Inactivation of Influenza A Virus on Copper versus Stainless Steel Surfaces April 7, 2020April 10, 2020 admin Findings: After 60 min on copper, the number of infectious virus particles was reduced to 5 x 105 , the equivalent of 24 h of exposure on stainless steel, with this number reducing further to 5 x 102 after 6 h PubMed ( Full-text )