If you are using a single-layer cloth mask to protect yourself from a new COVID-19 variant that is believed to be more than six times as infectious as Delta “ditch it, full stop.”

At least that is the message from the scientific director of Ontario’s Science Advisory Table, who tells CP24 that there is likely a need for higher grade masks amid the threat posed by Omicron, particularly for frontline workers.

“One thing which is really important to realize is if you have a single layer cloth mask ditch it, full stop,” Dr. Peter Jüni said. “The minimum would be a double layered cloth mask that has been washed before so that it is denser and filters better and really fits well. Even better than that a medical mask below and the cloth mask on top and then it depends on your (exposure). If you are a bus driver for example it makes sense even to think about better protections.”

For much of the pandemic, government officials have resisted acknowledging that COVID-19 is transmitted via aerosol spread insisting that it was spread by droplets. But on Wednesday Chief Medical Officer of Health Dr. Kieran Moore told reporters that he is concerned that there could be “much more aerosol spread” with Omicron compared to previous strains of the virus.

Public Health Ontario also issued an advisory on Wednesday recommending that all healthcare workers treating suspected COVID-19 patients should wear respirator masks, which is a higher grade of mask than they were previously provided with in most circumstances.

The advisory says that the evidence did not support a significant protective effect of N95 respirator use over medical masks when caring for patients with suspected COVID-19 infections prior to the emergence of Omicron.

But it said that it is “unclear at this time if there is a change in the infectiousness of aerosols as a possible explanation for the increase in transmissibility” associated with the new variant, underscoring the need for caution until more is known. 

The order does not impact health-care workers who are not believed to be coming into contact with COVID-19 patients, despite concerns previously raised by the Ontario Nurses' Association in a court challenge in which they pushed for access to N95 masks.

Speaking with CP24 on Thursday, Jüni said that COVID is an “airborne disease” that is “transmitted through the airborne route” and we “need to acknowledge that in our protection.”

His comments come in the wake of science table co-chair Dr. Adalsteinn Brown telling reporters that the “highest quality mask you can get is useful” amid the rapid spread of the Omicron variant.

The science table currently estimates that cases involving the Omicron variant are doubling every 2.2 days due to its an increase infectiousness.

“It’s an airborne disease – I think that’s clear,” Brown said earlier on Thursday. “I think there's broader questions that should be addressed about types of masks and so on and I think there's guidance coming out on that shortly but that is a question for the chief medical officer of health.”

Ontario’s official guidance currently recommends that members of the public wear “non-medical masks or face coverings” only.

It states that medical masks, including N95s, should be “reserved for use by health care workers and first responders.”

Federal guidance published last month recommends respirator masks for anyone at greater risk due to the circumstances of their job or immunocompromised people.