Antimicrobial activity of copper surfaces against carbapenemase-producing contemporary Gram-negative clinical isolates

temperature. Results: Copper demonstrated antimicrobial activity against all studied isolates. This effect was observed earlier and was more pronounced for Cu99% than for Cu63%. Cu99% showed a bactericidal effect after ,2 h for A. baumannii, 3 h for Enterobacter spp., 5 h for K. pneumoniae and 6 h for P. aeruginosa and E. coli. No viable colonies were recovered from five (20.8%) isolates after 3 h and from nine (37.5%) isolates after 5 h of incubation on Cu99%. Conclusions: Copper has significant antimicrobial activity against multidrug-resistant nosocomial Gramnegative pathogens. This supports the hypothesis that replacement of high-contact materials with copper could reduce the high burden of environmental contamination around high-risk patients. However, this strategy should be seen as an adjunctive measure to established cleaning protocols and to good hygiene practices for prevention of hospital-acquired infections.