Hepatitis D Antibody Test: Results Guide for Canadians

The hepatitis D antibody test is a simple blood test that determines whether your body has been exposed to the hepatitis D virus (HDV), one of the most severe forms of viral hepatitis known to affect humans. For Canadians, understanding this test is essential because early detection can prevent serious liver damage, including cirrhosis and liver failure.

How the Hepatitis D Antibody Test Works in Canada

Because the hepatitis D virus can only infect people who already carry hepatitis B, hepatitis D screening in Canada is especially important for individuals living with chronic hepatitis B. In this guide, we explain how the test works, what your results mean, the difference between coinfection and superinfection, and when you should speak with your doctor about getting tested.

What Is Hepatitis D?

Types of Hepatitis D Infection: What Your Hepatitis D Antibody Test Results May Indicate

Infection Type	Characteristics	Typical Antibody Test Findings	Management Approach
Acute Coinfection (HDV + HBV)	Simultaneous infection with both hepatitis B and D viruses; often self-limiting in adults	Anti-HDV IgM detected; HBsAg positive; anti-HDV IgG may appear later	Supportive care; monitoring liver function; most cases resolve without chronic progression
Superinfection	HDV infection occurring in a person already chronically infected with HBV; carries highest risk of severe disease	High-titre anti-HDV IgG; persistent anti-HDV IgM; HBsAg positive	Referral to hepatology specialist; pegylated interferon-alpha therapy; regular liver monitoring every 6 months
Chronic HDV Infection	Ongoing HDV replication lasting more than 6 months; accelerates cirrhosis and liver failure compared to HBV alone	Persistent anti-HDV IgG and IgM; HDV RNA detectable in serum	Long-term antiviral therapy; liver fibrosis assessment; hepatocellular carcinoma surveillance; transplant evaluation if advanced
Resolved HDV Infection	Previous HDV exposure with viral clearance; no active replication; may still carry HBV	Anti-HDV IgG positive; anti-HDV IgM negative; HDV RNA undetectable	Continued HBV management; routine follow-up with primary care or specialist in Canada’s hepatitis programs
Occult or Low-Level Infection	Very low viral levels; may be missed on standard testing; seen in immunocompromised patients	Anti-HDV antibodies may be low or absent; HDV RNA testing required for confirmation	Confirmatory HDV RNA PCR testing; immunology review; close monitoring in HIV-coinfected individuals

Hepatitis D is a liver infection caused by the hepatitis D virus. It is unique because it cannot survive on its own. The hepatitis D virus needs the hepatitis B virus to replicate inside the body.

This means you can only get hepatitis D if you already have hepatitis B. According to the World Health Organization (WHO), an estimated 15 to 20 million people worldwide are living with hepatitis D. However, many cases go undiagnosed.

Because hepatitis D depends on hepatitis B, it is one of the most preventable viral liver diseases. Getting vaccinated against hepatitis B also protects you against hepatitis D.

How Does the Hepatitis D Antibody Test Work?

The hepatitis D antibody test looks for antibodies in your blood. Antibodies are proteins your immune system makes when it fights an infection. When your body is exposed to the hepatitis D virus, it produces specific antibodies called anti-HDV antibodies.

The test uses a method called enzyme immunoassay (EIA). This is a standard lab technique that detects the presence of these antibodies in a blood sample. No special preparation is needed before the test. You do not need to fast or change your diet beforehand.

What Antibodies Does the Test Detect?

There are two main types of anti-HDV antibodies. Each one tells your doctor something different about the stage of your infection.

• Anti-HDV IgM antibodies: These appear within the first 2 to 3 weeks after infection. In acute hepatitis D, they usually disappear within about 2 months. However, in cases of superinfection, they can persist for up to 9 months.
• Anti-HDV IgG antibodies: These develop after the IgM antibodies. They can stay in the blood for years, even after the active infection has cleared. They are also present in chronic hepatitis D cases.

Your doctor will look at which type of antibody is present. This helps them understand whether your infection is new, ongoing, or from the past.

Understanding Your Hepatitis D Antibody Test Results

A positive hepatitis D antibody test does not automatically mean you have an active infection right now. It simply means your body has been exposed to the virus at some point. These antibodies can remain in your blood for many years after the infection has resolved.

Therefore, your doctor will consider your full clinical picture. They will look at your symptoms, your hepatitis B status, and other lab results together. This gives a more complete and accurate diagnosis.

Positive Results: What They Can Mean

A positive result may indicate one of the following situations:

• A current active hepatitis D infection (acute or chronic)
• A past infection that has since resolved
• An early-stage infection where the immune response is just beginning
• A weakened immune system that delayed the antibody response

In some cases, a false positive result can occur. This can happen due to cross-reactions with antibodies from other viral infections. Your doctor may order follow-up tests to confirm the result.

