A few hours, but there’s a more dangerous source — the air

Published: April 30, 2020 | Updated: November 16, 2022

A study in the New England Journal of Medicine found that the coronavirus can live in the air and on surfaces between several hours and several days. The study found that the virus is viable for up to 72 hours on plastics, 48 hours on stainless steel, 24 hours on cardboard and four hours on copper.

The World Health Organization notes those surfaces “can easily be cleaned with common household disinfectants that will kill the virus.”

The important thing to remember is that as time goes on, there is very little of the virus left on those surfaces. At the 72-hour mark, for example, there is less than 0.1% of the starting amount of viral material. So, while infection from touching a surface is possible, it is not likely.

A more likely contagion

What is more likely is contracting COVID-19 from the air, since it is mainly transmitted between people through “respiratory droplets” when symptomatic people sneeze or cough.  The virus is detectable in the air for three hours, and that is why it is so important to leave home only if you are working, shopping for essentials or going somewhere far from other people.

The Centers for Disease Control and Prevention (CDC) recommends these steps for protecting yourself:

• Wash your hands often with soap and water for at least 20 seconds immediately when you return home from a public place such as the bank or grocery store.
• When in a public space, put a distance of 6 feet between yourself and others.
• Most importantly, stay home if you are sick, and contact your doctor.

If you or someone in your home has a suspected or confirmed case of COVID-19, be sure to have the sick person stay in a room away from the other inhabitants of the home. Surfaces in the home should be cleaned regularly with disinfectant. You can learn more about cleaning recommendations and procedures at CDC.gov.