Hepatitis B is a viral infection that attacks the liver, causing complications like cirrhosis and liver cancer when left untreated. It spreads through contact with infected blood or bodily fluids (e.g., sexual contact, childbirth, the sharing of needles or other personal items like razors).
It’s estimated that chronic hepatitis B affects nearly 1 million people in the U.S. and approximately 296 million people globally, according to the Centers for Disease Control and Prevention (CDC). Possible symptoms of hepatitis B infection can include fatigue, nausea, vomiting, joint pain and jaundice (yellowing skin and eyes). However, many people with hepatitis B have no symptoms at all.
While many people are vaccinated for hepatitis B during childhood, not everyone receives the vaccine, and immunity from vaccination can decrease over time.
Here’s what you need to know about hepatitis B vaccination and immunity.
Who should receive the hepatitis B vaccine?
The CDC recommends hepatitis B vaccination for:
- All infants, children or adolescents younger than 19 years of age who have not been vaccinated
- All adults aged 19 through 59 years
- Adults aged 60 years or older with risk factors for hepatitis B infection
Vaccines are extremely effective at protecting against hepatitis B infection, and several brands are approved for use. The vaccines differ most in schedule, whether administered as a two-, three- or four-shot series. Administration of the shots must be spread out over a few months or even up to a year, and it is very important to return for all required vaccination appointments to reach full immunity. Healthcare providers may recommend one specific hepatitis B vaccine over another based on local availability or other patient conditions.
How long does hepatitis B vaccine immunity last?
Studies show that hepatitis B immunity persists for at least 30 years among healthy people who started vaccination at less than 6 months of age.
However, immunity can decrease over time. And without protection against hepatitis B, exposure to the hepatitis B virus can lead to infection. An untreated acute hepatitis B infection can increase the risk of more serious health issues, including cirrhosis and liver cancer.
It's also worth noting that, in the U.S., hepatitis B vaccination is often a requirement for entry into public spaces like daycare or school—hence why you may have already been vaccinated when you were younger.
Even if you did receive the hepatitis B vaccine as a child, the only way to know if you still have immunity is to test your hepatitis B surface antibody levels.
How to find out your hepatitis B immunity status
There are a few different blood markers that can provide information about your history with hepatitis B. Labcorp OnDemand’s Hepatitis B Immunity Test measures your hepatitis B surface antibodies, which are proteins produced by the immune system. The immune system can make antibodies in response to either vaccination or a prior resolved hepatitis B infection. Presence of hepatitis B surface antibodies is a good indicator that the body is sufficiently prepared to respond to viral exposure, but it does not tell you whether your immunity is from vaccination or prior infection. Knowing your hepatitis B immunity status can inform conversations with your healthcare provider about whether a hepatitis B booster shot or additional lab tests may be needed.
Don’t guess if your hepatitis B vaccine immunity has waned. Take control by testing your hepatitis B antibody levels and discussing your results with your healthcare provider.
