In the early 2000s, hospitals across Australia began installing more hand-sanitizer dispensers in their rooms and hallways for staff, visitors and patients to use. Research showed these alcohol-based disinfectants helped battle staph infections in patients and certain kinds of drug-resistant bacteria. And rates of these infections went down.

But other infections didn’t drop when people started using the sanitizer stations. In fact, certain infections went up. Continue reading at NPR.