观察了６９名儿童口服脊髓灰质炎三价糖丸疫苗（ＯＰＶ）的免疫持久性。基础免疫后４年（再免疫前）Ⅰ、Ⅱ、Ⅲ型中和抗体阳性率分别为９１０７％、９４６４％和９４６４％，几何平均滴度倒数（ＧＭＲＴ）分别为１１７９８、１４３９９和７９９３。４周岁再免疫后１个月Ⅰ、Ⅱ、Ⅲ型抗体ＧＭＲＴ分别升至９０４７８、９７４５４和４８７２７。基础免疫后１个月至基础免疫后６年，３个型≥１：１６的抗体保护滴度在９４６４％～１００％。基础免疫后第７、９年３个型≥１：１６的抗体平均保护滴度分别占９２８６％和７０２４％。 The immunopositivity of oral polio vaccine (OPV) administered to 69 children was observed. The positive rates of neutralizing antibodies of type Ⅰ, Ⅱ and Ⅲ were 9107%, 9464% and 9464% respectively at 4 years after pre-immunization (before re-immunization), and the geometric mean titer (GMRT) were The GMRT of type I, II and III antibodies increased to 904.78, 974.54 and 487.27 respectively at 11798,14399 and 7993.4 years after re-immunization. Antibody protection titers of three types ≥1: 16 ranged from 9464% to 100% from 1 month after basic immunization to 6 years after basic immunization. The average protection titers of antibody with 3 types ≥1: 16 in the 7th and 9th year after basal immunization accounted for 9286% and 7024%, respectively.