A U.S. study recently analyzed how long the new coronavirus can survive in aerosols. However, local news reports amplified the result to raise the possibility of the deadly virus causing airborne infections, experts said.
The U.S. National Institutes of Health’s National Institute of Allergy and Infectious Diseases (NIAID), the Centers for Disease Control and Prevention (CDC), and researchers of the University of California on March 17 released a report in the New England Journal of Medicine.
It compared the survival of COVID-19 virus with that of the SARS (Severe Acute Respiratory Syndrome) virus in aerosols and on various surfaces.
|Choi Jae-wook (left), a professor at the Preventive Medicine Department of Korea University College of Medicine, appears on a YouTube show Friday by K-Healthlog, a channel operated by The Korea Doctors' Weekly, together with science journalist Kang Yang-gu (center), and Shin Hyun-young, a professor at the Family Medicine Department of Myongji Hospital|
The researchers used “Collison nebulizer” to generate an aerosolized environment and found that the SARS virus and COVID-19 virus had similar survival rates. An aerosol is a solid or liquid particle floating in the air and has a diameter of about 1 µm. Aerosols may occur during intubation or suction at an intensive care unit.
According to the report, 12.5 percent of COVID-19 viruses survived for three hours in an aerosolized environment, and their half-lives were 66 minutes, similar to those of the SARS viruses.
COVID-19 viruses also survived up to 72 hours on plastic and stainless surfaces, up to 24 hours on cardboard, and up to four hours on copper.
“Our results indicate that aerosol and fomite transmission of COVID-19 virus is plausible since the virus can remain viable and infectious in aerosols for hours and on surfaces up to days,” the report said, adding that medical institutions could be vulnerable to the virus in this sense.
While the report was about the survival of the COVID-19 virus in aerosols, local media outlets exaggerated the result as if COVID-19 could cause airborne infections, local experts said.
Choi Jae-wook, a professor at the Preventive Medicine Department of Korea University College of Medicine, said the report did not mean that people could get infected in the air in daily and outdoor activities, appearing at a YouTube show, Friday by K-Healthlog, a channel operated by The Korea Doctors' Weekly.
He explained that aerosols containing a virus could occur in particular sites such as hospitals.
“Aerosols occur when mucus of a patient comes out from the upper respiratory tract through coughing, or when a patient with a lot of sputum is suctioned or incubated in a hospital,” Choi said. “In some patients, upper respiratory tract infections can result in a lot of mucus, causing aerosols.”
Shin Hyun-young, a professor at the Family Medicine Department of Myongji Hospital, said media reports on the possible survival of the COVID-19 virus for three hours added to the public fear.
“This study was conducted in a closed lab. It cannot be applied to outdoor activities or daily lives,” she emphasized.