Abstract

Hepatitis B seroprotection in children age 10-15 years old after completed basic hepatitis B immunization

Novie Homenta Rampengan,1 Mulya Rahma Karyanti,2 Sri Rezeki Hadinegoro2

1. Departement Child Health, Faculty of Medicine Sam Ratulangi University/Prof. R.D. Kandou General Hospital, Manado

2. Departement Child Health Faculty of Medicine Indonesia University/Cipto Mangunkusumo General Hospital

Background. Prevalence of hepatitis B viral (HBV) infection in Indonesia is still high with average of 9.4%. Those related to HBV infection during the early life, especially through vertical transmission from mother to her baby. Data in Indonesia showed the proportion of vertical transmission 45.9% and 5.2% pregnant women who have HBeAg positive. The most effective way to control HBV infection is by immunization HB. On the other hand many studies reported anti-HBs seroprotection has been declined at the age more than ten years but other studies reported controversial. In addition there are suggested many factors that can influence anti-HBs titer.

Objective. To measure anti-HBs titer and to find any factors which influence anti-HBs titer.

Method. Analitic observational study with cross sectional design was conducted in children 10-15 years of age from ten school at Tuminting district, Manado city, on October-November 2014. By stratified random sampling 105 children selected as research subject. Data analysis done by SPSS 22.

Results. Among 48 schools, selected 10 schools with 105 children but only 23 (21.9%) children who have anti HB antibody (21,9%). Seventy six (72.4%) subjects were female, 78 (74.3%) subjects with good nutrition status and 98 (93.3%) subjects had ≥2,500 grams birth weight. Data from the immunization record book 26 (24.8%) subjects showed HB-1 vaccination done at ≤7 days of age and 45 (42.9%) subjects have interval between HB-2 and HB-3 were ≥2 months. Data from mother were highest age 86 (81.9%) was 20-35 years old, 64 (60.9%) graduated from high school and 79 (75.2%) of parents had income ≥2 million Rupiah per month. Multivariate analysis obtained that administration of HB-1 ≤7 days (p=0.02) and interval between HB-2 and HB-3 ≥2 months (p<0.001) had important role in anti HB seroprotection in children.

Conclusion. This study found low proportion number of anti HB titer (21.9%). Factors of administration of HB-1 ≤7 days and interval between administration of HB-2 and HB ≥2 months had important role in anti HB seroprotection in children age 10-15 years old.

Keyword: Seroprotection, anti-HBs titer, factors influenced anti-HBs titer