健康儿童连续三批次国产甲型肝炎灭活疫苗接种的免疫持久性研究

Study on the Immune Persistence of Three Consecutive Lots of Domestic Inactivated Hepatitis A for Healthy Children

目的评价连续三批次国产甲型肝炎(甲肝)灭活疫苗(Hepatitis A Vaccine,Inactivated;HepA-I)的免疫持久性。方法 采用开放式设对照的临床研究设计,试验疫苗使用连续三批次国产HepA-I,选取进口HepA-I做对照,其中国产HepA-I的剂量为每支250单位(Unit,U)/0.5毫升(ml),进口HepA-I的剂量为每支720酶联免疫吸附试验单位[Enzyme Linked Immunosorbent Assay(ELISA)Unit,Elu]/0.5ml。受试者为入选前期连续三批临床试验并完成全程免疫的2～8岁健康儿童,在完成0、6个月免疫程序接种后的1年、2年和3年,采血检测抗甲肝病毒抗体(Antibody to Hepatitis A Virus,Anti-HAV)。结果受试者共计344人,在完成全程免疫后的第3年,四个试验组Anti-HAV阳性率差异无统计学意义(精确概率法,P=0.245),国产HepA-I三个批次组受试者Anti-HAV的几何平均浓度(Geometric Mean Concentration,GMC)为295.6毫国际单位(mIU)/ml～440.0mIU/ml,进口HepA-I受试者的GMC为234.3mIU/ml,差异有统计学意义(F=2.838,P=0.005)。结论国产HepA-I在全程免疫接种后的免疫持久性良好。

Objective To evaluate the immune persistence and consistency of three consecutive lots of an inactivated hepatitis A vaccine. Methods An open, controlled clinical trial was conducted in 344 healthy children aged from 2 to 8 years who completed two doses of full immunization of hepatitis A vaccine in the previous clinical research. The dosage of domestic trail vaccine was 250 Unit （U）/0.Sml per dose and the imported control＇ s was 720 enzyme linked immunosorbent assay （ELISA） Unit （Elu）/ 0.Sml per dose. Antibodies to hepatitis A virus （Anti-HAV） titers were determined after 1, 2 and 3 years of full immunization. Results After 3 years of full vaccination, the seroconversion rate of four groups showed no significantly difference among 344 children （ Fisher exact test, P=0.245 ）. The geometric mean eoncentration （GMC） of three lots of domestic vaccine were 295.6 mIU/ml-440.0mIU/ml and the GMC of control vaccine was 234.3 mIU/ml, the GMC of each lot of domestic vaccine was higher than the imported control vaccine＇ s and the differences were statistically significant （F =2.838, P =0.005 ）. Conclusion The domestic trail vaccine had a persistent immunogenicity which could developed a long-term protection after two doses of full immunization among children.