Evaluation of live attenuated measles vaccines prepared in human diploid cells for reimmunization.

Two live attenuated measles vaccines developed in baby calf kidney cells, a similar vaccine produced in chick embryo chorioallantoic cells and five vaccines prepared from human diploid cells (HDC) have been studied by subcutaneous injection in groups of susceptible and immune children in three field trials. The results indicated that the vaccine developed in chick embryo cells which caused mild clinical reactions, had induced a lower seroprotection rate in susceptible children and only a low rise in hemagglutination-inhibition (HI) antibody titre in previously immunized children. The serological responses induced by vaccines developed in HDC or in calf kidney cells were satisfactory in both susceptible and immune children. The superiority of HDC grown measles vaccine for revaccination is discussed.