Monitoring of Measles-specific Immune Status in Adult Allogeneic Hematopoietic Stem Cell Transplant Recipients

"For the study population (allo-HSCT recipients): 4 visits with biological sampling (blood and oral fluid) at each visit:~* Visit V1 (inclusion visit = D1): immediately before the first dose of MMR (dose-1),~* Visit V2 (D1 + 35 (+/-7) days): immediately before the second dose of MMR (dose-2)~* Visit V3 (D1 + 70 (+/-14) days)~* Visit V4 (D1 + 365 (+/-90) days) For healthy volunteers: a single visit (V1) with biological sampling (blood and oral fluid)"