Antibody Levels After Hepatitis B Vaccination Among 1–5-Year-Old Children in Bandar Abbas, South of Iran

Background: Hepatitis B infection is a global challenge. There are currently more than 500 million morbidities and one million mortalities due to complications annually. Considering that vaccination is the only way of prevention, this study was designed to evaluate the efficacy of the hepatitis B vaccine and measure antibody (Ab) titers in vaccinated children aged 1–5 years. Methods: Two hundred and thirty-three children aged 1–5 years referred to Bandar Abbas Children’s Hospital in 2020 were enrolled in this cross-sectional descriptive study. The required data, including the Ab titer, gender, breastfeeding, exposure to cigarette smoke, and residence (city or village), were collected using a checklist. Then, they were entered into SPSS 22 and evaluated using chi-square and Mann-Whitney statistical tests. Results: Of 233 patients, 185 (79.4%) had positive Ab titers. Accordingly, the immunogenicity of the hepatitis B vaccine was 79.4%. There was a significant correlation between age and Ab titers (P<0.05). However, no significant relationship was found between gender, place of residence, breastfeeding, and exposure to cigarette smoke and Ab titers (P>0.05). Conclusion: Overall, the rate of positive response to the hepatitis B vaccine was in the range of previous studies (69–95%). Although the hepatitis B vaccine was effective in children aged 1–5 years who were referred to Bandar Abbas Children’s Hospital, there is a possible need for continuous surveillance and a booster vaccine