Pathogens

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20 pages, 1249 KiB

Open AccessArticle

The Anti-Listeria Activity of Pseudomonas fluorescens Isolated from the Horticultural Environment in New Zealand

by Vathsala Mohan, Reginald Wibisono, Saili Chalke, Graham Fletcher and Françoise Leroi

Pathogens 2023, 12(2), 349; https://doi.org/10.3390/pathogens12020349 - 19 Feb 2023

Cited by 1 | Viewed by 1704

Abstract

Beneficial bacteria with antibacterial properties are attractive alternatives to chemical-based antibacterial or bactericidal agents. Our study sourced such bacteria from horticultural produce and environments to explore the mechanisms of their antimicrobial properties. Five strains of Pseudomonas fluorescens were studied that possessed antibacterial activity [...] Read more.

Beneficial bacteria with antibacterial properties are attractive alternatives to chemical-based antibacterial or bactericidal agents. Our study sourced such bacteria from horticultural produce and environments to explore the mechanisms of their antimicrobial properties. Five strains of Pseudomonas fluorescens were studied that possessed antibacterial activity against the pathogen Listeria monocytogenes. The vegetative culture of these strains (Pseudomonas fluorescens-PFR46I06, Pseudomonas fluorescens-PFR46H06, Pseudomonas fluorescens-PFR46H07, Pseudomonas fluorescens-PFR46H08 and Pseudomonas fluorescens-PFR46H09) were tested against Listeria monocytogenes (n = 31), Listeria seeligeri (n = 1) and Listeria innocua (n = 1) isolated from seafood and horticultural sources and from clinical cases (n = 2) using solid media coculture and liquid media coculture. All Listeria strains were inhibited by all strains of P. fluorescens; however, P. fluorescens-PFR46H07, P. fluorescens-PFR46H08 and P. fluorescens-PFR46H09 on solid media showed good inhibition, with average zones of inhibition of 14.8 mm, 15.1 mm and 18.2 mm, respectively, and the other two strains and P. fluorescens-PFR46H09 had a significantly greater zone of inhibition than the others (p < 0.05). There was no inhibition observed in liquid media coculture or in P. fluorescens culture supernatants against Listeria spp. by any of the P. fluorescens strains. Therefore, we hypothesized that the structural apparatus that causes cell-to-cell contact may play a role in the ejection of ant-listeria molecules on solid media to inhibit Listeria isolates, and we investigated the structural protein differences using whole-cell lysate proteomics. We paid special attention to the type VI secretion system (TSS-T6SS) for the transfer of effector proteins or bacteriocins. We found significant differences in the peptide profiles and protein summaries between these isolates’ lysates, and PFR46H06 and PFR46H07 possessed the fewest secretion system structural proteins (12 and 11, respectively), while PFR46H08 and PFR46H09 had 18 each. P. fluorescens-PFR46H09, which showed the highest antimicrobial effect, had nine tss-T6SS structural proteins compared to only four in the other three strains. Full article

(This article belongs to the Special Issue Viral Diseases, Bacterial Infections, and Antimicrobial Resistance)

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11 pages, 2101 KiB

Open AccessArticle

Monitoring of Antimicrobial Resistance of Salmonella Serotypes Isolated from Humans in Northwest Italy, 2012–2021

by Monica Pitti, Aitor Garcia-Vozmediano, Clara Tramuta, CeRTiS Clinical Laboratories Group, Cristiana Maurella and Lucia Decastelli

Pathogens 2023, 12(1), 89; https://doi.org/10.3390/pathogens12010089 - 05 Jan 2023

Cited by 2 | Viewed by 2394

Abstract

Salmonella enterica is among the most common causes of foodborne outbreaks in humans in Europe. The global emergence of resistance to antimicrobials calls for close monitoring of the spread and prevalence of resistant Salmonella strains. In this study, we investigated the occurrence of [...] Read more.

