Here is a bit more information from Steve Pernal that Eric Mussen included in his newsletter.  
Notice that scorching is not as foolproof as some people believe. 

“ He first looked at  possible ways to decontaminate woodenware from hives  containing dead 
larvae,  scale, and contaminated food  stores. 

1. Scorching and  Virkon S ® were about 84%  effective.  
2. Powered water  was 81% effective.  
3. Scrubbing was 77% effective.  
4.  Steam and lye were nearly  100% effective, as is  irradiation.” 

Regards,
Dick Allen

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