Osterhaus experienced a number of changes that were to make him even more visible than before. An important change in this respect is that of occupational context. In 1994, he left the RIVM, 'the institute that muzzled him' (Osterhaus 29 July 2008), when he refused to end his seal research (NRC Handelsblad 14 April 2003) . He and his staff moved to the Erasmus Medical Centre in Rotterdam, where he still holds a position.