Hepatitis A Virus Test
virus (HAV) test is a blood test that looks for proteins (antibodies) made by the body in response to the virus
that causes hepatitis A. These proteins will be present in your blood if you
have a hepatitis A infection now or have had one in the past. It is important
to identify the type of hepatitis virus causing the infection to prevent it
from spreading and to start the proper treatment.
HAV infection is
spread through food or water that has been contaminated by the feces (stool) of
an infected person.
IgM anti-HAV antibodies
indicate a recent infection with hepatitis A virus. IgM anti-HAV antibodies
generally can be detected in the blood as early as 2 weeks after the initial
HAV infection. These antibodies disappear from the blood 3 to 12 months after
IgG anti-HAV antibodies mean
that you have had a hepatitis A viral infection. About 8 to 12 weeks after the
initial infection with hepatitis A virus, IgG anti-HAV antibodies appear and
remain in the blood for lifelong protection (immunity) against HAV.
Hepatitis A vaccine is available to prevent an HAV
infection. If you have had this vaccine and you have anti-HAV antibodies, this
means the vaccination was effective.
Why It Is Done
Hepatitis virus testing is done
- Identify the type of hepatitis virus causing a
- Screen people (such as doctors, dentists, and
nurses) who have an increased chance of getting or spreading hepatitis
- Screen potential blood donors and donor organs to prevent the
spread of hepatitis A.
- Find out whether a person has antibodies
after getting a hepatitis A vaccine. If you had this vaccine and you now have
antibodies to the hepatitis A virus (anti-HAV antibodies) in your blood, this
means the vaccination was effective (you are immune to hepatitis
- Find out if a hepatitis A infection is the cause of abnormal
liver function tests.
How To Prepare
You do not need to do anything before
you have this test.
Talk to your doctor about any concerns you
have regarding the need for the test, its risks, how it will be done, or what
the results will mean. To help you understand the importance of this test, fill
medical test information form(What is a PDF document?).
How It Is Done
The health professional taking a sample
of your blood will:
- Wrap an elastic band around your upper arm to
stop the flow of blood. This makes the veins below the band larger so it is
easier to put a needle into the vein.
- Clean the needle site with
- Put the needle into the vein. More than one needle stick
may be needed.
- Attach a tube to the needle to fill it with
- Remove the band from your arm when enough blood is
- Put a gauze pad or cotton ball over the needle site as
the needle is removed.
- Put pressure on the site and then put on a