultry. These pathogenic bacteria pose a health threat, potentially leading to food poisoning and infections in both animals and humans. Consequently, efficient control measures such as proper management and handling of poultry birds, and sensitization of farmers on the abuse of antibiotics are crucial to prevent cross-contamination within poultry houses and ensure the provision of high quality poultry products.

Identification of enteric bacteria species by whole genome sequence (WGS) analysis requires a rapid and an easily standardized approach. We leveraged the principles of average nucleotide identity using MUMmer (ANIm) software, which calculates the percent bases aligned between two bacterial genomes and their corresponding ANI values, to set threshold values for determining species consistent with the conventional identification methods of known species. The performance of species identification was evaluated using two datasets: the Reference Genome Dataset v2 (RGDv2), consisting of 43 enteric genome assemblies representing 32 species, and the Test Genome Dataset (TGDv1), comprising 454 genome assemblies which is designed to represent all species needed to query for identification, as well as rare and closely related species. The RGDv2 contains six Campylobacter spp., three Escherichia/Shigella spp., one Grimontia hollisae, six Listeria spp., one Photobacterium damselae, two Salmonella spp., and thirteen Vibrio spp., while the TGDv1 contains 454 enteric bacterial genomes representing 42 different species. The analysis showed that, when a standard minimum of 70% genome bases alignment existed, the ANI threshold values determined for these species were ≥95 for Escherichia/Shigella and Vibrio species, ≥93% for Salmonella species, and ≥92% for Campylobacter and Listeria species. Using these metrics, the RGDv2 accurately classified all validation strains in TGDv1 at the species level, which is consistent with the classification based on previous gold standard methods.

Diarrheagenic Escherichia coli, Campylobacter, Nontyphoidal Salmonella, and Shigella are common cause of childhood diarrhea in countries like Ethiopia, but data on their sources and coinfection profiles is limited. A cross sectional study was conducted from November 2021 to January 2023 to determine the prevalence, coinfection, and monthly occurrence rates of major diarrheagenic bacteria in diarrheic under five children and asymptomatic contacts at urban and rural settings in Ethiopia. A total of 345 stool samples were collected from; 262 diarrheic children visiting Hiwot Fana Hospital, Kersa, and Adelle Health Centers; and 83 caretakers and siblings through case based contact tracing. Samples were analyzed using standard laboratory procedures and the overall prevalence of enteric pathogens was 26.96%, with the highest isolation rate during the winter and peaks of 73.91% in February. The occurrence of the pathogens in children and tracked contacts was 27.86 and 24.09%, respectively. In our study, 8.53% coinfection and 23.66% single pathogen infection was recorded in diarrheic children. The study also showed 4.51 and 3.88% of diarrhea in children from urban and rural had attributed to bacterial coinfection, respectively. The most prevalent pathogen in diarrheic children was Diarrheagenic E. coli (10.31%), and followed by Campylobacter. On the other hand, Diarrheagenic E. coli was the second dominant bacteria following Shigella in the traced contacts, with prevalence of 8.43% and 9.64%, respectively. Based on the study site, the prevalence of Diarrheagenic E. coli and Nontyphoidal Salmonella was higher in children from urban than those from rural. However, the occurrence of each pathogen had no significant differences (P >.05) between settings. The high pathogens occurrence rate in the current study indicates the need for strong control strategies and better child carrying and treatment of diarrheal diseases at both urban and rural settings. Further studies on possible sources and factors attributing to the occurrence of enteric pathogens in children are also recommended. [ABSTRACT FROM AUTHOR]

ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) and enteric bacteria Shigella dysenteriae, Salmonella typhimurium and Escherichia Coli have been causing increasing nosocomial infections worldwide, contributing to high mortality and morbidity in surgical wards. This study attempts to investigate the feasibility of dieletrophoresis (DEP) electrode in detecting both ESKAPE and enteric bacteria in water samples. The detection is based on the bacteria's response to the non-uniform electric field in micro tapered DEP electrode and microfluidic chamber. Responses of each bacterium were recorded by varying the frequency of sinusoidal 6 voltage (peak to peak) from 10 to 13,000 kHz. Utilising the unique electrokinetic responses of each bacterium, the performance of DEP application is assessed in detecting the ESKAPE and enteric bacteria from samples within the urban water cycle, i.e., wastewater, river, runoff, and treated water from an urbanised developed area. The positive (P DEP) , negative (N DEP) and transitional, (denote as the crossover frequency f x 0) responses for each bacterium were consistently determined, spanning between 52.3 and 12,000 kHz. DEP technique was successfully able to detect ESKAPE and enteric bacteria from water samples, where water from the river proved to be the most microbially contaminated in urban water cycle. [ABSTRACT FROM AUTHOR]

Seal populations in Canadian waters provide sustenance to coastal communities. There is potential for pathogenic and/or antimicrobial‐resistant bacteria to transfer to humans through inadvertent faecal contamination of seal products. The objective of this study was to investigate the occurrence and potential antimicrobial resistance of Salmonella spp., Escherichia coli and Listeria monocytogenes in faecal samples collected from grey seals (Halichoerus grypus) in the Gulf of St. Lawrence and from ringed seals (Pusa hispida) in Frobisher Bay and Eclipse Sound, Nunavut, Canada. Grey seals were harvested during commercial hunts or during scientific sampling; ringed seals were collected by Inuit hunters during subsistence harvests. Virulence genes defining pathogenic E. coli were identified by PCR, and antimicrobial susceptibility testing was performed on recovered isolates. In grey seals, E. coli was detected in 34/44 (77%) samples, and pathogenic E. coli (extraintestinal E. coli [ExPEC], enteropathogenic E. coli [EPEC] or ExPEC/EPEC) was detected in 13/44 (29%) samples. Non‐susceptibility to beta‐lactams and quinolones was observed in isolates from 18 grey seals. In ringed seals from Frobisher Bay, E. coli was detected in 4/45 (9%) samples; neither virulence genes nor antimicrobial resistance was detected in these isolates. In ringed seals from Eclipse Sound, E. coli was detected in 8/50 (16%) samples and pathogenic E. coli (ExPEC and ExPEC/EPEC) in 5/50 (10%) samples. One seal from Eclipse Sound had an E. coli isolate resistant to beta‐lactams. A monophasic Salmonella Typhimurium was recovered from 8/50 (16%) seals from Eclipse Sound. All Salmonella isolates were resistant to ampicillin, streptomycin, sulfisoxazole and tetracycline. L. monocytogenes was not detected in any sample. These findings suggest that seals may act as important sentinel species and as reservoirs or vectors for antimicrobial‐resistant and virulent E. coli and Salmonella species. Further characterization of these isolates would provide additional insights into the source and spread of antimicrobial resistance and virulence genes in these populations of free‐living seals. [ABSTRACT FROM AUTHOR]

