Step 1: Perform an enzyme immunoassay for anti-HCV antibodies.
(1a) If the test is repeatedly reactive, then proceed to step 2.
(1b) If negative, then stop.
Step 2: Perform a more specific assay, either the RT-PCR for HCV RNA or a RIBA test for anti-HCV
(2a) If either is positive, then refer the patient for medical evaluation.
(2b) If the RT-PCR is negative, then perform the RIBA test for anti-HCV. If the RIBA test is positive, then refer for medical evaluation.
(2c) If the RIBA test is negative, then stop.
Step 3: If the RIBA test is indeterminate, then perform RT-PCR and serum ALT.
(3a) If either the RT-PCR or serum ALT is abnormal, then refer for medical evaluation.
(3b) If the RT-PCR is negative AND the ALT is normal, then stop.
(3c) An alternative strategy is to wait 2 or more months and then repeat the RIBA test.