Risks and prevention of infections

Multiple transfusions of a pooled plasma product such as Factor VIII poses a high risk of acquiring infections:

• approximately 60 % of the haemophiliac population were exposed to HIV - 1 before this risk was recognised
• there is evidence of prior hepatitis B infection in many older haemophiliacs
• approximately 75% of haemophiliacs have antibodies to hepatitis C virus - 50% of whom will develop evidence of chronic liver disease

Steps taken to reduce the risk of infection include:

• vaccination against hepatitis B virus in all newly diagnosed haemophiliacs
• screening of plasma donors for hepatitis and HIV virus infection
• routine sterilisation of all forms of Factor VIII concentrates except for cryoprecipitate - by heat or solvent / detergent
• viral inactivation methods - for hepatitis virus
• cryoprecipitate carriers a lower risk of infection than other forms of Factor VIII because fewer donors are involved - but methods for routine treatment of this blood component are not yet available
• use of non-blood products such as DDAVP (a synthetic vasopressin) and/or tranexamic acid (anti-fibrinolytic) may preclude need for blood products - suitable only for mild or moderately affected haemophiliacs