17 May 2022: Ironside - B

In 2017 the surveillance project reported 178 cases in the UK. The youngest case was aged 12, the oldest 74. At the moment, there are no known cases of anyone living with vCJD. There has not been a case of secondary transmission by surgical instruments, nor from mother to child, nor sexual contact. Transfusion Medication Epidemiological Review reported that there were four probable cases of death from vCJD via transfusion transmission. Prof Ironside prefers to use the terms symptomatic and asymptomatic rather that “pre-clinical” and “sub-clinical”. One person reported on was clearly sufficiently infected to pass on the infection to two of those who died, yet they themselves were asymptomatic. Blood is not a frequent transmission route, but it clearly does happen that way. There have been no changes to the situation since the 2017 report.

The case was cited of a 73-year-old haemophiliac man in the journal “Haemophilia” to which Prof Ironside contributed. Of all the potential routes of transmission related to his life experiences, the authors stated that the most likely infection route was through blood product use. Normally, the infection enters via oral routes (eating contaminated food), then from the gut to the lymph system (appendix, spleen, etc.) and on to the nervous system. The cited case only found the vCJD in his spleen, suggesting it was a recent infection. As expected, vCJD numbers continue to fall year-on-year since there are no known new cases and people with the infection die.

A research report was posted which included some commonly featuring names: Lee, Ludlum, Giangrande, and others including Ironside himself. It looked at vCJD and haemophilia. It involved patient-subjects from London, Oxford, and Edinburgh and used consented brain tissues at autopsy material; although this study was not part of the original purposes for gathering it. Grimly, the incidence of vCJD cases is higher in the North of the country compared to the South. The infectivity level increases dramatically as the patient moves from being asymptomatic to symptomatic. Young people are more susceptible to infection, which might be due to the maturity or not of the immune system. But there may be other factors, including other genes that may influence susceptibility. This is still an area of active research. Today’s evidence became increasingly technical in nature, which might have been expected given the topic. Sometimes it is only the summary which makes the jargon somewhat more penetrable. For example, of all secondary infection cases, every one of these involved blood transmission routes. Referral to Prof Ironside’s unit was not compulsory if a patient was suspected as having possibly been exposed to infection, and neither was the referring agency acting on any advice received compulsory either.

The public health concept of identifying and notifying people who were at risk was seen as significant, for example, to ensure as far as possible that they avoid becoming blood donors. However overall, when it came to having a policy on dealing with people, there was an on-going debate about what was the best thing to do; for example, on whether to notify people, or not. The panel included various specialists, including ethicists. Some of the decisions and recommendations were made after consultation exercises. Over time, policy issues underwent changes, including on notifying, especially if there was a risk of passing the infection on. The work of the Panel took three years. Prof Ironside did acknowledge how long that was, and that it should have been taken forward with more speed. Interim guidance was issued on telling patients about the potential risk they may be living with, but the witness could not say if that guidance was actually sent out. It included guidance on how to deal with patients who wanted to be told their risk status, as well as those who did not want to know.

The guidance also says that patients need to know and understand what it is they may be being told, and then what happens after they are told if they are considered to be at risk. Fundamentally, information should be provided and be up-to-date as far as possible. A meeting which Prof Ironside did not attend but to which he sent his apologies noted how the DH and Lothian Ethics Research body had recommended that certain people should not be told. It highlighted some significant differences in the guidance being issued between Scotland and England at the time. The witness recalls this being a matter of considerable concern. It was only after another associated body had completed its work, that guidance was more aligned across the UK.

One displayed document (from the CJD Incident Panel) spoke of establishing a confidential database of vCJD risk people. There were also discussions concerning blood donations, exclusion of surgical instruments, counselling, but most importantly, about the issue of telling people their risk status. It is obvious that different interests and specialisms were negotiating between them on how to manage the situation, and there may have been professional and inter-specialist trade-offs. An interesting table heading specified the existence of an infectivity measure for intravenous blood where 50% of people who receive that blood will become infectious. So, for a person getting a pooled blood product, each part of that carries a 50% risk, which risk rises exponentially as the number in the pool increases.

(Note, the speed with which the evidence is covered during the live oral hearing sessions, particularly when it is so technical in nature as this session was, is likely to be too great for the writer to always capture and summarise the information accurately as it is happening live. Corrections, clarifications, and comments are welcome.)