Various pathogenic microorganisms have been implicated as the cause of infectious diarrhea in children as a result of water and food contamination. The study's goal is to determine the reliability of complete blood count (CBC) in peripheral blood of children with acute diarrhea which infected by certain enteric bacteria, with an emphasis on leukocytes (WBCs). A study conducted to examine the pattern of bacterial distribution in children with acute diarrhea's stool, as well as the relationship between the presence of pathogenic bacteria in stool samples and the number of total WBCs and differential leukocyte count in peripheral blood. Samples size includes (76) of health none diarrhea and (174) diarrheal patients, statistical analysis revealed that co-infection by E. coli and Klebsiella sp. was significantly higher (P<0.001) among children which suffered by diarrhea in compare to health individuals. In addition, the logistic regression shows co-infections and infections by Klebsiella sp. (OR: 29.44, 16.288 respectively) more likelihood leads to acute diarrhea compare to E. coli infection alone (P<0.001). Neutrophils/Lymphocyte ratio (NRL) was (2.412) times higher and neutrophils (1.069) times more in diarrheal group (P<0.001), also the AUC for NRL was 0.833(sensitivity: 81.61 and specificity: 68.42), while for percent of neutrophils was less 0.671 (sensitivity: 46.24 and specificity: 85.71). Concluded that peripheral leukocyte count, particularly the NRL index, is helpful in children with acute diarrhea and additionally that the prevalence of diarrhea is altered by different bacterial infections. [ABSTRACT FROM AUTHOR]

The present study investigated the antibacterial activity of carvacrol against Vancomycin-Resistant Enterococci (VRE), Carbapenem-Resistant Enterobacteriaceae (CRE), Methicillin-Resistant Staphylococcus aureus (MRSA), Escherichia coli ATCC 8739, Enterococcus faecalis ATCC 29212, Streptococcus mitis, Streptococcus mutans CNCTC 8/77 and Streptococcus salivarius CNCTC 64/59. According to the results of the disc diffusion method, carvacrol has extremely high antibacterial activity with zones of 28 mm, 38 mm, 39 mm, 36 mm, 50 mm, 41 mm, 47 mm, and 39 mm against E. coli, E. faecalis, VRE, CRE, S. salivarius, S. mutans, MRSA, S. mitis, respectively. In the present study, the Minimum Inhibition Concentration (MIC) was also investigated by using the Broth Microdilution method. Carvacrol has MIC of 7.62 mg/mL against E. coli, 15.25 mg/mL against VRE, 30.5 mg/mL against E. faecalis, CRE, and S. salivarius, 61 mg/mL against S. mutans, 1.90 mg/mL against MRSA and S. mitis. Carvacrol is a very strong antimicrobial agent and may be used in important applications in the food and pharmaceutical industry. It may also be a good candidate for developing alternative treatments. The results of the present study may be beneficial for further studies with this antibacterial agent for both academia and industry. [ABSTRACT FROM AUTHOR]

Two-component systems are ubiquitous signaling mechanisms in bacteria that enable intracellular changes from extracellular cues. These bacterial regulatory systems couple external stimuli to control genetic expression via an autophosphorylation cascade that transduces membrane signals to intracellular locations, thereby allowing bacteria to rapidly adapt to the changing environmental conditions. Well known to control basic cellular processes, it is evident that two-component systems also exercise control over virulence traits, such as motility, secretion systems, and stress responses that impact the complex cascade of networks that alter virulence traits. In the gastrointestinal system, cues for activation of virulence-related two-component systems include metal ions, host-derived metabolites, and gut conditions. The diversity and origin of these cues suggest that the host can exert control over enteric pathogenicity via regulation in the gastrointestinal system. With the rise in multi-drug resistant pathogens, the potential control of pathogenicity with host cues via two-component systems presents a potential alternative to antimicrobials. Though the signaling mechanism itself is well studied, to date there is no systematic review compiling the host-associated cues of two-component systems and virulence traits. This review highlights the direct link between the host gastrointestinal environment and pathogenicity by focusing on two-component systems that are associated with the genetic expression of virulence traits, and that are activated by host-derived cues. The direct link between the host gastrointestinal environment, metabolites, and pathogenicity established in this review both underscores the importance of host-derived cues on bacterial activity and presents an enticing therapeutic target in the fight against antimicrobial resistant pathogens.

