The bactericidal effect of microwaves on Mycobacterium bovis dried on scalpel blades.

The action of microwaves on stainless steel scalpel blades contaminated with Mycobacterium bovis was investigated. The complete destruction of M. bovis was obtained with 4 min of microwave exposure. When the preparations were subjected to scanning electron microscopy, the bacteria had undergone a progressive series of alterations consisting, initially, of the formation of deep pits in the bacterial body and eventually the complete disintegration of the microorganisms. Such phenomena are less evident when this mycobacterium is exposed to other sterilization methods such as dry heat or autoclaving.