Induction of Immunity Against Measles in Pediatric Liver Transplant Recipients

Eligible children in Group 2 will receive a standard dose (0.5 ml) of MMR vaccine during the first medical visit (V1). The lot number and the expiration date will both be recorded on the patient's case report form (CRF). A serological evaluation 4-8 weeks after MMR will identify children requiring an additional dose given 1-2 months apart, as currently recommended for subjects 1 year-old or with limited immune competence (i.e. HIV-infected children). Serological evaluation 4-8 weeks after the second dose or at the one-year follow-up will identify eventual non-responder requiring a third dose. Three will be the maximal number of administrated dose according to this protocol. The persistence of measles-specific antibodies will be assessed yearly, when patients come for their routine visit to the transplant center. Children who do not need MMR immunization because of protective levels will be monitored yearly for maintenance of antibody levels during routine yearly visits/ blood samplings and will not have further intervention.