Coronavirus stays active in air for 3 hours, up to days on surfaces

This was discovered when National Institute of Allergy and Infectious Disease (NIAID) scientists tried to figure out how long a virus, transferred to a surface by a person carrying the contagion, would last in a given setting.

To deposit the virus, as it would be by a person coughing or touching surfaces, researchers sprayed the virus via an aerosol spritzer, that mimicked the microscopic droplets that come from a person's mouth or nose. They measured the length of time the virus remained active.

In the air, the virus remained active for three hours, during which time it would be able to infect another person. On surfaces, particularly non-porous ones such as plastic and stainless steel, the virus was viable for up to three days. On copper, coronavirus only lasts 4 hours, while cardboard brings the active time down to 24 hours.

The half-life of the virus in an aerosol droplet is 66 minutes, which means that the particles lose half their functionability during that time. After an additional 66 minutes, half of those active particles will degrade, leaving 25 percent still active and infectious.

On copper, the half-life of the virus is only 46 minutes, the shortest length of viability of any surface.

The World Health Organization has been holding press briefings to update the global population on what's happening with the virus and infectious rates.