The bacteria, C. difficile, is typically found in hospitals, but a study out Wednesday reports a substantial number of people contracted the bug who hadn't been in a hospital, but had recently visited the doctor or dentist.
The bacteria can cause deadly diarrhea, according to the CDC, with infections on the rise. The new report shows nearly half a million Americans infected in various locations in one year, with 15,000 deaths directly attributed to C. diff.
In a 2013 study, researchers found C. diff present in six out of seven outpatient clinics tested in Ohio, including on patients' chairs and examining tables.
The CDC is so concerned that they're starting a new study to try to assess nationally whether people are getting C. diff in doctors' offices.
"This is really an important issue. We need to understand better how people are getting C. diff," said Dr. Cliff McDonald, a medical epidemiologist at the CDC.
In the meantime, patients should wash their hands after visiting the doctor's office -- with soap and water, because alcohol-based gels don't get rid of C.diff.
Another tip: Question your doctor whenever you're prescribed an antibiotic. Powerful broad-spectrum antibiotics wipe away good bacteria in your gut that fight off the bad bacteria, which leads the way to C. diff.
Johns Hopkins safety expert Dr. Peter Pronovost recommends asking your doctor if you really need an antibiotic, if there's a less powerful one that will treat your infection, and if you're being prescribed the antibiotic for the shortest time possible.
The CDC study, published Wednesday in The New England Journal of Medicine, said 150,000 people who had not been in the hospital came down with C. diff in 2011. Of those, 82% had visited a doctor's or dentist's office in the 12 weeks before their diagnosis.
The CDC is hoping its new study will help determine cause and effect, because it's possible the patients had C. diff to begin with and went to the doctor to get help. It's also possible that antibiotics prescribed during the doctor's visit, and not microbes at the doctor's office, caused the infection.