The US Centers for Disease Control and Prevention (CDC) has acknowledged that the SARS-CoV-2 virus, which causes COVID-19, is airborne and can be transmitted through very fine aerosolised particles released during respiration.
The agency revised the guidelines on Friday where it mentioned that SARS-CoV-2 is transmitted through exposure to respiratory fluids carrying infectious virus.
It added exposure occurs in three principal ways: (1) inhalation of very fine respiratory droplets and aerosol particles, (2) deposition of respiratory droplets and particles on exposed mucous membranes in the mouth, nose, or eye by direct splashes and sprays, and (3) touching mucous membranes with hands that have been soiled either directly by virus-containing respiratory fluids or indirectly by touching surfaces with virus on them.
Although such transmission has long been factored in by many researchers and public health officials, the updated guideline now stressing that inhalation is one of the main ways the virus is spread is a change from the agency’s previous position that most infections were through close contact and surface transmission.
This comes nearly a month after a paper was published in The Lancet journal claiming that the SARS-CoV-2 virus is predominantly transmitted through the air.
Prevention of COVID-19 transmission
Heavier respiratory droplets containing virus fall to the ground or other surfaces under the force of gravity and the very fine droplets and aerosol particles that remain in the airstream progressively mix with, and become diluted within, the growing volume and streams of air they encounter.
To protect ourselves from inhaling tiny droplets in the air, one should maintain physical distancing, community use of well-fitting masks (e.g., barrier face coverings, procedure/surgical masks), adequate ventilation, and avoidance of crowded indoor spaces. These methods will reduce transmission both from inhalation of virus and deposition of virus on exposed mucous membranes.