So, for the last 2 weeks, my coworkers have thought I was making shit up when I told them I wasn't eligible to donate blood because of Mad Cow Disease; they thought I just didn't want to give blood.

Quote: redcross.org In-Depth Discussion of Variant Creutzfeld-Jacob Disease and Blood Donation In some parts of the world, cattle can get an infectious, fatal brain disease called Mad Cow Disease. In these same locations, humans have started to get a new disease called variant Creutzfeld-Jacob Disease (vCJD) which is also a fatal brain disease. Scientists believe that vCJD is Mad Cow Disease that has somehow transferred to humans, possibly through the food chain. There is now evidence from a small number of case reports involving patients and laboratory animal studies that vCJD can be transmitted through transfusion. There is no test for vCJD in humans that could be used to screen blood donors and to protect the blood supply. This means that blood programs must take special precautions to keep vCJD out of the blood supply by avoiding collections from those who have been where this disease is found. At this time, the American Red Cross donor eligibility rules related to vCJD are as follows: You are not eligible to donate if: [...] You were [...] a dependent of a member of the U.S. military who spent a total time of 6 months on or associated with a military base in any of the following areas during the specified time frames From 1980 through 1990 - Belgium, the Netherlands (Holland), or Germany

I was born to American parents on an US Army base near Augsburg, Germany in 1982. We didn't move back to the US until after my father finished his enlistment term in 1984 or 1985. It seems sort of a silly restriction. It seems like if I had gotten it some time between age 0 - age 3, I would have seen some kind of symptoms by age 26. If the disease is at all transmissible through blood, shouldn't there be some way to test for it?

There's quite a few things that make you not eligible to give blood here too - I'd like to think that they actually test the blood they get anyway...

The answer is fairly simple. The blood is tested, but tests aren't perfect. (Edit: Should point out that this is for some other reasons of rejection, given that there actually is no test in the case used in this thread)

If you fall into a group that has a high chance of failing a test anyway, you aren't allowed to donate blood. If you have a high chance of your blood failing, then you have a high chance of wasting resources testing your blood. Resources that could have gone toward someone's blood that had a high chance of passing the tests.

Quote: Original post by Evil Steve
There's quite a few things that make you not eligible to give blood here too - I'd like to think that they actually test the blood they get anyway...

Quote: Original post by capn_midnight

Quote:
There is no test for vCJD in humans that could be used to screen blood donors and to protect the blood supply.

Quote: Original post by HostileExpanse

Quote: Original post by Evil Steve
There's quite a few things that make you not eligible to give blood here too - I'd like to think that they actually test the blood they get anyway...

Quote: Original post by capn_midnight

Quote:
There is no test for vCJD in humans that could be used to screen blood donors and to protect the blood supply.

/me learns to read [smile]

I have a friend who hit the 3-month limit, and some others who spent a few years in ineligible countries.

When we have a blood drive around work about 1/3 of the people cannot give blood, including me. (They don't want me giving blood because I tend to pass out. I started passing out after a blood draw where they went searching for blood with the needle and seriously hurt my arm....)


It is rather odd about how strict they are for it, but the blood supply is one of those 'better safe than sorry' situations.

Quote: If the disease is at all transmissible through blood, shouldn't there be some way to test for it?

Yes google Amorfix they claim nearly 100% detection rate.

My wife worked as an epidemiology researcher studying disease transmission for the Canadian Red Cross back before the blood bank was taken away from them for transmitting too much disease and given to the same people but with a different organizational name. She described some of the screening bases to me.

First off, testing is expensive. There are a slew of tests done for each and every donation, and they cost money, money the blood agency(ies) generally do not have a lot of. Often times there is an inexpensive screening test with a high false positive rate and a very expensive test with a low false positive rate. By prescreening donors, the necessity of sending donations for a second, more expensive test is reduced thuis reducing costs without reducing quality of the blood supply.

Secondly, some tests have an unacceptably high false negative rate. Prescreening donors can reduce the probability of receiving false negatives on the tests. There is no such thing as a zero false-negative rate for tests, marketing from drug firms notwithstanding. Most blood products are aggregated, so a single false netagive can infect hundreds of recipients. Better to be safe than sorry.

As to how vCJD works, the onset horizon, and causation, well, really there isn't a lot of scientifically reliable information. Most evidence points towards the prion theory, but no one really knows the transmission route or how long it takes a few prions floating around to start the avalanche of protein misfolding that rots your brain, or why some people seem completely immune. It might take more than a couple of decades before you go vegetable. Tic tic tic tic .....

Mad Cow MacBeth? [grin]

Hospitals sometimes refer to Creutzfeld-Jacob Disease as Kuru. The two diseases are similar but different. At least, when my cousin had back surgery after a car crash it turned up on the bill.

There are some tourist destinations that will render you unfit to give blood as well. Three years ago my father went on a Mediterranean cruise that stopped in Turkey. After he got back he went to give blood only to discover that he wouldn't be able to do so for 6 months. They were worried about malaria.

Quote: Original post by Talroth
The answer is fairly simple. The blood is tested, but tests aren't perfect. (Edit: Should point out that this is for some other reasons of rejection, given that there actually is no test in the case used in this thread)

If you fall into a group that has a high chance of failing a test anyway, you aren't allowed to donate blood. If you have a high chance of your blood failing, then you have a high chance of wasting resources testing your blood. Resources that could have gone toward someone's blood that had a high chance of passing the tests.

So, in nerd terms: Broadphase Culling :)