CDC: COVID-19 surface transmission rare

The risk of contracting COVID-19 from surfaces is far less than believed early in the pandemic.

The Centers for Disease Control and Prevention (CDC) says that the danger of contracting COVID-19 from surface transmission is low.

An update released April 5 showed that the risk of surface, or fomite, transmission of the disease is low compared with direct contact, droplet transmission, or airborne transmission.

Quantitative microbial risk assessment studies have suggested that the risk of fomite transmission of COVID-19 is generally low with a less than one in 10,000 chance that contact with a contaminated surface would cause an infection, according to the update.

Various studies have shown that COVID-19 can survive for minutes to hours on porous surfaces and for days to weeks on non-porous surfaces. Under typical indoor environmental conditions a 99 percent reduction in infectious COVID-19 and other coronaviruses within three days, the update says.

Cleaning and disinfection further reduce the risk of infection through surface transfer, but efficacy varies on the type of product. While no studies have looked at the effectiveness of cleaning surfaces on reducing concentrations of COVID-19, studies on cleaning other microbes showed a 90 to 99.9 percent reduction depending on the method and the surface being cleaned, according to the update.