Hemagglutination inhibition antibodies in congenital rubella syndrome. A 17-year follow-up in the Ryukyu Islands

K. Ueda, K. Tokugawa, J. Fukushige, H. Yoshikawa and S. Nonaka

We studied long-term rubella hemagglutination inhibition (HI) antibody titers in 381 children born between 1965 and 1966 with congenital rubella syndrome and in 344 of their mothers, who had had postnatally acquired rubella infection. Serum specimens were obtained 12 times during a 17-year period. The initial geometric mean titer of the rubella HI antibody was higher in the children than in their mothers, but the titer declined more rapidly in the children. After 17 years it was 2(5.4) in the children and 2(6.9) in the mothers. In 13 (3.4%) of the children, the rubella HI antibody titer reverted to negativity after three to 17 years. None of the mothers showed a reversion.