• Sebastian Leck

FACT CHECK: Can you get COVID-19 from touching contaminated surfaces?

MOSTLY TRUE. Becoming infected with COVID-19 from surface contamination is possible, but it is not likely to be a major source of transmission. However, more research is needed to know for sure.

On May 21, media outlets like the Washington Post and Global News reported that the US Centers for Disease Control and Prevention (CDC) changed its guidelines to say COVID-19 does not spread easily through contact with contaminated surfaces.

Those stories were based on updates to a CDC webpage called “How COVID-19 spreads,” which now says: “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. This is not thought to be the main way the virus spreads, but we are still learning more about how this virus spreads.”

The CDC quickly clarified that the changes were only meant to make the website “easier to read” and did not reflect a change in guidelines. But the edits raised questions about the level of risk from surface contamination and how safe it really is to touch objects in public places.

Mixed recommendations across public health authorities

In Canada, the federal government’s summary on COVID-19 research says that the virus can survive on surfaces from several hours to days, but doesn’t mention how risky it is for members of the public to, for example, touch a park bench or pick up a can of soup at a grocery store.

At the provincial level, information varies. The Alberta government says the virus is “believed to be spread mainly by coughing, sneezing or direct contact with someone who is sick with COVID-19 or with surfaces they have recently touched,” while the Quebec government states that spread via objects and surfaces is “not the main mode of transmission” and the BC government’s guide doesn’t mention surfaces at all.

Research so far has been insufficient

There’s been little research about COVID-19 cases acquired by touching contaminated surfaces. One of the main studies cited by public health authorities found that the COVID-19 virus can live up to 24 hours on cardboard and up to three days on plastic and stainless steel. However, the study also found that the virus begins to disintegrate when droplets land on a surface, so it becomes less and less infectious over time.

An Ontario government research summary from April noted that there is “currently no data on the ability of COVID-19 to survive or be transmitted through surfaces.” Instead, the report says there is indirect evidence that suggests, but doesn’t prove, that surfaces could play a role. For example, studies have found that the virus stays on some surfaces in the rooms of patients who tested positive for COVID-19.

Contaminated surfaces may have also been behind an outbreak at a mall in Wenzhou, China, where researchers couldn’t discover a direct link between people who became sick. In that case, though, we can’t rule out the possibility that asymptomatic people spread the virus.

A spectrum of risk

The New York Times spoke to a number of infectious disease experts who agreed that surfaces are probably not a main driver of transmission. “There’s a long chain of events that would need to happen for someone to become infected through contact with groceries, mail, takeout containers or other surfaces,” Julia Marcus, an epidemiologist at Harvard Medical School, told the Times.

That doesn’t mean washing your hands and avoiding touching your face aren’t important, though. There is a spectrum of risk that spans from activities that are totally safe (staying at home) to moderate risk (outdoor activities) to high risk (indoor gatherings). The idea is to minimize potential exposure and take the right precautions in each scenario.

Overall, surfaces likely don’t drive transmission in the same way as person-to-person contact, but researchers believe it is still possible to become infected with the virus by touching contaminated surfaces and then touching your mouth, nose, or eyes. Both regular hand washing and making an effort not to touch your face will help prevent the spread of COVID-19.