If you live in UK you cant give blood AS anyone asked why.
6 Factors That Mean You Can't Donate Blood.
And bottom of list is People who have spent long periods of time in countries where "mad cow disease" is found, such as Great Britain, are also not eligible to donate, regardless of how long they have been away from it.
Bet UK gov don't tell tourist visating uk that little snipit.
Anyway i thought blood products was sterolised SO why can't those with tierd immunty have transfusion immunty imported.