Antibiotics are given to food animals, such as pigs, chickens, and cows, to prevent disease but also to encourage growth. Their overuse can result in bacteria that are resistant to common antibiotics and are no longer useful in treating disease in humans.
- Risks to humans: Overuse of antibiotics in food animals can cause development of drug resistance in bacteria that infect animals. These antibiotics then become less useful, or even ineffective, in fighting disease in humans. Another problem is that the drug-resistant bacteria may infect humans directly, such as when we eat meat contaminated by bacteria.
- Treating and preventing disease in food animals: Antibiotics are used to treat diseases in food animals but are also given to prevent them from getting sick in overcrowded conditions. Some other ways to keep animals healthy include reducing crowding, and vaccination against common illnesses.
- Using antibiotics to promote animal growth: A major use of antibiotics is not only to treat and prevent disease in food animals, but also to increase their weight gain.
- Government action: The Centers for Disease Control (CDC), the World Health Organization (WHO), and the US Food and Drug Administration (FDA) support ending the use of antibiotics in food animals for nontherapeutic uses, that is, for uses that are not directly treating disease. Congress is also considering legislation that would ban certain antibiotics for nontherapeutic uses.