Assuming the PrEP efficacy of 80% and that 85% of included participants being MSM - the objective is to evidence a decrease of at least 15% of new diagnosis of HIV infections among MSM in Ile-de-France area. This objective is in the framework of a commitment of large cities against AIDS with the political support of the City of Paris for the "Paris sans SIDA" program and the commitment of the Île-de-France area.