| Viruses |
| Hepatitis Hepatitis A virus (HAV) Hepatitis B virus (HBV) Hepatitis C virus (HCV) Hepatitis D virus (HDV) Hepatitis E virus (HEV) Hepatitis G virus (HGV) Cytomegalovirus (CMV) Epstein–Barr virus (EBV) |
| Nonhepatitis |
| Bacteria Yersinia Pseudomonas Staphylococcus Other gram-positive or gram-negative bacteria Rickettsia Spirochetes |
| Protozoa |
| Plasmodium spp. (malaria) Babesia microti Babesia spp. Trypanosoma cruzi (Chagas disease) Toxoplasma spp. Leishmania spp. Nematode (loasis, other microfilaria) Treponema pallidum (syphilis) |
Abbreviations: HIV = human immunodeficiency virus; HTLV = human T-cell lymphoma/leukemia virus.
a Potential risk only, no reported case.
Although the rate of bacterial contamination of blood products is unknown, the rate of bacterial infection associated with blood products is estimated to be similar to that of viral infection. The Bacterial Contamination of Blood Products (BaCON) study, a collaboration among the Centers for Disease Control and Prevention (CDC), American Red Cross, American Association of Blood Banks (AABB), and Department of Defense, conducted active surveillance for transfusion-transmitted bacteremia between 1998 and 2000. There were 34 bacteremic episodes and 9 deaths. The rate of transfusion-transmitted bacteremia (events per 106 units) was 9.98 for single-donor platelets, 10.64 for pooled platelets, and 0.21 for red blood cell units; for fatal reactions, the rates were 1.94, 2.22, and 0.13, respectively. The fatality rate associated with transfusion-related sepsis has been estimated to be 1 in 6 million transfused units. Transfusion-transmitted bacterial sepsis is the second most common cause of transfusion-related fatality (after clerical error). Between October 1995 and September 2004, 85 (13%) of 665 transfusion fatalities reported to the Food and Drug Administration were due to bacteria; 58/85 (68%) were due to gram-negative bacteria. In 2008, there were approximately 24 million blood components transfused. During FY2008, there were 46 FDA-reported transfusion-related fatalities, with subsequent reports of 44 in FY2009, 40 in FY2010, and 30 in FY2011. Of these, 5 (11%), 2 (5%), and 4 (13%) in FY 2009, FY2010, and FY2011, respectively, were traced to microbial infection. In FY2010 and FY2011, Babesia, Staphylococcus aureus, Escherichia coli, Morganella morganii, and Klebsiella pneumoniae accounted for all the fatalities. However, more common nonfatal episodes of transfusion reaction, which may result from bacterial contamination of blood or blood components, often are assumed to be an immune response to transfused leukocytes and are not fully investigated for contamination.
Whole blood and erythrocytes
After collection, whole blood may be maintained at room temperature for ≤8 hours before being stored at 1°C to 6°C (33.8°F to 42.8°F) up to 35 to 42 days, depending on the additives used (Table 106.2). Erythrocytes may be prepared from whole blood at any point during the normal storage period of the whole blood. Then, the erythrocytes may be stored at 1°C to 6°C up to the expiration date of the whole blood unit from which they were prepared. The growth of psychrophilic organisms, such as Yersinia enterocolitica or Pseudomonas species, is favored by these storage conditions, accounting for most erythrocyte transfusion-related sepsis episodes (Table 106.3). These episodes tend to occur with units that have been stored for >14 to 25 days, which reflects a growth lag of about 7 to 14 days followed by exponential growth of the organism; levels of 109 organisms/mL are reached by 38 days, and 315 ng of endotoxin/mL (approximately 4000 EU/mL) by 28 to 34 days. Transfusion of such units can lead to both septic and endotoxic shock.
| Component | Storage conditions | Estimated contamination rate |
|---|---|---|
| Whole blood CPDA-1 CPD plus AS | ≤8 h at room temp ≤35 d at 1°C–6°C ≤45 d at 1°C–6°C | 0.03% |
| Packed red blood cells CPDA-1 CPD plus AS | ≤35 d at 1°C–6°C ≤45 d at 1°C–6°C | ≤0.5% |
| Platelets | ≤5 d at 20°C–24°C | Single donor, ≤2.5% Pooled, ≤10% |
