Hepatitis C antibody (anti-HCV)

The hepatitis C antibody test looks for antibodies the immune system produces after coming into contact with the hepatitis C virus. It is the standard first (screening) test for hepatitis C. A positive (reactive) result means exposure to the virus at some time — but, crucially, it does not by itself tell whether the infection is still active, because the antibody stays positive for life even in people whose infection has cleared or been cured. That is why a positive antibody is always followed by a test for the virus's genetic material, HCV RNA (a viral load), which confirms a current, active infection. If the RNA is positive, the infection is present; if it is negative, the person was exposed but is not currently infected. Hepatitis C often causes no symptoms for years, so screening is important — recommended widely for adults and for people with risk factors. The reason this test matters so much today is that hepatitis C is now curable in the large majority of people with a short course of well-tolerated antiviral tablets, so finding it opens the door to a cure. This is a supportive, non-judgemental test.

• Positive (reactive) — exposure to hepatitis C — the person has been in contact with the virus at some point.
• A current active infection — confirmed only if the follow-up HCV RNA (viral load) is also positive.
• A past, cleared or cured infection — the antibody stays positive for life even though the virus is gone; the RNA is negative.
• Read with liver tests — ALT and AST may be raised in active infection but can be normal.

• Negative (non-reactive) — the expected result; no evidence of exposure to hepatitis C.
• Very early after exposure — the antibody can take weeks to appear, so a very recent exposure may not yet show; a direct virus (RNA) test is used if recent exposure is suspected.