Antimicrobial Resistance

Antimicrobial resistance enables microbes to avoid or diminish the effects of antimicrobial agents and is acquired either through mutation or the acquisition of resistance genes. Antimicrobial-resistant organisms can cause infections that are difficult to treat, often requiring the use of expensive, less effective, or more toxic alternative medications (www.cdc.gov/drugresistance/about.html). Resistance can occur in viral, bacterial, fungal, and parasitic pathogens. The epidemiology of resistant organisms often varies globally from that seen in the United States. Travelers and medical professionals should be aware of the risk of acquisition of resistant organisms during international travel and consider travel history when caring for patients, both to identify effective treatment for infections and to ensure infection control interventions are in place to prevent spread of antimicrobial resistance.

The focus of this section is on resistant bacteria and an emerging fungal pathogen; neither are covered in pathogen-specific chapters. These microbes can be acquired both from health care and community exposures during international travel, causing illness or asymptomatic colonization. Additional information about organism-specific resistance can be found in the disease specific sections of Chapter 4, Travel-Related Infectious Diseases, and in Chapter 9, Medical Tourism.