Intestinal carriage rates of C. difficile in healthy adults are low (0% to 3% in American and European populations, according to Sleisenger) however in recent american guidelines this colonisation could be up to 15-30% of healthy population (might be  temporary presence or transit of organism rather than true colonisation). 

However in hospitalised patients (many of them treated with antibiotics ) the   reported colonization rates  are  10% to 21% and this increases to 15%–30% of residents in long-term care facilities. It is worthy of note that there is mounting  concern about the rise of community-associated infections, which now account for 35%–48% of CDI (Clostridioides difficile infection) diagnoses.

Data from the Nationwide Inpatient Sample indicate that Clostridioides difficile prevalence decreased from 10.1 to 8.6 per 1000 hospital discharges between 2016 and 2018 in the US. Overall it is estimated that half a million people suffer from C. diff infection (CDI) in the USA every year.

According to United Kingdom National Statistics, CDI  was a main or contributing cause of death  in 13 per million population in 2001, which massively rose to 83 per million in 2007. These bad numbers urged huge efforts to reduce CDI in hospitals (by infection control, washing hands, isolating infected individuals and screening most diarrhoeas of hospitalised patients) and by 2011 the estimated number of C. difficile-related deaths in the United Kingdom had fallen dramatically to 19 per million population.