Figure 1.
Effects of influenza A virus on steel surface (top) and copper surface (bottom). The influenza virus was cultured in R-mix vials that contain a monolayer of mink lung and human laryngeal carcinoma cells grown on glass coverslips. This was inoculated into sterile coupons of copper (C11000) and steel (20 µL virus suspension with 108 virus particles per millilitre) for the experimental purpose and kept at room temperature (22 ± 2 °C) with a relative humidity of 50 to 60%. Here in the epifluorescent image, the number of green fluorescing cells are proportional to the viral inoculum. After six hours, 106 virus particles were found to be remained viable on the steel surface, and after 24 h, 5 × 105 particles were present, capable of causing cell infection (top). In contrast to the steel surface, on copper, the virus particles reduce to 5 × 105 after 60 min (the equivalent of 24 h of exposure on stainless steel), which reduced to 5 × 102 after six hours (nearly 4 log reduction). After 24 h of incubation, 500,000 virus particles were present on stainless steel, but 500 only seen after six hours on the copper surface. Adapted with permission from Ref. [92]. Copyright 2007, American Society for Microbiology.