Aerosol and subcutaneous measles vaccine: measles antibody responses 6 years after re-vaccination.

There are no large-scale data on the long-term persistence of measles antibody after vaccination by the aerosol route. We therefore followed-up South African schoolchildren 6 years after their re-vaccination with Edmonston-Zagreb (EZ) and Schwarz (SW) measles vaccine given by aerosol and subcutaneous routes. Measles antibody levels and the proportion of children who were seropositive at year 6 remained significantly higher in the Edmonston-Zagreb aerosol group compared to the groups that received Schwarz or Edmonston-Zagreb vaccine subcutaneously. Measles re-vaccination by aerosol evokes a stronger and much longer lasting antibody response than injected vaccine and should thus provide more durable protection against measles.