antibioticresistant

Antibiotic resistance is the ability of bacteria to survive exposure to antibiotics that would normally kill them or stop their growth. It can be intrinsic, meaning some species naturally resist certain drugs, or acquired through mutations or by obtaining resistance genes from other bacteria. Resistance emerges when antibiotics are used, overused, or misused, and when infection control is inadequate.

Bacteria resist antibiotics through several mechanisms, including enzymatic inactivation of drugs (for example beta-lactamases that destroy penicillins), alterations of drug targets, increased efflux of drugs, and reduced permeability. Resistance can spread within and between bacterial species via horizontal gene transfer, such as conjugation and transformation, and through clonal expansion of resistant strains.

The rise of antibiotic resistance has major health and economic implications. It can lead to longer illnesses, more hospitalizations, higher mortality, and greater treatment costs. Well-known resistant pathogens include methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), extended-spectrum beta-lactamase (ESBL) producing Enterobacterales, and carbapenem-resistant Enterobacteriaceae (CRE). Drug-resistant Neisseria gonorrhoeae and multidrug-resistant Pseudomonas aeruginosa are also concerns in many settings.

Prevention and response rely on antibiotic stewardship to promote appropriate use, vaccination where available, and robust infection prevention and hygiene practices. Safe food handling, clean water, and rapid diagnostics support surveillance and containment. A One Health approach, linking human, animal, and environmental health, is increasingly emphasized. Ongoing research aims to develop new antibiotics, alternative therapies, and better diagnostic tools to address the threat.