Negative Results: What They Can Mean

A negative result usually means you have not been exposed to the hepatitis D virus. However, in very early infections, antibodies may not yet be detectable. Furthermore, people with weakened immune systems may produce fewer antibodies, which can also lead to a negative result even when the virus is present.

If your doctor still suspects hepatitis D based on your symptoms, they may recommend additional testing, such as an HDV RNA test.

Coinfection vs. Superinfection: Key Differences

There are two ways a person can get hepatitis D. The first is coinfection, and the second is superinfection. These two situations have very different outcomes.

Coinfection

Coinfection happens when a person gets both hepatitis B and hepatitis D at the same time. This increases the risk of developing fulminant hepatitis, a rare but life-threatening form of acute liver failure. However, around 90% of people with coinfection recover fully. Chronic hepatitis D is less likely to develop in these cases.

Superinfection

Superinfection happens when a person who already has chronic hepatitis B then gets infected with hepatitis D. This is generally a more serious situation. Superinfection significantly increases the risk of rapid progression to liver cirrhosis, which is serious scarring of the liver. Spontaneous recovery from superinfection is rare. As a result, these patients need close monitoring and medical care.

Understanding which type of infection you have helps your healthcare provider plan the right treatment and follow-up. Learn more about hepatitis B and its complications at Mayo Clinic.

Why Testing for Hepatitis B at the Same Time Matters

Because hepatitis D only occurs alongside hepatitis B, your doctor will always evaluate both infections at the same time. Testing for hepatitis D alone gives an incomplete picture. Your results need to be interpreted in the context of your hepatitis B status.

In addition to the hepatitis D antibody test, your doctor may order the following tests:

• HBV DNA viral load: This measures how much hepatitis B virus is in your blood. It shows whether hepatitis B is actively replicating.
• HBe antigen (HBeAg): This protein indicates that hepatitis B is actively replicating and is more infectious.
• Anti-HBe antibodies: The presence of these antibodies usually suggests lower hepatitis B replication activity.
• HDV antigen test: This can directly detect the hepatitis D virus protein in blood during acute infection.

Together, these tests give your doctor a full picture of what is happening in your liver. This combined approach leads to more accurate diagnoses and better treatment decisions.

Who Should Get a Hepatitis D Antibody Test?

Not everyone needs this test. However, certain groups of people are at higher risk and may benefit from hepatitis D antibody testing. Your family doctor can help you decide if this test is right for you.

Testing may be recommended for people who:

• Have been diagnosed with hepatitis B, especially chronic hepatitis B
• Have unexplained worsening of liver disease despite stable hepatitis B
• Have recently had acute hepatitis B with severe symptoms
• Share needles or injection drug equipment
• Have had unprotected sex with a person who has hepatitis D or B
• Have received blood transfusions or organ transplants in countries with limited screening
• Are healthcare workers with potential exposure to blood

In Canada, provincial health plans generally cover blood tests ordered by a physician when there is a clinical reason. Talk to your family doctor or a specialist about whether this test is medically necessary in your situation. Coverage can vary by province, so it is worth checking with your provincial health authority.

For more general information on viral hepatitis in Canada, visit Health Canada’s official website.

When to See a Doctor

If you think you may have been exposed to hepatitis B or hepatitis D, do not wait. Contact your family doctor as soon as possible. Early diagnosis can make a significant difference in outcomes, especially for hepatitis D.

You should seek medical attention if you notice any of the following symptoms:

• Yellowing of the skin or eyes (jaundice)
• Unusual fatigue or weakness that does not go away
• Dark urine or pale-coloured stools
• Pain or discomfort in the upper right side of your abdomen
• Nausea, vomiting, or loss of appetite
• Swelling in the abdomen

If you do not have a family doctor, a walk-in clinic can assess your symptoms and order initial bloodwork. From there, you may be referred to a gastroenterologist or hepatologist (liver specialist) for further care. Many Canadian cities also have liver disease clinics connected to teaching hospitals and health centres.

Always speak with a qualified healthcare provider before drawing conclusions from any lab result. Only a doctor can properly interpret your test in the context of your full health history.

Key Takeaways

• The hepatitis D antibody test detects antibodies that show exposure to the hepatitis D virus.
• Hepatitis D is the most severe form of human viral hepatitis and can only occur alongside hepatitis B.
• There are two types of anti-HDV antibodies: IgM (early infection) and IgG (later or chronic infection).
• A positive result does not always mean an active infection — past exposure can also cause a positive result.
• Coinfection (getting both viruses at once) has a better recovery rate than superinfection (getting HDV after chronic HBV).
• Hepatitis D testing should always be done alongside hepatitis B testing for accurate results.
• No preparation is needed for this blood test, and it is ordered by a doctor based on clinical need.
• If you have hepatitis B or are at risk, speak with your family doctor or visit a walk-in clinic to discuss testing.
• Always consult a qualified healthcare provider to interpret your results and guide your care.