vCJD
The IBTS has decided to remove the permanent deferral regarding vCJD associated with UK residency and certain surgical procedures. This means that from 7th October 2019 donors who have been deferred by the IBTS for this reason or people who have not attended a clinic for this reason may now be eligible to give blood provided that they meet our other medical guidelines.
Q. What has changed?
In 2019 the IBTS undertook a comprehensive review of the vCJD risk associated with blood transfusion. On examination of the available evidence, it was decided to remove the deferral for people who had spent 12 months or more in the UK* between the years 1980 and 1996 along with certain surgical / dental procedures. These deferrals were introduced as a precaution. The IBTS was concerned that there would be a significant risk to the blood supply from donors who had been exposed to vCJD. Whilst there have been 4 probable cases of transfusion transmission of vCJD, these occurred before the blood services started to remove white cells from donated blood and none of these cases were in Ireland. There have been no reported cases of vCJD in people born after 1989.
Q. Are there people who still can’t donate?
Yes, if you have had brain or spinal cord surgery in the UK* since the 01st January 1980 you are not eligible to be a donor. This is because there is a high infectivity risk associated with these tissues. You may not donate if you had a blood transfusion in the UK at any time or if you had a blood transfusion in the Republic of Ireland after 1980.
Q. What is variant Creutzfeldt - Jakob disease (vCJD)?
vCJD is the human form of Bovine Spongiform Encephalopathy (BSE) otherwise known as “Mad Cow Disease”. It was first reported in the United Kingdom* (UK) in 1996. It is acquired by eating bovine meat containing central nervous system tissue from infected cattle that carry an abnormal prion protein. This is accepted as being the same agent that causes BSE. There are other forms of CJD some of which are inherited and these are not related to the food chain.
Q. How many cases of vCJD have there been in the UK*?
To date there have been 178 cases of vCJD in the UK* the great majority of these were probably caused by eating contaminated meat products. There were 4 cases in Ireland. There have been no cases reported in Ireland since 2006 and furthermore there have been no reported cases of vCJD in people born after 1989.
Q. What are the risks associated with contracting vCJD?
The main risk associated with contracting vCJD was dietary exposure to meat or meat products particularly those products containing central nervous system tissue infected with BSE. This could have occurred through residing in the UK in the years 1980 to 1996, or from consuming infected meat or meat products in Ireland, either imported from the UK or from Irish sources, before all control measures were in place. A secondary risk was associated with certain operations carried out in the UK (including laser eye surgery and root canal treatment). However, there have been no known cases of vCJD transmission via surgical instruments to date.
Q Why were donors that lived in the UK* unable to donate?
At the peak of the epidemic in the UK*, it was noted that some of the patients presenting with the disease had been blood donors. On further investigation it was found that 3 recipients of blood had succumbed to the disease thus establishing the possibility that vCJD could be transmitted by blood transfusion. A fourth recipient who had died from an unrelated condition had abnormal prion protein at autopsy. In 1999 the IBTS decided to remove white cells from donated blood and this has proved an effective method of preventing transmission of the disease. No cases of transfusion transmitted vCJD have occurred to date with blood from which white cells were removed prior to transfusion.
Q. Are people who lived in the UK* between 1980 and 1996 at risk of contracting vCJD?
The risk of contracting vCJD through travelling and living in the UK* in this period is considered to be low. It should be noted that in the UK* where tens of millions of people were potentially exposed to vCJD through eating infected food, there have only been 178 cases of the disease to date.
Q. What was significant about residence in the UK* in the period 1980 to 1996?
This period covers the epidemic of BSE in cattle in the UK* that occurred in the years 1980 to 1996. The first cases of BSE in cattle in the UK* were reported in 1986. Scientists believe the incubation period for the disease in cattle is about five years, so BSE most likely first appeared in cattle around 1980. It is thought that BSE occurred in cattle that were fed processed meat and bone meal from other animals. The UK* introduced control measures to reduce the risk of humans being exposed to infection. These measures have been fully implemented in the UK* since 1996.
Q. Will there be more cases of vCJD in the UK*?
The last reported case of vCJD in the UK* was in 2016. Some cases of vCJD may still occur, but risk assessment predicts a much lower number than was originally predicted. There have been no reported cases of vCJD in people born after 1989. There are now much tighter regulations in the agri-food sector that have been put in place since the outbreak of vCJD. These measures were put in place to prevent another outbreak of vCJD.
Q. I have a family member who had vCJD, can I donate?
Yes. A family history of vCJD is not a reason for deferral.
Q. Is there a test for vCJD?
There is no test currently available for large scale screening of blood donors for vCJD.
*The UK includes Northern Ireland, England, Scotland, Wales, the Channel Islands and the Isle of Man.
For more information
For more information watch the recent interview about the lifting of the deferral by our Medical & Scientific Director, Dr Stephen Field.
