antimicrobial resistance

Antibiotic resistance tests: Bacteria are streaked on solid medium in Petri dishes and paper disks are laid on the surface, each impregnated with a different antibiotic. Clear rings, such as those on the left, show that bacteria have not grown around the disks, indicating that these bacteria are not resistant. The bacteria on the right are fully resistant to three of seven and partially resistant to two of seven antibiotics tested.

Antimicrobial resistance (AMR or AR) occurs when microbes evolve mechanisms that protect them from antimicrobials, which are drugs used to treat infections in humans, animals, and plants. Any microbe can develop resistance, including bacteria (antibiotic resistance), viruses (antiviral resistance), parasites (antiparasitic resistance), and fungi (antifungal resistance). Together, these adaptations fall under the AMR umbrella, posing a challenge to all countries and all demographics. Misuse and improper management of antimicrobials are primary drivers of this resistance, though it can also occur naturally through genetic mutations and the spread of resistant genes. Microbes resistant to multiple drugs are termed multidrug-resistant (MDR) and are sometimes called superbugs.