Models that can predict the level of faecal pollution in rivers are of great significance in low-and middle-income countries where residents rely on them for anthropogenic activities. Water samples from River Ala were collected from seven representative monitoring points and the load of enteric bacteria were determined. The physicochemical characteristics were determined, linear regression models and risk maps for the representative monitoring points on River Ala were developed. The concentration of Escherichia coli in the water samples from River Ala ranged from 4.87 to 5.41 log10 CFU 100 ml−1 and faecal coliforms 5.23 to 5.42 log10 CFU 100 ml−1. Temperature ranged from 26.75 to 27.50 °C and turbidity 25.10 to 36.86 NTU. E. coli had positive relationships with turbidity (r = 0.62) and rainfall (r = 0.73). Faecal coliforms had positive relationships with turbidity (r = 0.76) and rainfall (r = 0.72). Regression models produced for rainfall as a function of E. coli had R² value of 0.667; and rainfall as a function of faecal coliforms had R² value of 0.683. The developed models demonstrated high predictive values and application to other monitoring points on the course of River Ala and can be adopted in water safety plans and water management practices. HIGHLIGHTS High levels of faecal contamination at the different representative monitoring points.; Physicochemical parameters and rainfall at 12 h before sampling influenced the load of enteric bacteria.; Risk maps showed areas highly prone to faecal pollution.; Human activities affected all regions in the representative monitoring points.;

Abstract Background Bacterial enteritis in growing pigs is a matter of concern in Danish pig production challenging herd health as well as production economy, and antimicrobial usage. The aim of this observational study using fecal sock samples was to determine the prevalence and excretion level of Lawsonia intracellularis (LI), Brachyspira pilosicoli (BP), Escherichia coli F4 (F4) and F18 (F18) and to investigate associations between prevalence or excretion levels of the bacteria and diarrhea. The study was performed in the late weaner and the early finisher period in herds with a history of diarrhea. Every weaner and finisher herd contributed with one sample each. Results In total, 47 weaner and 59 finisher herds were sampled. The overall prevalence and excretion levels (median and range in log(10) copies/gram of feces) were for LI 84.0% (median 6.2; range 3.0–7.7), for BP 45.2% (median 5.6; range 3.0–6.6), for F18 20.8% (median 5.7; range 4.7–7.7), and for F4 4.7% (median 5.5; range 5.2–6.0). In both diarrheic and non-diarrheic samples, the most prevalent bacteria were either LI alone or LI and BP in combination. In general, no association was found between increasing total bacterial excretion levels and diarrhea, but prevalence (p = 0.04) and excretion (p

Bacterial intercellular signaling mediated by small molecules, also called autoinducers (AIs), enables synchronized behavior in response to environmental conditions, and in many bacterial pathogens, intercellular signaling controls virulence gene expression. However, in the intestinal pathogen Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium), although three signals, named AI-1, AI-2 and AI-3, have been described, their roles in virulence remain elusive. AI-3 is the 3,6- isomer of a previously described Vibrio cholerae signaling molecule; 3,5-dimethylpyrazin-2-ol (3,5-DPO). To elucidate the role of AI-3/DPO in S. Typhimurium, we have mapped the global transcriptomic responses to 3,5- and 3,6-DPO isomers in S. Typhimurium. Our studies showed that DPO affects expression of almost 8% of all genes. Specifically, expression of several genes involved in gut-colonization respond to DPO. Interestingly, most of the affected genes are similarly regulated by 3,5-DPO and 3,6-DPO, respectively, indicating that the two isomers have overlapping roles in S. Typhimurium. [ABSTRACT FROM AUTHOR]

A total of 200 random samples of processed chicken meat products including frankfurter, luncheon, strips, and nuggets (50 of each) were collected from different supermarkets at Alexandria province. The samples were examined bacteriologically immediately after arrival to the laboratory for isolation and identification of some pathogenic bacteria that may contaminate these products as E. coli, Salmonellae, Campylobacter jejuni, and Staphylococcus aureus. The obtained results revealed that the incidence of E. coli in the examined samples of frankfurter, luncheon, strips, and nuggets was 10, 14, 6 and 0%, respectively. It was observed that the highest incidence was recorded in luncheon followed by frankfurter and lastly nuggets, the incidence of Salmonellae in the examined samples was 4, 6, 0 and 0%, respectively. The incidence of Y. enterocolitica in the examined samples of frankfurter, luncheon, strips, and nuggets was 4, 8, 2, and 2%, respectively. The incidence of C. jejuni in the examined samples of frankfurter, luncheon, strips, and nuggets was 6, 8, 0, and 2%, respectively. The incidence of S. aureus in the examined samples of frankfurter, luncheon, strips, and nuggets was 10, 8, 6, and 6%, respectively. Based on the recorded results in the current study, it was clear that the rates of isolation of the investigated enteric bacteria were higher in chicken frankfurter and luncheon as compared to strips and nuggets that may be attributed to the hygienic conditions of the working places and the awareness of the workers. [ABSTRACT FROM AUTHOR]

ABSTRACT The genus Salmonella comprises two species, Salmonella bongori and Salmonella enterica, which are infectious to a wide variety of animal hosts. The diversity within S. enterica has been further partitioned into 6–10 subspecies based on such features as host range, geography, and most recently, genetic relatedness and phylogenetic affiliation. Although Salmonella pathogenicity is attributable to large numbers of acquired virulence factors, the extent of homologous exchange in the species at large is apparently constrained such that the species and subspecies form distinct clusters of strains. To explore the extent of gene flow within and among subspecies, and to ultimately define true biological species, we evaluated patterns of recombination in over 1,000 genomes currently assigned to the genus. Those Salmonella subspecies containing sufficient numbers of sequenced genomes to allow meaningful analysis—i.e., subsp. enterica and diarizonae—were found to be reproductively isolated from one another and from all other subspecies. Based on the configuration of genomic sequence divergence among subspecies, it is expected that each of the other Salmonella subspecies will also represent a biological species. Our findings argue against the application of prescribed nucleotide-identity thresholds to delineate bacterial species and contend that the Biological Species Concept should not be disregarded for bacteria, even those, like Salmonella, that demonstrate complex patterns of species and subspecies divergence. IMPORTANCE The Biological Species Concept (BSC), which defines species boundaries based on the capacity for gene exchange, is widely used to classify sexually reproducing eukaryotes but is generally thought to be inapplicable to bacteria due to their completely asexual mode of reproduction. We show that the genus Salmonella, whose thousands of described serovars were formerly considered to be strictly clonal, undergoes sufficient levels of homologous recombination to be assigned to species according to the BSC. Aside from the two recognized species, Salmonella enterica and Salmonella bongori, several (and likely all) of the subspecies within S. enterica are reproductively isolated from one another and should each be considered a separate biological species. These findings demonstrate that species barriers in bacteria can form despite high levels of nucleotide identity and that commonly applied thresholds of genomic sequence identity are not reliable indicators of bacterial species status.

