Bacterial contamination in blood components and preventative strategies: an overview

Bacterial contamination of blood and its cellular components remains an unresolved problem in transfusion medicine and is considered to be the most common microbiological cause of transfusion associated morbidity and mortality. This is because contaminated units may contain large numbers of virulent bacteria as well as endotoxins that are considered to be fatal to the recipient. Accordingly, measures have been proposed to prevent or at least control the potential risk of transfusion associated bacteria infections. Broadly, these approaches include: bacterial avoidance; bacterial growth inhibition and bacterial load reduction by leucofiltration/viral inactivation. Unfortunately, none of the current approaches alone or in combination have received overall acceptance in terms of operational practice and safety/efficacy. Considerable effort has also been directed towards improving bacterial detection in order to provide a scientific basis for the lengthening of the shelf life of liquid stored platelets, without affecting, to a large extent their safety/efficacy. These issues have been highlighted in this overview on the current status and future trends.