Five times a quarter of a century at Instituto Oswaldo Cruz

The pathway of Instituto Oswaldo Cruz (IOC) runs parallel with the astonishing series of events in the 20th century, which might be viewed as a dispute between hope and ideological belief. As a centennial organisation the IOC has witnessed the same set of events and perhaps experienced some of them, but in most cases, it has been unable to influence or deter them. Since its beginnings the IOC has been engaged in addressing public health challenges and either by serendipitous findings or by the scientific inquiry it has brought some Res Novae and ignited sparks of hope that one day most of the infectious diseases that proliferate in Brazil might be controlled. In this perspective essay to introduce the series of articles in celebration of the 125th Anniversary of the IOC I will sketch an overview of its journey in the context of some 20th century events through a quarter of a century time frame.