Clostridium difficile infection (CDI) was discovered in 1978 as an important cause of antibiotic-associated diarrhoea. CDI became the most common healthcare-associated infection in Northern-America... Show moreClostridium difficile infection (CDI) was discovered in 1978 as an important cause of antibiotic-associated diarrhoea. CDI became the most common healthcare-associated infection in Northern-America and Europe during the antibiotic era, especially after global spread of a fluoroquinoloneresistant ribotype 027 strain in 2003. The rise of CDI urged the use of epidemiological surveillance systems to monitor disease dynamics and rapidly detect outbreaks. However, valid estimations of the infection burden of CDI in Europe were hampered by the heterogeneity and insufficiency of diagnostic algorithms for CDI, lack of standardised typing systems and incomplete surveillance methodologies. This thesis includes two studies conducted within a project named ‘the European CDI Surveillance Network’ focussing on enhancement of CDI surveillance and laboratory capacity for CDI in Europe. In the Netherlands, a sentinel surveillance system monitors the incidence of CDI in hospitals. This thesis describes (spatial) trends in the epidemiology of CDI in the Netherlands, in particular for children and the potentially zoonotic C. difficile ribotype 078. Data of a community-based case-control study was used to apply spatial scan statistics to detect CDI clustering beyond the hospital setting. Finally, this thesis provides directions for future epidemiological surveillance systems of CDI, both in the Netherlands and Europe. Show less
Surgical site infections (SSI) are the most-common healthcare-associated infections among surgical patients and have severe adverse consequences. Surveillance is the ongoing systematic collection,... Show moreSurgical site infections (SSI) are the most-common healthcare-associated infections among surgical patients and have severe adverse consequences. Surveillance is the ongoing systematic collection, analysis, interpretation, and feedback of data, and has been accepted worldwide as a primary step toward prevention of healthcare-associated infections. In the Netherlands, a national network for the surveillance of healthcare-associated infections was set up in 1996 and called PREZIES (__PREventie van ZIEkenhuisinfecties door Surveillance__). In this thesis, the quality of the SSI surveillance within this network is evaluated. The method for postdischarge surveillance recommended by PREZIES seemed feasible and effective, and the mandatory validation visits ensured reliability and robustness of the surveillance data. Furthermore, the predictive power of the NNIS risk index was sufficient for several surgical procedures and could not be significantly improved by using other procedure-specific determinants. Analysis of the time-trend in SSI rates for five surgical procedures showed encouraging decreasing trends, although mostly not statistically significant. Comparison of the Dutch and German SSI surveillance data revealed that even though similar infection surveillance protocols were used, differences occurred in the implementation which hampered the comparison of SSI rates. Additionally, PREZIES contributed to a multi-center intervention project to improve the quality of surgical prophylaxis. Show less