AEROSOL & DROPLET TRANSMISSION

Subject: Science & tech

Context: Aerosols and Droplets are Key Transmission Modes of COVID-19 Virus, Can Travel in Air Up to 10 Meters: Centre

Concept:

Aerosols and droplets are key transmission modes of the Covid-19 virus, and while droplets fall within 2 meters from an infected person, aerosols can be carried in the air up to 10 meters.

Aerosol Transmission

This new mode could be ‘aerosols,’ tiny liquid particles from the respiratory tract generated when someone exhales, talks, or coughs.
They can float in the air and can contain live viruses unlike droplets which do not float but settle down on ground or any surface in one-two minutes after exhalation.
When inhaled, these aerosols make everyone vulnerable to viral infection.
Confirmed presence of the virus in air-filters and ducts in hospitals with Covid-19 patients also means that it predominantly transmits in the form of aerosol.
The widespread presence of the virus and its ability to spread through aerosols suggest that a lockdown will have minimal to no impact on Covid-19 spread.

Aerosols

Aerosols are defined as a combination of liquid or solid particles suspended in a gaseous or liquid environment.
In the atmosphere, these particles are mainly situated in the low layers of the atmosphere (< 1.5 km) since aerosol sources are located on the terrestrial surface.
However, certain aerosols can still be found in the stratosphere, especially volcanic aerosols ejected into the high altitude layers.

Droplet Transmission

The droplets spread during sneezing, speaking, and coughing by an infected person can spread infections.
The infections can also spread by touching the nose and mouth with the hands contaminated with infectious droplets.
The droplets are so minute that they travel only a short distance before falling. The people nearby might contract infections.