This Is How Much Coronavirus You Could Be Spreading Without Knowing It

Even if you're asymptomatic, here's how easy it is to spread COVID-19 at home and beyond.

By now, we all know that even if we're not symptomatic of coronavirus we can still spread it to others. Yet simultaneously, many of us still find it difficult to truly internalize the idea that we wouldn't somehow know if we were putting our loved ones at risk. As it turns out, even without a telltale cough to spread droplets with ease, many asymptomatic patients are indeed spreading coronavirus, by contaminating their surroundings via touched surfaces—and the rate of contamination may shock you.

One study revealed that in fact 40 percent of surfaces in hospital rooms of confirmed coronavirus patients were contaminated with SARS-CoV-2, the causative agent of COVID-19. Sampled surfaces included door handles, light switches, sinks, toilet bowls, drains, bedside tables, bedding, and more—all common household items that we touch on a daily basis.

With a combined group of study subjects that were both symptomatic and asymptomatic, researchers found that both subgroups left traces of the virus on commonly touched surfaces. "In particular, in a single room with an asymptomatic patient, four sites including bedrail, pillow, bedsheet and the air exhaust outlet were SARS-CoV-2 positive," the study explains. This highlights that asymptomatic COVID-19 patients can indeed contaminate their surroundings and put their family members or healthcare workers at risk of exposure.

Perhaps most disturbingly, the sampled rooms that yielded these high rates of contamination were frequently cleaned before testing. "The rooms and toilets were cleaned and disinfected by nurses twice daily using a 2,000-mg/liter chlorine solution," noted the researchers, who retrieved their samples between four and seven hours after the first daily cleaning. In other words, despite a rigorous disinfection routine, it didn't take long for the patients—even the asymptomatic ones—to recontaminate their surroundings.

Still, the study emphasized the importance of regular environmental cleaning and the disinfection of surfaces as an important line of defense against the virus. As health authorities have advised, it's wise to assume you have coronavirus and act accordingly at all times: stay six feet apart from others, wear masks in public, wash your hands regularly, and disinfect the surfaces in your home at least daily—regardless of how you feel. And for more on under-the-radar COVID cases, find out why If You're Asymptomatic, You May Be More Likely to Get the Coronavirus Again.

Lauren Gray
Lauren Gray is a New York-based writer, editor, and consultant. Read more