Background As an adjuvant therapy, probiotics can significantly improve the therapeutic effect in lupus nephritis. But there is a lack of comparative studies of efficacies of drug treatments and effects of probiotics on gut flora. Objective To observe the therapeutic efficacy, and gut flora changes induced by probiotics as an adjuvant therapy for lupus nephritis. Methods Ninety-eight patients with class Ⅳ andⅤlupus nephritis were selected from Department of Nephrology, Affiliated Hospital of Xiangnan University from 2019 to 2020, and randomized into a routine group (routine treatment) and an intervention group (routine treatment plus probiotics) under allocation concealment. Intergroup comparison of clinical efficacies was conducted after 24-week treatment in terms of levels of 24-hour urine protein, blood urea nitrogen, serum creatinine, serum IgE, IgG, and serum inflammatory markers, as well as fecal flora changes and fecal short-chain fatty acid concentrations. Results A total of 93 cases (46 in routine group, and 47 in intervention group) who completed the therapeutic follow-up were included for final analysis. Both groups had no statistically significant differences in sex ratio, mean age, BMI, baseline levels of systolic blood pressure, diastolic blood pressure, hemoglobin, serum albumin, serum creatinine, complement C3 and complement C4 (P>0.05) . At the end of treatment, the intervention group demonstrated lower mean Systemic Lupus Erythematosus Disease Activity Indexof Renal (P

Escherichia coli have served as important model organisms for over a century—used to elucidate key aspects of genetics, evolution, molecular biology, and pathogenesis. However, defining which strains actually belong to this species is erratic and unstable due to shifts in the characters and criteria used to distinguish bacterial species. Additionally, many isolates designated as E. coli are genetically more closely related to strains of Shigella than to other E. coli , creating a situation in which the entire genus of Shigella and its four species are encompassed within the single species E. coli. We evaluated all complete genomes assigned to E. coli and its closest relatives according to the biological species concept (BSC), using evidence of reproductive isolation and gene flow (i.e. homologous recombination in the case of asexual bacteria) to ascertain species boundaries. The BSC establishes a uniform, consistent, and objective principle that allows species-level classification across all domains of life and does not rely on either phenotypic or genotypic similarity to a defined type-specimen for species membership. Analyzing a total of 1,887 sequenced genomes and comparing our results to other genome-based classification methods, we found few barriers to gene flow among the strains, clades, phylogroups, or species within E. coli and Shigella. Due to the utility in recognizing which strains constitute a true biological species, we designate genomes that form a genetic cohesive group as members of E. coli BIO. [ABSTRACT FROM AUTHOR]

Abstract Introduction Periprosthetic joint infections (PJI) are a major complication in joint-arthroplasty. Rifampicin is often used as an additional agent to treat PJI, because it penetrates bacterial biofilms. However, rifaximin, belonging to the same antibiotic class as rifampicin, is frequently used to prevent episodes of hepatic encephalopathy in patients with cirrhosis and may induce resistance to rifampicin. The aim of this study was to examine the microbial pattern of periprosthetic joint infections in cirrhotic patients and to test the hypothesis that intake of rifaximin increases the rate of resistance to rifampicin in periprosthetic joint infections. Methods A cohort of cirrhotic patients and PJI (n = 25) was analysed on the characteristics of bacterial isolates from sonication and tissue analysis. In a second step a subgroup analysis on the development of rifampicin resistant bacterial specimens, depending on the intake of rifaximin (8 rifaximin intake patients vs. 13 non rifaximin intake patients) was performed. Results Intestinal bacteria were found in 50% of the specimens, which was significantly more frequent than in a control cohort. By comparison of the single bacterial isolates, rifampicin resistance was detected in 69.2% (9/13) of the rifaximin-intake samples. In contrast, the non-rifaximin-intake isolates only were resistant to rifampicin in 22.2% (4/18) of the cases (p = 0.01). The odds ratio for developing a rifampicin-resistance through rifaximin intake was calculated as OR = 13.5. Conclusion Periprosthetic joint infections have a high incidence of being caused by enteric bacteria in cirrhotic patients. Due to this change in microbial pattern and the innate resistance to rifampicin of most of gram-negative bacteria, the therapy with rifampicin should be carefully considered. The association between the use of rifaximin and developed resistance to rifampicin has a major impact on the treatment of PJI.

Background: Macrolides are considered one of the oldest classes of antibiotics which have been regarded among the best-tolerated antibiotic for almost several years. They are characterized by their large lactone ring structures and by their growth-inhibiting (bacteriostatic) effects on bacteria. Aim: The potency of macrolide antibiotics were determined against enteric bacteria (E. coli, Shigella spp. and Salmonella spp.) isolated during the raining season between June to September in the year 2018 from locations in Ado Ekiti metropolis. The consequences of the presence of these bacteria can be fatal hence the need to investigate their susceptibility to macrolide antibiotics. Methods: The bacteria were isolated from well water, soil and drainage samples obtained at Erifun, Omisanjana, Fiyinfoluwa, Ajilosun areas using serial dilution method. Results: It was observed that the bacteria were susceptible to 250 µg/mL and 500 µg/mL concentration of Azithromycin, Erythromycin, and Clarithromycin though with varying degrees of susceptibility. Azithromycin showed the highest potency. Conclusion: The present study indicated samples of the well water, soil and drainage at Erifun, Omisanjana, Ajilosun and Fiyinfoluwa areas of Ado-Ekiti were severely contaminated with E. coli, Salmonella spp., and Shigella spp. this is due to the lack of adequate sanitary measures. However, unhygienic behaviour like indiscriminate disposal of waste and open defecation should be discouraged.

