US CDC acknowledges Covid is airborne, says virus can spread beyond 6 feet through aerosolised particles
Washington: The US Center for Disease Control and Prevention (CDC) reported that the principal mode by which people are infected with COVID-19 is through very fine droplets and aerosolised particles released during respiration.
The top US medical body said, "Inhalation of air carrying very small fine droplets and aerosol particles that contain infectious virus. Risk of transmission is greatest within three to six feet of an infectious source where the concentration of these very fine droplets and particles is greatest."
It however also warned that airborne virus can be transmitted even if the infectious source is farther than six feet in certain conditions, largely indoors.
"These transmission events have involved the presence of an infectious person exhaling virus indoors for an extended time (more than 15 minutes and in some cases hours) leading to virus concentrations in the air space sufficient to transmit infections to people more than 6 feet away, and in some cases to people who have passed through that space soon after the infectious person left," it reads.
The medical body's guidelines update comes nearly a month after a report in the Lancet medical journal claimed that there is consistent, strong evidence to prove that the SARS-CoV-2 virus is predominantly transmitted through the air.
Modes of SARS-CoV-2 transmission are now categorized as inhalation of virus, deposition of virus on exposed mucous membranes, and touching mucous membranes with soiled hands contaminated with virus.
"People release respiratory fluids during exhalation (quiet breathing, speaking, singing, exercise, coughing, sneezing) in the form of droplets across a spectrum of sizes.1-9 These droplets carry virus and transmit infection," said the top US medical body.
The analysis by six experts from the UK, US, and Canada said public health measures fail to treat the virus as predominantly the airborne route leave people unprotected and allow the virus to spread.
"The evidence supporting airborne transmission is overwhelming, and evidence supporting large droplet transmission is almost non-existent," said Jose-Luis Jimenez, from the University of Colorado Boulder in the US.
"It is urgent that the World Health Organization and other public health agencies adapt their description of transmission to the scientific evidence so that the focus of mitigation is put on reducing airborne transmission," Jimenez stated.
