Antimicrobials - resistance; Antimicrobial agents - resistance; Drug-resistant bacteria
Using antibiotics incorrectly can cause some bacteria to change or permit resistant bacteria to grow. These changes make bacteria stronger, so most or all antibiotic medicines no longer work to kill them. This is called antibiotic resistance. Resistant bacteria continue to grow and multiply, making infections harder to treat.
Antibiotics work by killing bacteria or keeping them from growing. Resistant bacteria keep growing, even when antibiotics are used. This problem is seen most often in hospitals and nursing homes.
New antibiotics are created to work against some resistant bacteria. But there are now bacteria that no known antibiotic can kill. Infections with such bacteria are dangerous. Because of this, antibiotic resistance has become a major health concern.
Antibiotic overuse is a main cause of antibiotic resistance. This occurs in both humans and animals. Certain practices increase the risk of resistant bacteria:
Antibiotic resistance causes a number of problems:
Antibiotic resistance can spread from person to person or from animals to humans.
In people, it may spread from:
Antibiotic resistant bacteria may spread from animals to humans through:
To prevent antibiotic resistance from spreading:
Centers for Disease Control and Prevention website. Antimicrobial resistance. www.cdc.gov/drugresistance/index.html. Updated December 17, 2021. Accessed September 6, 2022.
Opal SM, Pop-Vicas A. Molecular mechanisms of antibiotic resistance in bacteria. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 18.
BACK TO TOPReview Date: 4/9/2022
Reviewed By: Jatin M. Vyas, MD, PhD, Associate Professor in Medicine, Harvard Medical School; Associate in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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