I gave blood every two months for more than a decade. Not long ago, on very short notice, the Red Cross told me that I couldn’t donate any more, as I’d spent more than a cumulative six months of my life in the UK and might have been exposed to Mad Cow Disease/BSE/Creutzfeldt-Jakob through meat I’d eaten while I was there. “Is there a test I can take to see if I’ve been exposed?” I asked. No, I was told. And don’t let the door hit you on the way out (or so it seemed).
That sucked, but what comes next? Is there any prospect for a test to let me, and many others who’d happily keep donating blood, know if we have the disease?
Yeah, 20 years after I was in Germany, and more than 10 years donating they decided that I was a risk too. I just checked, cuz this is my birthday is next week and I always liked to donate on it, and they nope nothing on the horizon. My guess is that there’s not enough market to justify the expense.
Larry
I tell you, it’s aggravating to hear all those radio PSAs about blood emergencies, begging people to get off their asses and give blood, but they won’t take mine because I might have MCD from the late 1980s. Then again, I might not. Sheesh.
The cause of variant Creutzfeldt-Jakob Disease (vCJD), the manifestation in humans of Bovine Spongiform Encephalopathy (BSE), is a prion (which is short for proteinacious infectious particle…yeah, it doesn’t really make sense, deal with it; the discover, Nobel laureate Stanley Pruisner clearly wanted to make an conceptual analogue to a viron). This is a normal protein found in the brain but folded in an abnormal way. Like the fictional Ice-9 in Cat’s Cradle, prions seem to beget other proteins to fold in the same way, resulting in dysfunction and the formation of spongiform encephalophy–in plain English, your brain turns into Lorraine Swiss cheese, which as you might imagine is detrimental to the normal functioning of cereberal processes.
Since the prion doesn’t really interact and stimulate an immune response or reactivity the way viruses or bacteria do, there’s no noninvasive direct test like a blood or lymphatic fluid sample; you basically have to take sample of infected tissue and examine it under a microscope as Gorsnak indicates. Since prion transmission requires contact with brain tissue it’s not readily transmissible between people (unless you’re into the whole cannibalism scene) but it’s possible–though highly unlikely–that particles could enter the blood stream and be transmitted to a donor, as the proteins are certainly small enough to penetrate through the blood brain barrier in the way that most viruses and bacteria can’t. It is also believed that infection by as much as a single particle is sufficient to instigate the syndrome, as again the immune system can do nothing to stop it.
Since their discovery TSEs are becoming increasingly prevelent in diagnostic pathology. The likelyhood that BSE exists in the United States is very high, though the actual incidence (as it is in Europe) is very low owning to low occurance of transmissability (though this clearly varies–scrapie and chronic wasting disease are somehow transmitted in herds of sheep and deer/elk respectively, and these are strict herbivores, so presumably other mechanisms of transmission are at work. (Cows are thought to normally get it by eating feed rendered from the remains of infected cattle, a practice that has been discontinued in the developed world.) TSEs can also occur spontaneously, but at very low incidence. Again, diagnosis is via displayed symptoms as the syndrome runs its inevitable course and confirmed by post-mortem forensic examination. There is no effective treatment and no current avenue of research that gives promise of a cure, hence the prohibition against blood donation for those who are percieved as being likely to have been exposed.
An effective diagnostic isn’t just a matter of cost, but one of technology. Until we have the capability of using nanobiological probes that can enter the brain and identify the malformed proteins (and despite what you might read in Popular Science we are decades away from that) there is really no hope of a reliable test.
Since vCJD has such a long latency before manifesting and the only way to evaluate the pathology pre-mortem is via displayed symptoms it’s difficult to quantitatively characterize the likelyhood of transmission, or indeed, the incidence of the syndrome in the general blood-donating population. Public policy in this regard may be overcautious but given the untreatable nature and uncertainty regarding transmissability of the disease a risk-adverse approach is arguably warranted.
If I can piggyback onto this question… I’m in a similar situation, but my restriction is based upon cumulative time in France, not England. Either way, I don’t donate (although I think I might have technically been able to squeeze by the Canadian Blood Services limit of 3 months, I definitely cannot pass Héma-Québec’s 6 months cumulative!) I have occasionally given money, though.
Organs are another matter… for most (all?) organ recepients, they are pretty much facing an early death without a transplant, correct? I have asked several CBS and Héma-Québec volunteers, a CLSC nurse, and a doctor, and I think I may have asked on these boards, but are the same restrictions in place for organ donations? I haven’t been able to get an answer, and I keep filling out my organ donation card, because I figure the theoretical risk of vCJD is something someone with heart/lung/liver/kideny etc failure is willing to chance. Does anyone know where doctors or regulatory bodies stand on this? Specifically, I’d like to know for Québec, Canada, but any other jurisdiction would at least give me some idea of what the policy might be!
So, a definite risk, with a proven history. Three cases doesn’t sound that high, but compared to the total numbers, and the numbers out of recorded exposure to blood products, it looks to me to be a reasonable precaution.
In the article Stranger cited it showed a latency period of less than a decade. I was stationed in Germany 20 years ago and am now excluded from donating. If I had contract CJD/BSE, wouldn’t it have show up by now? Shouldn’t I be stumbling around, drooling and being forgetful? I mean, more than I usually do? If you have passed the latency period, why can’t they let me donate again?
However, not knowing if I do have it is a great excuse for getting away with stuff. “Sorry I forgot our anniversary, honey. It’s the Mad Cow Disease.” “can’t come to work today, boss. The Mad Cow is really bad today and I can’t drive.”
