With rising numbers of COVID-19 positive patients in March 2020, Norwegian municipalities, who are responsible for contact tracing, struggled to register all the infected and their close contacts. This was partly due to the scale of the pandemic and partly because the only tools they had were pen and paper and in some cases spreadsheets. To address this situation, some municipalities started exploring how digital health information systems could support them in handling the rapidly changing and unforeseen complexity of the COVID-19 contact tracing work. Drawing on an ongoing case study of disease surveillance in Norway, we first explain how contact-tracing work has undergone a rapid digital transformation. Then we offer an institutional analysis by using a perspective of institutional work forms to illuminate how the digital transformation has brought about long term institutional changes. We then argue that we have seen an institutionalization of digital contact tracing while manual contact tracing is still ongoing. Thus, both the new and the old institution stay alive and are central for different purposes. With this paper, we are contributing to research on digital transformation by theorizing how technology and more particularly digital transformations are intertwined with institutional change. We further contribute to research on institutional work by illustrating how this is a relevant lens to understand digital transformations.