Salmonella enterica is among the most common causes of foodborne outbreaks in humans in Europe. The global emergence of resistance to antimicrobials calls for close monitoring of the spread and prevalence of resistant Salmonella strains. In this study, we investigated the occurrence of antimicrobial resistance of Salmonella serotypes isolated from humans between 2012 and 2021 in Piedmont, northwest Italy. A total of 4814 Salmonella strains (168 serotypes) were tested against six classes of antimicrobials. Many strains (83.3%) showed resistance to at least one antibiotic: tetracycline (85.1%), ampicillin (79.2%), quinolones (47.4%), and gentamicin (28.4%). Between the first (2012–2016) and the second study period (2017–2021), a decrease in antimicrobial resistance was noted for tetracycline (from 92.4% to 75.3%), ampicillin (from 85.3% to 71.3%), quinolones (from 49.4% to 44.6%), and cefotaxime (from 34.8% to 4.0%). Many multidrug resistant Salmonella strains (43.6%) belonged to S. ser. Typhimurium, S. ser. Infantis, and S. ser. Typhimurium 1,4,[5],12:i:-. Overall, multidrug resistance decreased from 60.7% to 26.4%, indicating a reduction in the antimicrobial resistance of Salmonella strains in Piedmont and in Europe and demonstrating the effectiveness of the measures that were put in place to reduce antimicrobial resistance. Full article

(This article belongs to the Special Issue Viral Diseases, Bacterial Infections, and Antimicrobial Resistance)

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11 pages, 620 KiB

Open AccessArticle

Multidrug-Resistant Gram-Negative Bacteria Contaminating Raw Meat Sold in Accra, Ghana

by Deric A. Baah, Fleischer C. N. Kotey, Nicholas T. K. D. Dayie, Francis S. Codjoe, Patience B. Tetteh-Quarcoo and Eric S. Donkor

Pathogens 2022, 11(12), 1517; https://doi.org/10.3390/pathogens11121517 - 11 Dec 2022

Cited by 7 | Viewed by 2004

Abstract

Background: Efforts to combat antimicrobial resistance (AMR) should be based on the One Health approach, involving human health, animal health, and the environment. In Ghana, previous studies on AMR have given little attention to animal source food, a major route of transmission of [...] Read more.

Background: Efforts to combat antimicrobial resistance (AMR) should be based on the One Health approach, involving human health, animal health, and the environment. In Ghana, previous studies on AMR have given little attention to animal source food, a major route of transmission of antibiotic-resistant zoonotic pathogens. The aim of this study was to investigate the occurrence of multidrug-resistant (MDR) bacteria in meat sold in Accra. Methods: This was a cross-sectional study in which 270 meat samples (90 each of beef, goat meat, and chicken) were collected, and investigated for contamination with multidrug-resistant bacteria. The bacteria were subjected to susceptibility testing against amikacin (30 µg), ampicillin (10 µg), amoxicillin-clavulanate (20/10 µg), cefuroxime (30 µg), ceftriaxone (30 µg), ceftazidime (30 µg), cefepime (30 µg), ciprofloxacin (5 µg), trimethoprim-sulfamethoxazole (1.25/23.75 µg), ertapenem (10 µg), meropenem (10 µg), imipenem (10 µg), tigecycline (15 µg), and gentamicin (10 µg). Results: Thirty-two different types of bacteria, totalling 558, were isolated, the predominant being Escherichia coli (44.6%), Aeromonas hydrophila (19.9%), Vibrio cholerae (3.4%), Aeromonas veronii (3.2%), and Klebsiella pneumoniae (3.1%). The prevalence of MDR among the contaminating bacteria was 14.9%. The MDR distribution among the predominant bacteria was Escherichia coli (18.7%), Aeromonas hydrophila (11.1%), Vibrio cholerae and Aeromonas veronii (0.0% each), and K. pneumoniae (5.6%). Moreover, 2.0% of the contaminating bacteria were extended-spectrum beta-lactamase (ESBL) producers, all of which occurred in the chicken samples, and their distribution was: Escherichia coli (1.3%), Klebsiella pneumoniae, Pantoea spp., Enterobacter cloacae, and Serratia plymuthica (0.2% each). Conclusions: The meat samples were heavily contaminated with Escherichia coli and Aeromonas hydrophila, and less frequently, with Vibrio cholerae, Klebsiella pneumoniae, and other organisms. The prevalence of multidrug-resistant bacteria was moderate (14.9%), while that of ESBL producers was low (2%). Full article

