Decontamination of Nosocomial Bacteria IncludingClostridium difficileSpores on Dry Inanimate Surface by Cold Atmospheric Plasma

Microbial control is important to prevent nosocomial infections. Cold atmospheric plasma (CAP) is studied as an alternative disinfectant for dry surfaces. Bacterial endospores including Clostridium difficile and vegetative bacteria including Enterococcus faecium are treated on carriers, considering European testing standards. CAP reduces the spore load (106 cfu) by at least 3 log10 as required, independent from the bioburden (≤10 min treatments). Only a 2 log10 reduction is achieved with vegetative bacteria due to multilayer formation resulting from a higher required load (108 cfu). However, densities <10−7 cfu cm−2 enable disinfection by CAP. Elemental mapping identified other influencing burden. Overall, this study demonstrates possibilities and limitations of CAP treatment for disinfecting purposes.