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nvCJD

I haven't seen any stories on this in a long time and went searching since I still can't donate blood because of my stay in Germany in 1986...

http://www.cjd.ed.ac.uk/figures.htm

The numbers for 2000 -> 2010

28, 20, 17, 18, 9, 5, 5, 5, 1, 3, 3

This is for the UK, because the US has had 3 total cases of vCJD, 2 of whom were from the UK, one was from Saudi Arabia..

http://www.cdc.gov/ncidod/dvrd/vcjd/factsheet_nvcjd.htm

This is probably directly related to the recession we are in. It seems to have peaked during the boom years...

My eyesight says that the correlation between nvCJD and the recession is really tight...

Re: nvCJD

Interestingly, in Austria anyone who spent a total of more than 6 months in Great Britain between 1980 and 1996 is permanently banned from donating blood. The Austrians also ban homosexual men (but not homosexual women) and current and former drug abusers but don't ban current or former prostitutes.

To be fair, I think this is one of those cases where the precautionary principle applies (within reason), and there is some history thrown in. There are tens of thousands of people infected with Hepatitis C through blood transfusion, from the time before the disease was identified (1990 IIRC). Even after that it proved difficult to test blood for the agent, which is highly infectious, remarkably easy to pick up, and for which perhaps 90% of carriers are unaware they have the disease. In the west, at least 1 in 100 are infected, in some places 1 in 30. Hep C will be bigger than HIV, and not helped by the health services helping to infect rather a large proportion of their client base. A repeat of the hep c scandal is not what anyone wants, and provided the precautions don't unduly restrict supply, there is no problem.

Most blood products are produced by pooling from large numbers of donors. This particularly affects products such as clotting factors, which are present in tiny amounts but which are required in relativelyl large quantities by those deficient. A single treatment could contain blood from hundreds of donors, multiplying the infection risk.

vCJD, assuming we are convinced it really exists and is something new, is clearly blood-borne and we still don't know for sure what the effects are. We also don't know how specific and sensitive the tests for it are. It could simply have a long median incubation period (analogous to Hep C which can take 30 years to become symptomatic). Fortunately, it looks like it is actually far more difficult to catch than Hep C, but what is the point in taking the risk of getting more infectious agent than necessary into the blood derivatives supply chain? There is no major shortage of blood products, if there were then you would take the risk of widening the donor pool. If there was a glut, you might narrow it further.

Re: nvCJD

When I have talked to Red Cross people, they have told me that the blood supply in the US is typically about 3 days. Their hands are tied by "Crying wolf" syndrome.

That information is purely anecdotal of course, but I have heard it from multiple sources.

Re: nvCJD

So supply of blood is adequate and well-matched with demand.

Re: nvCJD

As long as you deem well matched to mean managers of the supply constantly biting their nails hoping that no disasters happen. They would prefer the number to be 5-6 days instead of 3.

Re: nvCJD

I'm surprised you're having to use anecdotal information about the number of days of blood supply available in the USA, Brad. After a bit of Googling I found this webpage by some organisation called "America's Blood Centers" which supplies half of the USA's volunteer donor blood.

link

It looks like there could be some US blood centres that have only 1 day supply or less, and a few more that have only 2 days supply. The colour coding system used for the supply situation at the blood centres, which specifies green for 3 days or more supply, suggests that 3 days supply is regarded as acceptable.

If there was a disaster, I would imagine it wouldn't be difficult to get a lot of blood donors to come forward at short notice.

Re: nvCJD

Silly me, didn't think they would be advertising. Yet the first one on the list (Ohio) shows almost no O- blood. O- is relatively rare, but it is on the edge of not being there. On the same page of query, I saw 3 postings for "critical levels" dated today.

It is nice to know that my blood type seems to be relatively available though. I guess I shouldn't fret too much.