Testing for HCV Infection

Jane P. Getchell, DrPH; Kelly E. Wroblewski, MPH; Alfred DeMaria Jr, MD; Christine L. Bean, PhD; Monica M. Parker, PhD; Mark Pandori, PhD; D. Robert Dufour, MD; Michael P. Busch, MD, PhD; Mark E. Brecher, MD; William A. Meyer, PhD; Rick L. Pesano, MD, PhD; Chong-Gee Teo, MD, PhD; Geoffrey A. Beckett, MPH; Aufra C. Araujo, PhD; Bernard M. Branson, MD; Jan Drobeniuc, MD, PhD; Rikita Hatia, MPH; Scott D. Holmberg, MD, MPH; Saleem Kamili, PhD; John W. Ward, MD

Disclosures

Morbidity and Mortality Weekly Report. 2013;62(18):362-365. 

In This Article

Recommended Testing Sequence

The testing sequence in this guidance is intended for use by primary care and public health providers seeking to implement CDC recommendations for HCV testing.[1,3,4] In most cases, persons identified with HCV viremia have chronic HCV infection. This testing sequence is not intended for diagnosis of acute hepatitis C or clinical evaluation of persons receiving specialist medical care, for which specific guidance is available.[12]

Testing for HCV infection begins with either a rapid or a laboratory-conducted assay for HCV antibody in blood (Figure). A nonreactive HCV antibody result indicates no HCV antibody detected. A reactive result indicates one of the following: 1) current HCV infection, 2) past HCV infection that has resolved, or 3) false positivity. A reactive result should be followed by NAT for HCV RNA. If HCV RNA is detected, that indicates current HCV infection. If HCV RNA is not detected, that indicates either past, resolved HCV infection, or false HCV antibody positivity.

Figure.

Recommended testing sequence for identifying current hepatitis C virus (HCV) infection
* For persons who might have been exposed to HCV within the past 6 months, testing for HCV RNA or follow-up testing for HCV antibody is recommended. For persons who are immunocompromised, testing for HCV RNA can be considered.
To differentiate past, resolved HCV infection from biologic false positivity for HCV antibody, testing with another HCV antibody assay can be considered. Repeat HCV RNA testing if the person tested is suspected to have had HCV exposure within the past 6 months or has clinical evidence of HCV disease, or if there is concern regarding the handling or storage of the test specimen.

Initial Testing for HCV Antibody

An FDA-approved test for HCV antibody should be used. If the OraQuick HCV Rapid Antibody Test is used, the outcome is reported as reactive or nonreactive. If a laboratory-based assay is used, the outcome is reported as reactive or nonreactive without necessarily specifying signal-to-cutoff ratios.

Testing for HCV RNA

An FDA-approved NAT assay intended for detection of HCV RNA in serum or plasma from blood of at-risk patients who test reactive for HCV antibody should be used. There are several possible operational steps toward NAT after initial testing for HCV antibody:

  1. Blood from a subsequent venipuncture is submitted for HCV NAT if the blood sample collected is reactive for HCV antibody during initial testing.

  2. From a single venipuncture, two specimens are collected in separate tubes: one tube for initial HCV antibody testing; and a second tube for HCV NAT if the HCV antibody test is reactive.

  3. The same sample of venipuncture blood used for initial HCV antibody testing, if reactive, is reflexed to HCV NAT without another blood draw for NAT.[13]

  4. A separate venipuncture blood sample is submitted for HCV NAT if the OraQuick HCV Rapid Antibody Test for initial testing of HCV antibody has used fingerstick blood.

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