An aerosol is a tiny air particle, thinner even than the diameter of a strand of hair. And when an aerosol contains viruses such as SARS-CoV-2, which causes the disease COVID-19, it can be a deadly carrier at the center of a dangerous outbreak. The findings of the study are crucial for understanding the hidden transmission of the virus, through aerosols in the air and on objects, and researchers noted one key difference from previous coronaviruses is that people are spreading COVID-19 without experiencing symptoms or prior to recognizing symptoms.
When breathed, sneezed or coughed out, aerosols containing SARS-CoV-2 have been proven to linger in the air for several hours, according to a study published by The New England Journal of Medicine. The study also determined how long the virus can live on certain surfaces, such as plastic and steel.
The virus is thought to spread mainly from person-to-person. If viruses are released from people by breathing or talking, coughing or sneezing, they come out not as the naked virus but they come out associated in these little respiratory droplets which can then travel through the air.
- Between people who are in close contact with one another (within about 6 feet).
- Through respiratory droplets produced when an infected person coughs or sneezes.
These droplets can land in the mouths or noses of people who are nearby or possibly be inhaled into the lungs.
Can someone spread the virus without being sick?
- People are thought to be most contagious when they are most symptomatic (the sickest).
- Some spread might be possible before people show symptoms; there have been reports of this occurring with this new coronavirus, but this is not thought to be the main way the virus spreads.
Spread from contact with contaminated surfaces or objects
It may be possible that a person can get COVID-19 by touching a surface or object that has the virus on it and then touching their own mouth, nose, or possibly their eyes, but this is not thought to be the main way the virus spreads.
How easily the virus spreads
How easily a virus spreads from person-to-person can vary. Some viruses are highly contagious (spread easily), like measles, while other viruses do not spread as easily. Another factor is whether the spread is sustained, spreading continually without stopping.
The virus that causes COVID-19 seems to be spreading easily and sustainably in the community (“community spread”) in some affected geographic areas. People can also become infected if they touch a surface with the virus on it and then touch their eyes, nose or mouth.
Several factors can influence how long viruses like SARS-CoV-2, can live in the air, factors such as the size of droplets and outside forces.
The large ones, of course, settle quickly onto surfaces, the floor, things — and the smaller ones can stay afloat for a while. Movement of the air and ventilation can also play a role.
It also depends on the wind or the ventilation conditions in the room,” she continued. “If the air is kind of keeping them stirred up or if maybe the fan is blowing them down to the floor.
Other weather elements such as higher temperatures and humidity have been linked to a reduction in the spread of COVID-19 in recent studies, similar to what researchers have found in other respiratory illnesses like the flu in the past.