This surveillance system based on the data of the National Health Insurance is a complementary tool to nonspecific monitoring in Reunion Island. Not only does it ensure the detection of unusual health events but it also allows to quantify a public health impact for major events. It brings information about the recourse to the so-called 'non emergency' cares that will allow public health authorities to implement adapted control measures. The major advantage of this system is its exhaustive data use that ensures a global view on all consultations carried out in the island and to have a denominator to calculate other indicators. 