Ottawa doctor calling for more public COVID-19 info regarding risk of shared indoor air

A doctor at the Ottawa Hospital Rehab Centre's Division of Physical Medicine and Rehabilitation thinks we're fighting a losing battle against COVID-19 because, to this point, public health messaging regarding COVID-19 transmission has been incomplete.

Dr. Jennifer McDonald says public health authorities at the federal, provincial and local levels have been great about hammering home important messages like keeping proper physical distance from others and good hand hygiene, but no one is directly addressing the risk of shared indoor air.

“We have lots of factories, buildings, schools, long-term care facilities with terrible ventilation, terrible indoor air quality, and these places are essentially breeding grounds for COVID-19,” she explains.

According to the doctor, it's like being in a room with a smoker. 

“Assume that the cigarette smoke is COVID, and you're near that person, obviously it's going to be a stronger smell of smoke and more noxious if you're standing within two metres. If you stand across the room from that person, you're not going to smell the smoke right away — it's going to be pretty light and it's not going to be too bothersome,” says Dr. McDonald. “But if that room you're in happens to have poor ventilation, which many rooms do, if you wait 10-20 minutes, well now the smell of smoke is going to start building up and you're going to be bothered by that.”

The Ottawa doctor is one of more than 500 signatories on a letter, sent Monday, calling for the federal and provincial governments to address the transmission of the virus through aerosols. 

Dr. MacDonald says aerosols are tiny droplets that can linger in the air. On CityNews' The Rob Snow Show, she says there's a debate in the medical community over whether to call the virus “airborne,” or whether to say it's transmitted through aerosols, but she remains adamant that either way, this is extremely important information in the fight against COVID-19 transmission. 

Dr. McDonald would like to see the governments educate the public about airborne transmission, which might include encouraging additional measures like opening windows, encouraging people to buy extra air filters or turning on vents to the outside of homes. 

Carbon dioxide (CO2) monitors can also be good screening tools for how bad ventilation may be in a room, says the doctor. CO2 levels outdoors are around 420, which Dr. McDonald says stays roughly the same in a well-ventilated hospital, for example. But many long-term care homes, especially ones built decades ago, can see CO2 levels in the 2,000s. She adds that many residential homes are even around 1,500.

Another key piece of public health information which Dr. McDonald doesn't think has been made clear enough to the public is that all facemasks should now be three layers thick and should be fitted to your face.

Listen to the full interview with Dr. McDonald here: