Antibiotics resistance

The ability of bacteria to survive exposure to antibiotics that once killed them — one of the gravest threats to modern medicine and food safety alike. Resistance arises through reduced drug permeability, modification of the drug or its target, efflux pumps, and enzymes that destroy the antibiotic. Bacteria acquire these tricks by spontaneous mutation or by swapping genes with neighbours through conjugation and transduction; plasmids carrying multiple resistance genes can spread across species. In the food chain, resistant bacteria travel on meat, produce and in farm environments, which is why prudent antibiotic use in agriculture is a global public-health priority.