Evaluation of antibacterial activity of hand sanitizers – an in vitro study

Abstract

Hand hygiene, particularly hand sanitizing, is essential in reducing infectious disease transmission. The recent outbreak of Ebola in Nigeria both increased public awareness of the practice of hand sanitizing and resulted in the introduction of new products to the Nigerian market. This study set out to explore the actual antibacterial activity of these products against key clinical isolates using both dilution and diffusion susceptibility tests methods. Results showed higher inhibitory activity of the products to Klebsiella pneumoniae and Staphylococcus aureus than Escherichia coli and Pseudomonas aeruginosa. Overall the only local product tested had the least inhibitory activity. In general however, the sanitizers showed good activities, with inhibition of bacteria noted at concentrations as low as 25%. Products tested in this study showed higher zones of inhibition than previously reported, indicating their overall effectiveness. The variations in diffusion and dilution results highlight the effect of texture of the sanitizing product on testing methods and point at a need to properly assess if this could perhaps have any effect in real time on inhibitory activities. The hand sanitizing products tested in this study are suitable in disease prevention. However, regulatory bodies may need to focus on product texture until the effect of this on activity is determined.

Keywords: Sanitizer, Nigeria, dilution, MIC, bacteriocidal