Abstract
The inactivation of Tyzzer's organism (Bacillus piliformis) spore isolated from rats by heat and various chemical disinfectants was studied. The spores were from B. pili-formis-infected rat liver tissues. The spore suspension (104 50% of rat liver lesion producing dose with prednisolone treatment/ml) was treated with heart or disinfectants. Inactivation of the spores was examined in experimentally infected rats. Rats were inoculated perorally with a treated spore suspension and injected subcutaneously with prednisolone. On the sixth day after inoculation, rats were examined grossly for liver lesions. Spores were inactivated at 80°C for 15 min but not at 60°C for 30 min. Spores were inactivated by 0.4 % peracetic acid, 0.015 % sodium hypochrolite, 1 % iodophol, 5 % phenol. AlcideTM and 0.37 % formaldehyde solution, but not by 0.037% formaldehyde solution, 70 % ethanol, 0.3 % benzethonium chroride solution, 3 % cresol and soap solution, or 4 % chlorhexidine digluconate. These findings suggest that B. piliformis spores are relatively sensitive to heat and certain chemical disinfectants.
