The presence of HBsAb in the serum generally indicates recovery and immunity from hepatitis B infection. With naturally occurring hepatitis infections, anti-HBs usually appear in serum several weeks after disappearance of HBsAg; also known as HBsAb, anti-HBs, Australia Bs antibody, and HBV antibody.
Normal range:
<5.00 mIU/mL: Negative
≥5.00 mIU/mL and <12.0 mIU/mL: Indeterminate
≥12.0 mIU/mL: Positive
Use
Identifying current and previous exposure to HBV. Determining adequate immunity from hepatitis B vaccination
Interpretation
Increased In
Recovery from acute or chronic HBV infection, or acquired immunity from HBV vaccination.
Positive results (quantitative anti-HBs levels of ≥12 mIU/mL) indicate an adequate immunity to hepatitis B from previous HBV infection or HBV vaccination.
Screen for individuals at high risk for exposure, such as hemodialysis patients, persons with multiple sex partners, persons with a history of other STDs, IV drug abusers, infants born to infected mothers, individuals residing in long-term residential facilities or correctional facilities, recipients of blood- or plasma-derived products, allied health care workers, and public service employees who come in contact with blood and blood products.
Decreased In
Inadequate immune response to HBV vaccination.
Limitations
Passively acquired anti-HBs (i.e., transfusion of whole blood or plasma, recent immune globulin treatment) can yield positive results without indicating permanent immunity to HBV infection.
Anti-HBs levels from previous hepatitis B or HBV vaccination may fall below detectable levels over time.
Not useful for diagnosis of acute HBV infection. Does not differentiate between vaccine-induced immunity and immunity after recovery from hepatitis B infection without further tests like hepatitis B core total antibodies.
Coexistence of HBsAg/HBsAb reported in 24% patients. In most cases, the antibodies are unable to neutralize circulating virions. These are regarded as carriers.