Titer tests measure antibodies in your blood. Antibodies are proteins produced by your immune system in response to foreign substances like viruses, bacteria, or chemicals.

A hepatitis B titer test specifically looks for antibodies that suggest that you’re immune from the hepatitis B virus — either from vaccination or previous exposure to the virus.

Keep reading to learn more about hepatitis B titer tests including what they’re used for, what the results mean, and what to expect during the test.

A hepatitis B titer test measures antibodies in your blood to see if you’re immune either due to vaccination or previous infection.

Hepatitis B is a viral infection that targets your liver. It can be transmitted by coming into contact with the bodily fluids of an infected person. A person with the virus can also infect their child during birth.

Hepatitis B can develop into a chronic (or long-term) infection. Chronic infection occurs when your body can’t fight off the virus within six months. Chronic hepatitis B infections most commonly develop in young children less than six years old, especially in infants.

Hepatitis B titer tests can be used to evaluate:

  • whether a high-risk person is immune to hepatitis B
  • whether hepatitis B immunoglobulin is needed after a needle prick
  • whether a person needs a hepatitis B vaccine
  • immunity after vaccination

The Centers for Disease Control and Prevention (CDC) recommends that the following people get screened for hepatitis B infection:

  • infants born with a mother with hepatitis B
  • pregnant women
  • people with alanine aminotransferase levels over 19 IU/L for women and 30 IU/L for men
  • blood and tissue donors
  • people with end-stage kidney disease
  • people taking immunosuppressive therapy, such as people who received an organ transplant
  • people living with or having sex with a person with hepatitis B
  • people with HIV
  • people injecting drugs
  • men who have sex with men
  • people born in countries with a hepatitis B prevalence greater than 2 percent
  • people born in the United States not vaccinated as children and with parents born in regions with more than 8 percent hepatitis B prevalence

You may need your titer test results as proof of hepatitis B immunity in order to get into healthcare programs at many schools — for example, the nursing program at Lone Star College. In the United States, employers are not allowed to withdraw a job offer if they learn you have hepatitis B.

A hepatitis titer test requires a healthcare professional to draw a small amount of blood for testing.

No special preparation is needed beforehand. If needles or the sight of blood make you anxious, you may want to arrange a drive ahead of time in case you feel faint.

Here’s what will typically happen during this test:

  1. The person administering the test ties a band around your arm to make your veins easier to find.
  2. The person sterilizes the injection site and inserts a small needle into your vein. You may feel a sharp pain, but it should quickly pass.
  3. After the needle is removed, the test administrator asks you to apply a gentle pressure with a gauze or a cotton ball.
  4. A bandage is applied to the area, and you’re free to leave.

Home tests that require a fingerpick are also available. The results of your tests are generally available within 3 days.

A hepatitis B blood panel consists of three tests that can be done with just one blood sample:

  • Hepatitis B surface antigen (HBsAG). A positive test indicates that you’re infected with hepatitis B and that you can spread it to other people. Further tests are needed to see if you have an acute or chronic infection.
  • Hepatitis B core antibody (Anti-HBc or HBcAb). A positive result can indicate a past or current hepatitis B infection, but doesn’t mean you’re immune. A positive result needs to be interpreted by a doctor by examining the results of the other two tests.
  • Hepatitis B surface antibody (Anti-HBs or HBsAb). A positive test indicates that you’re protected from hepatitis B either through previous infection or vaccination (although it’s still possible to infect other people in some rare cases).

The combination of these tests can indicate your hepatitis B status and whether you need to be vaccinated. Your test will give a negative or positive result for each category depending on whether your results are above or below the cutoff value.

Most people’s test results fall into the following categories. But it’s possible to have a result that doesn’t fall into one of these groups. If you’re reading your results yourself, be careful not to confuse “HBsAb” with “HBcAb.”

HBsAGHBsAb (anti-HBs)HBcAb (anti-HBc)Interpretation
negativenegativenegative-Not immune
-Has not had previous infection
-Vaccination recommended
negativepositivepositive-Immune
-Have previously been infected
-Not contagious
-Vaccination not needed
negativepositivenegative-Have previously been vaccinated
-Not infected
-No vaccination needed
positivenegativePositive-Infected
-Contagious
-More testing needed
negativenegativepositive-possibly infected
-possibly contagious
-More testing needed

According to the CDC, an anti-HBs titer greater than 10IU/ml is associated with hepatitis B immunity after vaccination. But research has found that anti-HBs decline over time.

A 2021 study found that more than 95 percent of people had anti-HBs levels greater than 10IU/L two years after vaccination. But this rate decreased to 70 percent after eight years.

Research also suggests that hepatitis B immunity seems to persist even when antibodies levels drop.

The cost of a hepatitis B test varies based on where you get the test. Prices range from roughly $24 to $110.

Your insurance may cover some or all of the cost. Under the Affordable Care Act, all new health plans must cover preventative services — including hepatitis B vaccination and testing — without a deductible or copay.

It can be difficult to understand what the results of your test mean. A healthcare provider can help you interpret your results and decide whether you need to take further action:

  • If your results suggest that you’re already immune to hepatitis B and aren’t contagious, you likely won’t need to do anything.
  • If your results suggest that you’re not immune, a doctor may recommend vaccination, especially if you’re somebody who’s at a high risk of infection.

You may also need additional testing if more information is needed to interpret your results.

Hepatitis B titer tests measure antibodies in your body to see if you’re immune to hepatitis B.

Your body produces antibodies in response to hepatitis B vaccination or from a previous infection. A healthcare professional can help you understand your results and recommend whether you need to take any particular course of action.