Effect of Certain Disinfectants and Antibiotics on the Biofilm Formed by Staphylococcus Aureus Isolated from Medical Devices at the University Hospital Center of Sidi Bel Abbes (Algeria)

Staphylococcus aureus is one of the species that are most frequently isolated from medical devices. The ability to produce a biofilm is an important step in the pathogenesis of these staphylococci; biofilm formation is strongly dependent on the environmental conditions and also on the antibiotics and disinfectants used in the treatment of infections. In this study, 28 staphylococcus aureus isolated from medical devices at the University Hospital Center of Sidi Bel Abbes (in Northwestern Algeria) were analyzed to detect the formation of biofilm by culture on Red Congo Agar (RCA). The Tube Method (TM) and tissue Culture Plate (TCP) techniques were also used to investigate the effect of penicillin, ethanol and Betadine on the preformed biofilm. It has been found that 19 strains produced a bacterial slime on the Congo red medium, 7 strains produced a biofilm by the tube method, 2 of which are highly productive. In addition, 9 strains produced a biofilm on polystyrene micro-plates; this number was higher in the presence of penicillin and ethanol with 19 and 11 biofilm producing strains, respectively. On the other hand, no biofilm was formed in the presence of Betadine. It is important to examine the response of biofilms following an imposed external constraint such as disinfectants and antibiotics in order to develop new strategies to combat bacterial biofilms but also to better control their formation.