Hepatitis C
Hepatitis C testing usually begins with blood tests that look for antibodies to the Hepatitis C virus, using a technique called an enzyme immunoassay. If this test is positive (showing that the body is making antibodies to fight the Hepatitis C virus), the person will be tested a second time to make sure that the results are correct and to see how serious the infection is. The results are confirmed using a technique called a recombinant immunoblot assay, and an HCV RNA polymerase chain reaction shows how serious the infection is. If the immunoblot is positive, but there are no Hepatitis C virus RNA, this shows that the person had an infection, but it cleared up either with treatment or on its own. If the immunoblot is negative, this shows that the immunoassay (the first test) was wrong, and the person does not have Hepatitis C. It takes six to eight weeks after a person gets infected before the immunoassay will test positive.