Current status of Clostridium difficile infection epidemiology

Abstract

The dramatic changes in the epidemiology of Clostridium difficile infection (CDI) during recent years, with increases in incidence and severity of disease in several countries, have made CDI a global public health challenge. Increases in CDI incidence have been largely attributed to the emergence of a previously rare and more virulent strain, BI/NAP1/027. Increased toxin production and high-level resistance to fluoroquinolones have made this strain a very successful pathogen in healthcare settings. In addition, populations previously thought to be at low risk are now being identified as having severe CDI. Recent genetic analysis suggests that C. difficile has a highly fluid genome with multiple mechanisms to modify its content and functionality, which can make C. difficile adaptable to environmental changes and potentially lead to the emergence of more virulent strains. In the face of these changes in the epidemiology and microbiology of CDI, surveillance systems are necessary to monitor trends and inform public health actions.

Figure 1.

Discharge rate for Clostridium difficile infection from US short-stay hospitals by age [22]. Abbreviation: CDI, Clostridium difficile infection.

Figure 2.

Incidence of Clostridium difficile infection per 1000 hospitalizations by age (Healthcare Utilization Project Kids’ and Inpatient Database, United States, 1997–2006). Modified from Zilberberg et al [28]. Abbreviation: CDI, Clostridium difficile infection.