Colonization and Microbial Contamination of Public Washrooms by Multidrug Resistant Gram-negative Bacteria: a pilot study

Author: Inês Catarina Vieira Lourenço Scientific Coordinator: Professor João Perdigão Institution: iMed ULisboa, Faculty of Pharmacy of the University of Lisbon

INTRODUCTION: Antimicrobial resistance (AMR) is the ability of microorganisms to resist antibiotics. It is the main infectious health problem in the countries of the European Economic Area (EU / EEA) and one of the main causes of concern in public health. Inadequate use or prescription of antibiotics, insufficient prevention, and control of infections in hospitals are the main factors supporting the development of AMR. The main cause for this phenomenon is associated with the high rate of prescription of this type of drug, including its excess or inadequate prescription. Other causes may include the consumption and use of antibiotics in agriculture, climate change and chemotherapy in cancer patients. The most commonly reported bacterial species associated with invasive infections in the EU/ EEA area were Escherichia coli, followed by Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanni, Pseudomonas aeruginosa, Enterococcus Faecalis and Enterococcus Faecium. AMR’s cost to savings is significant. In addition to death and disability, prolonged illness results in longer hospital stays, the need for more expensive drugs and financial challenges for patients. The health cost of infections caused by AMR bacteria in the EU/EEA population is comparable to that of influenza, tuberculosis and HIV/AIDS combined.

AIM: That said, the aim of this pilot study was not only to investigate the contamination of public restrooms by Gram-negative bacteria with resistance to third generation cephalosporins or carbapenems, but also to characterize drug susceptibility profiles and identify isolates at the level of species.

MATERIAL AND METHODS: Eight samples were collected in toilets, faucets, and sanitary brushes at the Faculty of Pharmacy of the University of Lisbon. The samples were subjected to isolation of Gram-negative bacteria resistant to third generation carbapenems, cephalosporins and antibiotic susceptibility testing, DNA extraction, PCR amplification, purification, and bioinformatics analysis. resistant to the antibiotics studied was detected in taps or toilets, suggesting a greater degree of sanitation when compared to sanitary brushes. Seven clinical isolates belonging to the orders Entrobacteriales (n=2) and Pseudomonadales (n=5) were identified at the level of sanitary brushes.

CONCLUSION: The highest degree of intrinsic resistance of the isolates belonging to the order Pseudomonadales stands out. However, one of the isolates belonging to the order Enterobacteriales and identified as belonging to the genus Klebsiella showed concomitant resistance to third 6 generation cephalosporins, fluoroquinolones and aminoglycosides, highlighting the need to proceed with the characterization of the respective genetic determinants and genetic context.

Questions & answers

Please, tell us a little bit more about yourself. My name is Inês Lourenço, I am a student in the fourth year of Pharmaceutical Sciences in the Faculty of Pharmacy of the University of Lisbon, Portugal. I have always been a curious person, attentive to the world around me and with a great desire to know more about the themes that fascinate me; among them have always been music, sports and science. This diversity of interests led me to several extracurricular activities such as studying piano for 10 years, doing theater, learning new languages, volunteering and having been a federated athlete in Basketball and Synchronized Swimming. Aside from that, in 2019 I founded a small embroidery business, taking my granny hobby to another level.

Tell us a bit more about your research and its significance. I started this journey back in 2020 in the Research Institute for Medicines, iMedULisboa. I knew I wanted to study and investigate a field that was preponderant in public health, so I chose Antimicrobial Resistance (AMR) I find this area particularly interesting and relevant since AMR is the leading infectious health issue across the European Economic Area (EU/EEA) countries and one of the major causes of concern for public health. It has become a such global emergency that WHO has declared that AMR is one of the top 10 global public health threats facing humanity. Recent estimates based on data from EARSNet show that each year, more than 670 000 infections occur in the EU/EEA due to bacteria resistant to antibiotics and that approximately 33 000 people die as a direct consequence of these infections. My research showed that there are resistant bacteria contamination in the sanitary facilities of my faculty, since one of the isolates, belonging to the order Enterobacteriales and identified as Klebsiella, showed concomitant resistance to third generation cephalosporins, fluoroquinolones and aminoglycosides.

What was the biggest challenge while carrying out the research and how did you overcome that? The biggest challenge that I, and most people doing research, had to face was the restrictions due to the pandemic. I was not able to go to the lab as many times as I would have liked to in order to produce more and better results. The only way around this issue was to do as much as possible every time I could meet with my coordinator and really took the time to understand everything that I was doing, its purpose and final results. I was very grateful for the opportunity that I was being given, working with great scientists and with every material I needed, so I tried to make the most out of it.

In your opinion, what is the benefit of joining ESSP and what advice do you have for students undertaking research in the future? Having our abstract published in ESSP is a great opportunity for students to share our work and knowledge. This exchange of ideas is crucial in making better science and starting discussions that can lead to amazing discoveries. EPSA’s initiatives, like ESSP, help us develop not only as students but as future health care professionals and European citizens. The best piece of advice I can give is to never underestimate yourself and to be resilient during your studies and research. The results may not correspond to your expectations, but you will always learn from the process.