Characterization and Antibiotic Susceptibility Profiles of Pathogenic Escherichia Coli Isolated from Diarrhea Samples within the Buffalo City Metropolitan Municipality, Eastern Cape, South Africa

Antimicrobial Susceptibility and Characterization of Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolated from Stools of Primary Healthcare Patients in Ethiopia

Antimicrobial resistance of Escherichia coli is a growing problem in both developed and developing countries. This study aimed to investigate the phenotypic antimicrobial resistance of E. coli isolates (n = 260) isolated from the stool specimen of patients attending public health facilities in Addis Ababa and Hossana. This study also aimed to characterize phenotypically confirmed extended-spectrum beta-lactamase (ESBL)-producing E. coli isolates (n = 22) using whole-genome sequencing. Resistance to 18 different antimicrobials was assessed using the disc diffusion method according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. The highest resistance rate among the E. coli isolates was found for ampicillin (52.7%), followed by trimethoprim-sulfamethoxazole (29.6%). Of all isolates, 50 (19.2%) were multidrug-resistant and 22 (8.5%) were ESBL producers. ESBL genes were detected in 94.7% of the sequenced E. coli isolates, and multiple β-lactamase genes were detected in 57.9% of the isolates. The predominant ESBL gene identified was blaCTX-M-15 (78.9%). The blaTEM-1B gene was detected in combination with other ESBL genes in 57.9% of the isolates, while only one of the sequenced isolates contained the blaTEM-1B gene alone. The blaCTX-M-3 gene was detected in three isolates. The genes blaCTX-M-15 and blaTEM-1B as well as blaCTX-M-15 and blaTEM-169 were confirmed to coexist in 52.6% and 10.5% of the sequenced E. coli isolates, respectively. In addition, blaOXA-1 was identified together with blaCTX-M-15 and blaTEM-1B in one isolate, and in one isolate, blaTEM-169 together with blaCTX-M-15 and blaTEM-1B was found. The results obtained show that measures need to be taken to reduce the spread of drug resistance and ensure the long-term use of available antimicrobials.

Antimicrobial resistance genes of Escherichia coli, a bacterium of "One Health" importance in South Africa: Systematic review and meta-analysis

This is a systematic review and meta-analysis that evaluated the prevalence of Escherichia coli antibiotic-resistant genes (ARGs) in animals, humans, and the environment in South Africa. This study followed Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to search and use literature published between 1 January 2000 to 12 December 2021, on the prevalence of South African E. coli isolates' ARGs. Articles were downloaded from African Journals Online, PubMed, ScienceDirect, Scopus, and Google Scholar search engines. A random effects meta-analysis was used to estimate the antibiotic-resistant genes of E. coli in animals, humans, and the environment. Out of 10764 published articles, only 23 studies met the inclusion criteria. The obtained results indicated that the pooled prevalence estimates (PPE) of E. coli ARGs was 36.3%, 34.4%, 32.9%, and 28.8% for bla_TEM-M-1 , ampC, tetA, and bla _TEM, respectively. Eight ARGs (bla_CTX-M , bla_CTX-M-1 , bla_TEM , tetA, tetB, sul1, sulII, and aadA) were detected in humans, animals and the environmental samples. Human E. coli isolate samples harboured 38% of the ARGs. Analyzed data from this study highlights the occurrence of ARGs in E. coli isolates from animals, humans, and environmental samples in South Africa. Therefore, there is a necessity to develop a comprehensive "One Health" strategy to assess antibiotics use in order to understand the causes and dynamics of antibiotic resistance development, as such information will enable the formulation of intervention strategies to stop the spread of ARGs in the future.

The Resistance Patterns in E. coli Isolates among Apparently Healthy Adults and Local Drivers of Antimicrobial Resistance: A Mixed-Methods Study in a Suburban Area of Nepal

Evidence-based decision-making to combat antimicrobial resistance (AMR) mandates a well-built community-based surveillance system for assessing resistance patterns among commensals and pathogenic organisms. As there is no such surveillance system in Nepal, we attempted to describe the antimicrobial resistance pattern in E. coli isolated from the fecal samples of apparently healthy individuals in Dhulikhel municipality and also explored the local drivers of AMR. We used a mixed-method design with a cross-sectional quantitative component and a descriptive qualitative component, with focus group discussion and key informant interviews as the data collection method. Fecal samples were collected from 424 individuals randomly selected for the study. E. coli was isolated from 85.9% of human fecal samples, of which 14% were resistant to ≥3 class of antimicrobials (multidrug resistant). Of the 368 isolates, resistance to ampicillin (40.0%), tetracycline (20.7%) and cefotaxime (15.5%) were most prevalent. The major drivers of AMR were: lack of awareness of AMR, weak regulations on sales of antimicrobials, poor adherence to prescribed medications, and incomplete dosage due to financial constraints. These findings indicate the need for strict implementation of a national drug act to limit the over-the-counter sales of antimicrobials. Additionally, awareness campaigns with a multimedia mix are essential for educating people on AMR.