Acinetobacter baumannii (Ab) has increasingly been identified as a cause of hospital-acquired infections and epidemics. The rise of carbapenem-resistant Acinetobacter baumannii (CRAB) poses significant challenges in treatment. Nosocomial outbreaks linked to CRAΒ A. baumannii strains have been reported worldwide, including in Greece. This study aimed to analyze the molecular epidemiology trends of multidrug-resistant A. baumannii isolates in a tertiary hospital in Athens, Greece. A total of 43 clinical isolates of extensively drug-resistant (XDRAB), pan-drug-resistant (PDRAB), and CRAB were collected from patients suffering from blood infection, hospitalized between 2016 and 2020 at the internal medicine clinics and the ICU. A.baumannii isolates underwent testing for Ambler class B and D carbapenemases and the detection of ISAba1, and were typed, initially, using pulsed-field gel electrophoresis, and, subsequently, using sequence-based typing and multiplex PCR to determine European Clone lineages. The bla_OXA-23 gene accompanied by ISAba1 was prevalent in nearly all A. baumannii isolates, except for one carrying bla_OXA-58. The intrinsic bla_OXA-51-like gene was found in all isolates. No Ambler class B carbapenemases (VIM, NDM) were detected. Isolates were grouped into four PF-clusters and no one-cluster spread was documented, consistent with the absence of outbreak. The study indicated that XDR/PDR-CRAB isolates predominantly produce OXA-23 carbapenemase and belong to European Clone II. Further research is needed to understand the distribution of resistant bacteria and develop effective prevention and control strategies.

Antibiotic-resistant bacteria (ARB) are present in wastewaters as their elimination during treatment in wastewater treatment plants (WWTPs) is often impossible. Water plays an important role in the spread of these microorganisms among humans, animals and the environment. This study aimed to assess the antimicrobial resistance patterns, resistance genes and molecular genotypes by means of phylogenetic groups of E. coli isolates in aquatic habitats, including sewage and receiving water bodies, as well as clinical settings in the Boeotia regional district of Greece. The highest resistance rates among both environmental and clinical isolates were observed to be for penicillins, ampicillin and piperacillin. Resistance patterns related to extended spectrum β-lactamases (ESBL) production and ESBL genes were also detected in both environmental and clinical isolates. Phylogenetic group B2 was predominant in clinical settings and the second most frequent among wastewaters, whereas group A was dominant in all environmental isolates. In conclusion, the studied river water and wastewaters may serve as reservoirs of resistant E. coli isolates that pose potential threats to both human and animal health.

We survey the diversity of antimicrobial resistance profiles of Escherichia coli (E. coli) isolates and molecular genotypes by means of phylogenetic groups circulating in complex aquatic habitats, such as sewage and receiving waters bodies as well as in clinical environment in Boeotia regional district of Greece. The predominant resistant profile among all environmental and clinical isolates was to penicillins - ampicillin (AMP) and piperacillin (PIP). ESBLs resistance related profiles were observed both in environmental and clinical isolates. Phylogenetic group B2 was the predominant in clinical isolates, whilst group A was dominant in environmental isolates. We report that reclaimed river water and wastewater are reservoirs of R and MDR E. coli to commonly used antibiotics in clinical practice posing putative threats for human and animal health.

