Abstract: The invention concerns the use of an immunogen specific of a pathogenic agent with a gateway in the buccal mucous membrane region, for producing a vaccine composition to be administered in the floor of the mouth in a human being so as to develop directly a local response in IgA antibodies and in B cells secreting IgA in the buccal mucous membrane, saliva and ganglions draining said mucous membrane. The invention also concerns a vaccine composition capable of being applied in the floor of the mouth in a human being to induce local and systemic immunity in IgA antibodies, substantially consisting of a material adhering or not to the buccal mucous membrane and containing an immunogen specific of the pathogenic agent with a gateway into the buccal mucous membrane.