Tests for Transmissible Diseases

Many processes are used to prevent disease transmission via donated blood. These include the following screening procedures:

• blood donor eligibility standards
• pre-donation information pamphlet
• pre-donation questionnaire (record of donation)
• pre-donation interview
• pre-donation blood pressure & temperature
• confidential unit exclusion
• verification of records of previous donations
• laboratory screening tests

Also see donor criteria.

Laboratory Screening Tests

CBS uses laboratory tests to screen every donation for transmissible diseases. PRISMTM, Abbott's high-volume immunoassay analyzer, is used for transmissible disease testing.

See detailed TD tests on the blood.ca site and Further Reading for additional information.

Reactive results

Any samples that are reactive with the screening tests are subject to more specific supplemental assays or confirmatory tests and the blood is not used for transfusion. Donors are contacted by letter if a test is reactive, regardless of the confirmatory result. With the donor's consent the information is forwarded to their physician for appropriate follow-up, if necessary. Test results are kept confidential.

CBS conducts lookback studies on donors with confirmed positive tests for HCV and HIV.

Donors may be temporarily, indefinitely, or permanently excluded from donating blood, either because of their health history or because of test results. Where required by provincial law, positive results are reported, in confidence, to the public health authorities who investigate appropriately.

Also see information on false positives on the bloodservices.ca site

Further Reading - Transmissible Diseases

Transmissible disease screening

1. Busch MP. HIV, HBV and HCV: new developments related to transfusion safety. Vox Sang 2000;78 Suppl 2:253-6.
2. Canadian Blood Services. Safety is Paramount: NAT.
3. CBER, FDA (USA). Draft guidance for industry use of nucleic acid tests on pooled and individual samples from donors of whole blood and blood components for transfusion to adequately and appropriately reduce the risk of transmission of HIV-1 and HCV. (Draft posted: 2002-03-11; for comment only)
4. Dodd RY, Stramer SL. Indeterminate results in blood donor testing: what you don't know can hurt you. Transfus Med Rev 2000 Apr.;14(2):151-60.
5. Fischer G, Hoots WK, Abrams C. Viral reduction techniques: types and purpose. Transfus Med Rev 2001 Apr.;15(2 Suppl 1):27-39. [ Medline ]
6. Holland PV. Old and new tests: where will it end? Vox Sang 2000;78 Suppl 2:67-70.
7. Hoots WK, Abrams C, Tankersleydagger D. The impact of Creutzfeldt-Jakob disease and variant Creutzfeldt-Jakob disease on plasma safety. Transfus Med Rev. 2001 Apr.;15(2 Suppl 1):45-59. [ Medline ]
8. Kleinman S. Hepatitis G virus biology, epidemiology, and clinical manifestations: Implications for blood safety. Transfus Med Rev. 2001 Jul.;15(3):201-12. [ Medline ]
9. Morgenthaler JJ. Securing viral safety for plasma derivatives. Transfus Med Rev 2001 Jul.;15(3):224-33. [ Medline ]
10. Orton S. Syphilis and blood donors: what we know, what we do not know, and what we need to know. Transfus Med Rev 2001 Oct.;15(4):282-91. [ Medline ]
11. Orton SL, Dodd RY, Williams AE; ARCNET Epidemiology Group. Absence of risk factors for false-positive test results in blood donors with a reactive test result in an automated treponemal test (PK-TP) for syphilis. [ Full text ] [ Medline ]
12. Roth WK, Buhr S, Drosten C, Seifried E. NAT and viral safety in blood transfusion. Vox Sang 2000;78 Suppl 2:257-9.

Transmissible diseases - lookbacks

1. Goldman M, Long A. Hepatitis C lookback in Canada. Vox Sang 2000;78 Suppl 2:249-52. [ Medline ]
2. Goldman M, Spurll G. Hepatitis C lookback. Curr Opin Hematol 2000 Nov.;7(6):392-6. [ Medline ]
3. Stramer SL, ed. Blood Safety in the New Millennium. Bethesda, MD: American Association of Blood Banks, 2001.