In vitro bactericidal efficacy of a new sun- and heat burn gel

SummaryWe assessed the in vitro bactericidal efficacy of a new sunburn gel (Rescuderm™; RESC) against planktonic and sessile Pseudomonas aeruginosa (PSEUD) and Staphylococcus epidermidis (STAPH). While PSEUD levels were 4 log10 lower than those of STAPH within 24 h of adding RESC to contaminated nutrient broths, all bacterial counts were comparable by 48 h. PSEUD and STAPH levels were then measured after applying either a single or three consecutive aliquots of RESC to polyurethane sponges. Gel was removed after 5 or 20 min, or left on for 72 h. Bacterial counts in placebo-treated sponges had plateaued by 24 h to values above 9 log10 CFU/mL. In contrast, six out of seven of the RESC application modalities reduced bacterial levels below 4 log10 CFU/mL for 72 h. RESC remained effective against STAPH despite up to a 24 h treatment delay, irrespective of the number of applications. Repeated RESC applications were required to maintain PSEUD below 4 log10 CFU/mL when the delay exceeded 7 h. These data demonstrate the differential susceptibility of planktonic and sessile bacteria to RescuDerm™. This product might be a good candidate for reducing the opportunity for wound infection, especially in burns.