The first prospective surveillance of ESBL and colistin-resistant Escherichia coli recovered from sick pigs from a slaughterhouse in Central Greece aimed to investigate the spread of relevant genetic elements. In February 2021, 25 E. coli isolates were subjected to antimicrobial susceptibility testing using disk diffusion and broth microdilution techniques. PCR screening was conducted to identify ESBLs and mcr genes. Additional assays, encompassing mating-out procedures, molecular typing utilizing Pulsed-Field Gel Electrophoresis, multilocus sequence typing analysis, and plasmid typing, were also conducted. A 40% prevalence of ESBLs and an 80% prevalence of MCR-1 were identified, with a co-occurrence rate of 32%. The predominant ESBL identified was CTX-M-3, followed by SHV-12. Resistance to colistin, chloramphenicol, cotrimoxazol, and ciprofloxacin was detected in twenty (80%), fifteen (60%), twelve (48%), and four (16%) isolates, respectively. All bla_CTX-M-3 harboring plasmids were conjugative, belonging to the incompatibility group IncI1, and approximately 50 kb in size. Those carrying bla_SHV-12 were also conjugative, classified into incompatibility group IncI2, and approximately 70 kb in size. The mcr-1 genes were predominantly located on conjugative plasmids associated with the IncX4 incompatibility group. Molecular typing of the ten concurrent ESBL and MCR-1 producers revealed seven multilocus sequence types. The heterogeneous population of E. coli isolates carrying resistant genes on constant plasmids implies that the dissemination of resistance genes is likely facilitated by horizontal plasmid transfer.

The purpose of this study was to investigate the knowledge, attitudes, and behaviors of Greek undergraduate students on hand hygiene and mobile phone hygiene, in relation to their mobile phones’ microbial load. An anonymous self-reported questionnaire was distributed among 100 students and swabs were taken from their devices for microbiological cultures and for an on-site bioluminescence microbial load assessment. Hand washing was considered the most effective personal protective behavior by the majority (89%), while spatial restrictions (40%) and forgetfulness (31%) were the main reasons for neglecting hand washing. Most students washed their hands 6–10 times/day (32%) for approximately 11–20 s (35%). Although most devices were cleaned/disinfected within the last week (28%), many were contaminated with Staphylococcus saprophyticus (84%), Staphylococcus aureus (13%), and Escherichia coli (39%), while 75% of the samples exceeded the “fail” threshold limit of the luminometer’s measurements. Moreover, statistically significant differences (p < 0.05) were found between the devices’ microbial load and certain hand hygiene behaviors and preferences. The median cfu/cm² of Escherichia coli was higher among first-year students of health sciences, while Staphylococcus aureus was more prevalent in females’ than in males’ mobile phones. It w therefore understood that undergraduate students’ knowledge, attitudes, and behaviors on hand hygiene and mobile phone hygiene are highly intertwined with the microbial load on their mobile phones.

Background/Objectives: Over the past decade, extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli have emerged as a significant public health concern due to their potential to spread beyond clinical settings and healthy carriers, in various environments, including in animal source foods. This study seeks to investigate the molecular characteristics of ESBL-producing E. coli strains isolated from food of animal origin, with a focus on chromosomal typing, plasmid typing, and the description of the associated resistance genes’ genetic environment. Methods: Ninety-seven food of animal origin samples were tested for E. coli isolates resistant to cefotaxime. The resulting isolates were then subjected to antimicrobial susceptibility testing and PCR analysis to detect beta-lactamase genes. Additional assays, encompassing mating-out procedures, molecular typing utilizing Pulsed-Field Gel Electrophoresis, Multilocus Sequence Typing Analysis, and Oxford Nanopore Technology Lite whole plasmid sequencing, were also conducted. Results: E. coli was detected in 26 raw food specimens, generating a percentage of 27%. Fourteen of the current isolates (14%) were resistant to third generation cephalosporins, producing CTX-M-1, CTX-M-15, CTX-M-55, and SHV-12 beta-lactamases. The respective genes were accompanied by Insertion Sequences ISEcp1 and IS26, facilitating their transfer. Among plasmids harboring ESBL genes, representatives belonging to incI1 incompatibility group prevailed (5/8), followed by IncY and IncX3. Most plasmids proved conjugative. Diversity of molecular fingerprints of ESBL producing E. coli was revealed. Conclusions: To the best our knowledge, this study is the first to describe the molecular characteristics of E. coli isolates producing ESBLs sourced from foods of animal origin in Greece. The prevalence of ESBLs in our confined food collection is primarily associated with the very successful IncI1 plasmids, which were not linked to a specific E. coli genetic background. This lack of association confirms that horizontal plasmid transfer plays a more significant role than clonal dissemination in the spread of ESBL-mediated cephalosporin resistance.