nvCJD is believed to originate from eating beef where the animal had BSE (Bovine spongiform encephalopathies) or 'Mad Cow Disease'. By 2006 153 deaths had been attributed to eating BSE infected beef or from medical procedures where the infectious agents were passed on.
BSE was first identified in cattle in the UK around 1986. Once it was established that the probable cause of the disease was that cattle had been fed animal protine to increase milk yields, I and my family stopped eating beef from the UK. I realised that if it could survive the temperature involved in the processing and pass from sheep to cattle then there was a good chance that it would pass to humans also.
It was several years later (1990) that the 'BSE scare' reached a peak and the UK health minister publicly ate a beefburger to calm fears. That didn't reassure me though. Next came a daft idea that 'they' would ban the sale of beef from cattle more than 30 months old and therefore ensure public safety. Now it usually takes longer than that for symptoms of BSE to appear in cattle and this idea means that it was then impossible to detect if the meat was infected or not! A much more sensible idea would have been to ban the sale of meat younger than 30 months and therefore give the disease a chance to develop to the point where it could be detected.
The 30 month rule ended in November 2005 and was replaced by the compulsory testing of slaughtered animals for BSE.
The use of animal protein in cattle food was banned in July 1988. It was expected that the appearance of new cases would gradually stop. When cows born after the 1988 ban started to develop symptoms, it became apparent that BSE could be passed from mother to calf. The UK government body which deals with BSE, the Department for Environment, Food and Rural Affairs (DEFRA) introduced in May 2006 an 'offspring cull' where the calves of any cow determined to be infected with BSE were to be slaughtered. A great idea, but the regulation does not go far enough. It applies only to calves born in the previous two years, and, as DEFRA itself declares, on average it takes five years for BSE symptoms to appear. It has not been established if BSE can be passed on in this incubation period. A safer, (but much more expensive), policy would have been for all descendants of a BSE infected cow to be slaughtered.
So what exactly is the situation now?
The UK has by far had the greatest number of cases of BSE and it is certain that some infected animals entered the UK food chain. Since nvCJD may remain dormant for very long periods - 20 years and more, so far we may only have seen nvCJD in those people particularly susceptible to it. There may be a huge number of cases about to appear in the next few years. See the chart at the end of this post.
Cases of BSE in the UK are now much better controlled. If the steps are effective then BSE will disappear in the UK. I suspect there will still be some since it's possible that the two year offspring cull is not enough to eradicate it. I personally still won't eat British beef unless I know it's from a purebred 'non-dairy' beef herd such as Aberdeen Angus and preferably one which is 'grass fed'.
The table below, based on latest results for 2005, shows the likelihood you have of finding a BSE infected animal. All countries where a BSE case has been confirmed are shown.
|Country||Current odds 1 in:|
What's more worrying however is the graph showing potential cases of nvCJD which could exist:. People in the UK don't seem to be aware that some countries (e.g. Belgium) will not accept blood donors who lived in the UK during the 1990s.
For more information on BSE try http://www.food.gov.uk/bse/ and http://www.bseinquiry.gov.uk/
For information on new variant Creutzfeldt-Jacob Disease try http://www.cjdfoundation.org/ or http://www.stanford.edu/~siegelr/ajai.html