In the summer of 2015, soldiers of the 3rd Foreign Infantry Regiment and civilian scientists mounted a joint expedition on foot to reconnoiter and better define the southern frontier of French Guiana with Brazil. Three doctor-nurse pairs worked in relay to provide medical support for this unprecedented 42-day, 320-km journey through a hostile and isolated environment, a mission whose success was made possible by large-scale logistic and technical prowess. The army health department, using knowledge gained from previous large-scale missions and expeditions and from its staff's local experience, provided its technical support for personnel selection, organization of the health logistics, and field support. This article describes the difficulties encountered from a medical perspective, the diseases encountered, and the final assessments of the personnel who completed this expedition.
Keywords: French Guiana; expedition; foreign legion; military medicine; tropical forest.