Aerosols are tiny particles suspended in the air.
They can be either solid or liquid and are generated when people cough or sneeze.
They are typically larger than 0.5 micrometers, but much smaller than droplets.
On February 19th, China's National Health Commission admitted that the novel coronavirus can be transmitted through aerosols.
It is a major shift from its previous stance that the virus is contracted through droplets and close contact.
So, here comes the most fundamental question: are aerosols more dangerous than droplets?
Aerosols can transmit the disease more easily because they are lighter and smaller than droplets, so are capable of staying in the air for longer.
Then, can we get infected just by breathing next to a patient?
The answer is no.
Experts say that aerosol infection is different from airborne infection, in which the virus floats in the air like tuberculosis.
They say aerosol infection rather only happens in certain conditions.
"It is prone to occur in hospital during medical procedures like inserting a tube into the respiratory system, which causes a burst of mass aerosols. That's why the medical staff there wear personal protective equipment."
So, the possibility of aerosol infection in our everyday lives is extremely low, but it could still happen when a patient sneezes really hard or when you are exposed to high concentrations of aerosol in an enclosed environment for a long period of time.
Then in those situations, can we still prevent aerosol infection?
Experts say wearing a mask can effectively prevent aerosol infection as well as blocking droplet infection.
"Any mask you wear to prevent coronavirus is capable of blocking aerosols."
The coronavirus may spread more easily than previously believed, but experts say droplet infection is still the main route of transmission.
Lee Kyung-eun, Arirang News.