Abstract:
Background: Hepatitis B virus (HBV) is the leading cause of viral hepatitis and about 240
million people worldwide are chronic carrier. The virus was known widely prevalent in Ethiopia
and has several serious complications. The vaccines used for the virus have an outstanding
record of safety and effectiveness; however, about 10% of the vaccinees still remain susceptible
to HBV, especially those vaccinees were from infected mothers. The disease burden among
children and sero-protection of HBV vaccine is mainly unknown in the study area. Therefore,
this study assessed the sero-prevalence of HBV infection and sero-protection of HBV vaccine
among children in Jimma town.
Methods: Community based cross-sectional study was conducted among 900 children of 5 to 9
years of age from June to December, 2016. Simple random sampling technique was employed to
recruit study participants by proportional allocations into different Kebeles of Jimma town. Data
was collected by using pretested questionnaire and about 3-5ml of blood sample was collected
and tested for HBsAg, anti-HBc and anti-HBs by using ELISA (Bio-rad, Monolisa, Lacquote,
France) technique. Data were analysed using chi-square and logistic regression test.
Result: This study revealed that the HBsAg and anti-HBc prevalence among all participants
were 3.5% and 3.8%, respectively. The prevalence of HBsAg among vaccinated and nonvaccinated was 2.1% and 7.0% respectively. Anti-HBc positivity was 1.1% and 6.2% among
vaccinated and non-vaccinated children. The sero-protection of HBV vaccine among fully
vaccinated children showed that 71.6% against chronic HBsAg carriage whereas 83.4% against
total HBV infection. It was also found that 58.4% of vaccinated children retained protective level
of HB surface antibodies, ≥ 10 mIU/ml with the mean of 50 mIU/ml. Multiple logistic regression
revealed that lack of vaccination (AOR =2.788, P < 0.029), child who were born at home
(AOR= 3.211, P < 0.009) and hospital admission (AOR= 7.122, P <0.001) were the significant
predicting variables for HBsAg positivity Conclusion: The sero-prevalence of hepatitis B infection is high among children who have not
been vaccinated for the virus. Hepatitis B vaccine has contributed to the reduction of the
infection in this endemic area, though further efforts are required to improve timely vaccination
and its coverage. The prevalence of protective anti-HBs is low among fully vaccinated children,
hence, it is better to include the monovalent birth dose of the vaccine and conduct further studies
to evaluate underlining cuases for wanning of serum anti-HBs level.
