Microbiology · Infectious Disease

Antibiotic Resistance

Bacteria culture

Antibiotic resistance is one of the most pressing threats to global public health. It occurs when bacteria evolve mechanisms to survive exposure to antibiotics that were once effective against them, rendering standard treatments ineffective and turning common infections into potentially life-threatening conditions.

700K deaths attributed globally each year
10M projected annual deaths by 2050
~70% of antibiotics used in livestock farming

Mechanisms of Resistance

Bacteria develop resistance through several distinct pathways: altering the molecular targets that antibiotics bind to, producing enzymes that destroy or inactivate the drug, and deploying efflux pumps — molecular machines that actively expel the antibiotic from the cell before it can take effect.

Horizontal Gene Transfer

Resistant strains can pass resistance genes to other bacteria — including unrelated species — at remarkable speed, spreading the problem far beyond a single organism.

Mutational Adaptation

Under antibiotic pressure, only the most resistant individuals survive and reproduce, giving rise to entirely new resistant populations through natural selection.

Drivers of the Crisis

The primary drivers include overuse and misuse of antibiotics: self-medication, incomplete treatment courses, and widespread prophylactic use in agriculture. Globalisation and international travel accelerate the spread of resistant strains across borders, transforming local outbreaks into global public health emergencies.

"The world is heading toward a post-antibiotic era, in which common infections and minor injuries can once again kill."
— World Health Organization

Strategies and Solutions

Combating resistance demands a multifaceted approach: developing new antibiotic classes, enforcing strict prescription controls, educating patients and healthcare providers, and fostering international epidemiological surveillance networks. Vaccination, rapid point-of-care diagnostics, and bacteriophage therapy are emerging as promising alternatives to conventional antibiotics.