CDC says risk of COVID-19 transmission on surfaces 1 in 10,000

The risk of getting a COVID-19 infection from contaminated surfaces is extremely low, according to updated guidance published Monday by the Centers for Disease Control and Prevention (CDC).

“It is possible for people to be infected through contact with contaminated surfaces or objects (fomites), but the risk is generally considered to be low,” the agency said. 

The principal mode by which people are infected with SARS-CoV-2 virus is through exposure to respiratory droplets, the CDC said. While not impossible, the agency said the risk of infection through fomites is “generally less than 1 in 10,000.”

The CDC guidance, coming more than a year into the pandemic, is the strongest argument yet against what some critics have dubbed “hygiene theater.” 

Despite the fact that scientists at the CDC have been fairly certain since at least last spring that transmission is almost entirely through airborne particles, establishments have continued to insist on strict sanitization protocols, like constantly wiping down shared surfaces with disinfectant, and closing schools and subways for “deep cleaning.”

According to the CDC, cleaning surfaces using soap or detergent, and not disinfecting, is enough to reduce risk in most situations. 

“There is little scientific support for routine use of disinfectants in community settings, whether indoor or outdoor, to prevent SARS-CoV-2 transmission from fomites,” the agency said. “In public spaces and community settings, available epidemiological data … indicate that the risk of SARS-CoV-2 transmission from fomites is low—compared with risks from direct contact, droplet transmission or airborne transmission.”

Disinfection is recommended in indoor community settings where there has been a suspected or confirmed case of COVID-19 within the last 24 hours, the CDC said. 

CDC Director Rochelle Walensky told reporters that other strategies being used, like fogging, fumigation and electrostatic spraying, are not recommended at all as primary methods of disinfection because of safety risks.

Surface transmission can be reduced by wearing masks consistently and correctly, as well as proper hand washing, the agency said.