Hepatitis A Antibody

Does this test have other names?

IgM anti-HAV, HAV-Ab IgM, HAV-Ab IgG, Anti-HAV

What is this test?

This test looks for antibodies in your blood. The test can find out if you are infected with the hepatitis A virus (HAV).

Hepatitis is an inflammation of your liver, often caused by an infection. Most hepatitis infections are caused by 1 of 5 viruses: hepatitis A, B, C, D, or E. Because the symptoms of all of these infections are similar, this blood test can tell your healthcare provider which type of virus you may have.

Your immune system makes antibodies when you are first infected with HAV. It can take 14 to 50 days to develop symptoms of hepatitis A after you become infected. The average time to get symptoms after you are infected is 30 days. Antibodies often begin to appear in your blood 5 to 10 days before you start having symptoms. They can stay in your blood for about 6 months after the infection. Some antibodies called IgG can last in your blood for life.

You can get HAV by eating or drinking a food or beverage contaminated with the virus. The virus is also in the bowel movements of infected people. So you could get infected by coming in contact with someone who has the infection. In rare cases, you can get the virus from a contaminated needle. 

HAV infection often goes away on its own in a few weeks or months. Once you have had HAV, you will likely never have it again. This is called having immunity to the infection.  

Why do I need this test?

You may need this test if your healthcare provider believes you may have a liver infection caused by HAV. Your provider may order this test if you have symptoms of HAV and you have a history that puts you at risk for being in contact with the virus. Risk factors for HAV include:

• Traveling to a country with high rates of HAV infection

• Having contact with or eating contaminated food

• Being in close contact with a person who has HAV

• Having sex with someone infected with HAV

• Being a man who has sex with men

• Working at a healthcare or daycare center

• Sharing needles for IV (intravenous) drug use

Symptoms of HAV often start suddenly and may include:

• Extreme tiredness (fatigue)

• Nausea

• Vomiting

• Stomachache

• Fever

• Light gray or clay-colored stools

• Yellow color of skin, eyes (jaundice)

• Dark-colored urine

Some people, especially children, may have HAV without symptoms. 

What other tests might I have along with this test?

Your healthcare provider may also check for antibodies to other types of hepatitis viruses. You may need other blood tests to check how your liver is working. Other tests for HAV are available, but the HAV antibody test is considered to be the most accurate.

What do my test results mean?

Test results may vary depending on your age, gender, health history, and other things. Your test results may be different depending on the lab used. They may not mean you have a problem. Ask your healthcare provider what your test results mean for you.

Normal results are negative or nonreactive, meaning that you don't have the hepatitis A antibodies in your blood.

If your test is positive or reactive, it may mean:

• You have an active HAV infection

• You have had an HAV infection in the past 

• You have gotten the hepatitis A vaccine

How is this test done?

The test is done with a blood sample. A needle is used to draw blood from a vein in your arm or hand. 

Does this test pose any risks?

Having a blood test with a needle carries some risks. These include bleeding, infection, bruising, and feeling lightheaded. When the needle pricks your arm or hand, you may feel a slight sting or pain. Afterward, the site may be sore. 

What might affect my test results?

No other factors can affect your results.

How do I get ready for this test?

You don't need to prepare for this test. Be sure your healthcare provider knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illegal drugs you may use.