For respiratory illnesses like COVID-19, the disease caused by the coronavirus, the medical community focuses on two primary ways that the virus can spread: airborne transmission and what's known as droplet transmission.

With droplet transmission, it's thought that virus-filled particles can be ejected from the mouth or the nose when a person speaks, coughs or sneezes.

Measles, chickenpox and tuberculosis are other diseases that can spread through airborne transmission.

While airborne and droplet transmission are different, they aren't mutually exclusive, said Dr.

When we think about COVID-19, there may be some airborne transmission, but it's safe to say that the majority of transmission falls toward the droplet side of the spectrum.".

If COVID-19 was truly airborne, Bogoch said, infection rates among health care workers would have skyrocketed

"If I'm in a crowded room with a bunch of infected people, there's bound to be aerosol transmission there, but if I'm in a big room or I'm outside and someone is walking nearby, I'm not too worried about aerosols," he said

And regardless of whether it's mandated, people should wear masks in public, del Rio said