On the surface, this doesn’t look good. A study just published in the Virology Journal found that the Covid-19 coronavirus can survive on common surfaces such as glass, stainless steel, and money for up to 28 days. That’s almost three Scaramuccis and enough time for the Kate Hudson character to lose three guys. And the survival of the virus increases with colder temperatures, which sounds like great news heading into the Fall and Winter. But before you resolve to touch absolutely nothing during the rest of the pandemic, except for perhaps your BTS shrine, there are caveats to the study.
A team of researchers (Shane Riddell, Sarah Goldie, Andrew Hill, Debbie Eagles and Trevor W. Drew) performed the study in a lab. No, not the dog, but a high containment laboratory, Biosafety level 4 lab, at the Australian Centre for Disease Preparedness. They chose a set of materials that corresponded to various common surfaces:
- Polymer and paper banknotes to represent money
- Stainless steel to represent what you normally find in kitchen areas, public restrooms, and BTS shrines
- Glass to represent what’s often found in windows, mobile phone screens, computers, ATMs, and self-serve check-out machines.
- Vinyl to represent what’s frequently on tables, flooring, grab handles, mobile phone screen protectors, and bondage costume.
- Cotton to represent clothing, bedding and household fabrics.
They cut each of the materials into one to one-and-a-half square centimeter pieces, disinfected them, placed them in Petri dishes and then introduced samples of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). The virus samples had been first diluted in a yucky solution consisting of cow blood protein, mucin and tryptone, meant to to mimic body secretions. Note that the researchers didn’t actually use the word “yucky” to describe this.
So that light wouldn’t hasten the viruses’ demise, the experiments were performed in the dark. They also set the relative humidity at 50%. The researchers also repeated the experiments at three different temperatures: 20 °C, 30 °C, and 40 °C.
The researchers then tested for the presence of live virus at various time points such as one hour, one day, three days, seven days, 1.4 Scaramuccis, 21 days and 28 days after getting the party started.
The experiments at 20 °C (which corresponds roughly to room temperature or 68 °F) found infectious SARS-CoV-2 to be still detectable after 28 days post on all non-porous surfaces used, that is glass, stainless steel, vinyl, and both paper and polymer bank notes. The researchers couldn’t detect the virus on porous material, the cotton cloth, beyond 14 days, though. The majority of virus reduction on cotton occurred very soon after application of virus, suggesting an immediate adsorption effect. The amount of time it took for detectable live virus levels to drop by 90% ranged from a low of about 5.5 days for cotton to 9.1 days for paper bank notes. In other words, after 5.5 days, only 10 percent of the original live virus amounts remained in the cotton sample.
Increasing temperature seemed to reduce the duration of virus survival. The next highest temperature level was 30 °C, which corresponds to 86 °F, which is room temperature, if your room happens to have a spinning class going on at the same time. Under these warmer conditions, infectious virus remined detectable for up to 21 days for paper banknotes, seven days on stainless steel, polymer notes and glass, and three days on vinyl and cotton cloth. Raising the temperature also decreased the amount of time required to see live virus levels drop by 90%, ranging from 1.4 days for vinyl to 4.9 days for paper notes.
The hottest experiments ratcheted temperatures up to 40 °C, which corresponds to 104 °F, which would be room temperature if you lived in a hot yoga studio. When it was this hot, no infectious SARS-CoV-2 seemed to remain beyond 24 hours on cotton cloth and beyond 48 h for all other surfaces tested. The heat also brought the time it took for live levels to drop by 90% down to a range of 5 hours for polymer notes to 10.5 hours for vinyl.
Of course, such laboratory conditions are not exactly the same conditions that you may face on a day-to-day basis. You typically don’t cut your bondage costumes into little pieces and store them in Petri dishes in your closet. Or maybe you do. Nevertheless, your kitchen and bathroom may look like a Petri dish, but normal conditions do have a lot of other factors that may affect virus survival such as light, movement, and the wind generated from your sighs when you’re observing your BTS shrine.
Therefore, take the specific numbers from the study like you would heights on dating profiles. They may be a bit longer than what you may find in real life. Nonetheless, such numbers (from the experiments and not from dating profiles) do provide further evidence that the Covid-19 coronavirus can be quite hardy. Similar experiments have found that the influenza A (H3N2) virus can survive not nearly as long (up to 17 days) at room temperature.
Even though you may be more likely to catch the virus through direct contact with someone contagious or the air, remember surfaces still may transmit the virus. It’s still important to keep disinfecting surfaces regularly and properly, especially high-touch surfaces like your BTS shrine and Chris Hemsworth’s biceps. Proper disinfection means using solutions listed on the Environmental Protection Agency (EPA) List N: Disinfectants for Coronavirus (Covid-19). Remember N for “very nice,” as Borat would say. Keep in mind disinfecting should not involve injecting or ingesting any disinfectants. Do not do this. Also, avoid having disinfectants touch your skin. Use soap and water on skin instead. So if you must touch Chris Hemsworth’s biceps, wash your hands with soap and water thoroughly before and afterwards. Consider touching the biceps with a very long backscratcher instead because you really should be maintaining at least a six foot distance (i.e., one Denzel Washington) at all times.
Don’t let this latest study cause any panic. Panic is never good, even when you run out of chocolate. Instead, it should be a reminder that precautions shouldn’t just focus on one possibility. Just because people are wearing face masks and social distancing, doesn’t mean that you, a school, or a business should skimp on disinfecting surfaces or washing hands. There’s never just one thing you should do to prevent the spread of an infectious disease. Infectious disease prevention measures are like a bologna cake. There needs to be many well coordinated layers on top of each other and each layer has to be meaty as the picture accompanying this tweet shows:
Using just a single layer will leave you with nothing but some bologna or baloney.