(This article belongs to the Special Issue Viral Diseases, Bacterial Infections, and Antimicrobial Resistance)

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12 pages, 942 KiB

Open AccessArticle

Epidemiology of Community-Acquired Sepsis: Data from an E-Sepsis Registry of a Tertiary Care Center in South India

by Fabia Edathadathil, Soumya Alex, Preetha Prasanna, Sangita Sudhir, Sabarish Balachandran, Merlin Moni, Vidya Menon, Dipu T. Sathyapalan and Sanjeev Singh

Pathogens 2022, 11(11), 1226; https://doi.org/10.3390/pathogens11111226 - 24 Oct 2022

Cited by 1 | Viewed by 1476

Abstract

The study aims to characterize community-acquired sepsis patients admitted to our 1300-bedded tertiary care hospital in South India from the Surviving Sepsis Campaign (SSC) guideline-compliant e-sepsis registry stratified by focus of infection. The prospective observational study recruited 1009 adult sepsis patients presenting to [...] Read more.

The study aims to characterize community-acquired sepsis patients admitted to our 1300-bedded tertiary care hospital in South India from the Surviving Sepsis Campaign (SSC) guideline-compliant e-sepsis registry stratified by focus of infection. The prospective observational study recruited 1009 adult sepsis patients presenting to the emergency department at the center based on Sepsis-2 criteria for a period of three years. Of the patients, 41% were between 61 and 80 years with a mean age of 57.37 ± 13.5%. A total of 13.5% (136) was under septic shock and in-hospital mortality for the study cohort was 25%. The 3 h and 6 h bundle compliance rates observed were 37% and 49%, respectively, without significant survival benefits. Predictors of mortality among patients with bloodstream infections were septic shock (p = 0.01, OR 2.4, 95% CI 1.23–4.79) and neutrophil-to-lymphocyte ratio (p = 0.008, OR 1.01, 95% CI 1.009–1.066). The presence of Acinetobacter (p = 0.005, OR 4.07, 95% CI 1.37–12.09), Candida non-albicans (p = 0.001, OR16.02, 95% CI 3.0–84.2) and septic shock (p = 0.071, OR 2.5, 95% CI 0.97–6.6) were significant predictors of mortality in patients with community-acquired pneumonia. The registry has proven to be a key data source detailing regional microbial etiology and clinical outcomes of adult sepsis patients, enabling comprehensive evaluation of regional community-acquired sepsis to tailor institutional sepsis treatment protocols. Full article

(This article belongs to the Special Issue Viral Diseases, Bacterial Infections, and Antimicrobial Resistance)

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10 pages, 986 KiB

Open AccessArticle

Genotypic and Phenotypic Characteristics of Moraxella catarrhalis from Patients and Healthy Asymptomatic Participants among Preschool Children

by Na Zhao, Hongyu Ren, Jianping Deng, Yinju Du, Qun Li, Pu Zhou, Haijian Zhou, Xiangkun Jiang and Tian Qin

Pathogens 2022, 11(9), 984; https://doi.org/10.3390/pathogens11090984 - 29 Aug 2022

Cited by 2 | Viewed by 1574

Abstract

(1) Background: M. catarrhalis can ascend into the middle ear, where it is a prevalent causative agent of otitis media in children, or enter the lower respiratory tract, where it is associated with community-acquired pneumonia (CAP). In this study, we aimed to [...] Read more.

