RESPONSE TO MEASLES, MUMPS AND RUBELLA VACCINE IN PEDIATRIC BONE-MARROW TRANSPLANT RECIPIENTS

Bone marrow transplant (BMT) recipients are routinely reimmmunized wit h the childhood vaccine series after transplantation excluding the liv e attenuated vaccines, In this study, the clinical and serologic respo nses to measles, mumps and rubella (MMR) vaccine in children after BMT was assessed, Twenty-two BMT recipients were vaccinated with MMR LT ( MSD), All were at least 2 years post-BMT and without GVHD, Their under lying conditions were leukemia (11), aplastic or Fanconi's anemia (7), thalassemia (3) and metabolic disease (1), All were allogeneic transp lants with matched related donors, The mean age at transplantation was 6.9 years, There were no reported adverse effects of the vaccination, Antibody status for MMR was determined using commercial assays (IFA a nd ELISA) on paired specimens, The mean interval between transplantati on and vaccination was 48 months, Pre-vaccination, no BMT recipient wa s sere-positive for all three, but 23% were positive for measles, 31% for mumps and 14% for rubella, Post-vaccination, 68% of BMT recipients were sere-positive for all three, with 77% for measles, 87% for mumps and 91% for rubella, Therefore, MMR vaccination at 2 years or later a fter BMT in paediatric recipients without GVHD was safe and significan tly increased the proportion sere-positive for MMR.