Study On The Status Of HBV Infection, Its Relative Factors And Immune Persistence Of Hepatitis B Vaccine

Objective:To evaluate vaccination status of hepatitis B in population aged 1 to 59 years in Tianjin,evaluate distribution status and relative factors of HBV markers;and to observe the level of antibody to hepatitis B surface Antigen in children and youngsters aged 1 to 18 years and immune persistence of hepatitis B vaccine.Methods:In September 2006,1253 subjects aged 1 to 59 years were sampled from population of three streets in city and two small towns in countryside according to PPS sampling method and inquired about their related information by questionnaire, and their venous blood samples were collected to detect HBV infection markers,i.e. HBsAg,Anti-HBs,Anti-HBc,HBeAg,Anti-HBe.Distribution status of HBV markers and vaccination were described,and relative factors of HBV infection were explored.In August to November 2006,971 children and youngsters aged 1 to 18 years were sampled from population of three streets in city and three small towns in countryside according to PPS sampling method and inquired about their related information by questionnaire,and their venous blood samples were collected to detect Anti-HBs;638 subjects inoculated with 5μg recombinant yeast-derived hepatitis B vaccine were analyze for the immunization persistence.The databases were set up by EPI Data 3.1 software;Chi square test for the rate differences in different groups, t-test and F-test for average differences in different groups and non-conditional logistic regression for relative factors of HBV infection were analyzed by SPSS 11.5 software.Results:The rates of HBsAg,Anti-HBs,Anti-HBc positive and HBV infection were 1.52%,47.33%,14.45%and 18.99%respectively,and singular positive rate of Anti-HBs was 27.37%in subjects aged 1 to 59 years.The rates of HBsAg,Anti-HBc positive and HBV infection increased with the increasing of age(P＜0.05).The positive rates of Anti-HBs and singular positive rates of Anti-HBs decreased with the increasing of age(P＜0.05).Coverage of hepatitis B vaccine in subjects aged 1 to 59 years was 49.96%,and the coverages in groups of subjects aged 1 to 4 years,5 to 14 years and 15 to 59 years were 99.65%,81.87%,15.79%respectively.Coverage of hepatitis B vaccine decreased with the increasing of age(x_trend²=623.46,P=0.000). The results of univariate non-conditional logistic regression analysis showed that vaccination of hepatitis B was the protective factor and the age,operation history,oral cavity treatment,endoscope usage,blood transfusion history,traumatic cosmetology history,acupuncture history,history of using syringe with others,and shaving in barber shop were risk factors for HBV infection.The results of multivariate non-conditional logistic regression analysis revealed that vaccination of hepatitis B and age were associated with HBV infection,and other factors were not associated with HBV infection.The positive rate of Anti-HBs in children and youngsters aged 1 to 18 years was 76.41%and GMT was 65.88 mIU/mL.The GMTs of 1～3 years old and 12～14 years old group were higher than other age groups.The GMTs of Anti-HBs on 1～11months, 1 year,2 year,3 year,4 year after inoculating 5μg recombination yeast hepatitis B vaccine were 161.81,152.70,149.38,127.06 and 57.61mIU/mL respectively,and the results revealed that Anti-HBs level began to decline obviously in the fourth year after vaccination,but GMT could maintain effective protective level(10mIU/mL).Conclusions:The rates of HBsAg positive and HBV infection of subjects aged 1 to 59 years were 1.52%and 18.99%respectively,which were lower than the average of all the country and the datas of 1992 and 2002 in Tianjin.The HBsAg,Anti-HBc positive rates and HBV infection rate increased with the increasing of age (P＜0.05).The singular positive rate of Anti-HBs of children below 15 years old was higher than the rate in 2002 all over the country,and the descent trend with the increase of age was accord with former data.Coverage of hepatitis B vaccine degraded gradually with the increase of age.The results of the investigation confirmed that vaccination of hepatitis B could prevent HBV infection effectively, age was the risk factor for HBV infection,and 5μg recombination yeast hepatitis B vaccine had good effects on all children and youngsters.The GMT level of Anti-HBs could maintain effective protective level for 4 years at least,the antibody level began to decline obviously in the fourth year after vaccination.