Introduction
In Finland, incidence of CDI increased during 2002-2006, shown by the population-based analysis of hospital discharge diagnoses, a trend similar to that in the US. In 2008, toxin-positive C. difficile became a notifiable disease. During the first 3 years of surveillance, the annual incidence decreased from 111 to 90/100,000 population, but rose up to 100 in 2011. The epidemic situation and trends differed regionally. Both PPI and FQ use have been associated with increased risk of CDI.