What is C. diff?

  • Clostridioides difficile (klos–TRID–e–OY-dees dif–uh–SEEL), or C. diff, is a Gram-positive, spore-forming bacterium or germ.
  • C. diff may colonize the human colon. It is present in 2-5% of the population.
  • C. diff is found throughout the environment in soil, air, water, human and animal feces, and in contaminated food products.
  • This bacterium can lead to an infection in the colon called Clostridioides difficile infection, or CDI.
  • Symptoms of CDI may include watery diarrhea (known as Clostridioides difficile-associated diarrhea, or CDAD), fever, nausea, abdominal cramping, dehydration, and loss of appetite. Learn more: Why Should I Care?



  • C. diff is the most common cause of infectious diarrhea in healthcare settings.
  • C. diff caused nearly 500,000 infections in one year, and 29,000 deaths.
  • CDI accounts for significant rates of illness and death. In 2011, C. difficile was the 17th leading cause of death for people aged 65 years and older.
  • CDI is being increasingly recognized as a cause of diarrhea in the general community and in populations without the traditional risk factors for CDI
  • CDI recurs in about 1 in 5 patients. Learn more here: Why Should I Care?


Risk Factors

  • Current or recent antibiotic use. Taking antibiotics increases the risk for acquiring a CDI by 7 – 10 times
  • Being aged 65 or older
  • Admission to the hospital for more than 8 hours, especially if admitted through the hospital emergency room
  • Admission to the intensive care unit
  • Residency in a nursing home
  • Other risk factors include using antacids and gastrointestinal surgery
  • Learn more by downloading our Care Guide.

If you suspect you or a loved one has a CDI, please visit our For Patients & Families page



  • Only take antibiotics as prescribed by your doctor when absolutely needed for an infection.
  • You can help prevent the spread of C. diff in many ways, including thoroughly washing your hands, using bleach-based cleaners, and using prescriptions exactly as directed.
  • Learn more by downloading our Care Guide.