The efficacy of leaf extracts of guava Psidium guajava (L.) were assessed on enteric bacteria isolated from two wells (W1 and W2) prone to faecal contamination in Akure, Nigeria. The load of enteric bacteria in the water samples was determined using a standard microbiological method. Leaf extracts of P. guajava (L.) were prepared using ethanol and hot distilled water and the antibacterial effects of the extracts on bacterial isolates were determined using the agar well diffusion method. Phytochemical components of the leaf extracts were carried out using standard methods. Results revealed the following mean concentrations of enteric bacteria in W1 and W2: Salmonella (3.8 and 3.9 log10 CFU/100 ml) and Shigella (3.6 and 3.7 log10 CFU/100 ml). The ethanol leaf extracts of P. guajava (L.) exhibited a zone of inhibition of 22 mm at 200 mg/ml on Shigella and no zone of inhibition was observed on Salmonella. The phytochemical components of ethanol and hot distilled water leaf extracts of P. guajava (L.) revealed the presence of saponin as (13.64 mg/g) and (59.82 mg/g). The findings of this study revealed that ethanol leaf extracts of P. guajava (L.) may be useful as an antibacterial agent against Shigella. HIGHLIGHTS The level of faecal pollution in the wells was 'critical' based on E. coli concentration.; Hot distilled water leaf extracts of guava had no effect on Salmonella and Shigella.; Resistance of Salmonella was plasmid-based.; Bioactive components of ethanol leaf extracts of P. guajava contributed to the antibacterial effect on Shigella.; Antibacterial potential of P. guajava leaves may be enhanced by extracting with ethanol.;

Background: Bacterial enteritis in growing pigs is a matter of concern in Danish pig production challenging herd health as well as production economy, and antimicrobial usage. The aim of this observational study using fecal sock samples was to determine the prevalence and excretion level of Lawsonia intracellularis (LI), Brachyspira pilosicoli (BP), Escherichia coli F4 (F4) and F18 (F18) and to investigate associations between prevalence or excretion levels of the bacteria and diarrhea. The study was performed in the late weaner and the early finisher period in herds with a history of diarrhea. Every weaner and finisher herd contributed with one sample each. Results: In total, 47 weaner and 59 finisher herds were sampled. The overall prevalence and excretion levels (median and range in log(10) copies/gram of feces) were for LI 84.0% (median 6.2; range 3.0–7.7), for BP 45.2% (median 5.6; range 3.0–6.6), for F18 20.8% (median 5.7; range 4.7–7.7), and for F4 4.7% (median 5.5; range 5.2–6.0). In both diarrheic and non-diarrheic samples, the most prevalent bacteria were either LI alone or LI and BP in combination. In general, no association was found between increasing total bacterial excretion levels and diarrhea, but prevalence (p = 0.04) and excretion (p < 0.01) level of F18 was found to be significantly higher in diarrheic samples. Further, a significant association was found between low LI excretion level and lack of diarrhea in weaner herds (p = 0.03). A significant positive correlation was found between excretion levels of LI and BP in diarrheic weaner herd samples (p = 0.02). Conclusion: Enteric pathogens were prevalent in a wide range of bacterial excretion levels in both diarrheic and non-diarrheic samples. Especially LI and BP were frequently found and with a positive correlation between excretion levels. Even in the absence of diarrhea, high prevalence and excretion levels of LI and BP were detected, thus making the status of diarrhea an insufficient tool for assessing the severity of their infections. [ABSTRACT FROM AUTHOR]

Recurrent pregnancy loss (RPL) is a major reproductive problem that affects approximately 5% of couples. The objective of this study was to assess vaginal flora dysbiosis in women suffering from unexplained RPL and to investigate the pathogenic properties of the microbiota associated with aerobic vaginitis (AV). The study included one hundred fifteen women, 65 with RPL and 50 controls. The diversity of vaginal microbiota isolated was evaluated by molecular sequencing. Then, pathogenic factors, such as acid-resistance, antibiotics susceptibility, and biofilm formation were evaluated. The prevalence of AV was five-fold higher in the RPL group than in the controls (64.6% vs. 12.0%). The most prevalent isolates in the case group were Enterococcus spp. (52%) and Staphylococcus spp. (26%). All bacterial strains tolerate low pH. The prevalence of multidrug resistance (MDR) among all bacteria was 47.7%. Of all strains, 91.0% were biofilm producers. The presence of MDR was found to be related to biofilm formation. The results provide evidence supporting an increased presence of dysbiosis of the vaginal flora, especially AV, in women with RPL in Tunisia. The viability of the AV-associated bacteria and their persistence in the genitals may be due to their ability to resist low pH and to produce a biofilm. [ABSTRACT FROM AUTHOR]

Bacteria respond to changes in their external environment, such as temperature, by changing the transcription of their genes. We know little about how these regulatory patterns evolve. We used RNA-seq to study the transcriptional response to a shift from 37°C to 15°C in wild-type Escherichia coli , Salmonella enterica , Citrobacter rodentium , Enterobacter cloacae , Klebsiella pneumoniae , and Serratia marcescens , as well as ∆ rpoS strains of E. coli and S. enterica . We found that these species change the transcription of between 626 and 1057 genes in response to the temperature shift, but there were only 16 differentially expressed genes in common among the six species. Species-specific transcriptional patterns of shared genes were a prominent cause of this lack of conservation. Gene ontology enrichment of regulated genes suggested many species-specific phenotypic responses to temperature changes, but enriched terms associated with iron metabolism, central metabolism, and biofilm formation were implicated in at least half of the species. The alternative sigma factor RpoS regulated about 200 genes between 37°C and 15°C in both E. coli and S. enterica , with only 83 genes in common between the two species. Overall, there was limited conservation of the response to low temperature generally, or the RpoS-regulated part of the response specifically. This study suggests that species-specific patterns of transcription of shared genes, rather than horizontal acquisition of unique genes, are the major reason for the lack of conservation of the transcriptomic response to low temperature., Importance: We studied how different species of bacteria from the same Family (Enterobacteriaceae) change the expression of their genes in response to a decrease in temperature. Using de novo -generated parallel RNA-seq data sets, we found that the six species in this study change the level of expression of many of their genes in response to a shift from human body temperature (37°C) to a temperature that might be found out of doors (15°C). Surprisingly, there were very few genes that change expression in all six species. This was due in part to differences in gene content, and in part due to shared genes with distinct expression profiles between the species. This study is important to the field because it illustrates that closely related species can share many genes but not use those genes in the same way in response to the same environmental change.

