乙型肝炎疫苗长期免疫对人群乙型肝炎病毒流行状况的影响

目的探讨乙型肝炎（乙肝）疫苗长期免疫接种后整体人群乙肝病毒（HBV）感染状况及其变化趋势。方法采用整群抽样结合横断面调查方法，共收集资料完整的调查对象4686名，采集静脉血并分离血清，用固相放射免疫法检测HBV感染标志。结果整体人群平均HBsAg阳性率为7．5％，抗-HBs为44．5％，抗-HBc为47．8％；0～19岁人群HBsAg和抗-HBc阳性率较≥20岁人群显著下降。乙肝疫苗免疫组的HBsAg阳性率为2．8％，抗-HBc阳性率为12．0％，HBV感染率为12．5％，未免疫组分别为10．2％、69．8％和71．2％。男性平均HBsAg阳性率比女性高，抗-HBc和抗-HBs阳性率男女性别间无差异。0～19岁人群的HBsAg阳性率为2．4％，而20～30岁人群阳性率达到13．6％～17．7％，到60岁开始下降；0～19岁人群的抗-HBs阳性率随年龄增长而明显下降，≥20岁人群的抗-HBs、抗-HBc阳性率均随着年龄增长而呈升高趋势。结论长期开展新生儿乙肝疫苗免疫使人群HBV流行状况发生变化，感染高峰年龄段后移。

Study on the variations of hepatitis B virus status among people having received hepatitis B vaccine

OBJECTIVE: To study the epidemiological pattern and trends of hepatitis B virus (HBV) in the area where people had been immunized by HBV vaccine for long time. METHODS: Through cluster sampling and cross-sectional study, relative information and blood samples from people in Long-an county by families were collected. Signals of HBV infection were tested by solid-phase reverse immunosorbent test. RESULTS: (1) The average HBsAg positive rate was 7.5% with anti-HBs as 44.5 %, and anti-HBc as 47.8%. The positive rates of HBsAg and anti-HBc among 0-19 year-olds were lower than those of > or = 20 year-olds. (2) The positive rates of HBsAg, anti-HBc and HBV infection among HBV vaccine immunized group were 2.8%, 12.0% and 12.5% respectively, comparing with which among the un-immunized group as 10.2%, 69.8% and 71.2% respectively. (3) The HBsAg positive rate of male was higher than the female's but with no significant difference of anti-HBs and anti-HBc between different sexes. (4) The average HBsAg positive rate of 0-19 years old group was only 2.4%, while that of 20-30 years old group was 13.6%-17.7% and dropped from 60 years old group and on. The anti-HBs positive rate of 0-19 years old people started to drop significantly by age. The anti-HBs and anti-HBc positive rates of > or = 20 years people were showing a rising trend by ages. CONCLUSION: It seemed obviously that the HBV epidemiological patterns had changed after HBV vaccine had been universally used for long time in newborns. The age peak of infection had been pushed backward for nearly 20 years. It had been proved that the HBV vaccine immunization program had obtained excellent efficacy.