Abstract
Many commercial waterless hand sanitizers are available in local markets. These products often state that they kill 99.9 % of microorganisms. The objective of this study was to evaluate the efficacy of a waterless hand sanitizer produced by the Dettol Company that is frequently marketed in Saudi Arabia. The goal was also to isolate hand sanitizer resistant bacteria and study their susceptibility to several of standard antibiotics. The standard washing method was used to disinfect hands using waterless hand sanitizer. Then, the microorganisms were isolated from the hand surfaces. The pure microbial isolates were identified by 16S rRNA gene sequencing. In vitro susceptibility testing was performed using bacitracin, chloramphenicol, cotrimoxazole, gentamicin, neomycin, polymyxin B, tetracycline and penicillin G. The results indicated that 131 microbial isolates were obtained from 90% of hands, whereas no microorganisms were isolated from the remaining 10%. All of the microbial isolates were Bacillus species according to identification by 16S rRNA gene sequencing. The percentage of B. thuringiensis, B. methylotrophicus, B. subtilis and B. cereus isolates were 41.9, 41.9, 12.2 and 3.8 %, respectively. All of the isolates were resistant to bacitracin and penicillin G. The present study indicates that the waterless hand sanitizer produced by Dettol Company does not remove all microbial contamination from hand surfaces.