Objective: This systematic review aimed to (i) determine the risk of antimicrobial resistance (AMR) development associated with antimicrobial use (AMU) and other exposure factors in broilers, and (ii) identify best management practices to mitigate preharvest AMR development of enteric bacteria alongside broiler production., Methods: Study selection criteria comprised the population, exposure or intervention, comparator, and outcome framework and included broiler (population), AMU or other management practices (exposure or intervention), organic or antibiotic-free production (comparator), and the presence of AMR-enteric bacteria/genes (outcome). Peer-reviewed primary research studies were searched in PubMed on 19 December 2022, and AGRICOLA, Embase, Scopus, and Web of Science on 10 February 2023. The risk of bias in studies was assessed using the modified ROBIS-E risk of bias assessment tool. The results were synthesised and presented narratively according to PRISMA 2020 guidelines., Results: In total, 205/2699 studies were subjected to full-text review, with 15 included in the final synthesis. Enteric bacteria Escherichia coli, Salmonella , and Campylobacter exhibited AMR and multidrug resistance against several critically important antimicrobials (aminoglycoside, cephalosporin, chloramphenicol, macrolide, penicillin, quinolone, tetracycline, and sulfonamide) for human health. The risk of AMR development in bacteria was shown to be potentially higher with AMU in broiler production. Substandard farm management practices, poor biosecurity measures, and conventional production systems have also been associated with the dissemination of AMR in bacteria., Conclusions: Our findings indicate that AMU exposure is associated with considerably higher risk of AMR development in enteric bacteria. Antimicrobial stewardship, organic/antibiotic-free broiler production, good farm management practices, and high-level biosecurity measures are able to substantially mitigate preharvest AMR development in enteric bacteria. However, most of studies were cross-sectional, and therefore causal inference cannot be established., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Diarrhea is the second leading cause of morbidity and mortality worldwide among all ages, and one of the leading causes of poor health and premature death in the developing world. Microorganisms, such as viruses, bacteria, and parasites, are responsible for enteric infections among children. Excessive and inappropriate use of antimicrobial drugs and poor infection control practices have transformed antimicrobial resistance into a serious threat to public health worldwide. Therefore, it is essential to investigate the prevalence of enteric pathogens and the antimicrobial susceptibility patterns of bacterial pathogens., Objective: Assess the prevalence of enteric pathogens associated with diarrhea in children under 5 years at the Bule Hora Health Facility in 2021., Methods: An institution-based cross-sectional study was conducted from May 2021 to July 2021 in a Bule Hora Health Centre and Hospital. A total of 422 children with diarrhea were included in the study in the outpatient department. Sociodemographic and associated factors were evaluated using a pre-tested questionnaire. A sufficient amount of stool specimens was collected following standard microbiological procedures. An antigen detection kit was used to diagnose rotaviruses, parasites were examined using microscopy, and bacterial identification was carried out by culture and biochemical tests. The antibiotic susceptibility test of the bacterial isolates was performed using the Kirby-Bauer disc diffusion method. The data were analyzed using SPSS version 20. The p -value less than 0.05 was declared statistically significant., Results: The overall prevalence of enteropathogens in children under 5 years of age was 17%, with no mixed infections detected. Of this, 7.8% of the children's stool samples contained bacterial pathogens, 5% tested positive for rotavirus, and 4.2% contained intestinal parasites. Unprotected drinking water sources, poor carrier hand washing practices, and poor cleaning of utensils for child feeding were factors significantly associated with the prevalence of enteropathogens. Bacterial isolates have shown a high prevalence of resistance to amoxicillin., Conclusion: Therefore, it is important to take steps to reduce the spread of enteric pathogens among children under 5 years practicing good hygiene, ensuring sanitation, and providing clean drinking water. We recommend performing antimicrobial susceptibility tests before prescribing treatment to children with diarrhea., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Ashenafi, Tilahun, Aliyo and Sisay.)

Antibiotic resistance is an ongoing threat to both human and animal health. Migratory birds are a potential vector for the spread of novel pathogens and antibiotic resistance genes. To date, there has been no comprehensive study investigating the presence of antibiotic resistance (AMR) in the bacteria of Australian shorebirds or terns. In the current study, 1022 individual birds representing 12 species were sampled across three states of Australia (Victoria, South Australia, and Western Australia) and tested for the presence of phenotypically resistant strains of three bacteria with potential to be zoonotic pathogens; Escherichia coli, Enterococcusspp., and Salmonellasp. In total, 206 E. coli, 266 Enterococcusspp., and 20 Salmonellasp. isolates were recovered, with AMR detected in 42% of E. coli, 85% of Enterococcusspp., and 10% of Salmonellasp. Phenotypic resistance was commonly detected to erythromycin (79% of Enterococcusspp.), ciprofloxacin (31% of Enterococcusspp.) and streptomycin (21% of E. coli). Resident birds were more likely to carry AMR bacteria than migratory birds (p ≤.001). Bacteria isolated from shorebirds and terns are commonly resistant to at least one antibiotic, suggesting that wild bird populations serve as a potential reservoir and vector for AMR bacteria. However, globally emerging phenotypes of multidrug‐resistant bacteria were not detected in Australian shorebirds. This study provides baseline data of the carriage of AMR bacteria in Australian shorebirds and terns. [ABSTRACT FROM AUTHOR]

