Percentage of donated blood units screened for HIV in a quality-assured manner
To assess progress in screening of blood donations in a quality-assured manner.
Blood safety programmes aim to ensure that all blood units are screened for transfusion-transmissible
infections, including HIV, and that only those units that are non-reactive on screening tests are released
for clinical use. In many countries, blood units are not screened for all the major transfusion-transmissible infections. Often, even when screening does occur, the safety of blood is compromised by inaccurate test results due to the poor quality or incorrect storage of test kits. Furthermore, inadequate staff training or a lack of standard operating procedures may result in laboratory errors. This could lead to blood units being classified as safe even when they are infectious, posing a serious risk of transmission of HIV through unsafe blood.
Universal (100%) screening of donated blood for HIV and other transfusion-transmissible infections
cannot be achieved without mechanisms to ensure quality and continuity in screening. In some countries, interruptions to supplies of test kits and reagents, or emergency situations, can result in the use of blood for transfusion without screening for transfusion-transmissible infections. The development of systems for reliable and regular supplies of low-cost, high-quality test kits and reagents and effective stock management are therefore essential to ensure universal quality screening of blood units.
Thus, it is crucial that all donated blood units be screened for HIV in a quality-assured manner. The
following methodologies are two key components of quality assurance in screening.
1. The use of documented and standardized procedures (standard operating procedures) for the
screening of every blood unit.
2. Participation of the laboratories in an External Quality Assessment Scheme for HIV screening in
which external assessment of the laboratory’s performance is conducted using samples of known, but
undisclosed, content to assess its quality system and assist in improving standards of performance.
Number of donated blood units screened for HIV in a quality assured manner. For the purposes of data collection screening in a quality assured manner if defined as screening performed in blood centres/
blood screening laboratories that (i) follow documented standard operating procedures and (ii) participate in an external quality assurance (EQA) scheme
Total number of blood units donated.
In this context, donation refers to any blood collected for the purposes of medical use. This includes all possible types of providers of blood, regardless of whether they receive remuneration or not.
If the blood screening laboratory follows documented and standardized procedures for the screening of
blood, this implies a certain level of uniformity, reliability and consistency of performance by staff trained
to use the standard operating procedures. If a blood screening laboratory participates in an External
Quality Assurance Scheme, this implies that the quality of HIV screening performed is being assessed at regular intervals. It is important to view the percentage of screened blood units in relation to these two
basic components of quality as both are required to ensure the quality of procedures.
Countries provide data to the WHO Global Database on Blood Safety on this indicator annually. Locally,
these data can be obtained by contacting the National Blood Transfusion Service, the National Blood
Programme and/or the National AIDS Programme.
