Study of coverege of immumization against hepatitis B virus in children aged 0-9 years in Mongolia

Abstract

Background: Although it has been thirty years since the introduction of the hepatitis B virus vaccine, Mongolia is still a country with a high prevalence of hepatitis B virus (HBV) infection. Vaccination of infants, especially hepatitis B vaccine within 24 hours of birth, prevents 90.0% to 95.0% of HBV infection and reduces transmission of HBV after 2 consecutive doses. However, studies have been conducted since started national immunization, there is a lack of studies evaluating the coverage of hepatitis B immunization in a representative sample of children aged 0-9 years in Mongolia, which is the reason for conducting this study. Aim: Evaluate coverage of immunization against hepatitis B virus in children aged 0-9 years in Mongolia. Materials and Methods: The study was conducted population-based cross-sectional design for analytic research. According to the geographical regions of Mongolia, 5,300 children aged 0-9 years were randomly selected, and information about immunization against hepatitis B virus was collected from the health records (pink notebook) and each child’s mother or guardians. Also recorded vaccination type, dose, and period of vaccination. Data analysis was done using SPSS 26.0 software. Results: According to the study results 94.9% of children living in cities and 90.3% of children living in rural areas were vaccinated against hepatitis B virus. The birth dose of HBV vaccine within 24 hours after birth was inject on time by a relatively high percentage in urban (98.6%) and rural (97.5%) areas. Also 75.5% of male children and 76.9% of female children who participated in the study received the full dose of hepatitis B vaccine. It was also observed that the percentage of full doses of the Penta vaccine coverage rate decreased as the child’s age increased. A large difference was observed in the coverage rate of the full dose of Penta vaccine compared to the national coverage rate data report. Conclusion: Despite the high coverage rate of within 24-hour doses of the HBV vaccine (98.6% in urban areas and 97.5% in rural areas), the coverage rate of full doses of the Penta vaccine is insufÏcient and lower level than national reported level.