Why the CDC Says the Pandemic Disinfecting Craze May Be Overkill

"All of the best epidemiological studies suggest that virtually all of the transmission occurs when two people share a space together,” says Aaron Richterman, an infectious diseases physician at Penn Medicine.

Early in the coronavirus pandemic, disinfecting products flew off store shelves after preliminary studies suggested that the virus could survive on surfaces for days.

However, the CDC notes that those experiments “do not necessarily reflect real-world conditions” or “account for inefficiencies in transfer of the virus between surfaces to hands and from hands to mouth, nose and eyes.”

Researchers in many of those early studies were actually finding fragments of the virus, called viral RNA, on surfaces, says Emanuel Goldman, a microbiologist at Rutgers New Jersey Medical School who wrote a commentary in The Lancet last July arguing that surfaces presented little risk.

While viral RNA can indicate the presence of the virus, it is actually “the corpse of the virus, what's left when the virus dies,” Goldman says. “Viral RNA cannot infect you."

Goldman is aware of only one study in which the live virus was found on a surface — on a package of frozen cod at a shipping dock in China. But even in that study, he says, the virus was no longer present by the time the product got to supermarkets.

The SARS-CoV-2 virus is actually quite fragile, Goldman explains, and quickly degrades on surfaces when it's exposed to light or when the environment is room temperature or higher.

Cleaning guidelines for public buildings

The CDC's revised guidance on cleaning comes as a growing number of Americans are getting vaccinated and more schools, businesses and public buildings are opening to the public. Many have spent millions of dollars on high-tech cleaning solutions and have put strict disinfectant protocols in place in an attempt to reassure the public.

That's “hygiene theater,” Goldman says, adopting a phrase coined last year in The Atlantic. “This is a virus you get by breathing. You don't get it by touching."

In its new cleaning guidelines for public spaces and businesses, the CDC says cleaning with soap or detergent once a day “is usually enough to sufficiently remove virus that may be on surfaces and help maintain a healthy facility,” as long as no one with confirmed or suspected COVID-19 is known to have been in a space.

Businesses and public buildings may want to clean more frequently or choose to disinfect if there is high transmission of COVID-19 in the community, if few people are wearing masks and washing hands, or if the building is used by people at higher risk from COVID-19, the CDC says.

The agency recommends against fogging, fumigation and electrostatic spraying, because those methods can carry safety risks.

Airflow and ventilation are more important

Cautious consumers or those who are still not vaccinated and concerned about getting COVID-19 should pay attention to a building's ventilation and air systems rather than to its cleaning regimen, Goldman says.

Richterman says consumers may still want to use a disinfecting wipe on high-touch public surfaces like a shopping cart handle or an airplane tray and seat. He notes that other viruses, including some stomach bugs, are known to be transmitted that way.

"For any high-touch surface, [using a disinfecting wipe] is a reasonable thing to do, especially if you have some medical vulnerability,” Richterman says.

But if you're concerned about getting COVID-19, don't worry too much about surfaces, he advises. Instead, you should “worry about indoor spaces, and close proximity to people outside your household. There's really not much transmission that occurs outside that context.”