Comparative Studies of the Efficacy of Some Disinfectants on Human Pathogens

The anti microbial activities of three commonly used disinfectants Septol, Dettol and Z-germicides against Escherichia coli, Staphylococcus aureus and Candida albicans were investigated. Their efficacies were determined using the agar diffusion method at different concentrations of the test disinfectants and their potency was tested against a standard (phenol) by using phenol coefficient tests. The use of Septol on E.coli and S.aureus showed weak bactericidal efficacy with a zone of inhibition of 30mm and 29mm at 100% concentrations as compared to the others, even in their use in dilutions, although it possesses a high efficacy against C.albicans with a zone of inhibition of 75mm. Dettol and Zgermicides had equal inhibitory effects of 45mm on E.coli and S.aureus at 100% concentrations but Dettol was more effective, as compared to Z-germicides, although S.aureus was observed to be the most susceptible to Z-germicides when used in higher concentrations. It was observed that as the concentration reduces the susceptibility rates of the test organisms increases. The potency of the disinfectants against a standard disinfectant (phenol) showed that they were all more effective than phenol with Dettol being the most potent disinfectant as compared to both Z-germicide and Septol. To ensure disinfectants efficacy, tests should be carried out on new disinfectant products and also further studies should be carried out about disinfectants