It turns out that the blood drive takes place in the building I work in. So I go. They make me fill out a one page densely written form, asking for all kinds of illnesses and drugs I took and take. It includes a question on having been or having lived abroad for longer periods of time. Sure I have, I just arrived from Switzerland. So the box gets ticked. Sign it and walk over to the nurse with the big needle in her hands.
I hand her the form and she goes "Oh. When did you live abroad and when did you arrive here?" I tell her that I arrived just about a month ago. She shakes her head and walks over to a colleague, me right behind her. The colleague confirms her suspicion. They thank me for my initiative and inform me that they don't accept European blood donations due to possible infection with Creutzfeld-Jakob, better known as the mad cow disease.
They feel sorry for me, hand me the lunch voucher and the scarf as a present. I leave the place with an odd feeling of having some inferior blood running down my veins.
P.S.: Some further investigation with the nurse reveals that this is actually a guideline issued by the FDA, the US Food and Drug Administration that oversees blood donations. I checked the FDA Internet pages and indeed found the document. Read the original reference or the document that I downloaded on February 7, 2003, from the FDA pages (http://www.fda.gov/cber/gdlns/cjdvcjd0602.htm), in particular the "recommendations for donor eligibility" towards the end.