RT Journal A1 DUDGEON J T1 RUbella vaccination-reply JF American Journal of Diseases of Children JO American Journal of Diseases of Children YR 1979 FD November 1 VO 133 IS 11 SP 1203 OP 1203 DO 10.1001/archpedi.1979.02130110110028 UL http://dx.doi.org/10.1001/archpedi.1979.02130110110028 AB In Reply.—I agree with Preblud and his colleagues that the most effective way of evaluating the immune status of the girls who seem to be seronegative is by revaccination and subsequent serological retest. This should not be too difficult in practice. I regret that1 I did not refer to the valuable studies of Weibel et al2 and others3 on the persistence of antibody after vaccination. These are distinctly encouraging, but nevertheless, in my opinion, long-term surveillance along the lines carried out by Krugman4 in respect of measles vaccine is necessary to determine the duration of immunity after early childhood immunization with rubella vaccines.