MIT researchers: Risk of contracting COVID-19 indoors the same at 6ft and 60ft

The risk of contracting COVID-19 indoors is the same when socially distanced 6 feet apart and 60 feet apart, researchers at the Massachusetts Institute of Technology (MIT) say.

The study, published in the Proceedings of the National Academy of Sciences of the United States of America earlier this month, argues that there isn’t much benefit to distancing 6 feet apart.

Ideas about coronavirus transmission have changed since the beginning of the pandemic. At the start of the global outbreak, scientists and medical professional believed that hand-washing after touching surfaces was the leading cause of transmission. Experts now say the virus is transmitted through droplets released when people talk, sneeze and cough. 

Professor Martin Bazant, who teaches chemical engineering and applied mathematics at MIT, told CNBC that the rule “really has no physical basis because the air a person is breathing while wearing a mask tends to rise and comes down elsewhere in the room so you’re more exposed to the average background than you are to a person at a distance.”

Bazant and MIT applied mathematics professor John Bush created a model to calculate exposure risk to COVID-19 in an indoor setting based on the amount of time indoors, air filtration, immunizations, variants and respiratory activity like breathing.

They say the most important factor is the amount of time spent indoors rather than how far apart people stand from one another. 

“What our analysis continues to show is that many spaces that have been shut down in fact don’t need to be,” Bazant told CNBC.

He continued by arguing that if a space is large enough with proper ventilation, the amount of time spent in those spaces is such that “those spaces can be safely operated even at full capacity and the scientific support for reduced capacity in those spaces is really not very good.”

Both the Centers for Disease Control and Prevention (CDC) as well as the World Health Organization recommend maintaining a 6-foot distance from others, specifically in indoor settings.

The CDC says it’s important to maintain such distance even if you or the other person doesn’t have symptoms.

However, the agency last month dropped the distancing guidance to 3 feet for classroom settings.