Biofilm inhibitory and eradicating activity of wound care products againstStaphylococcus aureusandStaphylococcus epidermidisbiofilms in anin vitrochronic wound model

Abstract

Although several factors contribute to wound healing, bacterial infections and the presence of biofilm can significantly affect healing. Despite that this clearly indicates that therapies should address biofilm in wounds, only few wound care products have been evaluated for their antibiofilm effect. For this reason, we developed a rapid quantification approach to investigate the efficacy of wound care products on wounds infected with Staphylococcus spp. An in vitro chronic wound infection model was used in which a fluorescent Staph.aureus strain was used to allow the rapid quantification of the bacterial burden after treatment. A good correlation was observed between the fluorescence signal and the bacterial counts. When evaluated in this model, several commonly used wound dressings and wound care products inhibited biofilm formation resulting in a decrease between one and seven log CFU per biofilm compared with biofilm formed in the absence of products. In contrast, most dressings only moderately affected mature biofilms. Our model allowed the rapid quantification of the bacterial burden after treatment. However, the efficacy of treatment varied between the different types of dressings and/or wound care products. Our model can be used to compare the efficacy of wound care products to inhibit biofilm formation and/or eradicate mature biofilms. In addition, the results indicate that treatment of infected wounds should be started as soon as possible and that novel products with more potent antibiofilm activity are needed.