| Abstract: | Objective In order to observe the erricacy of low-dose in the third injection of hepatitis B vaccine.Methods 126 children aged 5~9 years were enrolled in a double-blind, place-controlled and randomized field trial.They were randomly divided into log and 2og dose group, and were redivided into 2g, 5g, 1og, 2og or non-in-Jected subgroups when the. third booster injections were given. Results During the 9 years follow-up, the differences of tke anti-HBs levels (GMT) among the groups were not significant at every time (P>o. o5). The GMTs at the ninth year(T1o8) were 7. o, 6. 4, 9. 9, 6. 1, 9. 7, 5. 4 and 7. 4, respectively (P > o. o5). The HBV infection rates among the groups had no significant difference (P > o. o5). The protective rates in the groups were all higher than 75% at T1o8.Conclusion According to the data, it can be concluded that the third injection with low-dose has no influence on the vaccine efficacy(either short-term or long-term efrlcacy). |
