What does a reactive Hepatitis C (HCV) antibody test result indicate?

What Does a Reactive Hepatitis C Antibody Test Mean?

A reactive Hepatitis C antibody test means that antibodies to HCV have been detected in your blood, indicating one of three possibilities: current HCV infection, past resolved infection, or a false-positive result—and you must proceed immediately to HCV RNA testing to determine if you have active infection. 1

Understanding the Test Result

A reactive (or "positive") HCV antibody test does NOT by itself confirm that you currently have hepatitis C infection. 1, 2 The antibody test only tells us that your immune system has encountered the hepatitis C virus at some point, but it cannot distinguish between:

• Current active infection (virus still present in your blood)
• Past resolved infection (you cleared the virus spontaneously or through treatment, but antibodies remain)
• False-positive result (the test incorrectly detected antibodies that aren't really there) 1

Critical Next Step: HCV RNA Testing

You must have HCV RNA testing performed to determine your actual infection status. 1, 2 This is not optional—it is the required next step in the diagnostic algorithm. 1

Interpreting Combined Results:

• HCV antibody reactive + HCV RNA detected = You have current, active hepatitis C infection and need medical evaluation for treatment 1, 2

• HCV antibody reactive + HCV RNA NOT detected = You do NOT have current infection; this represents either past resolved infection or a false-positive antibody test 1, 2

Understanding False-Positive Results

False-positive HCV antibody results are surprisingly common, particularly in low-risk populations. 1 In populations with low HCV prevalence (such as general population screening, healthcare workers, or blood donors), approximately 35% of reactive antibody tests are false-positives (ranging from 15-60%). 1 Even among immunocompromised populations like hemodialysis patients, about 15% of reactive results are false-positives. 1

This is why you cannot rely on the antibody test alone—the high false-positive rate makes confirmatory HCV RNA testing essential. 1

If HCV RNA is Not Detected

When your HCV antibody is reactive but HCV RNA is not detected, no further action is required in most cases. 1, 2 You do not have active hepatitis C, you are not infectious to others, and you do not need treatment. 2

Exceptions Requiring Follow-Up RNA Testing:

You should have repeat HCV RNA testing only in these specific situations: 1, 2

• Recent exposure: If you may have been exposed to HCV within the past 6 months (antibodies and RNA may not yet be detectable in very early infection) 1
• Clinical symptoms: If you have signs or symptoms suggesting active liver disease 1, 2
• Immunocompromised status: If you have weakened immunity, as antibody responses may be delayed or absent 1
• Specimen handling concerns: If there are questions about how the blood sample was stored or processed 1

Important Clinical Considerations

If you had past HCV infection that resolved, you can be reinfected if exposed again—HCV antibodies do not provide protective immunity. 2 This is particularly important for people with ongoing risk factors such as injection drug use.

The window period matters: In the first 1-2 weeks after HCV exposure, HCV RNA may be detectable before antibodies develop. 1 Rarely, antibody development can be delayed for months. 1 In immunocompromised patients, antibodies may never develop despite active infection. 1

Summary Algorithm

1. Reactive HCV antibody → Proceed immediately to HCV RNA testing 1, 2
2. If HCV RNA detected → You have active infection; seek medical care for evaluation and treatment 1, 2
3. If HCV RNA not detected → No active infection; no treatment needed; you are not infectious 1, 2
4. Exception: Repeat RNA testing only if recent exposure, symptoms, immunocompromised, or specimen concerns 1, 2