Widespread use of antibiotics leads to the development and spread of more antibiotic-resistant bacteria, like MRSA. When used, antibiotics kill off susceptible bacteria leaving resistant ones to multiply and spread; greater use of antibiotics—wherever that occurs—translates into greater numbers and different varieties of drug-resistant bacteria. Infections in hospitals are often resistant to many antibiotics due to widespread antibiotic use there. Bacteria from farms also are often resistant to the multiple antibiotics routinely used on many farms.

This article was adapted from a factsheet compiled by Keep Antibiotics Working (KAW)