( CNN ) The Centers for Disease Control is raising a red flag that a potentially deadly bacteria may be lurking in your doctor 's office . The bacteria , C. difficile , is typically found in hospitals , but a study out Wednesday reports a substantial number of people contracted the bug who had n'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 do n'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 . CNN 's Sandee LaMotte contributed to this report .
C. tuberculosis , is typically found in hospitals , but a study finds resistance to doctor , dentist visits . The fungus can cause deadly infections , according to the CDC , with infections on the rise .