February 17, 2009

experts comment on haemophiliac vCJD

Concern was raised over the safety of haemophilia patients after the death of a man who had been treated with a blood clotting agent infected with variant Creutzfeldt-Jakob disease (vCJD), the human form of BSE, although this was not the cause of his death.

Prof Chris Higgins, Vice-Chancellor of Durham University and Chair of the Spongiform Encephalopathy Advisory Committee (SEAC), said:

“This is not a new outbreak of vCJD and has no immediate implications for public health or public health policy. Indeed, this finding is not unexpected for a haemophiliac who was at risk of exposure to infection in the 1980s and 1990s through blood products received before strict transfusion rules were introduced. Appropriate precautions have been in place since then to minimise the risk of any new infections.

“This patient died from causes unrelated to vCJD and displayed no clinical symptoms of vCJD. There are still some scientific questions to be addressed and these will be considered by SEAC as soon as data emerge.”

Prof David Allsop, Professor of Neuroscience at Lancaster University, said:

“This haemophilia patient was treated some time ago with clotting factors from a human donor who subsequently (within six months of donation) went on to develop symptoms of the human ‘new variant’ form of CJD. At post-mortem analysis, the patient was found to be ‘incubating’ the abnormal prion protein that causes this disease. Given the extreme rarity of human CJD, this certainly looks like more than a co-incidence, and it is likely that the haemophilia patient did acquire the latent infection from blood clotting products.

“There is, however, no need for widespread concern amongst haemophilia sufferers because the risks of transmission in this way have now been virtually eliminated because of precautions introduced (in 1999) involving the sourcing of human blood products from outside the UK, and the use of synthetic clotting factors. The only real cause for concern is for other haemophilia patients who received clotting factors from the same infected human donor, at around the same period of time; and they can presumably be traced and given specialist advice.”