Epidemiology and diagnosis of acute hepatitis C virus infection

In several studies presented in this thesis, epidemiological and molecular approaches were combined to gain insight into possible linkage between HCV infections. This gives an extra dimension to the outcomes measured in our studies, as the phylogenetic profile of the HCV infections could be added to the analyses. Other studies included longitudinal data from observational cohorts, in which incident HCV (re)infection and possible predictors for HCV infection could be evaluated. Blood samples collected during multiple cross-sectional studies were used to evaluate the utility of an HCV antigen test for screening purposes. The studies in this thesis were initiated with the ultimate goal to increase our understanding of primary and recurrent acute HCV infection among two risk groups in the Netherlands: PWID and HIV-infected MSM. The results of these studies in particular may contribute to improved prevention programs, and may inform clinical decision making and testing policies (e.g., whom to test, and which test(s) should be used).
In part I the current state of the HCV epidemic among MSM and PWID is illustrated. Part II focuses on sexual transmission of HCV among HIV-infected MSM. Part III describes the possible use of assays for screening and diagnosis of acute HCV (re) infection in various settings.
Finally, chapter 10 discusses the main findings of this thesis, relates these to recent literature, and gives recommendations for future studies.