Earlier this week on Tuesday afternoon, the World Health Organization acknowledges the emerging evidence of the airborne spread of the novel coronavirus (COVID-19), following pressures from a group of scientists urging the global health body to update its guidance on how COVID-19 passes between people.
“We have been talking about the possibility of airborne transmission and aerosol transmission as one of the modes of transmission of COVID-19,” said Dr. Maria Van Kerkhove, technical lead on the COVID-19 pandemic at the WHO, told a news briefing.
Previously, the WHO stated that COVID-19 primarily spread through small microdroplets expelled from the nose and mouth of an infected person, that was said to quickly sink to the ground.
This idea was generally accepted by health officials around the world until recently when a group of 239 scientists in 32 countries outlined new evidence, they say shows that the floating virus particles can infect people who breathe them in.
Citing evidence that smaller exhaled particles can linger in the air, the scientists have written an open letter to the WHO urging them to update its guidance on the COVID-19 virus.
“We are concerned that people may think they are fully protected by following the current recommendations, but in fact, additional airborne precautions are needed to further reduce the spread of the virus,” wrote the lead author and Queensland University of Technology air quality expert Lidia Morawska.
In a briefing from Geneva, Professor Benedetta Allegranzi, the WHO’s Technical Lead for Infection Prevention and Control, said that there was emerging evidence of airborne transmission of COVID-19.
However, the professor would further clarify that the evidence is not definitive.
“The possibility of airborne transmission in public settings – especially in very specific conditions, crowded, closed, poorly ventilated settings that have been described, cannot be ruled out,” she said.
“However, the evidence needs to be gathered and interpreted, and we continue to support this.”
The debate over the term “airborne” and the safety precautions over COVID-19 virus spread
While the WHO has acknowledged the evidence brought forward by the group of 239 scientists around the world, it seems as though not everyone is on the same page regarding how the COVID-19 virus spreads.
Some Canadian infectious diseases experts are saying not to get too caught up on the term “airborne” as the current safety precautions have already been shown to slow the spread of the virus.
Dr. Bonnie Henry, British Columbia’s Provincial Health Officer praised the WHO saying they are “doing an amazing job trying to keep up with what’s going on”.
In her opinion, she thought the letter from the scientists was “trying to foment a bit of controversy”.
The B.C. Provincial Health Officer added that while COVID-19 did seem to be released in small droplets as well as larger droplets, it is unknown as to how potent the smaller particles are in terms of infecting a person.
“Where there’s some challenges is how much is due to the small aerosols which are transmitted when I’m close to you, or the larger droplets that tend to fall out more readily,” said Dr. Bonnie Henry.
“So it’s really a bit of nuance, I think.”
Commenting on the matter addressed by the WHO, Dr. Colin Furness, an Epidemiologist with the University of Toronto said “To the general public the word (airborne) can be pretty confusing because it suggests that COVID is gonna come through the keyhole and get you in your sleep. And well, it isn’t”.
According to an example from one of the studies that were presented to the WHO, droplets of COVID-19 were found to be the most likely source of transmission among three dining parties at a restaurant in China.
Surveillance video footage from the restaurant showed that there was no direct or indirect contact between the groups, yet transmission of the virus still occurred.
From Dr. Sumon Chakrabarti’s perspective, as an infectious disease physician based in Mississauga Ontario, he believes the possibility of airborne transmission of COVID-19 is overshadowed by the evidence that Canada and other countries have been able to slow down the spread of the virus.
In his view, Canada and other countries which have already implemented precautions and restrictions focusing on preventing droplet transmissions, and they were proven to be effective at limiting the spread of COVID-19.
“Are there situations where the two metres is a bit too little, for example, a karaoke bar or a choir, where you’re singing and your voice is propelling? Perhaps,” said the Mississauga based Epidemiologist.
“But I think, for the most part, the recommendations that have been there since the beginning are the ones that are truly preventing the spread of this virus.”
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