Testing Donor Blood
Each dose of blood donated
- is assigned a donor blood type in various systems (AB0, RhD and Kell)
- is screened for antibodies and
- four blood-borne diseases: hepatitis B, hepatitis C, syphilis and HIV.
First-time donors can learn their blood type in the ABO system at the first visit as it is determined at a quick medical check and later verified in the lab. RhD is determined only in a laboratory and the donor can find this information the second time they come in to give blood.
Before giving blood, the donor’s haemoglobin level is also determined from a drop of blood from the fingertip. The normal range for haemoglobin is
- 125-165g/l for women
- 135-180g/l for men
If necessary, the donor’s blood pressure and pulse are measured, and the normal range is:
- blood pressure 100/60-180/100 mmHg
- pulse 50-100 bpm
Analysis conducted after each donation:
- Hepatitis B virus surface antigen (HBsAg)
- Hepatitis B virus DNA (HBV DNA)
- Hepatitis C virus antibodies (Anti-HCV)
- Hepatitis C virus RNA (HCV RNA)
- Anti-HIB antibodies (Anti-HIV-1,2) and antigen (HIV p24)
- HIV RNA
- Syphilis
Donor blood testing is in line with European Union directives and the laws of the Republic of Estonia. A big step forward was taken in 2007 – the test for HIV antigen was replaced with molecular biological examination of HIV – the HIV RNA PCR test, which is the most sensitive and state of the art method in modern viral diagnostics. The window period for this method is just 8-12 days. Assaying for HIV RNA provides the maximum level of safety of donor blood.
All tests for viruses in donor blood are automated and performed using the testing systems of internationally recognized companies. The results of the tests are transferred directly from the testing equipment to the Estonian Blood Service Information System (EVI). The Blood Centre is unable to release to hospitals blood components that have not been subjected to testing or returned positive results as EVI does not permit this.
If analysis results require follow-up checks, the donor is called in for repeat testing. Blood in which an infectious disease agent is found is destroyed.