Test Overview

Hepatitis C
virus (HCV) test is a blood test that looks for the genetic material (RNA) of the virus that causes hepatitis or for the proteins (antibodies) the body makes against
HCV. These
proteins will be present in your blood if you have a hepatitis C infection now
or have had one in the past. It is important to identify the type of hepatitis
virus causing the infection, to prevent its spread and choose the proper
treatment.

HCV is spread
through infected blood.

  • Anti-HCV antibody tests
    look for antibodies to HCV in the blood, indicating an HCV infection has
    occurred. This test cannot tell the difference between an acute or long-term (chronic)
    infection. The enzyme immunoassay (EIA) may be the first test done to detect
    anti-HCV antibodies.
  • HCV RIBA is another test that detects antibodies to HCV. This test can tell whether a
    positive result was caused by an actual HCV infection or whether the result was
    a
    false-positive. This test may be done to double-check
    a positive EIA test result.
  • HCV genetic
    material (RNA) testing uses polymerase chain reaction (PCR) to identify an
    active hepatitis C infection. The RNA can be found in a person’s blood within 2 weeks after exposure to the virus. HCV RNA testing may be done to
    double-check a positive result on an HCV antibody test, measure the level of
    virus in the blood (called viral load), or show how well a person with HCV is
    responding to treatment.

    • HCV quantitative
      test (also called viral load) is often used before and during treatment to find
      out how long treatment needs to be given and to check how well treatment is
      working.
    • HCV viral genotyping is used to
      find out which genotype of the HCV virus is present. HCV has six genotypes, and
      some are easier to treat than others.

There is no vaccine available to prevent hepatitis
C.

Why It Is Done

Hepatitis C virus testing is done
to:

  • Find out if a hepatitis C
    infection is the cause of abnormal liver function tests.
  • Screen people (such as doctors, dentists, and
    nurses) who have an increased chance of getting or spreading a hepatitis C
    infection.
  • Screen potential blood donors and donor organs to
    prevent the spread of hepatitis C.
  • Screen people born from 1945 to 1965. People in this age group are more likely to have hepatitis C and not know it.footnote 1, footnote 2
  • Identify the type of hepatitis C virus causing
    the infection.

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
out the
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
    alcohol.
  • Put the needle into the vein. More than one needle stick
    may be needed.
  • Attach a tube to the needle to fill it with
    blood.
  • Remove the band from your arm when enough blood is
    collected.
  • 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
    bandage.

A home test kit
is available for hepatitis C (HCV). The kit contains a sharp instrument
(lancet) that you use to draw a small sample of blood from your fingertip. The
blood sample is then placed on a piece of collection paper and mailed in a
prepaid envelope to a lab for testing. Results are available in 10 days. You
are given an identification number to use when calling a toll-free number to
obtain confidential results. If the results of the test are positive, it is
important for you to make an appointment with your doctor to
confirm the test results, determine the amount of damage to your liver, and
determine whether antiviral therapy is an option.

How It Feels

The blood sample is taken from a vein in
your arm. An elastic band is wrapped around your upper arm. It may feel tight.
You may feel nothing at all from the needle, or you may feel a quick sting or
pinch.

Risks

There is very little chance of a problem from
having a blood sample taken from a vein.

  • You may get a small bruise at the site. You
    can lower the chance of bruising by keeping pressure on the site for several
    minutes.
  • In rare cases, the vein may become swollen after the
    blood sample is taken. This problem is called phlebitis. A warm compress can be
    used several times a day to treat this.

Results

The
hepatitis C virus (HCV) test is a blood test that
looks for the genetic material (RNA) of the hepatitis C virus or for the proteins (antibodies) the body makes against HCV.

Results of hepatitis C virus testing that show no infection are called
negative. This means that no antibodies against HCV or HCV genetic material was
found. Results are usually available in 5 to 7 days.

Hepatitis C virus tests
Normal (negative):

No hepatitis C antibodies are found.

No hepatitis C genetic material (RNA) is
found.

Abnormal (positive):

Hepatitis C antibodies are found. A test to detect HCV RNA
is needed to determine whether the infection is current or occurred in the
past. If HCV RNA is found, genotyping can determine which strain of HCV is
causing the infection.

Hepatitis C RNA is detected. This
result means a current hepatitis C virus infection.

Hepatitis
antibodies can take weeks to develop, so your results
may be negative even though you are in the early stage of an infection.

What Affects the Test

Many conditions can change HCV
antibody levels. Your doctor will talk with you about any abnormal results that
may be related to your symptoms and past health.

Your results
may need to be rechecked if you are taking some herbs, supplements, or other alternative medicine products.

What To Think About

  • There is no vaccine to prevent
    infections with the hepatitis C virus.
  • All donated blood and
    organs are tested for hepatitis C before being used.
  • Other tests
    that show how well the liver is working are usually done if your doctor thinks
    you may have hepatitis C. These may include blood tests for bilirubin, alkaline
    phosphatase, alanine aminotransferase, and aspartate aminotransferase.

  • Many
    states require that some types of hepatitis infections be reported to the local
    health department. The health department can then send out a warning to other
    people who may have been infected with the hepatitis virus, such as those who
    are close contacts of someone who has hepatitis C.

References

Citations

  1. Smith BD, et al. (2012). Recommendations for the identification of chronic hepatitis C virus infection among persons born during 1945-1965. MMWR, 61(RR-4): 1-32. Available online: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6104a1.htm.
  2. U.S. Preventive Services Task Force (2013). Screening for Hepatitis C Virus Infection in Adults: Recommendation Statement. Available online: http://www.uspreventiveservicestaskforce.org/uspstf/uspshepc.htm.

Other Works Consulted

  • Centers for Disease Control and Prevention (2003). Guidelines for laboratory testing and result reporting of antibody to hepatitis C virus. MMWR, 52(RR-03): 1-16. Available online: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5203a1.htm.
  • Pagana KD, Pagana TJ (2010). Mosby’s Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby.
  • Scott JD, Gretch DR (2007). Molecular diagnostics of hepatitis C virus infection: A systematic review. JAMA, 297(7): 724-732.

Credits

ByHealthwise Staff
Primary Medical Reviewer E. Gregory Thompson, MD – Internal Medicine
Adam Husney, MD – Family Medicine
Specialist Medical Reviewer W. Thomas London, MD – Hepatology

Current as ofMarch 3, 2017