PERSISTENCE OF MEASLES ANTIBODY IN ABSENCE OF CIRCULATING NATURAL VIRUS 5 YEARS AFTER IMMUNIZATION OF AN ISOLATED VIRGIN POPULATION WITH EDMONSTON-B VACCINE

Brown, P., D. C. Gajdusek and T. Tsai (National Institute of Neurological Disease, NIH, Bethesda, Md. 20014). Persistence of measles antibody in the absence of circulating natural virus five years after immunization of an isolated virgin population with Edmonston B vaccine. Amer. J. Epid., 1969, 90: 514-518.-In the absence of circulating natural measles virus in an isolated Pacific atoll community after immunization of 136 immimologically virgin individuals from 1 to 24 years of age with Edmonston B strain live attenuated measles vaccine, serum levels of HI antibody remained stable between 1 and 22-Jan years after immunization, but declined 2 to 3-fold by 5 years after immunization. Sera having the highest antibody titers at 1 year showed the greatest decline, with a resultant narrowing of the titer range at 5 years. Individuab with even undetectable HI antibody levels at 5 years nevertheless showed neutralizing antibody at a serum dilution of at least 1: 2, and thus presumably remain immune from infection. © 1969, by THE JOHNS HOPKINS UNIVERSITY.