Between 1921 and 1956, French colonial governments organized medical campaigns to treat and prevent sleeping sickness. Villagers were forcibly examined and injected with medications with severe, sometimes fatal, side effects. We digitized 30 years of archival records to document the locations of campaign visits at a granular geographic level for five central African countries. We find that greater campaign exposure reduces vaccination rates and trust in medicine, as measured by willingness to consent to a blood test. We examine relevance for present-day health initiatives; World Bank projects in the health sector are less successful in areas with greater exposure. (JEL F54, I12, I15, I18, N37, N47, Z13)