Multicenter Pilot Study Evaluating the Immunogenicity of an Innovative Pneumococcal Vaccination Strategy in Splenectomized Adults

Inclusion Criteria: * Age ≥ 18 years and ≤ 75 years * Splenectomized since at least 2 weeks, with Howell-Jolly bodies on a blood smear and ultrasonographic confirmation * No immunosppressived conditions : mainly trauma , idiopathic thrombocytopathic purpura or autoimmune hemolytic anemia, with no active treatment * Available for 37 months of follow-up starting from the screening visit * Contraception that the investigator judges effective for the first 2 months of the trial, with a negative pregnancy test * Women not planning to become pregnant in the 6 months following inclusion (M0) * Signed informed consent Exclusion Criteria: * Pregnancy or planned pregnancy in the 2 months following inclusion (M0) * Pathology or conditions which modify immune response (excluding splenectomy) : HIV infection, immunosuppressive therapy ongoing or in 6 months before inclusion (M0), including corticosteroids \> 10 mg daily, topic inhaled or dermic corticoid treatments are allowed, hematopoietic stem cell allo / autograft, primary immune deficiency, nephrotic syndrome, sickle cell disease, evolutive neoplasia * History of anaphylactic reaction following vaccination * Known allergy to any of the ingredients of the vaccines: aluminium phosphate, phenol, Corynebacterium diphtheriae CRM-197 protein * Previous vaccination with 7-valent or 13-valent pneumococcal conjugate vaccine (in the 5 last years) * Previous vaccination with the pneumococcal polysaccharidic vaccine in the 3 years before incl…