Immunity to hepatitis B means your body can recognize and neutralize the hepatitis B virus, either through vaccination or prior infection. This protection prevents the virus from causing chronic liver disease.
Your immune system produces antibodies against hepatitis B. These antibodies either come from a vaccine or from recovering from an infection. The most common antibody measured is called anti-HBs. A sufficient level of anti-HBs indicates protection.
There are two primary ways to develop immunity:
Hepatitis B can cause serious health issues, including chronic hepatitis, cirrhosis, and liver cancer. Immunity prevents these complications. The Centers for Disease Control and Prevention (CDC) recommends vaccination for infants, children, and high-risk adults.
Many people confuse immunity with lifelong protection. While the hepatitis B vaccine provides long-lasting immunity for most people, some may lose protection over time. Booster shots may be needed in certain cases.
Consider Jane, a healthcare worker who received the hepatitis B vaccine series. After vaccination, her blood test shows anti-HBs levels above 10 mIU/mL, indicating she is immune. This means if she's exposed to the virus at work, her immune system can fight it off effectively.