Persistence of maternal antibody in infants beyond 12 months: mechanism of measles vaccine failure.

Journal of Pediatrics (Impact Factor: 3.74). 12/1977; 91(5):715-8. DOI: 10.1016/S0022-3476(77)81021-4
Source: PubMed

ABSTRACT A serologic study was made in 34 children immunized against measles at the age of 12 months. Using a sensitive virus neutralization test, it was found that many of the children had pre-existing maternal antibody to measles virus. Children with high pre-existing antibody titers failed to seroconvert. Children with lower pre-existing antibody titers seroconverted, but the resulting antibody titer was significantly lower than in children without pre-existing antibody titer. The results of this study demonstrate a probably mechanism for measles vaccine failure in 12-month-old children and support the recommendation of the Public Health Service Advisory Committee on Immunization Practices to postpone measles vaccination to 15 months of age.

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