Aerosol transmission of COVID-19 can exceed 6 feet, shoes can spread coronavirus on floors: study

Wuhan, China — SARS-CoV-2, the coronavirus that causes COVID-19, can be transmitted through the air beyond 6 feet and tracked across floors, results of a recent study conducted by researchers in China show.

The researchers collected swab samples from potentially contaminated objects in an intensive care unit and a general ward at Huoshenshan Hospital in Wuhan from Feb. 19 to March 2. The objects included floors, computer mice, trash cans, bed handrails, patient masks and personal protective equipment; indoor air and air outlets also were sampled. The ICU contained 15 patients with severe COVID-19, while the general ward had 24 patients with “milder disease.”

SARS-CoV-2 was detected in the air as much as 13 feet from the patients – more than twice the 6 feet distance the Centers for Disease Control and Prevention recommends for adequate physical distancing. Further, medical staff tracked the virus on the floor, as indicated by a 100% positive rate in a pharmacy where no patients were allowed.

“We highly recommend that persons disinfect shoe soles before walking out of wards containing COVID-19 patients,” the researchers said, adding that the rate of positivity was also “relatively high” on objects frequently touched by medical staff, including computer mice, trash cans, bed handrails and doorknobs.

“Sporadic positive results were obtained from sleeve cuffs and gloves of medical staff,” the study states. “These results suggest that medical staff should perform hand hygiene practices immediately after patient contact.”

Disinfecting patient masks before discarding them also is recommended.

The study was published online April 10 in the CDC journal Emerging Infectious Diseases.