2017 Volume 32 Issue 2 Pages 85-88
Contamination of reused hand towels by Bacillus cereus spores sometimes causes severe sepsis, and treatment of the towels with disinfectants in the washing process hardly removes the contamination. Evaluation of the degree of the spore contamination of the towels may require the quantification of the contamination although a standard method for it has not been established yet. Therefore, we developed a modified bead extraction method to improve the detection rate of the contamination and then applied the method to measure the contamination with B. cereus of hand towels obtained from a university hospital. Test objects were randomly selected from the washed and dried towels delivered from a laundry company. We cut off 23 pieces from each towel and extracted bacteria from the pieces with the modified method. We found B. cereus contamination of one or more pieces obtained from 7 out of 9 towels. The contamination was rather frequently detected in the pieces from the fringe of the towels that were expected to be clean. Therefore, it is likely that the modified bead extraction method effectively detected B. cereus spore contamination. We also performed scanning electron microscopy to detect spores on the surface of towels that were soaked with B. cereus spore solution. We found B. cereus spores preferentially adhering to niches and wrinkles of towel fibers. Accordingly, we recommend the use of disposable hand towels.
