Related Experiment Video
Updated: May 8, 2026
06:56
Detection of Horizontal Gene Transfer Mediated by Natural Conjugative Plasmids in E. coli
Published on: March 24, 2023
[Plasmid-mediated colistin resistance in pathogenic bacteria]
Néstor Casillas-Vega1, Soraya Mendoza-Olazarán2
1Universidad Autónoma de Nuevo León, Hospital Universitario Dr. José Eleuterio González, Departamento de Patología Clínica. Monterrey, Nuevo León, Mexico.
Summary
Plasmid-mediated colistin resistance (mcr) is a growing threat, spreading globally in humans, animals, and the environment. Urgent action is needed to combat this resistance and prevent a post-antibiotic era.
Area of Science:
- Microbiology
- Genetics
- Public Health
Background:
- Plasmid-mediated colistin resistance (mcr) poses a significant global health threat, compromising treatments for multidrug-resistant Gram-negative bacilli.
- Colistin remains a critical last-resort antibiotic, making the spread of mcr resistance particularly alarming.
Purpose of the Study:
- To systematically review and critically analyze the literature on mcr colistin resistance from 2015-2025.
- To assess the global distribution, prevalence, genetic variants, mechanisms, diagnostics, and clinical impact of mcr genes.
Main Methods:
- Comprehensive literature search across PubMed, Scopus, GenBank, and WHO reports.
- Systematic review and critical analysis of collected data.
Main Results:
- Widespread dissemination of mcr genes observed in humans, animals, and the environment, with high prevalence in Asia and increasing rates in Latin America.
- Emergence of concerning variants like mcr-3 and mcr-9, often co-occurring with carbapenemase genes, increasing the risk of pan-resistant strains.
- Clinical infections linked to high mortality, extended hospital stays, and increased healthcare costs; asymptomatic carriage facilitates silent spread.
Conclusions:
- Plasmid-mediated colistin resistance is a complex, multifaceted challenge requiring immediate, coordinated global action.
- Strengthening surveillance, developing rapid diagnostics, regulating polymyxin use, and exploring new therapies are crucial to mitigate this threat.
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