Quirks and Quarks

Acknowledge COVID-19 is airborne, Lancet report urges as more evidence mounts

The COVID-19 coronavirus is predominantly spread through airborne transmission and it's time everyone acknowledges it, say researchers in a recent paper in the journal, The Lancet.

Canadian epidemiologist says distinction matters to take appropriate public health measures

Nurses and doctors in Toronto ride an elevator as they prepare to administer the Moderna coronavirus disease (COVID-19) vaccine. The Ontario Nurses' Association is demanding better PPE to protect nurses from the aerosol spread of COVID-19. (Carlos Osorio / Reuters)

The COVID-19 coronavirus is predominantly spread through airborne transmission and it's time everyone acknowledges it, say researchers in a recent paper in the journal, The Lancet.

The prevailing notion about how the virus spread through the early months of the pandemic focused on large respiratory droplets that are projected by coughing or sneezing into someone's eyes, nose, or mouth, or fall somewhere to contaminate a surface, where they can be picked up. 

As the pandemic has evolved more and more evidence  began to accumulate that much smaller particles produced, often by asypmptomatic or presymptomatic people, by speaking, singing or even breathing could carry the virus.

The World Health Organization, which many governments follow in making policy, has admitted that airborne spread is possible, but stops short of saying it's the dominant mode of spread. 

Dr. David Fisman, an epidemiologist at the University of Toronto's Dalla Lana School of Public Health and one of the co-authors of the Lancet paper, says this distinction matters in order for people to take the necessary precautions to keep themselves safe.

He said contrary to what he told Quirks & Quarks host, Bob McDonald in February 2020, he now believes the virus is primarily spread via tiny aerosol particles, and the Lancet article lays out the evidence that changed his mind.

Dr. Fisman said this means that indoor spaces where people from different households gather, like workplaces, need to be well ventilated by opening the windows, cleaning the air with HEPA filters, or upgrading ventilation systems. 

He also said N95 masks are ideal, especially in hotspots in spaces where you suspect ventilation isn't up to par and distancing isn't possible, but that cloth or surgical masks still help, to a lesser degree, if they fit well.

Produced and written by Sonya Buyting