From the Guidelines
Hepatitis B surface antibody (anti-HBs) indicates immunity against the hepatitis B virus, with levels of 10 mIU/mL or higher generally considered protective against infection. This immunity can develop either from successful vaccination against hepatitis B or from recovering from a past hepatitis B infection 1. The antibody specifically targets the surface antigen (HBsAg) of the hepatitis B virus, preventing the virus from infecting liver cells.
Interpretation of Anti-HBs
If you test positive for hepatitis B surface antibody but negative for hepatitis B surface antigen and core antibody, it typically means you have vaccine-induced immunity. If you have both the surface antibody and core antibody, it suggests immunity from a resolved natural infection 1. This antibody protection is generally considered long-lasting, especially after natural infection, though some vaccinated individuals may show declining antibody levels over time.
Clinical Implications
The presence of anti-HBs is crucial in determining the immune status of an individual against hepatitis B virus infection. It is essential in guiding vaccination strategies, post-exposure prophylaxis, and in assessing the risk of transmission in various settings, including healthcare and personal contacts 1.
Key Points
- Anti-HBs levels of 10 mIU/mL or higher are considered seroprotective 1.
- The interpretation of anti-HBs should be considered in the context of other serologic markers, including HBsAg and anti-HBc 1.
- Vaccinated individuals with anti-HBs levels below 10 mIU/mL may require revaccination or other protective measures against HBV infection 1.
From the Research
Hepatitis B Surface Antibody Indication
The presence of Hepatitis B (Hep B) surface antibody, also known as anti-HBs, indicates that an individual has been exposed to the Hepatitis B virus (HBV) and has developed immunity to it. This immunity can be due to:
- Natural infection with HBV, where the individual has recovered and developed anti-HBs antibodies 2
- Vaccination against HBV, which stimulates the production of anti-HBs antibodies 2, 3
Protective Immunity
The presence of anti-HBs antibodies is generally considered to indicate protective immunity against HBV infection. However, the level of anti-HBs antibodies can decrease over time, and it is unclear whether protective immunity is maintained at low antibody levels 4, 2. Factors that affect the maintenance of anti-HBs antibody levels in the bloodstream have been reported, and the presence or absence of anti-HBs antibodies in the context of HBV immunity has been the subject of extensive discussion 2.
Clinical Implications
The detection of anti-HBs antibodies has important clinical implications, particularly in the context of liver transplantation. For example, the presence of anti-HBs antibodies in patients with core antibody-positive liver transplantation has been shown to reduce the risk of de novo HBV infection 5. Additionally, the detection of anti-HBs antibodies can be used to diagnose acute HBV infection after recent exposure, although misdiagnosis can occur due to unexpected or atypical behavior of serological markers 6.
Key Findings
Key findings related to anti-HBs antibodies include:
- Anti-HBs antibodies develop after natural infection with HBV or vaccination against this virus 2
- The presence of anti-HBs antibodies indicates protective immunity against HBV infection, but the level of antibodies can decrease over time 4, 2
- The detection of anti-HBs antibodies has important clinical implications, particularly in the context of liver transplantation and diagnosis of acute HBV infection 5, 6