Determination of Resistance of Enterococcal Isolates to Common Chemicals used for Disinfection in Homes and Hospitals

Abstract

Aim: To determine the resistance Enterococcal isolates to common chemical agents used for disinfection in homes and hospitals. Place and Duration of the Study: Enugu State University of Technology (ESUT) Teaching Hospital, Parklane and University of Nigeria Teaching Hospital (UNTH), Ituku Ozalla, Enugu State, Nigeria, between July 2012 and June 2014. Methods: The study analysed antimicrobial products such as Dettol, Hibitane and Jik. Identification of the organism was based on standard procedure and biochemical test. Results: All the three representative isolates, E. facium, E. faecalis and E. avium showed luxuriant growth with optical density (OD) range of 0.31 to 0.35 at Sodium Chloride concentration of 0.5%. The growth (OD) reduced as the salt concentration increased. E. faecium, E. faecalis and E. avium showed no growth at the concentration of 10%. Dettol had MIC of 0.385 mg/ml and MBC of 0.75 mg/ml on E. faecium; MIC of 0.75 mg/ml and MBC of 1.5 mg/ml on E. faecalis; MIC of 0.193 mg/ml and MBC of 0.385 mg/ml on E. avium. Hibitane had MIC of 0.781 mg/ml and MBC of 1.568 mg/ml on E. faecium; MIC of 1.563 mg/ml and MBC of 3.125 mg/ml on E. faecalis; MIC of 0.781 mg/ml and MBC of 1.563 mg/ml on E. avium. Jik had an MIC of 0.547 mg/ml and MBC of 1.094 mg/ml on E. faecium; MIC of 1.094 mg/ml and MBC of 2.188 mg/ml on E. faecalis; MIC of 0.547 mg/ml and MBC of 1.094 mg/ml on E. avium. Conclusion: The growth of the isolates reduced as the salt concentration increased. The MICs and MBCs values from this study showed that these disinfectants are effective against Enterococci sp. in the following order; Dettol (Chloroxylenol), Jik (sodium hypochlorite) and Habitane (Chlorhexidine gluconate). The study therefore showed that concentration of various disinfectants/antiseptics used in hospital settings, medical laboratory section and at home should be of paramount interest for safe elimination of Enterococci.