2003和2005年东莞市托幼儿童乙型肝炎免疫状况调查

目的了解东莞市托幼儿童乙型肝炎免疫状况,评价防治效果,为制定防治对策提供科学依据。方法采用分层随机抽样方法,2003和2005年分别抽取东莞市五个镇区5所和4所村办幼儿园,每间幼儿园抽取大、中、小班各一个,被抽中班级的儿童均为调查对象,对各调查对象进行乙肝免疫状况调查。结果2003年和2005年,乙肝疫苗接种率分别为61.22%和93.18%,HBsAg携带率分别为1.48%和0.51%,抗-HBs阳性率分别为62.34%和67.42%;在只完成3针基础免疫的儿童中抗-HBs阳性率均较低,分别为57.22%和59.15%,而在有加强免疫史的儿童中,抗-HBs阳性率明显升高,加强了一针的托幼儿童中抗体阳性率分别为81.72%和76.31%,加强了二针或以上的托幼儿童抗体阳性率则分别达90.00%和92.86%;不同年份有相同免疫次数儿童的抗-HBs阳性率差异无显著性意义;抗-HBs阳性率有随免疫次数增加而增高的趋势。结论东莞市托幼儿童乙肝疫苗接种率2005年较2003年明显提高,HBsAg携带率已控制在较低的水平,两年的抗-HBs阳性率差异不显著。抗-HBs阳性率随免疫次数的增加而增高,建议抗-HBs阴性的儿童应进行加强免疫。

Immune State of Hepatitis B Among Preschool-age Children in Dongguan During the Period of 2000～2005

Objective To study the immune state of hepatitis B among preschool age children in the kindergartens of Dongguan,and to evaluate the protective effects after hepatitis B vaccination. Methods Stratified random sampling method was used in this cross-sectional study.Five district kindergartens and 4 village kindergartens were sampled in 2003 and 2005 respectively,3 classes from grade one to grade three were chosen and all of children in these classes were surveyed on the serum markers of hepatitis B by ELISA. Results The positive rate of HBsAg was 1.48% in 2003 and 0.51% in 2005.The total positive rate of anti-HBs was 62.34% in 2003 and 67.42% in 2005.The positive rate of anti-HBs among the children who received only initial vaccination was 57.22% in 2003 and 59.15% in 2005,but the positive rate increased significantly among those who received additional booster vaccination,which were 81.72% in 2003 and 76.31% in 2005,and 90.00% and 92.86% among those who had twice or more booster vaccination.There was no significant difference among those who received immunization in different years,but the positive rate of anti-HBs increased as the times of vaccination increased. Conclusions Among the kindergarten children of Dongguan,the rate of hepatitis B vaccine immunized in 2005 is higher than that in 2003,the positive rate of HBsAg is low,and the total positive rate of anti-HBs shows no statistically significant difference between these two years. The results suggest that it is necessary to have booster immunization in anti-HBs negative children.