Touching Surfaces

Microorganisms are an integral component of human health on Earth as well as for life on the International Space Station. However, inescapably, fomites in human habitats can serve as crucial niches for opportunistic pathogens. To explore potential countermeasures for the associated infection risk, the Touching Surfaces experiment evaluated antibacterial surfaces as high-touch surfaces on the International Space Station and on Earth. We used copper-based surfaces that integrate chemical antimicrobial properties with topography, thereby creating a metasurface. 16S rRNA sequencing revealed that most bacteria found were human associated. While no significant distinction was observed between the microbial communities on the reference and antibacterial surfaces, isolation of microorganisms from the surfaces suggests that copper-based nanometer-structured surfaces exhibit enhanced antibacterial efficacy. The antibacterial efficacy of touched surfaces was reduced, as assessed by wet contact killing assays carried out using a methicillin-resistant Staphylococcus aureus (MRSA) isolate. The simplicity of the Touch Arrays' implementation allowed for straightforward testing of surfaces in both space and on Earth.