广州市青少年学生乙型肝炎病毒感染状况及危险因素调查

目的了解推广使用乙型肝炎疫苗后,广州市青少年学生乙型肝炎病毒感染状况和感染危险因素。方法选取广州市29所中学的初一和高一学生共14744人作为调查对象,检测乙型肝炎表面抗原（HBsAg）和抗体（抗-FiBs）,HBsAg与抗-HBs同时阳性者作乙型肝炎病毒S基因扩增和DNA序列分析。以统一的问卷对HBsAg阳性者进行流行病学调查。结果检出HBsAg阳性者424人,阳性率为2．9％。抗-HBs阳性者12201人,阳性率为82.8％。4人HBsAg、抗-HBs同时阳性,其中1人S基因“a”决定族第126位的异亮氨酸（ATT）变为苏氨酸（ACT）,第143位由丝氨酸（TCG）变为苏氨酸（ACG）,第145位由甘氨酸（GGA）变为精氨酸（AGA）,另外3人未检出S基因“a”决定簇氨基酸变异。流行病学调查提示部分学生问卷可能通过母婴传播以及日常生活密切接触感乙型肝炎病毒。结论乙型肝炎疫苗是预防乙型肝炎的有效制荆。病毒S基因“a”决定簇变异可使乙型肝炎疫苗保护失败,但目前的发生率较低,无须改变疫苗的制备及免疫策略。

Hepatitis B virus infection and its risk factors among adolescents in Guangzhou

Objective To find out hepatitis B virus infection and its risk factors among adolescents in Guangzhou after hepatitis B vaccine was widely applied.Methods A total of 14744 students at grade 1 and 4 of 29 high schools in Guangzhou were recruited into the study.HBsAg and anti-HBs were tested.Hepatitis B virus S gene derived from persons with concurrent HBsAg and anti-HBs was amplified by polymerase chain reaction and sequenced directly.Epidemiology investigation was carried out among persons with positive HBsAg with a standardized questionnaire. Results A total of 424 persons(2.9%) were HBsAg positive and 12 201 persons(82.8%) were anti-HBs positive.S gene "a" determinant mutation was identified in 1 of the 4 persons with concurrent HBsAg and anti-HBs,i.e. isoleucine-to-threonine at codon 126,serine-to-threonine at codon 143,and glycine-to-arginine at codon 145.No S gene "a" determinant mutation was identified in the other 3 persons.Epidemiology investigation revealed that some students might be infected via mother-to-infant transmission or close contacts in daily life. Conclusions Hepatitis B vaccine is an effective agent for the prevention of hepatitis B.S gene "a" determinant mutation could be related to the failure of hepatitis B vaccine protection.At present such mutation rate remains low and there is no need to alter the preparation and immunization strategy of hepatitis B vaccine.