Technology : A new blood feud?
1
53 53 In August 2001 scientists at the University of California announced they had found a possible cure for variant Creutzfeldt-Jakob disease (vCJD). This wonderful news once again calls into question the wisdom of some of the ‘precautionary’ measures taken with regard to vCJD. CJD is a horrible disease, and one can only feel pity for sufferers and their families. But CJD is also exceptionally rare, affecting fewer than two people in a million each year.The majority of cases are sporadic, caused by normal ageing of the body’s repair mechanisms.A very small number are caused by an inherited abnormality. Some have also been traced to medical procedures, including corneal transplants and injections of human growth hormone. Just over 100 cases of vCJD have been identified since 1994. In spite of millions of dollars of research and thousands of hours of government inquiries, the cause of vCJD remains mysterious, although there is some evidence of a link to BSE. Both BSE and vCJD are characterised by the presence of large numbers of abnormal, or ‘misfolded’ prions – an unusual self-replicating form of protein. Normal prions are harmless.When they come into contact with misfolded prions, however, they turn into monsters capable of wreaking havoc on the brain’s delicate structure, turning it into a spongy mass. Whatever the cause of vCJD,it now seems unlikely that more than a few hundred people will succumb. First, the observed incidence of vCJD is not increasing rapidly enough to justify more catastrophic predictions. Second, because it seems likely that a cure will be found quite soon. The best hope of a cure so far has come from the Berkeley lab of Professor Stanley Pruisner, the scientist who won the Nobel Prize for his discovery of prions. His team has been searching for molecules that inhibit the conversion of normal prions into misfolded prions. Fortunately, two of the most effective molecules, chlorpromazine and quinacrine, have already been used extensively by humans for the treatment of schizophrenia and malaria, so their side effects are relatively well understood. Meanwhile, numerous governments and other organisations have imposed restrictions on the use of blood and blood products on the grounds that they might cause vCJD. In 1998, the UK banned the use of blood donated by Brits for the manufacture of blood products. Britain now imports blood factors from the US. Several countries, including France and Spain, have banned blood donations from people who have spent long periods of time in the UK. More recently, the American Red Cross – which collects 45% of blood donations in the United States – decided to ban blood donations from anyone who has spent more than three months in Britain, or six months in Europe, since 1980. The justification for these restrictions is that animal experiments have shown that vCJD might be transmitted through blood. However, the risks of such transmission are essentially theoretical.There are very few prions in blood to begin with. More importantly, if vCJD were transmitted by blood transfusions or through blood products, people in Britain and other European countries would be at a much higher risk of exposure. Over the past ten years, 30 to 40 million blood transfusions have been conducted in the UK – including several from people who subsequently died from vCJD.And yet not a single case of vCJD has been detected among recipients of blood or blood products. The theoretical risk of infection with vCJD must be weighed against the very real risks of reducing the availability of blood and blood products.New York City,which receives approximately 25% of its blood from Europe, is already postponing 8% of all operations because of the shortage of blood. If more restrictions are imposed on the use of blood from people in Europe, thousands of people will have to wait longer for elective surgery,with resultant complications and discomfort. In some cases, even patients who require blood for emergency procedures may have their operations delayed.Some will probably die. People who rely on blood factors (in both the US and Europe) – such as those with immunodeficiency or haemophilia – will either pay more for their medication, or will suffer. Some will die. In an environment of heightened fear over the risk of vCJD, governments seek the option that minimises blame.To keep supplies ‘absolutely’ safe, governments in countries without vCJD or BSE might soon feel obliged to ban imports of blood and blood products from other countries. Eventually, no doubt, the government would come under pressure to ban exports of blood, and blood products, too – after all, we cannot have poor people in the US dying while American blood goes to treat wealthy foreigners. The consequence for people living in Britain and other countries where outbreaks of BSE and vCJD have occurred could be devastating.At the very least, it would force the UK government to overturn its ban on the use of British blood for the manufacture of blood products. But even so, the reduction in flexibility of supply of blood and blood products would be deadly bringing new meaning to the term ‘blood feud.’ Technology A new blood feud? Julian Morris IEA Research Fellow and Director of International Policy Network (www.policynetwork.net) ECONOMIC AFFAIRS December 2001 © Institute of Economic Affairs 2001 Published by Blackwell Publishers Columns
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Transcript of Technology : A new blood feud?
