The Experimental Virology group at the University Medical Center Groningen (The Netherlands) headed by Jolanda Smit focuses on the pathogenesis of the globally most prevalent mosquito-borne viral infections. These include infections triggered by positive-sense single-stranded RNA viruses of the family Flaviviridae such as dengue virus (DENV) and Zika virus (ZIKV), and a member of family Togaviridae – chikungunya virus (CHIKV). The incidence and disease burden of all three viral infections have dramatically increased during the last decades yet there are no specific treatments available to prevent or treat the diseases and no prognostic markers that would predict the development of severe or chronic manifestation of these infections. We aim to unravel the molecular interactions between the virus and the host in order to guide the development of safe and efficacious vaccines and anti-viral drugs. Specifically, we focus on 1) dissecting the cell entry processes of virus particles, 2) the role of immune cells in controlling and exacerbating pathogenesis, 3) unravelling molecular mechanisms, by which viruses hijack or counteract host cell defense mechanisms eg. stress granules and autophagy, 4) development of antiviral strategies.