Measles Vaccine

Clinical and serological observations have been made on 103 children who received an attenuated strain of live measles virus. The vaccine was prepared from the Edmonston strain of Enders, propagated in tissue cultures of chick embryo. Safety tests were carried out in rabbits, mice, and guinea pigs. Antibody responses were determined by 2 methods, one involving the cytopathogenic effect of mixtures of virus with serum, the other involving a metabolic inhibition test. In 10 children the fever and malaise were like those of mild measles; the other children carried on as usual. No secondary cases were found. Of the 88 children who had been nonimmune, the 86 who could be followed gave serological evidence of immunization similar to that following ordinary measles. Complications were rare, and the vaccine was generally accepted by parents and physicians.