Infectious and parasitic diseases in the French West Indies, and even more so in French Guiana, exhibit characteristics that differ significantly from those in metropolitan France, both in terms of quality—due to the tropical environment and the microorganisms involved—and in terms of quantity, as the burden of these diseases in terms of morbidity and mortality is much higher than it is in metropolitan France. To prioritize major infectious disease issues in the French West Indies and French Guiana region, a written survey, based on the Delphi method, was conducted among a panel of healthcare professionals in the region. The approach used made it possible to quantify the current perception of communicable diseases among healthcare professionals practicing in the French Antilles and French Guiana. The objective of this study was to supplement the usual indicators of mortality and morbidity in order to provide additional guidance for selecting surveillance priorities as well as regional control and prevention programs. The results unequivocally demonstrate the significance of diseases that do not exist in mainland France, such as vector-borne diseases (dengue, malaria, yellow fever), or diseases whose severity and frequency have been overlooked, such as enteric diseases, as well as diseases with specific epidemiological characteristics, such as leptospirosis in the French West Indies or Q fever in French Guiana. Greater consideration by health authorities of this public health issue specific to the Overseas Departments remains essential to enable the establishment in each department of sustainable and responsive systems for epidemiological surveillance and intervention, which are indispensable for effectively combating these diseases. (R.A.)