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  • 1.  EPA OFFICIALLY SAYS COPPER SURFACES HELP FIGHT COVID-19

    Posted 04-01-2021 18:30

    Cu versus Ag as Antimicrobial

    In response to questions regarding antimicrobial efficacy copper vs silver,  I will describe a figure and a table from a peer reviewed published paper in 2009 ( https://www.amcopper.com/copper-versus-silver).  This paper compares the antimicrobial efficacy of two commercial silver-containing coatings versus six commercial copper alloys.

    This paper discusses test results showing the effects of temperature and humidity on antimicrobial  response of two commercial silver-containing coatings and six copper alloys,  after methicillin resistant Staphylococcus aureus (MRSA), a "Super Bug" that causes serious hospital-acquired infections was place on their surfaces.

    The figure shows a 7 log  (~10,000,000 times) reduction in reduction in live bacteria on a 99.9%Cu alloy in 80 minutes but no meaningful reduction in the two silver containing coatings at 400 minutes.  Stainless steel (S304) served as the experimental control and also showed  no meaningful reduction since it has no efficacy.

    The table shows the log reductions observer on six copper alloys and one silver containing coating at temperatures of 35C and 20C and relative humidity levels of >90RH% and ~20RH to 22RH.  

    • at >90% RH and ~35C, both the silver and six copper alloys achieved a    >6.4 log reduction
    • at >90% RH and ~20C, the silver log reduction was =5.5, but the six copper alloys achieved >6.1 log reduction
    • at >20% RH and ~35C, no log reduction (=0)  was seen in the silver, while the six copper achieving >5.5 log reduction. 
    • at >20% RH and ~25C, <0.2 log reduction was seen in the silver, but a >5. 9 was observed in five copper alloys and >5.0 in one copper alloy.

    The conclusion is that copper displays good antimicrobial efficacy under all humidity and temperature test conditions but silver only works at very high humidity levels, which are not typically found in indoor settings.

    Harold T. Michels, 

    Consultant, Formerly Senior Vice President, Copper Development Association.  Retired from Copper Dev Assoc in 2014 & Inco Ltd. in 1998.
    Manhasset NY,
    cu.microbes@gmail.com

     



    ------------------------------
    Harold Michels
    Consultant, Formerly Senior Vice President, Copper Development Association
    Retires from Copper Dev Assoc in 2014 & Inco Ltd. in 1998
    Manhasset NY
    (516) 627-5335
    ------------------------------

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  • 2.  RE: EPA OFFICIALLY SAYS COPPER SURFACES HELP FIGHT COVID-19

    Posted 04-02-2021 01:09
    I recall an article that I think CDA published years ago about a hospital in Chile (where they grow a lot of copper up in the Andes) where the beds, fixtures, tables, door handles -- pretty much everything was made from copper.  That hospital had a cross-infection rate that was extremely low.  Only the EPA, the FDA and the CDC would be reluctant to say that copper is a natural biocide, but at least we know that it kills the dreaded Covid-19!

    ------------------------------
    Walter Sperko
    President
    Sperko Engineering Services Incorporated
    Greensboro NC
    (336) 674-0600
    ------------------------------

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  • 3.  RE: EPA OFFICIALLY SAYS COPPER SURFACES HELP FIGHT COVID-19

    Posted 04-02-2021 09:23

    There was clinical trial conducted by CODELCO,  Chilean copper mining company, in a Pediatric Intensive Care Unit.  Prior to that, a study was conducted the CDA in the ICUs of three  hospitals.  The results of the US study showed that the infection rate was reduced by a statically significant 58% in the rooms where six copper components were installed, versus the typical rooms.  The six copper components were the : 

    • Rail of the Patient's Bed
    • I.V. Infusion Pole
    • Over-the-Patient Bed Table
    • Arms of the Visitor's Chair
    • Nurse's Call Device
    • Data Input Devices: Computer Mouse, Palm Rest on Laptop Computer or Palm Rest on Touch Screen

    To view the paper, Salgado, et. al., Copper Surfaces Reduce the Rate of Healthcare Acquired Infections in the Intensive Care Unit, go to: www.amcopper/infections



    ------------------------------
    Harold Michels
    Consultant, Formerly Senior Vice President, Copper Development Association
    Retires from Copper Dev Assoc in 2014 & Inco Ltd. in 1998
    Manhasset NY
    (516) 627-5335
    ------------------------------

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  • 4.  RE: EPA OFFICIALLY SAYS COPPER SURFACES HELP FIGHT COVID-19

    Posted 04-03-2021 08:29
    There was an article in AM&P in January (page 32 or 36 of pdf) on copper for Coronavirus.

    https://static.asminternational.org/amp/202101/#32


    Sincerely,

    Dan D.



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