Emergence of Extended-Spectrum Cephalosporin- and Colistin-Resistant Enterobacterales in Otherwise Healthy University Students.

Resistance to last resort antibiotics has been increasing, particularly in low- and middle-income countries such as Lebanon, which has well established challenges in antimicrobial stewardship and other public health and environmental issues. However, data on the emergence of antibiotic resistance in the community in Lebanon are limited. In this study, we assessed resistance to last resort antibiotics in the fecal samples of 111 otherwise healthy university students in north Lebanon. The results showed that 47.7% of the samples harbored extended-spectrum cephalosporin-resistant isolates, while 2.7% of the samples yielded colistin-resistant isolates. Furthermore, molecular analyses showed that the ß-lactamase gene group, blaCTX-M-1 group, was detected in the majority (93%) of screened extended-spectrum ß-lactamase isolates. In addition, the colistin-resistant Escherichia coli isolates carried mcr-1, including the novel mcr-1.26 variant, which was previously reported in clinical samples as well as in domesticated animals and the environment in Lebanon. Taken together, these findings highlight the occurrence of resistance to important antibiotics in the community, perhaps suggesting diffuse sources, including clinical and environmental settings, and multiple factors driving the spread of multidrug-resistant bacteria and resistance determinants. There is a pressing need for comprehensive antimicrobial stewardship programs and the implementation of evidence-based practices in clinical and community settings to mitigate the increasing spread of antimicrobial resistance.

Spread of ESC-, carbapenem- and colistin-resistant Escherichia coli clones and plasmids within and between food workers in Lebanon.

OBJECTIVES: Knowledge on the dynamic of MDR Escherichia coli in the human community is still limited, especially in low- and middle-income countries. Our goal was to decipher the dynamics of E. coli lineages and plasmids resistant to ESC, carbapenem and colistin within and between food workers in Lebanon using genomic-based approaches. METHODS: Eighty-four healthy adults working in three bakeries were sampled twice at a 6 monthly interval. E. coli resistant to ESC (ESC-E), carbapenem (CP-E) and colistin (CO-E) were collected on selective plates. Non-duplicate isolates were whole-genome sequenced using the Illumina technology and plasmid transmission was assessed by long-read sequencing. Data were analysed using bioinformatics tools and SNP-based phylogeny. RESULTS: ESC-E carriage rate reached 34.5% (t0) and 52.9% (t6), and 15 workers were positive at both t0 and t6. Carbapenem resistance (blaOXA-181, blaOXA-204, blaNDM-5) was found in five workers at t0 and two at t6, while colistin resistance (mcr-1.1) was found in five workers at t0 and one at t6. Forty-seven different STs were identified, of which three STs were predominant (ST131, n = 9; ST10, n = 5; ST69, n = 5). One worker presented the same ESC-E clone at t0 and t6. Twelve different events of clonal transmission among individuals were exemplified while plasmid transmission was only shown once. CONCLUSIONS: Our study revealed a high carriage rate of MDR E. coli (60.7%) and the emergence of CP and colistin resistance in the Lebanese community. Incidental and long-term ESC-E carriage was observed in 41.7% and 17.9% of the workers, respectively. The high clonal diversity suggests an important dynamic of acquisition and loss of MDR E. coli and limited plasmid spread.

WGS Analysis of Clonal and Plasmidic Epidemiology of Colistin-Resistance Mediated by mcr Genes in the Poultry Sector in Lebanon.

Poultry and poultry meat are important contributors to the global antimicrobial burden. Unregulated and illegal use of extended-spectrum cephalosporins (ESC) in this sector has long been identified as a major cause of massive spread of ESC-resistant Escherichia coli, and colistin usage is considered a main driver of plasmid-mediated mcr genes dissemination. In Lebanon, the first mcr-1-positive E. coli found in poultry dates back to 2015, followed by a few reports of mcr-1-positive E. coli in poultry, swine, humans, and the environment. On the contrary, a comprehensive picture of the population structure of mcr-1-positive E. coli and mcr-1-bearing plasmids carrying the mcr-1 gene using whole-genome analysis is largely lacking. This study reports the prevalence of mcr-1-positive E. coli in poultry originating from 32 farms across three Lebanese governorates and slaughtered in the same place. We report 27/32 (84.4%) mcr-1 positive farms, leading to a total of 84 non-duplicate E. coli collected, of which 62 presented the mcr-1 gene. Numerous associated resistances were identified, including to ESC through the presence of bla CTX-M or bla CMY genes. The mcr-1 gene was mostly carried by IncX4 (n = 36) and IncI2 (n = 24) plasmids, which are both known for their efficient transfer capacities. A high genetic diversity was detected, arguing for the lack of contamination during the slaughter process. ST744 and ST1011 were the most widely identified clones, which have been both regularly associated to mcr-1-carrying E. coli and to the poultry sector. The wide dissemination of colistin-resistance, coupled to resistances to ESC and numerous other molecules, should urge authorities to implement efficient guidelines for the use of antibiotics in the poultry sector in Lebanon.

Epidemiology of antimicrobial resistance in Lebanese extra-hospital settings: An overview.

Antibiotics can truly be considered the symbol of the 20th century's miracle drugs. However, excessive and inappropriate use of antibiotics in human and veterinary medicine has led to repercussions in terms of mortality, morbidity, and financial and societal costs, especially with the lack of novel drugs to combat infections caused by antimicrobial-resistant pathogens. Unfortunately, antimicrobial resistance (AMR) has increased significantly worldwide in the past decades, particularly in developing third-world countries. Hence, various key organisations have made AMR the focus of highly visible reports, conferences and actions. Nevertheless, the majority of investigations were initiated in the developed world. In Lebanon, as in other developing countries, AMR remains responsible for significant morbidity and mortality. Whilst a large number of studies have targeted the AMR crisis in Lebanese clinical settings, its epidemiological situation in animals, foodstuffs and the environment is still unclear in this country. In this context, and in order to better survey, control and prevent the emergence of multidrug-resistant bacterial strains in Lebanese non-clinical settings, this work reviewed the available data on the epidemiology of antimicrobial-resistant bacteria isolated from Lebanese extra-hospital sources.