In the brave new world of Covid-19, home is your sanctuary, the one place you want to be sure is virus-free.
But if you have to head outdoors, what are the best practices for decontaminating your things when you return home? Does everything – smartphones, wallets, money and keys – need to be washed down with hot water and soap?
"We are all swimming through an invisible swamp of bacteria, viruses, fungi and parasites," noted Dr Stephen Berger, co-founder of the Global Infectious Diseases and Epidemiology Network in Tel Aviv, Israel. "Those bookshelves and those pictures on the wall are teeming with ugly microbes. Not to mention your cellular phone, wristwatch, eyeglasses and everything else in your world."
In fact, "the list of objects which could potentially be contaminated is endless," he cautioned.
True culprit your own hands
But that does not mean that everything you take outdoors needs a biohazard scrub-down upon return, Berger added.
"The good news is that you are in no danger from most of this," said Berger. "And you have no reason to compulsively avoid, or even clean, every object in your personal world. With one exception: your own hands!"
Why? Because when it comes to Covid-19 infection risk, "the true culprit here is your own hands," he said.
Which is not to say that inanimate objects don't pose any risk. They do, said Berger. And guidelines from the US Centers for Disease Control and Prevention recommend that people do clean their phones and electronics, either following the manufacturers' guidelines or by using wipes or sprays containing at least 70% alcohol.
"The current Covid-19 pandemic is caused by a virus. That virus will infect you through your nose or mouth, in most cases because somebody coughed – or perhaps only breathed – within a few feet of you," Berger said.
Money is 'dirty'
"But perhaps that same somebody coughed into his hand, or toward a nearby object, or simply opened a door. Later that day, you shake that hand in greeting, touch that table or grasp that doorknob. And then, you use your own contaminated hand to eat a snack," he explained.
The potential risk: that you then get infected, and "for the next week or two, this virus is multiplying in your system," he added.
Money is a good example of the problem, Berger noted. "Few people realise that money is – as our mother told us many times – 'dirty'. Several researchers have demonstrated an amazing variety of bacteria, parasites and other living things on paper bills."
New research scheduled for presentation this month at the European Congress of Clinical Microbiology and Infectious Diseases speaks to that concern.
Though the investigation, led by Johannes Knobloch of the University Medical Center Hamburg-Eppendorf in Hamburg, Germany, didn't focus specifically on Covid-19, it did find evidence that European paper money – made of cotton fibre – is vulnerable to microbial contamination. (Coins, which are 75% copper in Europe, are less so.)
Soap and water also does the job
Still, "the solution here is not to throw your money away, or wash it in detergent," Berger said. Nor does it mean spraying your keys down with Lysol. Instead, he suggested, the solution is "caution and hygiene".
"In terms of the Covid pandemic, 'caution' involves strict attention to avoiding potential sources of disease," said Berger, meaning wearing face masks and practicing physical distancing. "While 'hygiene' must include careful and repeated handwashing, antiseptics and chemical wipes are fine. But simple soap and water also does the job."