Public health units are giving outdated COVID-19 safety guidance. And experts say that could be dangerous
The complaint came to Durham Region's health department from a concerned resident, nervous about her risk of contracting COVID-19 from maskless colleagues working in an office.
The advice the health officials sent back was blunt: She was safe as long as they kept at least two metres apart from each other. Current evidence does not support airborne transmission," a Durham health official told her on April 8.
That advice contradicts mounting research and safety guidance from some of the world's largest health bodies. The Public Health Agency of Canada began warning as early as November 2020 that SARS-CoV-2 can spread from an infected person to others through aerosols, tiny particles that can linger in the air.
A Torstar review of the websites of 10 public health departments in the GTA and surrounding area - including Durham - found seven of them made no mention of aerosol transmission in fact sheets about COVID-19's spread. Four of the 10 agencies continued to disseminate outdated safety information that some experts say may actually be dangerous.
Up-to-date information from health units provides people with the tools to protect themselves from this virus," said David Fisman, an epidemiologist at the University of Toronto's Dalla Lana School of Public Health.
When you have misinformation coming out of health units it both deprives people of those tools, and also undermines the credibility of the health unit."
A Durham Region Health Department spokesperson said the April email was a specific reply" to a concerned resident about mask wearing at work, but did not directly answer questions about the department's stance on airborne transmission of COVID-19.
The website of Durham's health department states COVID-19 is spread mainly from person to person through close physical contact, containing no reference of airborne transmission.
Now that the airborne nature of COVID-19 is accepted worldwide, we can say with certainty that both close contact and airborne transmissions contribute to the spread of COVID-19," Dasantila Golemi-Kotra, a microbiologist at York University, said.
Prominent medical journals -- the Journal of the American Medical Association, the Lancet and of the National Academy of Sciences of the United States of America (PNAS) - have published papers identifying aerosols as the dominant mode of transmission of COVID-19.
Public health units say they seek guidance on the virus from Public Health Ontario (PHO), an arm's-length government agency, as well as heed the public health and workplace safety measures established by the government.
A recent Star investigation found those provincial public health guidelines have downplayed the risk of aerosol transmission, which health professionals say has led to a lack of critically important workplace protections.
Although the provincial government says it has for months acknowledged aerosol transmission in crowded workplaces, its safety precautions continue to focus on droplet contact measures that are not strong enough to prevent airborne risks, the investigation found.
Durham Region's health department and many other public health units across Ontario appear to have followed the provincial guidelines, and continued to advise that people are not required to wear a mask while working indoors with no public access if they can maintain a safe distance.
More than 7.5 million Ontarians - about 51 per cent of the population - have received at least one dose of COVID-19 vaccines as of May 22. Ontario logged nearly 1,700 new infections and 15 more deaths on that day.
Workplaces are the leading setting for COVID-19 outbreaks in Ontario. The province has had 252 active workplace outbreaks as of May 23.
The exemption to indoor masking when a physical distance can be maintained has been in place since the early stage of the pandemic, before aerosol transmission was widely accepted.
A health ministry spokesperson said COVID-19 is not an airborne infection" like measles and tuberculosis, noting the evidence strongly supports that personal protective equipment to protect against droplet/contact spread in hospitals is effective.
That's a ridiculous response from the government," Fisman said.
He noted there have been more than 400 deaths caused by COVID-19 acquired in hospitals and more than 500 hospital outbreaks of COVID-19 leading to thousands of infections.
The stubbornness" of public health authorities in refusing to admit they were wrong about the way COVID was transmitted comes at a great cost to health-care workers, patients and wider society, he said.
Fisman was among many worldwide experts who, in the earlier stages of the pandemic, cast doubts on the aerosol route of transmission. But as the evidence changed, so did his opinion, he said.
Over the past few months we've really seen a mountain of evidence emerge," he said. It isn't really a science question anymore."
Toronto Public Health, Canada's largest local public health agency, previously stated on its COVID-19 fact sheet that airborne transmission is not a common way" the virus is spread. After the Star asked about the statement, the agency revised it to list aerosol transmission as one of the common routes of transmission.
Prior to the May 13 update, Toronto's public health website also stated the virus is not known to spread through airborne transmission in community settings" - a statement that has since been removed.
These are the types of phrases that confuse people," Golemi-Kotra said.
She noted there have been many reported COVID-19 outbreaks in community settings such as weddings, birthday parties and gyms that led to outbreaks.
In York Region, where there have been more than 50,000 confirmed COVID-19 cases, the public health authorities continue to say COVID-19 is not known" to be spread in community settings on its website.
A spokesperson said York's public health unit is aligned with the provincial definition for COVID-19 routes of transmission and changes would be addressed by Public Health Ontario.
PHO, the agency that acknowledged aerosol transmission last December, updated its COVID-19 guidance May 20 to state SARS-Cov-2 is transmitted most frequently and easily" through both respiratory particles and aerosol.
The COVID-19 page of Peel Region, one of the hardest-hit areas in Ontario, says the virus can spread by touching something with the virus on it or through respiratory droplets. These droplets, emitted when talking, singing, shouting, coughing or sneezing, are larger and heavier than aerosols, so they quickly fall to the ground and don't linger in the air.
While Peel Public Health acknowledged aerosol spread in an email response to the Star May 18, mention of the transmission route continues to be non-existent on its COVID-19 page for the public.
In Halton, a region that has recently seen a spike in new COVID-19 cases in popular retail stores including Walmart and Real Canadian Superstore, public health states on its site that airborne spread has not been a dominant or common mode" of transmission.
In Durham Region, the complainant who was told there isn't evidence of airborne transmission said a follow-up call from the public health department advised that she unmask at her desk and that wearing a mask all day long may cause unnecessary fear" among co-workers.
Durham public health told the Star their advice was in compliance with the provincial rules for Stage 1 of Reopening that require indoor masking but exempt those who are not accessible to the public and can maintain a physical distance of at least two metres while in the indoor area.
While the health ministry said local health units should follow the Stage 1 requirements during the stay-at-home order, Golemi-Kotra said that the rules do not reflect the current situation."
These guidelines - initially introduced a year ago and revised in the fall - badly need an update - in order to prevent aerosol spread, Golemi-Kotra said.
Infectious aerosols linger in the air longer in poorly ventilated, confined spaces, and the enclosed areas that aren't crowded could still pose a risk of infection, she said, adding that all indoor workers should wear masks.
Sheila Wang is a municipal politics and general assignment reporter for YorkRegion.com and its sister papers. Reach her via email: swang@metroland.com