Is it possible something as simple as a special cleanser could save a patient from getting a health care-associated infection? The federal Centers for Disease Control and Prevention decided to test the theory. It examined chlorhexidine (CHG), an antimicrobial cleansing agent used primarily to bathe patients hospitalized in the intensive care unit, to see if it could prevent health care–associated infections (HAIs), particularly antibiotic-resistant staph infections, known as MRSAs, or “superbugs.”