Clostridioides difficile

Clostridioides difficile was formerly known as Clostridium difficile and is often called C. difficile or C. diff for short. C. difficile are bacteria/bugs that are normally found in the large intestine (bowel) and C. difficile is the primary cause of antibiotic-associated diarrhoea and C. difficile infection (CDI). 

A small proportion (less than 1 in 20) of the healthy adult population carry a small amount of Clostridioides difficile and don't experience any problem with it. It is kept in check by the normal "good" bacteria of the intestine. However, when you take an antibiotic, some of the "good" bacteria die causing the Clostridioides difficile bacteria to multiply and you may get an infection in your large intestine.

C. difficile infection CIDR events notified 1871 1763 2056 2288 1733
Crude Incidence Rate*/100,000 population 35.7 32.4  38.7  48.4 31.8
C. difficile infection enhanced cases reported  1877  1906  2030  2185  1707 
Rate hospital-acquired** cases/10,000 BDU 2.2  2.2  2.4  2.8  2.3 


C. difficile infection CIDR events notified, 20201733
Crude Incidence Rate*/100,000 population 31.8 
C. difficile infection enhanced cases reported, 2020 1707
Rate hospital-acquired** cases/10,000 BDU 2.3

*New and recurrent events
**New and recurrent cases associated with reporting hospitals

Figure 1. Number of CDI notifications by month and case type in Ireland, 2008-2020

CDI 2018 graph

Figure 2. Quarterly national rate of healthcare-associated CDI in Ireland, 2009-2020

CDI 2018 quarterly graph


Last updated: 1 March 2022