Strategic analysis of hepatitis B virus serological profile and the diagnostic utility of HBcrAg across Osun and Plateau State, Nigeria.

Hepatitis B virus (HBV) infection remains a major concern in Nigeria. Nationally, increasing infection rates continue to pose a significant challenge, which may be due to inadequate diagnosis. Known markers, such as Hepatitis B Surface Antigen (HBsAg) and Hepatitis B e antigen (HBeAg), are good at indicating exposure rates, but generally poor at reflecting active viral replication. The hepatitis B core-related antigen (HBcrAg) may provide a clearer picture of the viral activity and treatment response. We conducted a cross-sectional study involving 450 participants aged 16-65 years from hospitals in Osun and Plateau States. HBsAg screening was performed using rapid diagnostic tests, confirmed by enzyme-linked immunosorbent assay (ELISA), and further evaluated for HBeAg and HBcrAg levels. Correlation analysis was used to test the relationships between these markers. Of the 450 participants screened, 188 (41.7%) were confirmed positive for HBV. HBcrAg was observed in adults aged 17-45 years, suggesting replication activity in symptom-free individuals. Atypical serological profiles, such as HBsAg and HBsAb co-positivity, were also identified. Incorporation of HBcrAg in HBV screening, especially in endemic countries, may be useful in assessing HBV replication stage, reactivation, and staging of chronic infection, especially in resource-limited settings.