At the BBC site today: "Both the US and Canadian governments have imposed a ban on blood donations from anyone who has lived in or frequently visited Britain over the last 19 years. The ban reflects concern about the possibility that mad cow disease might be transmitted to humans in the form of CJD through tainted blood." "Medical researcher Peter Lurie, one of the doctors advising the US Food and Drug Administration, said: "We are dealing with a disease that may still be on the increase in terms of human disease, we are dealing with an organism that we cannot identify, and we are dealing with a disease that only causes symptoms several years after it is first transmitted. 'All of those things argue in favour of more caution'." http://news.bbc.co.uk/hi/english/health/newsid_423000/423344.stm