People wear face masks as they walk along a street in Montreal, Sunday, Oct. 18, 2020, as the COVID-19 pandemic continues in Canada and around the world. THE CANADIAN PRESS/Graham Hughes

People wear face masks as they walk along a street in Montreal, Sunday, Oct. 18, 2020, as the COVID-19 pandemic continues in Canada and around the world. THE CANADIAN PRESS/Graham Hughes

Canada updates COVID-19 guidelines to include airborne transmission, following U.S., WHO

New information was updated after top doctor recommended triple-layer masks

The Public Health Agency of Canada quietly updated its COVID-19 guidelines this week to include aerosol, or airborne, transmission of the virus.

The move came sometime late Tuesday (Nov. 3) or early Wednesday morning, within 24 hours of the country’s chief medical officer recommendation that masks should be triple-layered, including a filter.

READ MORE: Third layer’s the charm: Canada’s top doctor unveils new face mask recommendations

In a section within Canada’s COVID-19 online information hub titled “How COVID-19 spreads,” the modes of transmission have been updated.

“COVID-19 spreads from an infected person to others through respiratory droplets and aerosols created when an infected person coughs, sneezes, sings, shouts, or talks. The droplets vary in size from large droplets that fall to the ground rapidly (within seconds or minutes) near the infected person, to smaller droplets, sometimes called aerosols, which linger in the air under some circumstances,” the website reads.

The new statement does acknowledge that the “relative infectiousness of droplets of different sizes is not clear.”

The updated information cites outbreaks that occurred in settings with poor ventilation, with the agency said “suggest that infectious aerosols were suspended in the air and that people inhaled the virus.” Those settings include choir practice, fitness classes and restaurants.

“Transmission in these settings may have been facilitated by certain environmental conditions, such as re-circulated air,” the agency’s COVID-19 information reads.

“There is no evidence at this time that the virus is able to transmit over long distances through the air, for example, from room to room through air ducts. It is still unclear how easily the virus spreads through contact with surfaces or objects.”

The prior statements on COVID-19’s mode of transmission included only close contact, meaning “breathing in someone’s respiratory droplets after they cough, sneeze, laugh or sing,” as well as contaminated surfaces and common greetings such as hugs, handshakes and kisses.

Canada’s move came months after other public health agencies began to update their COVID-19 transmission guidelines.

In July, the World Health Organization (WHO) released data suggesting that airborne transmission can spread the novel coronavirus.

“Airborne transmission of the virus can occur in health care settings where specific medical procedures, called aerosol generating procedures, generate very small droplets called aerosols. Some outbreak reports related to indoor crowded spaces have suggested the possibility of aerosol transmission, combined with droplet transmission, for example, during choir practice, in restaurants or in fitness classes.”

In October, the U.S. Centre for Disease Control (US CDC) stated that “COVID-19 can sometimes be spread by airborne transmission,” citing situations where people more than six feet away from others still got infected with the virus.


@katslepian

katya.slepian@bpdigital.ca

Like us on Facebook and follow us on Twitter.

Want to support local journalism during the pandemic? Make a donation here.

Coronavirus

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

Maple Ridge City Hall. (The News files)
Maple Ridge takes development services virtual

Building, planning and engineering services will be offered online only until end of the month

Thousands have converged in Whonnock Lake Park to enjoy the nice weather. (Roxanne Hooper/The News)
Thousands enjoy Maple Ridge park as city warns about social distancing

Portable toilets installed in anticipation of nice weather

COVID-19. (Image courtesy CDC)
Two new Maple Ridge schools have COVID-19 exposures

Alouette elementary and Maple Ridge secondary visited by virus

Ridge Meadows RCMP Const. Britteny George and Westview students turned old tires into pet beds. (Special to The News)
Maple Ridge students help turn old tires into pet beds

Westview art classes and RCMP constable take on project

Maple Ridge-Pitt Meadows Conservative MP Marc Dalton and former MP and Liberal candidate Dan Ruimy.
Dalton slams budget, Ruimy defends Liberal spending

Neither politician sees federal budget triggering an election

A lone traveler enters the Calgary Airport in Calgary, Alta., Monday, Feb. 22, 2021. THE CANADIAN PRESS/Jeff McIntosh
VIDEO: Trudeau defends Canada’s travel restrictions as effective but open to doing more

Trudeau said quarantine hotels for international air travellers will continue until at least May 21

B.C. Finance Minister Selina Robinson leaves the assembly with Premier John Horgan after the budget speech Tuesday, April 20, 2021. THE CANADIAN PRESS/Chad Hipolito
Paid sick leave for ‘hard-hit’ workers left out of provincial budget: BCGEU

‘For recovery to be equitable it requires supports for workers, not just business,’ says union president Laird Cronk

A large crowd protested against COVID-19 measures at Sunset Beach in Vancouver on Tuesday, April 20, 2021. (Snapchat)
VIDEO: Large, police-patrolled crowds gather at Vancouver beach for COVID protests

Vancouver police said they patrolled the area and monitored all gatherings

In this image from video, former Minneapolis police Officer Derek Chauvin, center, is taken into custody as his attorney, Eric Nelson, left, looks on, after the verdicts were read at Chauvin’s trial for the 2020 death of George Floyd, Tuesday, April 20, 2021, at the Hennepin County Courthouse in Minneapolis, Minn. THE CANADIAN PRESS/Court TV via AP, Pool
George Floyd’s death was ‘wake-up call’ about systemic racism: Trudeau

Derek Chauvin was found guilty Tuesday on all three charges against him

Cannabis bought in British Columbia (Ashley Wadhwani/Black Press Media)
Is it time to start thinking about greener ways to package cannabis?

Packaging suppliers are still figuring eco-friendly and affordable packaging options that fit the mandates of Cannabis Regulations

Former University of Victoria rowing coach Barney Williams is photographed in the stands during the Greater Victoria Invitational at CARSA Performance Gym at the University of Victoria in Victoria, B.C., on Friday, November 29, 2019. THE CANADIAN PRESS/Chad Hipolito
Rowing Canada sanctions former head coach of B.C. varsity women’s team

Suspension of Barney Williams would be reversed if he complies with certain terms

A man pauses at a coffin after carrying it during a memorial march to remember victims of overdose deaths in Vancouver. THE CANADIAN PRESS/Darryl Dyck
B.C. announces historic half-billion-dollar funding for overdose crisis, mental health

Of it, $152 million will be used to address the opioid crisis and see the creation of 195 new substance use treatment beds

Most Read