Hepatitis C Lookback

Hepatitis C lookback is part of a public health effort to alert persons who may have been exposed to hepatitis C virus (HCV) through blood transfusions before July 1992 in order that they may obtain further medical counseling, including treatment if indicated. "Lookback" is a term first coined in the late eighties, referring to notification of recipients of untested blood components from donors who were later found to be HIV-positive after the test for antibody to HIV was implemented in March, 1985. 

Over 60 percent of HCV infections in the USA today have been acquired through injecting drug use. Blood transfusion, which accounted for a substantial proportion of HCV infections acquired over 10 years ago, rarely accounts for recently acquired infections¹.

Screening of blood donations for antibody to hepatitis C was first implemented in the USA in May 1990. Almost half of donors with positive results by this 'first generation' screening test were later shown to be falsely positive based on supplemental testing with more specific tests (see RIBA, below). In July 1992, a more sensitive screening test (using multiple antigens), along with availability of a licensed supplemental test (RIBA - RecombinantImmunoBlot Assay) enabled a more confident determination of HCV status in blood donors. As a result of these and other measures implemented between the early 1970's and the present, the risk that a unit of blood might transmit HCV has fallen from over 20 percent in the early 1960's (studies in heart surgery patients at the NIH)  to approximately 1 in 100,000 today.

Notification or recipients will be broad-based, taking into account the fact that HCV has been around for a long time and many patients received untested blood from donors who stopped donating before July 1992. Therefore, in addition to "targetted" lookback as described below, there will be a nationwide educational campaign directed at physicians and the general public to identify and encourage testing of all patients who received blood transfusions before July 1992. Also, since some patients are unsure or unaware of having received a blood transfusion, an effort will be made to include them through a history of blood disorder, major surgery or trauma, bleeding during delivery, or premature birth.

Targetted (Directed) Lookback

Identification of recipients of blood from donors subsequently found to be positive for HCV after July 1992* depends on whether the donor had previous untested donations, or after this date seroconverted from negative to positive.

• Previous untested donations - Because most persons with hepatitis C remain asymptomatic for many years, notification is recommended for recipients of blood components from untested donations made since January 1988.

• Seroconversion after July 1992 - Because the maximum ("window") period before seroconversion is 12 months, recipients of donations up to 12 months before the most recent negative screening test will be notified.

* After a recommendation to extend lookback to recipients of blood from donors testing positive on an earlier (but less accurate) version of this test ("anti-HCV EIA version 1.0") which was implemented in May, 1990, the FDA has indicated they will review the recommendation and issue a 'Guidance to Industry' soon.  Upon receipt, blood centers will amend their lookback procedures accordingly.

Notification process

Blood center records of product distribution generally contain information only about the hospital consignee. Therefore, after blood centers review their records and identify affected components from previous donations, they will notify the hospital, providing them with appropriate materials to assist in physician and patient notification. After the hospital searches their records and identifies the recipient, they will notify the attending physician who (possibly supported by local infectious disease staff or other resources) will be responsible for notification and initial counseling of the patient, including a recommendation to be tested for hepatitis C. Blood samples sent to the American Red Cross will be tested at no charge.

Guidelines for Patients with Positive Test Results

A result is considered positive if both the enzyme immunoassay (EIA) and the supplemental RIBA test are positive for antibody to hepatitis C.

Patients with positive results should be counseled about hepatitis C, guided by informational materials that will be provided. They should also be evaluated further by a physician knowledgeable in hepatology to test for viral RNA, and to assess the severity of hepatitis and the advisability of antiviral therapy.

General counseling should include:

• Inquiry about other (more common) sources of HCV (sharing of needles used for illegal drug injection, multiple sexual partners, blood contact through occupational exposure, hemodialysis, etc.)

• Advice about measures to protect their liver from further harm:

• Advice to reduce the risk of spread to others through contact with their blood
• The risk of sexual spread is very low, but not absent
• Advice about pregnancy and breastfeeding
• Reassurance that usual household, social and occupational contacts do not spread HCV
• Referral to local support groups and other resources

Cherie S. Evans, MD
J. Lawrence Naiman, MD

References:

1. CDC. Recommendations for Prevention and Control of Hepatitis C Virus (HCV) and HCV-related Chronic disease. MMWR 1998:47(No. RR-19): 1-39 (Oct. 16). A single copy is available from the CDC national Prevention Information Network (NPIN) by calling 1-800-458-5231. Also, it may be downloaded from the CDC's MMWR website.
2. FDA Guidance for Industry. Current Good manufacturing Practice for Blood and Blood Components: (1) Quarantine and Disposition of Units from Prior Collections from Donors with Repeatedly Reactive Tests for Antibody to hepatitis C Virus; (2) Supplemental Testing, and the Notification of Consignees and Blood recipients of Donor test results for Anti-HCV
3. CDC Website on Hepatitis C. For general information, including materials for patients.

Last updated: Nov 30, 2000