Resistance Science: Antibiotics in Agriculture The Risk to Human Health It is estimated that more than half of the antibiotics in the United States are used in animal food production. The excessive use of antimicrobials in food animal production is an underestimated problem. In both human and veterinary medicine, the risk of developing resistance increases whenever bacteria are exposed to antimicrobials. Resistance opens the door to therapeutic failure for even the most common pathogens and leads to an increasing number of infections. Growing evidence of the relationship between the use of antimicrobials in animal husbandry and the increase in bacterial resistance in humans has led scientific authorities in several countries, including the United States, to review several agricultural practices. Overview of the relationship between antimicrobial use in animal feed Antibiotic production and resistance Exposure to antimicrobials radically alters microbial ecosystems in humans, animals and the environment, which can lead to the development of antimicrobial resistance. ...