Evidence from:
HPA Centre for infections
“Report of Seminar on Ethical and Social Aspects of Testing for vCJD”
Current practice includes no right to opt out of such information; potential donors found to be reactive to blood tests for vCJD should therefore be informed of their test result. The wording on the consent form is “I understand that if my donation gives a positive result for any of [the listed] tests I will be informed and asked to attend for further confirmatory tests and advice.”
Further detail: