ALTERED REACTIVITY TO MEASLES VIRUS - SKIN TEST REACTIVITY AND ANTIBODY RESPONSE TO MEASLES VIRUS ANTIGENS IN RECIPIENTS OF KILLED MEASLES VIRUS VACCINE

Serum antibody response and skin test reactivity to intradermal measles antigens were studied in 3 groups of children who differed in their prior experience with natural measles or measles vaccines. Children who had received killed measles virus vaccine in the past had an almost universal skin test reactivity to killed measles antigen. Almost 2/3 of this group lacked serum antibody prior to intradermal testing; almost all responded to challenge with significant increase in serum antibody. In contrast, children who had measles previously or had been given live measles vaccine had no skin test reactivity and had detectable serum antibody. These data and others cited suggest that delayed hypersensitivity is responsible for the altered reactivity in some recipients of killed measles vaccine. © 1969 The C. V. Mosby Company.