Evaluation of efficacy of the current disinfectants on staphylococcus epidermidis and pseudomonas aeroginosa isolated from hospitals of Hamadan in 2006

Background: Choosing the effective disinfectants and using the standard methods of sterilization in
hospitals, can be useful in decreasing nosocomial infections. The aims of this study were the evaluation of
efficacy of disinfectants being used in surgical rooms, ICU, CCU, burn wards and delivery rooms of
Hamedan hospitals and also determination of bacterial contamination.
Methods and Materials: In this study 400 samples were collected from different parts of operation rooms,
ICU, CCU and delivery rooms of four hospitals (Mobasher Kashani, Imam Khomainy, Ekbatan and
Fatemieh) in 2006. The samples were cultured on blood agar, then the microbial agents were identified by
differential and biochemical tests. Disinfectants that were used were as follow: Cidex (Glutaraldeyde),
Sodium hypochlorite, Kereoeline 2.5%, Hygiene1%, Betadine, Alcohol 70%, Savlone 3.2%, Chlorohexidine
1%. The efficacy of disinfectants was evaluated on 60 Staphylococcus epidermidis and 60 Pseudomonas
aeroginosa through disk diffusion method. Data were gathered through a questionnaire and analysed using
T-test and SPSS software.
Results: Contamination tests in the four hospital were positive in 44.5% of cultures (178 cultures). The
highest frequency of contamination was in Mobasher hospital with 38.2% and the less frequency was in
Fatemieh hospital with 13.5%. From 400 samples, 52.2% of isolates were gram-positive bacteria and 47.7%
were gram-negative bacteria. The most important bacteria isolated were as follow: E.coli, Staphylococcus
epidemidis, Micrococci, Bacillus subtili and Pseudomonas aeroginosa. The most effective disinfectants on 60
Staphylococcus epidemidis were as follow: Cidex, Sodium Hypochlorite and Kereoeline and the least
effective disinfectants and antiseptics was Alcohol 70%. The most effective disinfectants on 60 Pseudomonas
aeroginosa were as follow: Cidex and Kereoeline and the least effective disinfectants and antiseptics were
Alcohol 70% and Savlone.
Conclusion: results showed that kereoline and cidex were among the most effective disinfectants, and
there is not a significant difference between their effects on staphylococcus epidermidis (P=0.469) and on
pseudomonas aeroginosa (P=0.053). The efficacy of other disinfectants on two mentioned bacteria were
different and significant differences were found.