While blood transfusion is, in many respects, safer than it has ever been, the risks associated with transfusion are still present and must be evaluated against the benefit provided by transfusion.

The following information has been compiled to provide both current infectious risks and non-infectious risks of blood transfusion. References to support this information are given at the bottom.

Infectious Risks of Blood Transfusion, 2007 to 2012

Parvovirus B19 (erythrovirus) Unknown; about 12 cases reported in the literature
Babesia 1:20,000
Bacteria (platelets) 1: 5,000 (tested)
Bacteria (RBCs) 1:500,000
Hepatitis A virus 1:1 million
Hepatitis B virus 1:850,000 to 1:2 million
Hepatitis C virus 1:1,150,000
HIV (Human Immunodeficiency virus) 1:2 million
Human T-lymphotrophic virus 1:200,000 to 1:500,000
Malaria 1:1,000,000
West Nile virus Unknown but varies by season; about 11 cases reported in the literature since 2003


Non-infectious Risks of Blood Transfusion, 2007 to 2012

Adverse Outcome Risk Per Unit Transfused Clinical Signs & Symptoms
Acute hemolytic 1:40,000 to 1:70,000 Chills, fever, pain at infusion site, hemoglobinuria, shock, acute renal failure, flank pain, DIC
Allergic - simple 1:100 to 3:100 Flushing, hives, itching
Allergic  - severe 1:20,000 to 1:50,000 Hypotension, respiratory distress, wheezing, local edema
Transfusion associated circulatory overload (TACO) 1:100 to 11:100 Dyspnea, hypertension, pulmonary edema
Delayed hemolytic 1:5,000 to 1:11,000 Drop in hemoglobin, increased indirect bilirubin, new RBC antibodies
Febrile non-hemolytic 1:100 (prestorage leukoreduced products) Fever with greater than 1°C change, chills, rigors
Graft versus host disease Rare Rash, diarrhea, hepatitis, pancytopenia
Transfusion-related acute lung injury (TRALI) 8:100,000 Hypoxemia, dyspnea, hypotension, non-cardiogenic pulmonary edema



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