Antibiotic resistance: Understanding the connection to antibiotic use in animals raised for food

For both humans and animals, misusing and overusing antibiotics can lead to the development and spread of antibiotic-resistant bacteria. These may cause untreatable infections.

By Mayo Clinic Staff

Antibiotics are strong medications designed to kill bacteria or stop their growth. But sometimes antibiotics can be harmful. For both people and animals, the misuse and overuse of antibiotics can lead to the growth and spread of antibiotic-resistant bacteria. This may lead to infections that are resistant to antibiotic treatment.

All animals have bacteria in their intestines. Animals that are raised for food are given antibiotics to treat infection and kill some bacteria. But some bacteria are resistant to antibiotics, and resistant bacteria will often survive and multiply.

Antibiotic-resistant bacteria can then spread from these animals to:

  • Other animals raised in the same location
  • Animal products people eat, such as chicken and steak
  • Produce, such as fruits and vegetables, through unclean water or soil
  • The environment, through animal feces
  • Prepared food, through unclean surfaces, such as a cutting board that's used to cut chicken and then chop vegetables and not washed between uses

You can become sick with bacterial infections that are resistant to antibiotics in several ways, including when you:

  • Eat food that's been infected with antibiotic-resistant bacteria and not properly prepared or cooked
  • Handle unclean animals and don't wash your hands
  • Touch or use unclean surfaces and don't wash your hands or clean surfaces

Bacterial infections that are resistant to antibiotics can lead to mild illnesses. In some cases, they can cause severe illnesses that take a long time to recover from and may lead to death.

In the United States, the Food and Drug Administration (FDA) controls antibiotic use in people and animals. In animals raised for food, FDA-approved antibiotic uses include:

  • Treating sick animals
  • Controlling illness in a group of animals when some of the animals are sick
  • Preventing illness in a group of animals at risk of becoming sick

The FDA and Centers for Disease Control and Prevention recommend antibiotics be used in animals raised for food only when needed to ensure the animal's health, not to promote growth. A doctor who treats animals (veterinarian) should direct or guide these conditions.

July 14, 2020 See more In-depth