There is not a lot of cause in this space for referencing research published in the New England Journal of Medicine, but we live in curious times.
A letter in the much-respected publication outlines the results of testing the lifespan of the novel coronavirus on a variety of surfaces – a hot button issue, for some, in this industry, because of worries about transmitting the pathogen by using a touchscreen.
My inbox steadily sees PR for product launches of contactless alternatives like voice and smartphone-to-screen pairing apps – all touting alternatives to touch interaction.
A team of researchers analyzed the aerosol and surface stability of SARS-CoV-2 and compared it with SARS-CoV-1, the most closely related human coronavirus.
Our data consisted of 10 experimental conditions involving two viruses (SARS-CoV-2 and SARS-CoV-1) in five environmental conditions (aerosols, plastic, stainless steel, copper, and cardboard).
The findings are the sorts of things that will turn people who don’t work in medical research cross-eyed, but the barebones of it is that the virus lives longer on plastic and stainless steel surfaces than it does on copper surfaces or cardboard.
Viable virus was detected up to 72 hours after application on plastic and stainless, while on copper, no viable SARS-CoV-2 was measured after 4 hours. On cardboard, no viable SARS-CoV-2 was measured after 24 hours, though the research team was cautious about the cardboard findings.
The longest viability of both viruses was on stainless steel and plastic; the estimated median half-life of SARS-CoV-2 was approximately 5.6 hours on stainless steel and 6.8 hours on plastic. Estimated differences in the half-lives of the two viruses were small except for those on cardboard. Individual replicate data were noticeably “noisier” (i.e., there was more variation in the experiment, resulting in a larger standard error) for cardboard than for other surfaces ), so we advise caution in interpreting this result.
There are manufacturers out there marketing enclosures that have copper plating in areas where they might get regular touching, as well as lots of anti-microbial covers for screens. Copper has known anti-microbial properties, but as the research suggests, it doesn’t kill the virus immediately. The anti-microbial overlays stop the pathogen’s growth, but that overlay does not make it “safe” to use a touchscreen. The anti-microbial technology stops growth, so the pathogen slowly – repeat slowly – dies.
I note this, in part, because I have read some messages/posts/comments in social media that drafted off CDC guidelines, suggesting the virus does not spread easily via contaminated surfaces … so don’t worry about touchscreens. The New York Times has a post up that updates where that thinking is.
The real story, for now, seems to be that no matter what you touch, there is risk. Counter-measures like anti-microbial coatings or copper can help, but are part of a broader solution, not THE solution.
The best measures, particularly in the context of touchscreens, are cleaning the touch surface regularly, and properly with the right solutions. More than anything, using soap and water or hand sanitizer gel or spray after touching that surface – or anything else for that matter, like a hand rail or door handle.
The argument I have been hearing lately about touchscreens is that while they present a surface that could – like any surface – be resident to a lingering pathogen, that set-up is less risky to the shopper or diner, and the staff of that business, than one-to-one contact at a sales, order or service counter.
Dave Haynes is the founder and editor of Sixteen:Nine, an online publication that has followed the digital signage industry for some 14 years. Dave does strategic advisory consulting work for many end-users and vendors, and also writes for many of them. He’s based near Halifax, Nova Scotia, on Canada’s east coast.