Hepatitis B Antigen

Although there are multiple tests for HBV, the main screening test is an antigen test which looks for active virus.  The most influential marker for HBV detection is hepatitis B surface antigen.  People that have either been vaccinated against hepatitis B or that have cleared infection on their own will test positive for the hepatitis B antibody, so antibody tests are rarely used to determine active hepatitis B infection.

Hepatitis C Antibody

The HCV ELISA is widely used for detecting antibodies to HCV.  Since an individual with resolved infection will have a life long antibody response, confirmed positive antibody tests mean that at one time or another the person had been exposed to the virus.  These tests are very effective in ruling out HCV.  The most up to date EIA is capable of antibody detection as early as 6-8 weeks.  While a negative test at this time can be extremely useful, it is best to wait about 3 months to avoid the need for a follow up test.

Hepatitis C RNA by PCR

The Hepatitis C RNA by PCR is the most sensitive test for detecting infection.

While most healthy individuals are accustomed to waiting 3 months for a conclusive result, the Hepatitis C RNA can provide conclusive results after only 28 days.

The RNA PCR is an antigen test, that is, a test that looks directly for the virus.  This test is conclusive well before the antibody test because it is not dependant on an antibody response.  It is looking for the actual genetic material of the Hepatitis C virus.  If the specimen contains a particular HCV segment, it will be synthetically amplified (multiplied) so that it's easily detected.  If even a small amount of virus is present in the specimen it is easily detected by this test.   Although the manufacturer recommends testing after 28 days for conclusive results, a RNA PCR can clearly be used well before that time as a strong indicator.  For patients with a high level of anxiety or strong reason to suspect infection, the RNA PCR can be useful even days after exposure.

If you have reason to believe you have recently been exposed to someone who is Hepatitis C positive, had a recent needle stick, or had some other potential recent blood exposure to HCV you could benefit from early testing or treatment.  Call a testing representative for further information.