The Comparative Study of Effectiveness of Disinfectants by Phenol Co-efficiency against Staphylococcus aureus

Abstract

            Medical instruments  are used for prevention, diagnosis and treatment. It is very important to keep them in disinfection. Using medical instruments in inappropriate sterilization leads to spread of infection in patient to patient, patient to medical staff and to the others. This increase death rate, admission period and costs of treatment. Moreover, the tolerant microorganisms may be spreaded and infected to medical team and community. The aim of this research was to compare the effectiveness of 4 disinfectants (Bioclean ll®,  Mediklen® , Omnicide®  and  Corium95®) against Staphylococcus aureus (S.aureus). The proportion of disinfectant and phenol that did not destroy S. aureus in 5 minutes but totally destroy them in 10 minutes is phenol co-efficiency test (P.C.) Phenol and 4 disinfectants were diluted to 1:20, 1:40, 1:60, 1:80, 1:100 and  1:120 The density of Staphylococcus aureus was prepared by comparison with turbidity of McFarland standard number 0.5. The S. aurous was pipetted into each dilution of phenol and disinfectants and incubated for 5 and 10 minutes. After that, the solutions were spreaded on mannitol salt ager (MSA) and incubated at 37C. After 24 hours, the colonies of S. aureus were counted. The result of this experiment has been shown that P.C. of Bioclean ll®,  Mediklen® , Omnicide®  and  Corium95® were 0.50, 0.33, 0.33 and 0.17 respectively. None of them showed P.C. lower than 0.05 in standard.