Understanding the problem of antibiotic resistance

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Antibiotics are drugs designed to kill bacteria or inhibit their growth. They are grouped into classes according to how they work against bacteria—and, while some treat specific types of bacteria, others combat a broad range of bacteria species. The most important thing to know about antibiotics is that we rely on them to treat bacterial infections in both people and animals.
Unfortunately, the use of antibiotics can also contribute to antibiotic resistance in bacteria.

What is antibiotic resistance?

Antibiotic resistance occurs when bacteria develop ways to overcome the drugs designed to fight them.

Bacteria can develop resistance to multiple antibiotics, and these bacteria are referred to as multi-drug resistant. And, some bacteria are resistant to all antibiotics.

These resistance traits can be passed not only from one generation of bacteria to the next, but also shared between bacteria through various genetic elements. This means antibiotic-resistant bacteria can rapidly spread between and among animals and humans.

Why antibiotic resistance matters

Antibiotics are critical, often life-saving tools in our fight against infectious diseases in people and animals. Antibiotic resistance makes these bacterial infections harder to treat, as it limits—or even completely removes—treatment options. The fewer treatment options there are, the greater the chance of prolonged illness, the need for more intensive care, disability, and even death—and of greater financial costs of care. It also means that chemotherapy and surgeries that increase the risk of bacterial infection become even riskier.

Antibiotic resistance is increasing rapidly in bacterial populations across the world, becoming a top global health issue. Multi-drug resistant bacteria are a particular threat, as several bacteria that can cause serious infections have become resistant to all or most available antibiotics. This includes antibiotics typically used only as a final resort, as when other antibiotics fail. At the same time, the discovery of new antibiotics to take their place is slowing.

What is contributing to antibiotic resistance?

The main reason for the acceleration in antibiotic resistance is misuse and overuse of antibiotics in people and in animals. Here are some common examples:

  • Using antibiotics when they aren’t necessary, such as for viral infections or noninfectious diseases
  • Using the wrong antibiotic to treat an infection
  • Not completing the full prescribed course of antibiotics, or using antibiotics for longer than necessary
  • Using antibiotics without a physician’s or veterinarian’s recommendation
  • Using antibiotics to prevent disease or promote growth in farm animals
  • Improperly disposing of unused antibiotics, such as by dumping them down the drain or flushing them down the toilet
  • When antibiotics are misused in animals, this can lead to development of resistant bacteria, endangering not only the animals themselves but, potentially, us all.

Misuse and overprescribing of antibiotics in animals also may lead to short-term antibiotic shortages that make effective treatments harder to get, as well as increased costs and, ultimately, tighter restrictions around antibiotic use in animals. Such restrictions could involve a total ban on the veterinary use of certain antibiotics important for human health care—which often are important for pets and other veterinary patients, too.

How veterinarians help fight antibiotic resistance

Veterinarians are the only people who have the training and experience necessary to ensure that antibiotic use in animals is appropriate, effective, and safe.

To ensure the best possible outcomes, veterinarians need to conduct in-person examinations of animals—or the premises where the animals are kept, in the case of food-producing animals—to gather the information necessary for determining the most appropriate course of action. In-person exams also allow for any needed laboratory testing to confirm infection and choose the right antibiotic.

In-person examinations and premise visits by a licensed veterinarian also provide confidence to federal and state legislators that antibiotics are being appropriately used, which in turns safeguards our access to antibiotics for animals.

Without hands-on information, antibiotics might be inappropriately prescribed or used, which could further promote antibiotic resistance and endanger other animals, public health, and the environment.

How animal owners help fight antibiotic resistance

Assuring that antibiotics continue to be effective for your animals, your family, and others requires collaboration between the people who prescribe them and the people who use them. This includes not only human health professionals and patients but also veterinarians, pet owners, farmers, and other animal caretakers.

As an animal owner, here’s how you can help curb antibiotic resistance:

  • Reduce your animal’s need for antibiotics by having them vaccinated, as recommended by your veterinarian.
  • Take steps to prevent potential infection-causing bacteria from spreading, such as regularly washing your hands and properly disposing of animal waste.
  • Insist on an in-person visit with your veterinarian if your animal is ill.
  • Avoid pressuring your veterinarian to prescribe antibiotics.
  • If antibiotics are prescribed, follow your veterinarian’s directions. Do not stop giving antibiotics before the recommended treatment period is over, or continue giving them after this period.
  • Keep antibiotics out of reach of animals and children to prevent accidental ingestion.
  • Return unused antibiotics to your pharmacist or veterinarian for disposal, or turn them over to a local medicine take-back program.
  • Support state laws that protect animal and public health by limiting the conditions by which antibiotics may be prescribed and used in animals, to safeguard our use of these critical drugs.

Antibiotic resistance is a complex problem without a simple solution. We all have a role to play in keeping resistance in check.

Antimicrobial use and resistance: FAQs for pet owners

Antimicrobial use and antimicrobial resistance are complex issues. These frequently asked questions and their answers offer science-based information to help you make educated decisions about antibiotics and other antimicrobial drugs.

Learn more

Antimicrobials and livestock

Due to concerns about the growing problem of antibiotic resistance, a Veterinary Feed Directive (VFD)—which is essentially a veterinarian's order or prescription—is needed whenever food animals are to be given antibiotics that are important in human medicine.

  • These medications are only available for purchase when accompanied by a veterinarian's order. A livestock owner can’t run to a feed or supply store to pick up a commercially available medically important antibiotic to be used in feed or water.
  • Medically important antibiotics can’t be used for production purposes, such as growth promotion and feed efficiency. Any production use of medically important antibiotics is illegal.
  • Antibiotics are still readily available, with plenty of antibiotic options to protect animal health. Owners or caretakers of food-producing animals simply need to work with a veterinarian and establish a veterinarian-client-patient relationship (VCPR) to ensure that animals receive the most appropriate treatment.