How COVID-19 Spreads

Current understanding about how the virus that causes coronavirus disease 2019 (COVID-19) spreads is largely based on what is known about similar coronaviruses.

Person-to-person spread

The virus is thought to spread mainly from person-to-person. 

Between people who are in close contact with one another (within about 6 feet) 

Via 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. 

Spread from contact with infected 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.

When does spread happen? 

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 with this new coronavirus, but this is not thought to be the main way the virus spreads. 

How efficiently does the virus spread?

How easily a virus spreads from person-to-person can vary. Some viruses are highly contagious (like measles), while other viruses are less so. Another factor is whether the spread continues over multiple generations of people (if spread is sustained). The virus that causes COVID-19 seems to be spreading easily and sustainably in Hubei province and other parts of China. In the United States, spread from person-to-person has occurred only among a few close contacts and has not spread any further to date.

There is still more to be learned

COVID-19 is an emerging disease and there is more to learn about its transmissibility, severity, and other features and what will happen in the United States. New information will further inform the risk assessment.