(1) Background: M. catarrhalis can ascend into the middle ear, where it is a prevalent causative agent of otitis media in children, or enter the lower respiratory tract, where it is associated with community-acquired pneumonia (CAP). In this study, we aimed to provide an overview of the prevalence of M. catarrhalis in preschool children. (2) Methods: M. catarrhalis strains were isolated from samples. All isolates were characterized in terms of serotypes (STs), virulence genes, multilocus sequence type, and antibiotic susceptibility. (3) Results: The percentages of strains expressing lipooligosaccharides (LOSs), serotype A, B, C, or unknown were 67.61%, 15.71%, 4.28%, and 12.38%, respectively. Among the strains, 185 (88.10%) carried ompB2, 207 (98.57%) carried ompE, and 151 (71.90%) carried ompCD. The most frequently identified STs were ST449 (n = 13), ST64 (n = 11), and ST215 (n = 10). The resistance rates to the antibiotics cefuroxime, azithromycin, and erythromycin were 43.33%, 28.10%, and 39.05%, respectively. (4) Conclusions: High prevalence of some-specific ST types and high rates of antibiotic resistance indicate the necessity for an increased vigilance of resistant strains, a rational use of antibiotics in preschool children, and most importantly, the surveillance of healthy asymptomatic participants preschool children with M. catarrhalis. Our findings provide a platform for the development of novel M. catarrhalis vaccines. Full article

(This article belongs to the Special Issue Viral Diseases, Bacterial Infections, and Antimicrobial Resistance)

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Review

Jump to: Research, Other

18 pages, 5043 KiB

Open AccessReview

Interaction of Microbes with Microplastics and Nanoplastics in the Agroecosystems—Impact on Antimicrobial Resistance

by Jayashree Nath, Jayita De, Shantanu Sur and Pratik Banerjee

Pathogens 2023, 12(7), 888; https://doi.org/10.3390/pathogens12070888 - 29 Jun 2023

Cited by 4 | Viewed by 5264

Abstract

Microplastics (MPs) and nanoplastics (NPs) are hotspots for the exchange of antimicrobial resistance genes (ARGs) between different bacterial taxa in the environment. Propagation of antimicrobial resistance (AMR) is a global public health issue that needs special attention concerning horizontal gene transfer (HGT) under [...] Read more.

Microplastics (MPs) and nanoplastics (NPs) are hotspots for the exchange of antimicrobial resistance genes (ARGs) between different bacterial taxa in the environment. Propagation of antimicrobial resistance (AMR) is a global public health issue that needs special attention concerning horizontal gene transfer (HGT) under micro-nano plastics (MNPs) pressure. Interactions between MNPs and microbes, or mere persistence of MNPs in the environment (either water or soil), influence microbial gene expressions, affecting autochthonous microbiomes, their resistomes, and the overall ecosystem. The adsorption of a range of co-contaminants on MNPs leads to the increased interaction of pollutants with microbes resulting in changes in AMR, virulence, toxin production, etc. However, accurately estimating the extent of MNP infestation in agroecosystems remains challenging. The main limitation in estimating the level of MNPs contamination in agroecosystems, surface and subsurface waters, or sediments is the lack of standardized protocols for extraction of MPs and analytical detection methods from complex high organic content matrices. Nonetheless, recent advances in MPs detection from complex matrices with high organic matter content are highly promising. This review aims to provide an overview of relevant information available to date and summarize the already existing knowledge about the mechanisms of MNP-microbe interactions including the different factors with influence on HGT and AMR. In-depth knowledge of the enhanced ARGs propagation in the environment under the influence of MNPs could raise the needed awareness, about future consequences and emergence of multidrug-resistant bacteria. Full article

(This article belongs to the Special Issue Viral Diseases, Bacterial Infections, and Antimicrobial Resistance)