5353
In August 2001 scientists at the University ofCalifornia announced they had found a possible cure for variant Creutzfeldt-Jakob disease (vCJD).This wonderful news once again calls into questionthe wisdom of some of the ‘precautionary’ measurestaken with regard to vCJD.
CJD is a horrible disease, and one can only feel pity for sufferers and their families. But CJD is alsoexceptionally rare, affecting fewer than two people in a million each year.The majority of cases aresporadic, caused by normal ageing of the body’s repairmechanisms.A very small number are caused by aninherited abnormality. Some have also been traced tomedical procedures, including corneal transplants andinjections of human growth hormone.
Just over 100 cases of vCJD have been identifiedsince 1994. In spite of millions of dollars of researchand thousands of hours of government inquiries, thecause of vCJD remains mysterious, although there issome evidence of a link to BSE. Both BSE and vCJDare characterised by the presence of large numbers of abnormal, or ‘misfolded’ prions – an unusual self-replicating form of protein. Normal prions areharmless.When they come into contact withmisfolded prions, however, they turn into monsterscapable of wreaking havoc on the brain’s delicatestructure, turning it into a spongy mass.
Whatever the cause of vCJD, it now seems unlikelythat more than a few hundred people will succumb.First, the observed incidence of vCJD is notincreasing rapidly enough to justify more catastrophicpredictions. Second, because it seems likely that a curewill be found quite soon.
The best hope of a cure so far has come from theBerkeley lab of Professor Stanley Pruisner, thescientist who won the Nobel Prize for his discoveryof prions. His team has been searching for moleculesthat inhibit the conversion of normal prions intomisfolded prions. Fortunately, two of the mosteffective molecules, chlorpromazine and quinacrine,have already been used extensively by humans for the treatment of schizophrenia and malaria, so theirside effects are relatively well understood.
Meanwhile, numerous governments and otherorganisations have imposed restrictions on the use of blood and blood products on the grounds thatthey might cause vCJD. In 1998, the UK banned theuse of blood donated by Brits for the manufacture ofblood products. Britain now imports blood factorsfrom the US. Several countries, including France and Spain, have banned blood donations from peoplewho have spent long periods of time in the UK.
More recently, the American Red Cross – whichcollects 45% of blood donations in the United States– decided to ban blood donations from anyone whohas spent more than three months in Britain, or sixmonths in Europe, since 1980.
The justification for these restrictions is that animalexperiments have shown that vCJD might betransmitted through blood. However, the risks of suchtransmission are essentially theoretical.There are veryfew prions in blood to begin with. More importantly,if vCJD were transmitted by blood transfusions orthrough blood products, people in Britain and otherEuropean countries would be at a much higher riskof exposure. Over the past ten years, 30 to 40 millionblood transfusions have been conducted in the UK –including several from people who subsequently diedfrom vCJD.And yet not a single case of vCJD has beendetected among recipients of blood or blood products.
The theoretical risk of infection with vCJD mustbe weighed against the very real risks of reducing theavailability of blood and blood products. New YorkCity, which receives approximately 25% of its blood from Europe, is already postponing 8% of all operations because of the shortage of blood.If more restrictions are imposed on the use of bloodfrom people in Europe, thousands of people will haveto wait longer for elective surgery, with resultantcomplications and discomfort. In some cases, evenpatients who require blood for emergency proceduresmay have their operations delayed. Some will probablydie. People who rely on blood factors (in both the USand Europe) – such as those with immunodeficiencyor haemophilia – will either pay more for theirmedication, or will suffer. Some will die.
In an environment of heightened fear over the riskof vCJD, governments seek the option that minimisesblame.To keep supplies ‘absolutely’ safe, governmentsin countries without vCJD or BSE might soon feelobliged to ban imports of blood and blood productsfrom other countries. Eventually, no doubt, thegovernment would come under pressure to banexports of blood, and blood products, too – after all,we cannot have poor people in the US dying whileAmerican blood goes to treat wealthy foreigners.The consequence for people living in Britain andother countries where outbreaks of BSE and vCJDhave occurred could be devastating.At the very least,it would force the UK government to overturn itsban on the use of British blood for the manufactureof blood products. But even so, the reduction inflexibility of supply of blood and blood productswould be deadly bringing new meaning to the term‘blood feud.’
Technology
A new bloodfeud?
Julian Morris
IEA Research Fellow and Director
of International Policy Network
(www.policynetwork.net)
ECONOMIC AFFAIRS
December 2001
© Institute of Economic Affairs 2001
Published by Blackwell Publishers
Colu
mns
