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Background and Objective: One of the most important routes of hepatitis B virus (HBV) transmission is from asymptomatic carrier mothers to their infants. It has been concluded that over 50% of Iranian carriers have contracted the infection perinatally, making this the most likely route of transmission of HBV in our country. In this study, we assessed the rate of HBV infection in children were born to HBsAg positive mothers that received hepatitis B immunoglobulin (HBIG) and the first dose of vaccine at birth and the second and third of doses of vaccine at 1 and 6 months of age, respectively. Materials and Methods: In this descreptive study, 123 infants born from HBsAg positive mothers assessed and serum sample of these subjects were tested by ELISA technique for detection of HBsAg, Anti-HBs and Anti-HBc markers. Data were then analyzed by the chi-square and fisher exact tests. Results: From 31241 pregnant women with delivery during this 5-years study about 140 (0.45%) of them were HBsAg positive. Children born to these mothers follow-up and 123 serum samples of them tested for serologic markers of HBV infection. HBsAg was found in 0.8% of the children and 91.9% had one or more serologic markers of HBV infection. Protective rate (Anti-HBs positive) and Anti-HBc positive were 82.1% and 8.9% respectively. Conclusion: This study showed that after having focuced on the vertical transmission route for many years, and implementing strategies such as vaccination and HBIG injection to neonates of HBsAg positive mothers, nowadays it seems that we should pay attention to horizontal route of HBV transmission in this area.

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Background and Objective: Hepatitis B vaccination has been conducted in neonates in the routine vaccination in Iran since 1993. This study was carried out to evaluate the serum hepatitis B antibody level in vaccinated children after 14 years in Kashan, Iran. Materials and Methods: This prospetive cohort study was conducted on 200 fourteen-year-old children which were selected via a simple random sampling method in Kashan, Iran drung 2008-09. This subjects were have been vaccined according to the govermental guildline at 0, 2 and 6 months old. Two ml blood specimens were obtained from children and serum hepatitis B surface antibody (anti-HBs) and hepatitis B core antibody (anti-HBc) were determined by ELISA method. Immunity was interpreted as anti-HBs≥10 IU/L. Data were analyzed using SPSS-13, Chi-Square and Fisher’s exat tests. Results: 92% girls and 95% boys, totally 187(93.5%) children had serum anti-HBs≥10 IU/L. Anti-HBc was positive in 3 (3%) girls and 5(5%) boys, totally 8(4%) which all of them had serum anti-HBS≤10 IU/L. No case of positive HBs Ag was detected. Immunity was detected in 11 of 18 (61.1%) children with birth weight<2.5 kg and in 176 of 182 (96.7%) children with birth weight≥2.5 kg (P<0.05). Conclusion: The immunity following the complete series (0, 2, 6 months old) of hepatitis B vaccination remained detectable after 14 years.