Inactivation of viruses, bacteria, protozoa, and leukocytes in platelet concentrates: Current research perspectives

Abstract

LTHOUGH increased safety of blood components has been achieved through continued improvements in donor testing, concern remains about the safety of blood products. A recent government report estimated that 2.7 of every 1,000 patients who receive a transfusion of 5 units of blood components are at risk of acquiring an infectious disease. 1 Currently, prevention of infectious disease transmission associated with the transfusion of cellular components rests largely on pretransfusion donor evaluation and laboratory testing. Despite improvements in testing, the aggregate risk of acquiring a viral infectious disease from a donor passing all current serological testing remains 1 per 34,000 donbr exposures. 2 Transfusion of cellular components has been implicated in transmission of viral, bacterial, and protozoan diseases. 3 Although it is commonly recognized that hepatitis B virus (HBV), hepatitis (2 virus (HCV), cytomegalovirus (CMV), and the retroviruses, such as human immunodeficiency virus (HIV) and the human lymphotrophic viruses (HTLV), can be transmitted through cellular components, other pathogens are emerging as potentially significant transfusion-associated infectious agents. For example, transmission of protozoan infections attributable to trypanosomes 4-6 and babesia have been reported. 7,8 In addition to viral and protozoal infectious agents, bacterial contamination o f platelet concentrates continues to be reported 9,1~ and may be underreported. 11 More importantly, new infectious agents, for example, hepatitis G virus, may enter the donor population long before tests adequate to maintain consistent safety of the blood supply can be implemented. 12 Even when identified early, the clinical significance of new pathogens may not be fully recognized until large epidemiological studies are completed. 13 Over the past 10 years, investigation of methods for inactivation of infectious pathogens in cellular