Actividad bactericida de superficies de cobre frente a bacterias asociadas a infecciones nosocomiales, en un modelo in vitro de adherencia y sobrevivencia

Resumen

ADHERENCE TO COPPER AND STAINLESS STEEL METAL COUPONS OF COMMON NOSOCOMIAL BACTERIAL STRAINS

Background: Copper has a bactericidal activity against a series of bacterial strains. Aim: To measure resistance to bacterial adherence of copper (Cu) and stainless steel (SS) metal coupons.  Material and methods: Bacterial strains causing nosocomial infections in Chile were analyzed. Bacterial Adherence was studied using a previously described method based on a system of metal coupons that are immersed in culture media containing the bacteria of interest at room temperature.  Results: Adherence to Cu and SS coupons was different for Methicillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae and Acinetobacter baumannii strains.  For these strains, no adherence to Cu coupons occurred during  the 48 h observation period compared to a rapidly increasing adherence to SS coupons, with a final colony count of 1.00E+07 cfu/mL.  For two different Pseudomonas aeruginosa clinical strains, inhibition of adherence was not observed on Cu coupons, and colony counts were similar for Cu and SS using the standard inoculum (2-3  x 10 ⁷  cfu). A partial decrease in adherence was observed for Cu but not for SS coupons, when a lower inoculum was used.  Conclusions: Copper surfaces represent an interesting option to reduce bacterial contamination in the hospital environment due to its resistance to bacterial adhesion of most of the common nosocomial bacterial strains.