As a contribution to the existing literature on deliberate or unintended neglect, concealment and ignorance regarding significant and enduring public health problems-produced by economic marginality, lack of political power and institutional failures affecting specific places and groups-this article discusses the history of epidemic sleeping sickness and endemic onchocerciasis in colonial northern Ghana from 1909 to 1957. Despite accumulating evidence of their serious impacts on the health of northern communities, and calls to action on the part of some health officials, both diseases were only officially recognised as significant risks when it was no longer politically possible to deny them. The particular histories of each disease, in the same region over the same decades, reveal two comparable and interrelated trajectories of neglect.