Gut microbes participate in pathogenesis by interacting with the host genome through epigenetic mechanisms, such as long non-coding RNAs. However, the mechanisms by which the microbiota induce expression alteration of long non-coding RNAs remains unclear. Here, we quantified the transcriptome alteration of human colon cell lines after being infected by a common enteric pathogen Salmonella typhimurium SL1344. We observed a widespread lncRNAs expression alteration. Among them, the elevated expression of LINC00152 was verified and proved to be induced by enteric bacteria-derived lipopolysaccharide (LPS). The inducible LINC00152 were found to inhibit Salmonella invasion and inflammation response. LINC00152 was overexpressed in tumors of the clinical CRC samples compared with adjacent normal tissues. Accordingly, we also demonstrated that overexpression of LINC00152 promoted the migration and invasion of colorectal cancer cells. Consistently, we observed an increased abundance of gram-negative bacteria and LPS in tumors tissue. Taken together, the above data implicated that enriched gram-negative bacteria in tumor tissue might promote tumor growth through modulating the expression of LINC00152. Furthermore, we demonstrated that LPS upregulated the expression of LINC00152 by introducing histone lactylation on its promoter and decreasing the binding efficiency of the repressor, YY1, to it. Our results provide new insights into how enterobacteria affect host epigenetics in human disease. [ABSTRACT FROM AUTHOR]

Background and Objective: Campylobacter is one of the most important pathogens causing bacterial gastroenteritis, which is usually transmitted through the food of animal origin. This study was done to evaluate the status of Campylobacter in diarrheal food outbreaks compared to other microbial agents. Methods: This descriptive study was performed on 305 diarrheal swab samples from 102 food outbreaks during six months from spring to the end of summer 2018. Presence of Campylobacter species were assessed according to the protocol of the General Directorate of Laboratory Affairs. Results: Out of 305 samples, 8 (2.6%) were identified as Campylobacter species, 3 (37.5%) Campylobacter and 5 (62.5%) Campylobacter coli. The epidemiology of the outbreaks showed that female (54.5%), average age of 16-30 years (28.2%), consumption of salads and vegetables (16.1%) and living in the cities (59.7%) were the most cases. Conclusion: This study showed that in addition to classic pathogens such as Salmonella, Shigella, Escherichia coli, attention also should be paid to Campylobacter bacteria. In addition, recognizing epidemiological factors can play an important role in preventing and controlling food outbreaks.

This research investigates the transferability of plasmid-mediated quinolone resistance (PMQR) genes among enteric bacteria isolates in human and animal samples, as well as its implication on resistance of recipient cells. A total of 1,964 strains of five different enteric bacteria species (Escherichia coli, Salmonella sp., Shigella sp., Klebsiella sp. and Aeromonas sp.) were screened for plasmid-mediated quinolone resistance (PMQR) genes from a population of quinolone resistant (Q-r) isolates. Screening for PMQR isolates was achieved by plasmid curing using sub-lethal concentration of Sodium Dodecyl Sulphate and PMQR genes (qnrA, qnrB, qnrS, Aac(6′)-Ib-crand Qep A) were detected by polymerase chain reaction (PCR). Conjugation and transformation experiments were attempted to ascertain transfer of genes from the Q-r isolates to a susceptible, standard recipient, E. coli J53-2. The minimum inhibitory concentration (MIC) was determined before and after gene transfer, using E-test strips. Results indicate that percentage resistance to the quinolones (Qs): Nalidixic acid, Ciprofloxacin, Pefloxacin and Ofloxacin determined by agar plate diffusion technique stood at 52.6, 47.3, 50.5, 70.6 and 46.0% for Escherichia coli, Salmonella sp., Shigellasp., Klebsiella sp. and Aeromonas sp. respectively. Analysis of variance indicated the occurrence of significant differences (F, 46.77–613.30; 0.00) in the resistance to each tested Qs. Generally, Human isolates showed greater resistance than Animal isolates (57.4 vs 47.2%). Investigation with specific primers indicated 11, 15, 7, 1 and 0 for qnrA, qnrB, qnrS, qepA and Aac(6′)-Ib-cr genes respectively, out of 1018 Q-r and 29 PMQR isolates. Gene transfer experiments indicated the transfer of all genes except qepA either by conjugation or transformation. The MIC of tested Qs on recipient bacterium before gene transfer greatly increased from 0.0625 to 0.25 µg/mL, after transfer. This study demonstrates that PMQR genes amongst enteric bacteria in the Niger delta of Nigeria were transferable and transfer conferred a higher Q- resistance on recipient bacterium.

Bacterial signal transduction systems sense changes in the environment and transmit these signals to control cellular responses. The simplest one-component signal transduction systems include an input sensor domain and an output response domain encoded in a single protein chain. Alternatively, two-component signal transduction systems transmit signals by phosphorelay between input and output domains from separate proteins. The membrane-tethered periplasmic bile acid sensor that activates the Vibrio parahaemolyticus type III secretion system adopts an obligate heterodimer of two proteins encoded by partially overlapping VtrA and VtrC genes. This co-component signal transduction system binds bile acid using a lipocalin-like domain in VtrC and transmits the signal through the membrane to a cytoplasmic DNA-binding transcription factor in VtrA. Using the domain and operon organization of VtrA/VtrC, we identify a fast-evolving superfamily of co-component systems in enteric bacteria. Accurate machine learning-based fold predictions for the candidate co-components support their homology in the twilight zone of rapidly evolving sequences and provide mechanistic hypotheses about previously unrecognized lipid-sensing functions. [ABSTRACT FROM AUTHOR]

Aim: This study was carried out to determine the microbial health risks associated with surface water commonly used for bathing, drinking, domestic and irrigational activities in Akure, Nigeria. Methods and Results: Water samples were collected from the river from March to June, 2018. The load of enteric bacteria, somatic coliphages and rotavirus in the water samples was determined using culture‐based methods and molecular technique. The physicochemical characteristics of the water samples were determined using standard methods. The risks of rotavirus, Salmonella and Shigella infections resulting from ingestion of the water from the river, were estimated using dose–response model. Redundancy analysis revealed that the levels of E. coli and Salmonella were highly associated with salinity and turbidity. The risks of infection associated with rotavirus (3.3 × 10−3) were higher than those associated with Salmonella (1.3 × 10−4) and Shigella (1.3 × 10−3), and were all above the WHO acceptable risk limit (10−4). Conclusion: Accidental or intentional ingestion of water from the river may pose potential risks of gastrointestinal illness to humans. Significance and Impact of study: Quantitative microbial risk assessment is essential in establishing adequate water management practices that must be strictly followed in order to protect human health. [ABSTRACT FROM AUTHOR]

