You Can Get Covid-19 From Coronavirus-Contaminated Surfaces, New Study Confirms

On the surface of things, these findings make sense. A new study just published in The Lancet Microbe showed that detecting the Covid-19 coronavirus on people’s hands and on frequently-touched household surfaces was associated with transmission of the virus. In other words, the results from this study provided further evidence that the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can spread not only through contact with infected people and the air but also via contaminated hands and surfaces. Thus, it does make sense to keep washing your hands frequently and making sure that your lathering with soap and water lasts through all the lyrics of “Happy Birthday” or at least the first chorus of the Divinyls song “I Touch Myself.” It also makes sense to keep regularly disinfecting high-touch surfaces such as keyboards, mice (not real live mice but computer mice), table tops, door knobs, and Chris Hemsworth’s biceps.

This study recruited people in London, UK, who were diagnosed with Covid-19 from September 2020 through March 2021. This covered the pre-alpha (September to through the end of November 2020) and alpha (B.1.1.7; December 2020, through the end of March 2021) variant phases of the Covid-19 pandemic. The research team from Imperial College, London, dubbed these initial recruits “primary cases” and then repeatedly tested for SARS-CoV-2 the hands of these primary cases and the hands of those who shared the same household with these primary cases. The study also involved repeatedly testing frequently-touched surfaces in the communal spaces of those households.

During the study period, the research team identified 620 primary cases and then continued to test 414 people who shared 279 households with the primary cases. Ultimately, 28·4% of the household mates ended up getting infected during the pre-alpha phase and 51·8% during the alpha phase. While the rates of transmission to did not correlate with amount of virus that the primary cases had in their upper respiratory tract, such rates did correlate with the detection of SARS-CoV-2 RNA on primary cases’ hands. In fact, household members were 70% more likely to catch the SARS-CoV-2 if the primary cases had detectable SARS-CoV-2 on their hands and 66% more likely if the high-touch surfaces in communal areas of the household had detectable SARS-CoV-2. When household members had detectable SARS-CoV-2 on their hands, they were 106% or over twice as likely to have developed Covid-19. Moreover, in six cases where household members ended up catching the SARS-Cov-2, the primary cases didn’t even have PCR-detectable SARS-CoV-2 in their upper respiratory tracts. Detectable SARS-CoV-2 was present either in their hands or on high-touch surfaces. All of this suggested rather strongly that shared surfaces did a play a role in at least some of the transmission that occurred in the household.

As they say, hindsight is 2020. Back then, early in the Covid-19 pandemic, experts repeatedly urged everyone to disinfect surfaces and wash their hands. That’s because studies had already shown that the SARS-CoV-2 could stay on surfaces for hours as I covered for Forbes at time (as well as subsequently in later 2020 and 2022).

However, in the Spring of 2020, a twist emerged as I reported in May 2020 for Forbes. Studies began “airing” the fact that the SARS-CoV-2 wasn’t spreading in the exact same way as other respiratory viruses like the flu. No, this new virus could go airborne via small respiratory droplets in addition to large droplets. Such aerosolized virus particles could travel well beyond the six feet range that large respiratory droplets can travel as well as hang in the air like a fart for extended periods of time. This prompted experts to recommend face mask use and air filtration/purification as key interventions to stop the spread of the virus

A funny thing happened along the way. This wasn’t funny is a “ha-ha” type of way. It was more funny in terms of the quirks of human nature. There can be a tendency for many humans to focus on only one thing at a time such as Chris Hemsworth’s biceps or, well, Chris Hemsworth’s biceps. The belief that a greater percentage of new Covid-19 cases were due to aerosol transmission rather than contact with contaminated surfaces led to a lot more talk about face masks than disinfecting surfaces. And just like that, the whole keep objects and surfaces clean and disinfected thing seemed to fade more into the background. This was a bit unfortunate since after all, you can still do several things at once such as wearing underwear and a shirt at the same time.

Throughout this Covid-19 pandemic, there has been a tendency to forget about Swiss cheese. Not real Swiss cheese, which is yummy, but the Swiss Cheese model that Ian M. Mackay, PhD, a scientist and an adjunct Associate Professor at the University of Queensland, advanced back in 2020. This model was a metaphor to emphasize the fact that no single intervention was going to be enough to tackle the pandemic. Each policy and intervention has its holes. And it’s usually good in general to cover up your holes. This can be done by combining or layering different policies and interventions on top of each other, better coordinating things like testing, surveillance, vaccination, face mask use, air filtration/purification, cleaning/disinfection, and treatment.

Now, this doesn’t mean that you have to aggressively disinfect everything that you may end up touching like wiping down packages that haven’t been touched by anyone for a while. It does mean that there is value in keeping objects and surfaces that are regularly touched clean. This should not only help prevent Covid-19 but also the flu and whole host of other viral and bacteria infections. High-touch surfaces can transmit many different pathogen, which is a big reason why you shouldn’t go around liking door knobs.

Hand-washing is good in general as well. Don’t look at the easing up of the Covid-19 pandemic as license to stop hand washing. You shouldn’t be saying, “Thank goodness, I can now go back to scratching my crotch and shaking people’s hands immediately.” If you see on someone’s Tinder profile, “Not into the regular hand-washing thing,” you may want to swipe left because you may up swiping up pathogens from that person.

Of course, regularly cleaning and disinfecting surfaces and providing hand sanitizer and sinks and soap to wash hands costs money. So one has to wonder how many businesses, schools, and other organizations have continued to invest in such capabilities since 2020. In the long run, such investments are worthwhile, though. Since getting employees and customers sick is not good for business, finding better ways to prevent the spread of infectious diseases shouldn’t be such a touchy subject.