Hi There

My name is Marko and I'm looking for information (Operating procedure) in dealing with the sterilization of PRION contaminated instruments. We are manufacturers of steam sterilizers and a client approched me and asked me about the correct spec to sterilize prions using a steam sterilizer. They recently had a case where a patient was indentified with Creutzfeldt Jacob disease and were very uncertain on how to handle the situasion. Please help!! Information regarding exposure times, correct temperatures etc. will be very helpful.

Best regards.
Marko Marais

Marko

You will find differing responses to the methods to combat CJD contamination. In the UK - where the problem started - we originally used a long exposure period equivalent to six cycles at 134-137C. This meant an 18 minute exposure period. This was based on old research which, when repeated, suggested that the 18 minute cycle was not as effective as first thought. We now utilise the washer-disinfector process as the main ammunition against CJD where, if the washer-disinfector can be validated to remove all protein, a conventional sterilization process is acceptable as their is no protein (hence no CJD) to deactivate. This procedure, however, relies on the proper specification, construction, validation and routine testing of the washer-disinfector with particular reference to routine protein residual tests. Other countries rely on the overlong hold period at 134-137C - sometimes in excess of 18 minutes - to deactivate prions and I believe that there is, as yet, no evidence to demonstrate that any approach is/is not working.

Any answer to your question should be based on evidence to demonstrate that whatever solution is chosen the prion is deactivated or removed. I suspect that in a continually-changing situation we may well be using different solutions as more evidence, research and information enables us to understand the problem better.

Sorry for not answering the question!

Peter Hooper