Seropositivity of antibody to hepatitis B core antigen among hepatitis B surface antigen-negative vaccinated individuals aged 5-12 years in North West Ethiopia

Background: Infection with the hepatitis B virus (HBV) is still a major global public health concern, especially in Ethiopia. Evidence suggests that some children in Ethiopia who have received hepatitis B vaccinations are still contracting HBV.

Objective: The main aim of this study was to detect antibodies to hepatitis B core antigen (anti-HBc) among vaccinated hepatitis B surface antigen (HBsAg)-negative individuals in North-West Ethiopia.

Methods and materials: A community-based cross-sectional study was conducted among 158 children aged 5-12 years from April 2021 to November 2021. A simple random sampling technique was used to recruit study participants. After 3-5 ml of venous blood was drawn from each study participant, a serum sample was utilized to determine hepatitis B surface antigen (HBsAg) and anti-hepatitis B core antibodies (anti-HBc) by enzyme-linked immunosorbent assay (ELISA). Logistic regression with a 95 % CI was used to show the statistical association.

Results: The total seropositivity of anti-HBc among vaccinated HBsAg-negative participants was 8/158 (5.1 %) (95 % CI: 2.0-9.0). Multivariable logistic regression revealed that children who had a previous history of blood transfusion were six times (AOR: 6.135, 95 % CI: 4.063, 10.752) (P < 0.006) more likely to develop anti-HBc. Moreover, children who had a previous history of surgery were five times (AOR: 5.116, 95 % CI: 3.123, 8.718) (P < 0.002) more likely to become anti-HBc seropositive.

Conclusion: There was a significant seroprevalence of anti-HBc in our study area, suggesting possible exposure to the virus despite immunization.