CDC: Disinfecting Surfaces to Prevent Covid Often Serves Just for 'Show'

Disinfecting surfaces in excess could be harmful 0:41

(CNN) -

The risk of surface transmission of covid-19 is low, the U.S. Centers for Disease Control and Prevention (CDC) said on Monday.

Far more important is airborne transmission, and people obsessively disinfecting surfaces may be doing more harm than good.

"The CDC determined that the risk of surface transmission is low and secondary to the primary routes of transmission of the virus through direct contact with droplets and aerosols," said Vincent Hill, chief of the Waterborne Disease Prevention Branch. , in a conference call sponsored by the CDC.

Hill said the risk of transmission from touching a surface, although small, is high indoors.

Outdoors, the sun and other factors can destroy viruses, Hill said.

The virus dies "quickly" on porous surfaces, but can persist longer on hard interior surfaces.

The research also suggested that surface transmission was most likely in the first 24 hours after a person was infected, and that households where a person had COVID-19 had lower transmission rates when the household cleaned and disinfected surfaces.

So while keeping surfaces clean isn't a waste of time, it's not the only or even the most important way to reduce risks, the CDC said.

They have updated their guide to surface cleaning and disinfection in community settings in light of this transmission risk.

advertising

"In most situations, cleaning surfaces with soap or detergent, rather than disinfecting, is enough to reduce the already low risk of virus transmission through surfaces," Hill said.

"Generally, it is not necessary to disinfect surfaces, unless a sick or COVID-19 positive person has been in the house in the last 24 hours."

Hill said cleaning should focus on high-touch areas like doorknobs and light switches.

• Surface disinfection in the era of covid-19: these are the new recommendations from the CDC

Household cleaners pose a hazard

People may be using household cleaning products to protect themselves from COVID-19, but misuse can have dangerous consequences, Hill added.

Frequent cleaning and disinfection of surfaces can have minimal impact on viral transmission and contribute to the "hygiene theater," he added.

"Show off" with cleaning and disinfecting "can be used to give people a sense of security that they are being protected from the virus, but this can be a false sense of security, if other prevention measures, such as the use of masks, distancing and hand hygiene are not done consistently, "said Hill.

"It could also make people feel less of a need to participate in these other important prevention measures."

Additional data shows that disinfectants themselves can pose a risk.

"Public consultations indicate that some people may deliberately drink, inhale or spray their skin with disinfectants, not understanding that using disinfectants in this way can cause serious harm to their bodies," he said.

Hill cited CDC research from June 2020 showing that, of those surveyed, “only 58% knew that bleach should not be mixed with ammonia, because bleach and ammonia mix creates a toxic gas that damages the lungs. of people".

And bleach itself can be harmful.

“19% wash food products with bleach, which could lead to the consumption of bleach that is not washed, which can harm the body because bleach is toxic.

18% percent used household cleanser on bare skin, which can damage the skin and cause rashes and burns, ”Hill said.

• Accidental poisoning of children with disinfectants on the rise during the pandemic (2020)

Hill added that surveillance data shows that the volume of calls to poison centers in 2020 for disinfectants was higher than in 2018 or 2019.

Alternative disinfection methods can also be time-wasting or even risky, the CDC says in the updated guide.

"The effectiveness of alternative methods of surface disinfection, such as ultrasonic waves, high intensity ultraviolet radiation, and blue LED light against the virus that causes COVID-19 has not been fully established," the CDC says on its updated website.

Covid-19