Testing
What tests are performed on donated blood?
After blood has been drawn, it is tested for ABO group (blood type) and Rh type (positive or negative), as well as for any unexpected red blood cell antibodies that may cause problems in a recipient. Screening tests also are performed for evidence of donor infection with hepatitis B and C viruses, human immunodeficiency viruses HIV-1 and HIV-2, human T-lymphotropic viruses HTLV-I and HTLV-II, and syphilis. The FDA is allowing national deployment of investigational nucleic acid amplification tests (NAT) to screen blood for West Nile virus (WNV) genetic material — an approach similar to that taken for NAT to detect HIV and HCV.
The specific tests currently performed are listed below:
- Hepatitis B surface antigen (HBsAg)
- Hepatitis B core antibody (anti-HBc)
- Hepatitis C virus antibody (anti-HCV)
- HIV-1 and HIV-2 antibody (anti-HIV-1 and anti-HIV-2)
- HTLV-I and HTLV-II antibody (anti-HTLV-I and anti-HTLV-II)
- HTL – human T-cell lymphotrophic virus antibody
- Serologic test for syphilis
- Chagas ELISA antibody test – Click here for more information on Chagas
- Nucleic Acid Amplification Testing (NAT)
Nucleac Acid Testing
NAT employs testing technology that directly detects the genetic material of viruses. Because NAT detects a virus’s genetic material — instead of waiting for the body’s response, the formation of antibodies, as with many current tests — it offers the opportunity to reduce the window period during which an infecting agent is undetectable by traditional tests, thus further improving blood safety.
NAT (Nucleic Acid Testing) is being used to detect:
- HIV-1 and HCV
- West Nile Virus
- Other possible test
- Cytomegalovirus (CMV) antibody -This test is performed to find CMV-negative products as ordered by transfusing hospital per patients’ need. A need might be a newborn infant. Not performed on all donations.
The tests above are performed on donated blood, after the donor has met all the donor history requirements according to Mississippi Blood Services policies and procedures. Medical Director, or FDA and/or AABB-approved variances may apply. These tests have been approved by the U.S. Food and Drug Administration for screening donated blood to lessen the risk of certain transfusion-transmitted infections. Some tests may differ substantially from their similarly-named clinical diagnostic counterpart. False positive tests are possible when screening healthy adults. These tests are not intended for patient diagnosis. The physician of a donor with abnormal (repeat reactive) tests on their donated blood, should follow-up their donor-patient with appropriate clinical diagnostic medical history and physical examination, and clinical diagnostic testing as indicated.