The Global Threat of Carbapenem-Resistant Gram-Negative Bacteria

Antimicrobial resistance in bacteria is a public health complex issue, accelerated by the inadequate use of antibiotics and driven by many interconnected factors. It is far from being restricted to clinical settings, considering antimicrobial compounds are used in livestock and agriculture for several non-clinical reasons. Also, antibiotics and their metabolites are eventually released by patients and animals through environmental matrices, posing a selection pressure on environmental bacteria to acquire or develop antimicrobial resistance. Antimicrobial resistant bacteria (ARB) and antimicrobial resistance genes (ARGs) are considered emerging environmental contaminants, and among all matrices, water is the main vehicle for their spread through soil, urban surfaces, animals and human beings.

Carbapenem-resistant Gram-negative bacteria are the most critical microorganisms listed by the World Health Organization (WHO) as the priority pathogens that pose a great threat to human health. They can cause severe and often deadly infections, as well as they carry resistance-encoding genes that can be easily spread among bacteria, especially at (but not restricted to) environments where antibiotic selective pressure is applied. Treatment options for infections caused by carbapenem-resistant bacteria are scarce. In many cases, they are also resistant to aminoglycosides, polymyxins and tigecycline, and the alternatives end up being the use of newer antibiotics and synergistic combinations.

Carbapenem resistance usually emerge after the acquisition of genes by bacterial conjugation or other horizontal transfer pathways, which can occur in several microbiomes, like the human or animal gut or environmental matrices. The resistance can then be spread through vertical multiplication of bacteria, generating successful resistant clones, or through the transfer of their resistance-encoding genes to other bacteria, which occurs mostly by plasmids. Although carbapenems are mostly used in the human clinical practice, reports of carbapenemase-producing bacteria isolated from animal and environmental sources suggest that the prevention of their spread urges for a One Health approach. Surveillance of clones and resistance genetic determinants can lead to an adequate infection treatment in a hospital environment, as well as it can avoid the spread of resistance if it is extended to other fields, like hospital effluents, sewage treatment plants and animal husbandry sources.

This Research Topic welcomes submissions of manuscripts in all acceptable formats, including original research articles, method articles, case studies and reviews that address carbapenem resistance. We are interested in the following areas or research:

·      surveillance studies conducted in hospitals, communities and the environment (e.g. water, sewage, soil, urban surfaces),

·      beyond the bedside: carbapenemase-producing bacteria isolated from animal and environmental sources,

·      description and characterization of new carbapenem-resistance enzymes or mechanisms,

·      newly discovered treatment options,

·      new detection methods,

·      human, animals and environmental microbiome studies,

·      whole-genome sequencing (WGS) characterization of carbapenemase-producing strains,