IMMUNOSUPPRESSION AFTER MEASLES VACCINATION

The influence of conventional live attenuated measles vaccine on cellu lar immune responsiveness was investigated in Sweden and Guinea-Bissau . Sixteen children in a residential area in Bissau and 16 living in so uthern Stockholm were examined before and 8-10 days after vaccination. Lymphoproliferation was measured to concanavalin A (con-A), PPD and t etanus toroid (TT) using a whole-blood H-3-thymidine incorporation ass ay. Stimulation indices were significantly lower after vaccination tha n before, in the case of con-A (p = 0.03) and TT (p = 0.01) in the Gui nean children and in the case of PPD (p = 0.009) and TT (p = 0.03) in the Swedish children. Stimulation of lymphocytes from measles-immune c hildren with measles antigens resulted in weak lymphoproliferative res ponses. These observations may be relevant to the increased mortality found in children immunized with high-titre measles vaccines, as compa red to controls, in recent studies. The study confirms the applicabili ty and usefulness under field conditions of the whole blood version of the thymidine incorporation assay.