Screening tests for hepatitis C virus are called HCV antibody tests. These tests do not look for the virus itself, but look for HCV antibodies (defense cells which the human body produces to fight HCV). A positive test result implies that someone has an HCV infection or has had one in the past. If the test result is unclear it is repeated and, if necessary, other types of blood tests are done.

Antibody tests
These indicate whether a person has had an HCV infection but cannot determine whether or not someone currently has the virus or how long they might have had hepatitis C.

After contracting the virus, it can take up to six months before the body seroconverts (starts producing antibodies). During this time someone is said to be in the window period. If they are experiencing an active HCV infection they could still return a negative antibody test.

People who return a positive result but have no risk history should be advised to have the test redone.

As with all test results, people are advised to ask for photocopies of the written test results. Should someone change doctors or want to get a second opinion, they then have their own records to show to other doctors or specialists.

If test results indicate that you have HCV, your doctor may measure the quantity of the virus in your blood (viral load) and evaluate the genetic makeup of the virus (genotype). There are six known HCV genotypes. Knowing which genotype you have will help your doctor determine the best course of treatment for you and how likely you are to respond to treatment.

Your doctor may also recommend a liver biopsy, a procedure in which a small sample of liver tissue is removed for microscopic analysis. Before the biopsy, you'll receive a local anesthetic to decrease the pain. Your doctor then inserts a thin needle into your liver to remove the tissue sample. Liver biopsy is unlikely to have any complications, although you may have some pain or bleeding afterward. Rarely, significant bleeding can occur.

Although a biopsy isn't necessary to confirm a diagnosis of hepatitis C, it can help determine the severity of the disease and guide treatment decisions. It may also help rule out other causes for your liver problem, such as alcoholic or drug-induced hepatitis, autoimmune hepatitis or excess iron (hereditary hemochromatosis).