How long can the virus live on surfaces?

Be cautious within reason, expert says

With four COVID-19 cases from community transmission now in Saskatchewan, many people are voicing concerns over the potential spread of COVID -19 on surfaces like food at the grocery store and reusable shopping bags.

So how worried should we be about getting the disease from these surfaces?

When someone is sick with COVID -19, they expel small, invisible droplets of saliva by coughing or sneezing that contain SARSCOV-2, the novel coronavirus that causes the highly contagious disease COVID-19.

“Another person nearby can inhale those, or it could land on a surface that another person nearby will contact quickly and then potentially transmit to their mouth or eyes or nose by rubbing with their hands,” explained Andrew Cameron, an associate professor of biology at the University of Regina who has researched infectious diseases.

He said these droplets do not last very long in the air before settling onto surfaces, but how long the virus can live on surfaces is not yet fully known.

“Our understanding of the virus is evolving very, very quickly, so at the moment we’re still only working with a partial image and understanding of how it transmits,” said Cameron.

A study published in The New England Journal of Medicine on March 17 showed that the new coronavirus lives on different surfaces for different amounts of time. The virus survived for four hours on copper, 24 hours on cardboard, and three days on plastic and stainless steel. The longer the virus is on a surface, the less likely it is to spread infection.

GROCERY STORE

“Even though the virus is losing viability relatively quickly outside of the body, there’s still some detectable even after that long period of time,” said Cameron.

This means items like cellphones, books or fabrics can potentially spread the virus.

In a setting like the grocery store, where many people have been touching items and surfaces, Cameron said it is good to be “cautious within reason.”

While he believes picking up fresh produce or grabbing a box of cereal is likely only a “very minor form of transmission,” Cameron said the possibility could not be ruled out completely. High touch surfaces like grocery cart handles or doors made of plastic or stainless steel are more likely to be an issue.

Several stores are discouraging or no longer accepting reusable bags because of COVID-19 concerns, including Save-on-foods.

“Both our team members and customers have expressed concern about bottle returns and in using reusable bags at this time and we want to do everything we can to put them at ease,” said Save- Onfoods president Darrell Jones in a news release issued Wednesday.

But Cameron reminded people that just getting the virus on your hands is not enough to become infected. It is touching your eyes, nose or mouth with your hand that can then pass along the infection. This is why frequent hand washing, especially after being in a public place, is so important.