Hepatitis B virus (HBV) infection is a major cause of acute and chronic hepatitis, cirrhosis, and liver cancer.

HBsAg (surface antigen) is the earliest marker of HBV infection and indicates that the person is infectious.

The ELISA (Enzyme‑Linked Immunosorbent Assay) method provides high sensitivity and specificity for detecting HBsAg.

Clinical uses include:

Screening for Hepatitis B infection in blood donors, healthcare workers, and general population.

Diagnosing acute or chronic HBV infection.

Monitoring infectivity and disease progression.

Supporting evaluation in liver disease workups.

Often performed alongside HBV DNA, HBeAg, Anti‑HBs, and Anti‑HBc tests for comprehensive assessment.

Analyte: Hepatitis B surface antigen (HBsAg) in serum.

Normal Result: Negative (no HBsAg detected).

Abnormal Findings:

Positive HBsAg: Indicates active HBV infection (acute or chronic).

Persistent positivity (>6 months): Suggests chronic Hepatitis B.

Clinical Use:

Provides a direct marker of HBV infection and infectivity.

Helps guide diagnosis, monitoring, and treatment planning.

Supports hepatology, gastroenterology, infectious disease, and preventive medicine evaluations.