Introduction: Periprosthetic joint infections (PJI) are a major complication in joint-arthroplasty. Rifampicin is often used as an additional agent to treat PJI, because it penetrates bacterial biofilms. However, rifaximin, belonging to the same antibiotic class as rifampicin, is frequently used to prevent episodes of hepatic encephalopathy in patients with cirrhosis and may induce resistance to rifampicin. The aim of this study was to examine the microbial pattern of periprosthetic joint infections in cirrhotic patients and to test the hypothesis that intake of rifaximin increases the rate of resistance to rifampicin in periprosthetic joint infections.Methods: A cohort of cirrhotic patients and PJI (n = 25) was analysed on the characteristics of bacterial isolates from sonication and tissue analysis. In a second step a subgroup analysis on the development of rifampicin resistant bacterial specimens, depending on the intake of rifaximin (8 rifaximin intake patients vs. 13 non rifaximin intake patients) was performed.Results: Intestinal bacteria were found in 50% of the specimens, which was significantly more frequent than in a control cohort. By comparison of the single bacterial isolates, rifampicin resistance was detected in 69.2% (9/13) of the rifaximin-intake samples. In contrast, the non-rifaximin-intake isolates only were resistant to rifampicin in 22.2% (4/18) of the cases (p = 0.01). The odds ratio for developing a rifampicin-resistance through rifaximin intake was calculated as OR = 13.5.Conclusion: Periprosthetic joint infections have a high incidence of being caused by enteric bacteria in cirrhotic patients. Due to this change in microbial pattern and the innate resistance to rifampicin of most of gram-negative bacteria, the therapy with rifampicin should be carefully considered. The association between the use of rifaximin and developed resistance to rifampicin has a major impact on the treatment of PJI. [ABSTRACT FROM AUTHOR]

Background: Foodborne diseases are caused by acquired pathogenic bacteria such as Salmonella enteritidis (S. enteritidis). It causes an intestinal imbalance, and the microbial toxins found in the gastrointestinal tract induces symptoms such as diarrhea. Coffee contains active ingredients such as antioxidants and is used as an anti-inflammatory agent by reducing pro-inflammatory cytokine levels in the body. Aim: The purpose of this study was to determine the interaction between Lampung robusta coffee and tissue damage in chickens infected by S. enteritidis. Methods: This study used first-day-old Isa brown layer chickens (n=60) divided into five treatment groups. The negative control group consists of healthy and normal chickens, whereas the positive control group consists of chickens infected with S. enteritidis bacteria at a concentration of 108 CFU/ml. Groups T1, T2, and T3 were given coffee extract with doses of 500 mg/kg BW (low dose), 1000 mg/kg BW (moderate dose), and 1500 mg/kg BW (high dose), respectively, then infected with S. enteritidis bacteria at a concentration of 108 CFU/ml. The coffee extract and bacteria were given orally via a feeding tube at a volume of 0.5 ml per chicks. The extract was given for 14 days (from day-3 to 16), and the bacteria were given on day-16 and 17. On day-18, the chickens were necropsied. Malondialdehyde (MDA) level was analyzed using One Way ANOVA test with GLM procedure (

We are interested in identifying and characterizing small molecule inhibitors of bacterial virulence factors for their potential use as anti-virulence inhibitors. We identified from high-throughput screening assays a potential activity for avasimibe, a previously characterized acyl-coenzyme A: cholesterol acyltransferase inhibitor, in inhibiting the NleB and SseK arginine glycosyltransferases from Escherichia coli and Salmonella enterica, respectively. Avasimibe inhibited the activity of the Citrobacter rodentium NleB, E. coli NleB1, and S. enterica SseK1 enzymes, without affecting the activity of the human serine/threonine N-acetylglucosamine (O-GlcNAc) transferase. Avasimibe was not toxic to mammalian cells at up to 200 µM and was neither bacteriostatic nor bactericidal at concentrations of up to 125 µM. Doses of 10 µM avasimibe were sufficient to reduce S. enterica abundance in RAW264.7 macrophage-like cells, and intraperitoneal injection of avasimibe significantly reduced C. rodentium survival in mice, regardless of whether the avasimibe was administered pre- or post-infection. We propose that avasimibe or related derivates created using synthetic chemistry may have utility in preventing or treating bacterial infections by inhibiting arginine glycosyltransferases that are important to virulence. [ABSTRACT FROM AUTHOR]

Aims: The biological events occurring during human digestion help to understand the mechanisms underlying the dose–response relationships of enteric bacterial pathogens. To better understand these events, we investigated the growth and reduction behaviour of bacterial pathogens in an in vitro model simulating the environment of the small intestine. Methods and Results: The foodborne pathogens Campylobacter jejuni, Listeria monocytogenes and Escherichia coli O157:H7 were cultured with multiple competing enteric bacteria. Differences in the pathogen's growth kinetics due to the relative amount of competing enteric bacteria were investigated. These growth differences were described using a mathematical model based on Bayesian inference. When pathogenic and enteric bacteria were inoculated at 1 log CFU per ml and 9 log CFU per ml, respectively, L. monocytogenes was inactivated over time, while C. jejuni and E. coli O157:H7 survived without multiplying. However, as pathogen inocula were increased, its inhibition by enteric bacteria also decreased. Conclusions: Although the growth of pathogenic species was inhibited by enteric bacteria, the pathogens still survived. Significance and Impact of the Study: Competition experiments in a small‐intestine model have enhanced understanding of the infection risk in the intestine and provide insights for evaluating dose–response relationships. [ABSTRACT FROM AUTHOR]