Interpretation of Reactive Hepatitis A Total Antibody and Hepatitis B Surface Antibody
A reactive Hepatitis A total antibody (anti-HAV total) combined with a reactive Hepatitis B surface antibody (anti-HBs) indicates immunity to both Hepatitis A and Hepatitis B viruses, typically from either past resolved infections or successful vaccination. 1
Hepatitis B Surface Antibody (Anti-HBs) Interpretation
The reactive anti-HBs result indicates protective immunity against Hepatitis B virus (HBV) infection, with levels ≥10 mIU/mL considered protective. 1
- Anti-HBs develops either from successful HBV vaccination or recovery from natural HBV infection. 1
- Individuals with positive anti-HBs (≥10 mIU/mL) are protected against HBV infection and cannot transmit the virus to others. 1
- This person does not require HBV vaccination if anti-HBs is already documented as positive. 1
Determining the Source of Anti-HBs Immunity
To distinguish between vaccine-induced immunity versus immunity from past natural infection, additional testing is needed:
- If HBsAg negative + anti-HBc (hepatitis B core antibody) negative + anti-HBs positive = immunity from vaccination. 1
- If HBsAg negative + anti-HBc positive + anti-HBs positive = immunity from resolved natural HBV infection. 1
- The presence of anti-HBc indicates past or present HBV infection, while its absence indicates vaccine-induced immunity. 2, 3
Hepatitis A Total Antibody (Anti-HAV Total) Interpretation
A reactive anti-HAV total antibody indicates past exposure to Hepatitis A virus (HAV) with protective immunity, either from natural infection or vaccination. 2
- Anti-HAV total includes both IgM and IgG antibodies and indicates a protective immune response to infection, vaccination, or passively acquired antibody. 2
- This result confirms the person is immune to HAV and does not require Hepatitis A vaccination. 4
Important Caveat Regarding Anti-HAV Total
- In rare cases during very early acute Hepatitis A infection, anti-HAV IgM may be non-reactive while anti-HAV total is reactive due to assay sensitivity differences. 5
- However, this scenario is clinically distinguishable by the presence of acute hepatitis symptoms, elevated liver enzymes, and the temporal evolution of serologic markers. 5
- In an asymptomatic individual with normal liver function, a reactive anti-HAV total reliably indicates immunity. 2
Clinical Significance and Management
This serologic profile indicates the individual is immune to both Hepatitis A and Hepatitis B and requires no vaccination for either virus. 1, 4
Monitoring Considerations
- For healthcare workers and other high-risk individuals, periodic testing of anti-HBs levels may be warranted. 1
- Booster doses of HBV vaccine may be considered for certain high-risk individuals if anti-HBs levels fall below 10 mIU/mL. 1
- In immunocompromised patients, more frequent monitoring of anti-HBs levels may be appropriate. 1
Special Populations
- Patients requiring immunosuppressive therapy: Those with resolved HBV infection (anti-HBc positive, anti-HBs positive) have a 3-45% risk of HBV reactivation and may require HBV DNA testing and antiviral prophylaxis. 6
- Patients with chronic liver disease: If this serologic pattern exists in the context of chronic liver disease from another cause (e.g., hepatitis C), these individuals are protected against superinfection with HAV or HBV. 4
Pitfall to Avoid
- Passively acquired anti-HBs from recent blood product transfusion can cause a false-positive result that does not confer true immunity. 7
- If the patient received blood products, fresh frozen plasma, or hepatitis B immune globulin (HBIG) within the past few weeks, repeat testing after 3-6 months is recommended to confirm endogenous antibody production. 7