Quote from http://news.scotsman.com/topics.cfm?tid=671&id=1118012006
No case of vCJD has so far been linked to surgical instruments. But Dr Garske said theoretical models found it was possible that hundreds of deaths could occur between 2006 and 2021 as a result of infection with vCJD via surgery. It was also possible that there would be no cases, due to uncertainties about the risks of transmission on reused instruments and the lack of data on how often they are reused.
I read this as meaning that they are not certain, because of the lack of data, and that MAY be why they can not prove cause and effect. They are concerned about the theoretical models, at least, that is what I think they are saying.
They are certainly proceeding as if they are concerned.
And then, this seems like a lot of people who had surgery, happened to develop this disease. Is really not higher than the rest of the population?
Of 161 people diagnosed with vCJD by the end of 2005, 130 had had surgery in the years preceding the start of symptoms. But there was no evidence to suggest this was higher than the rest of the population, the report said.