Blood transfusions

Whether or not you can acquire CJD from a transfusion of blood or blood products is controversial. You are highly unlikely to catch classical CJD through blood and blood products, but there have been several cases where variant CJD has been transmitted.

Because no test exists yet for CJD that could be used to screen blood donors and to protect the blood supply, most governments require blood banks to screen for risk factors and prohibit donations from high-risk individuals (those who have received human pituitary growth hormone or a dura mater (brain covering) transplant, lived in England during the BSE epidemic, a blood relative with CJD, etc.). These improvements in screening and education seem to have maintained a safe blood supply. Governments and blood banks reevaluate public health policies on CJD and blood safety as scientific discoveries are made.