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37 pages, 1441 KiB

Open AccessReview

Resistance, Tolerance, Virulence and Bacterial Pathogen Fitness—Current State and Envisioned Solutions for the Near Future

by Veronica Lazar, Eliza Oprea and Lia-Mara Ditu

Pathogens 2023, 12(5), 746; https://doi.org/10.3390/pathogens12050746 - 22 May 2023

Cited by 3 | Viewed by 2965

Abstract

The current antibiotic crisis and the global phenomena of bacterial resistance, inherited and non-inherited, and tolerance—associated with biofilm formation—are prompting dire predictions of a post-antibiotic era in the near future. These predictions refer to increases in morbidity and mortality rates as a consequence [...] Read more.

The current antibiotic crisis and the global phenomena of bacterial resistance, inherited and non-inherited, and tolerance—associated with biofilm formation—are prompting dire predictions of a post-antibiotic era in the near future. These predictions refer to increases in morbidity and mortality rates as a consequence of infections with multidrug-resistant or pandrug-resistant microbial strains. In this context, we aimed to highlight the current status of the antibiotic resistance phenomenon and the significance of bacterial virulence properties/fitness for human health and to review the main strategies alternative or complementary to antibiotic therapy, some of them being already clinically applied or in clinical trials, others only foreseen and in the research phase. Full article

(This article belongs to the Special Issue Viral Diseases, Bacterial Infections, and Antimicrobial Resistance)

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Other

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12 pages, 2309 KiB

Open AccessSystematic Review

Amoxicillin-Resistant Streptococci Carriage in the Mouths of Children: A Systematic Review and Meta-Analysis

by Ayrton G. Araújo Júnior, Marina L. V. A. Costa, Felipe R. P. Silva, Daniel D. R. Arcanjo, Lúcia F. A. D. Moura, Felipe A. A. Oliveira, Maria J. S. Soares and Patrick V. Quelemes

Pathogens 2022, 11(10), 1114; https://doi.org/10.3390/pathogens11101114 - 28 Sep 2022

Cited by 2 | Viewed by 2002

Abstract

Streptococcal bacteremia that occurs during invasive dental procedures can lead to infective endocarditis (IE) in children with certain heart diseases. Prior to such procedures, antibiotic prophylaxis (AP) with amoxicillin (AMPC) is recommended. However, the detection of amoxicillin-resistant strains (AMPC-RS) in the mouths of [...] Read more.

Streptococcal bacteremia that occurs during invasive dental procedures can lead to infective endocarditis (IE) in children with certain heart diseases. Prior to such procedures, antibiotic prophylaxis (AP) with amoxicillin (AMPC) is recommended. However, the detection of amoxicillin-resistant strains (AMPC-RS) in the mouths of children with heart diseases raises the concern that they would be uncovered by the action of standard AP. This work carried out a systematic review and meta-analysis regarding AMPC-RS carriage in the mouths of children. We consulted databases covering studies between the years 2000 and 2021, following the PRISMA declaration. A meta-analysis was carried out to assess the prevalence of children carrying AMPC-RS in the mouths. The antimicrobial tests were carried out by microdilution (46.2% of articles), disk diffusion (38.3%), and the E-test (15.4%). Streptococcus mitis and S. sanguinis were bacteria with the most found resistance phenotype, with MIC reaching values of 128 µg/mL. Of the 13 selected articles, only 6 presented results that made it possible to calculate the prevalence of children carrying AMPC-RS in their mouths, ranging from 5.5% to 86.3%. Most of the studies were classified as high quality, and the collected data demonstrate the presence of streptococcal strains with different levels of resistance in the collected samples, such as the dental plaque. The meta-analysis pointed to evidence of AMPC-RS being carried, with a prevalence of 21.3% (I² = 0%, p = 0.705). There is an important prevalence of AMPC-RS carriage in the mouths of children. Specific attention should be directed to AP in those susceptible to IE. Full article

(This article belongs to the Special Issue Viral Diseases, Bacterial Infections, and Antimicrobial Resistance)

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