Induction of cellular and humoral immunity after aerosol or subcutaneous administration of Edmonston-Zagreb measles vaccine as a primary dose to 12-month-old children

Infants were immunized by aerosol (10(3.6) plaque-forming units pfu]/dose) or subcutaneous (sc) (10(4.27) pfu/dose) administration of Edmonston-Zagreb measles vaccine. Measles-specific T cell proliferative responses with a stimulation index of > or =3 developed in 72% of children given aerosol-administered vaccine, compared with 87% given s.c.-administered vaccine (P =.06). Seroconversion rates were 90% after aerosol-administered vaccine and 100% after s.c.-administered vaccine (P=.01), and measles geometric mean titers were 237 milli-international units (mIU) (95% confidence interval CI], 146-385 mIU) and 487 mIU (95% CI, 390-609 mIU) in each group, respectively (P=.01). Measles-specific T and B cell responses were weaker after aerosol than after sc vaccination, indicating a need to use a higher aerosol dose to achieve optimal immunogenicity.